however need limit oneself substructures signature since formulas ''n'' free variables define subsets math mathcal n math ''n'' ary relations also definable functions definable function graph definable relation constants math mathcal math definable formula math varphi x math ''a'' element math mathcal math math varphi math true way one study definable groups fields general structures instance important geometric stability theory one even go one step


move beyond immediate substructures given mathematical structure often associated structures constructed quotient part original structure via equivalence relation important example quotient group group one might say understand full structure one must understand quotients equivalence relation definable give previous sentence precise meaning say structures ''interpretable'' key fact one translate sentences language interpreted structures language

Humanities
Philosophy
Logic
Mathematical logic
Model theory


original structure thus one show structure math mathcal math interprets another whose theory undecidable math mathcal math undecidable types basic notions sequence elements math dots n math structure math mathcal math subset ''a'' math mathcal math one consider set first order formulas math varphi x dots x n math parameters ''a'' satisfied math dots n math called ''complete n type realised by'' math dots n math ''over a'' automorphism math mathcal math constant ''a'' sends math dots n math math b


dots b n math respectively math dots n math math b dots b n math realise complete type ''a'' real number line math mathbb r math viewed structure order relation serve running example section every element math mathbb r math satisfies type empty set clear since two real numbers ''a'' ''b'' connected order automorphism shifts numbers ''b a'' complete type empty set realised pair numbers math math depends order either


math math math math math math subset math mathbb z subseteq mathbb r math integers type non integer real number ''a'' depends value rounded nearest integer generally whenever math mathcal math structure ''a'' subset math mathcal math partial ''n type a'' set formulas ''p'' ''n'' free variables realised elementary extension math mathcal n math math mathcal math ''p'' contains every formula negation ''p'' ''complete'' set complete ''n'' types ''a'' often written


math n mathcal math ''a'' empty set type space depends theory ''t'' math mathcal math notation math n math commonly used set types empty set consistent ''t'' single formula math varphi math theory math mathcal math implies math varphi rightarrow psi math every formula math psi math ''p'' ''p'' called ''isolated'' since real numbers math mathbb r math archimedean real number larger every integer however compactness argument shows elementary extension real number line


element larger integer therefore set formulas math n x n mathbb z math type math mathbb z subseteq mathbb r math realised real number line math mathbb r math subset math mathcal n math expressed exactly elements math mathcal n math realising certain type ''a'' called ''type definable'' ''a'' algebraic example suppose math math algebraically closed field theory quantifier elimination allows us show type determined exactly polynomial equations contains


thus set complete math n math types subfield math math corresponds set prime ideals polynomial ring math x ldotsx n math type definable sets exactly affine varieties structures types every type realised every structure every structure realises isolated types types empty set realised structure isolated types structure called ''atomic'' hand structure realises every type every parameter set one takes math mathcal math parameter set every type


math mathcal math realised math mathcal math isolated formula form ''a x'' math mathcal math however proper elementary extension math mathcal math contains element ''not'' math mathcal math therefore weaker notion introduced captures idea structure realising types could expected realise structure called ' 'saturated'' realises every type parameter set math subset mathcal math smaller cardinality math mathcal math automorphism constant ''a'' always preserve types ''a''


realise type countable set math mathbb z math implies ''x'' larger integer rational number line math mathbb q math saturated contrast since math mathbb q math countable therefore realise types finite subsets saturated stone spaces set definable subsets math mathcal n math parameters math math boolean algebra stone 's representation theorem boolean algebras natural dual topological space consists exactly complete math n math types math math topology generated sets form math p


means every countable dense linear order order isomorphic rational number line hand theories math mathbb q math math mathbb r math math mathbb c math fields math omega math categorical follows fact fields infinitely many natural numbers defined formula form math x dots math math aleph math categorical theories countable models also strong ties oligomorphic groups complete first order theory ''t'' finite countable signature math omega math categorical automorphism group


uncountable cardinals kappa morley 's proof revealed deep connections uncountable categoricity internal structure models became starting point classification theory stability theory uncountably categorical theories many points view well behaved theories particular complete strongly minimal theories uncountably categorical shows theory algebraically closed fields given characteristic uncountably categorical transcendence degree field determining isomorphism type theory math omega math categorical uncountably categorical called ''totally categorical'' selected applications among early successes


first significant result model theory special case downward l wenheim skolem theorem published leopold l wenheim compactness theorem implicit work thoralf skolem first published lemma kurt g del 's proof completeness theorem l wenheim skolem theorem compactness theorem received respective general forms anatoly maltsev development model theory independent discipline brought alfred tarski member lw w warsaw school interbellum tarski 's work included logical


extending concepts results first order model theory logical systems saharon shelah 's work around categoricity morley 's problem changed complexion model theory giving rise whole new class concepts stability theory classification theory shelah developed since late aims classify theories number different models given cardinality next decades became clear resulting stability hierarchy closely connected geometry sets definable models gave rise subdiscipline known


geometric stability theory connections related branches mathematical logic finite model theory finite model theory fmt subarea model theory mt deals restriction interpretations finite structures finite universe since many central theorems model theory hold restricted finite structures fmt quite different mt methods proof central results classical model theory fail finite structures fmt include compactness theorem g del 's completeness theorem method ultraproducts first order logic main application areas fmt


descriptive complexity theory database theory formal language theory set theory set theory expressed countable language consistent countable model known skolem 's paradox since sentences set theory postulate existence uncountable sets yet sentences true countable model particularly proof independence continuum hypothesis requires considering sets models appear uncountable viewed ''within'' model countable someone ''outside'' model model theoretic viewpoint


useful set theory example kurt g del 's work constructible universe along method forcing developed paul cohen shown prove philosophically interesting independence axiom choice continuum hypothesis axioms set theory direction model theory formalized within zfc set theory instance formalization satisfaction zfc done inductively based tarski 's schema observation members range variable assignments lie development fundamentals


shown equivalent large cardinal axioms see also algebraic theory axiomatizable class compactness theorem descriptive complexity elementary equivalence first order theories hyperreal number institutional model theory kripke semantics l wenheim skolem theorem model theoretic grammar proof theory saturated model skolem normal form connection web ontology languages owls description logics notes references canonical textbooks textbooks free online texts hodges wilfrid '' http platostanfordedu entries model theory model theory '' stanford encyclopedia philosophy e zalta ed hodges wilfrid '' http platostanfordedu entries modeltheory fo first order model theory '' stanford encyclopedia philosophy e zalta ed simmons harold '' https webarchiveorg web http wwwcsmanacuk hsimmons books modeltheorypdf


monotone sense ''a'' subset ''b'' measure ''a'' less equal measure ''b'' furthermore measure empty set required '''measure''' fundamental concept mathematics measures provide mathematical abstraction common notions like mass distance length area volume probability events adjustments electrical charge seemingly distinct concepts innately similar may many cases treated mathematically indistinguishable measures foundational probability theory far reaching generalizations measure widely

Formal science
Mathematics
Pure mathematics
Probability theory
Measure theory


used quantum physics physics general intuition behind concept dates back ancient greece archimedes tried calculate area circle late th early th centuries measure theory became branch mathematics foundations modern measure theory laid works mile borel henri lebesgue johann radon constantin carath odory maurice fr chet among others definition measure countable disjoint union sum measures subset let set


algebra function extended real number line called '''measure''' satisfies following properties '''non negativity''' '''null empty set''' math mu varnothing math '''countable additivity''' additivity countable collections math e k k infty math pairwise disjoint sets math display block mu left bigsqcup k infty e k right sum k infty mu e k math least one set math e math finite measure requirement math mu varnothing math met automatically indeed countable additivity math mu e mu e cup varnothing mu e mu varnothing math therefore math mu varnothing math condition non negativity omitted


second third conditions met takes one values called '' 'signed measure''' pair called measurable space members called '''measurable sets''' math left x sigma x right math math left sigma right math two measurable spaces function math f x math called '''measurable''' every measurable set math b sigma math inverse image measurable ie math f b sigma x math setup composition measurable functions measurable making measurable spaces measurable functions category


measurable spaces objects set measurable functions arrows see also '''' another setup triple called measure space probability measure measure total measure one ie probability space measure space probability measure measure spaces also topological spaces various compatibility conditions placed measure topology measures met practice analysis many cases also probability theory radon measures radon measures alternative definition terms linear functionals


locally convex space continuous functions compact support approach taken bourbaki number sources details see article radon measures instances important measures listed counting measure defined number elements lebesgue measure complete translation invariant measure '' '' algebra containing intervals every measure properties extends lebesgue measure circular angle measure invariant rotation hyperbolic angle measure invariant squeeze mapping


haar measure locally compact topological group generalization lebesgue measure also counting measure circular angle measure similar uniqueness properties hausdorff measure generalization lebesgue measure sets non integer dimension particular fractal sets every probability space gives rise measure takes value whole space therefore takes values unit interval measure called ''probability measure'' see probability axioms dirac measure '' '' sub ''a'' sub cf dirac delta function given '' '' sub ''a'' sub ''s''


'' '' sub ''s'' sub '' '' sub ''s'' sub indicator function measure set contains point otherwise 'named' measures used various theories include borel measure jordan measure ergodic measure euler measure gaussian measure baire measure radon measure young measure loeb measure physics example measure spatial distribution mass see eg gravity potential another non negative extensive property conserved see conservation law list negative values lead signed measures see generalizations liouville measure known also


natural volume form symplectic manifold useful classical statistical hamiltonian mechanics gibbs measure widely used statistical mechanics often name canonical ensemble basic properties let measure monotonicity measurable sets math mu e leq mu e math measure countable unions intersections subadditivity countable sequence necessarily disjoint measurable sets math mu left bigcup infty e right le sum infty mu e math continuity measurable sets math e n subseteq e n math union sets


measurable math mu left bigcup infty e right lim infty mu e sup geq mu e math continuity measurable sets math e n subseteq e n math intersection sets measurable furthermore least one finite measure math mu left bigcap infty e right lim infty mu e inf geq mu e math property false without assumption least one finite measure instance let ''n'' '''r''' infinite lebesgue measure intersection empty


properties completeness measurable set called ''null set'' subset null set called ''negligible set'' negligible set need measurable every measurable negligible set automatically null set measure called ''complete'' every negligible set measurable measure extended complete one considering algebra subsets differ negligible set measurable set symmetric difference contained null set one defines


equal x f x x f x ae math mu math measurable function math f math takes values math infty math math mu x f x geq mu x f x math almost math mathbb r math respect lebesgue measure property used connection lebesgue integral role presentation class wikitable mw collapsible mw collapsed '''proof''' math mu x f x math math mu x f x geq math monotonically non increasing functions math math continuous almost everywhere relative lebesgue measure math mu x f x infty math math math additivity


non negativity math mu x f x geq mu x f x mu x f x infty math required contrary math mu x f x neq infty math math math unique math infty cup infty math function infinite left math math happen math geq math finite right arguing math mu x f x geq infty math math math math math let math n math monotonically non decreasing sequence converging math


analogous probability measures sense finite measure proportional probability measure math frac mu x mu math measure called '' finite'' decomposed countable union measurable sets finite measure analogously set measure space said '' finite measure'' countable union sets finite measure example real numbers standard lebesgue measure finite finite consider closed intervals integers countably many intervals measure


measure space may 'uncountable measure' finite measures measure said finite countable sum bounded measures finite measures general sigma finite ones applications theory stochastic processes non measurable sets axiom choice assumed true proved subsets euclidean space lebesgue measurable examples sets include vitali set non measurable sets postulated hausdorff paradox banach tarski paradox generalizations certain purposes useful measure whose


values restricted non negative reals infinity instance countably additive set function values signed real numbers called ' 'signed measure'' function values complex numbers called ''complex measure'' measures take values banach spaces studied extensively measure takes values set self adjoint projections hilbert space called ''projection valued measure'' used functional analysis spectral theorem necessary distinguish usual measures take non negative values generalizations


axiom choice contents remain useful certain technical problems geometric measure theory theory banach measures charge generalization directions finitely additive signed measure see also abelian von neumann algebra almost everywhere carath odory 's extension theorem content measure theory fubini 's theorem fatou 's lemma fuzzy measure theory geometric measure theory hausdorff measure inner measure lebesgue integration lebesgue measure lorentz space lifting theory measurable cardinal measurable function minkowski content outer measure product measure pushforward measure regular measure vector measure valuation measure theory volume form references bibliography robert g bartle


''the elements integration lebesgue measure'' wiley interscience chapter iii r dudley ''real analysis probability'' cambridge university press second edition federer herbert geometric measure theory die grundlehren der mathematischen wissenschaften band springer verlag new york inc new york xiv pp h fremlin '' http www essexacuk maths people fremlin mthtm measure theory '' torres fremlin r duncan luce louis narens measurement theory ''the new palgrave dictionary economics'' v pp nbsp e munroe ''introduction measure integration'' addison wesley shilov g e gurevich b l ''integral measure derivative unified


approach'' richard silverman trans dover publications emphasizes daniell integral external links https vannevareceuwedu techsite papers documents uweetr pdf tutorial measure theory dummies


used management differentiate continued delivery goods services adapting goods services meet changing needs customers see trend term management may also refer people manage organization '''managers''' people study management colleges universities major degrees management include bachelor commerce bcom bachelor business administration bba master business administration mba master management msm mim public sector master public administration mpa degree individuals aim become management specialists experts management researchers


professors may complete doctor management dm doctor business administration dba phd business administration management recently movement evidence based management larger organizations generally three hierarchical levels managers pyramid structure senior managers members board directors chief executive officer ceo president organization set strategic goals organization make decisions overall organization operate senior managers generally executive level professionals provide direction middle management directly indirectly


report middle managers examples would include branch managers regional managers department managers section managers provide direction front line managers middle managers communicate strategic goals senior management front line managers lower managers supervisors front line team leaders oversee work regular employees volunteers voluntary organizations provide direction work smaller organizations manager may much wider scope may perform several roles even roles commonly observed large organization social scientists study management academic


discipline investigating areas social organization organizational adaptation organizational leadership etymology english verb manage roots xv century french verb 'mesnager' often referred equestrian language hold hand reins horse also italian term ''maneggiare'' handle especially tools horse possible spanish ''manejar'' also mean rule horses three terms derive two latin words ''manus'' hand ''agere'' act french word housekeeping ''m nagerie'' derived ''m nager'' keep house compare ''m nage'' household also


encompasses taking care domestic animals ''m nagerie'' french translation xenophon 's famous book ''oeconomicus'' household matters husbandry french word ''mesnagement'' ''m nagement'' influenced semantic development english word ''management'' th th centuries definitions views definition scope management include henri fayol stated manage forecast plan organise command co ordinate control ref name gulshan ref fredmund malik defines management transformation resources utility management included one factors production


along machines materials money ghislain deslandes defines management vulnerable force pressure achieve results endowed triple power constraint imitation imagination operating subjective interpersonal institutional environmental levels peter drucker saw basic task management twofold marketing innovation nevertheless innovation also linked marketing product innovation central strategic marketing issue drucker identifies marketing key essence business success management marketing generally understood two different branches business administration knowledge theoretical scope management involves identifying mission


objective procedures rules manipulation human capital enterprise contribute success enterprise scholars focused management individual organizational inter organizational relationships implies effective communication enterprise environment opposed physical mechanical mechanism implies human motivation implies sort successful progress system outcome management manipulation mechanism machine automated program herding animals occur either legal illegal enterprise environment individual 's perspective management


need seen solely enterprise point view management essential function improving one 's life relationships management therefore everywhere wider range application communication positive endeavor two main aspects either enterprise independent pursuit plans measurements motivational psychological tools goals economic measures profit etc may may necessary components management first one views management functionally measuring quantity adjusting plans meeting goals applies even situations planning


take place perspective henri fayol considers management consist five functions planning forecasting organizing commanding coordinating controlling another way thinking mary parker follett allegedly defined management art getting things done people described management philosophy critics however find definition useful far narrow phrase management managers occurs widely suggesting difficulty defining management without circularity shifting nature definitions connection managerial practices existence managerial cadre


managers lowest level management manage work non managerial individuals directly involved production creation organization 's products first line managers often called supervisors may also called line managers office managers even foremen middle managers include levels management first line level top level organization managers manage work first line managers may titles department head project leader plant manager division manager top managers responsible making organization wide decisions establishing plans goals


affect entire organization individuals typically titles executive vice president president managing director chief operating officer chief executive officer chairman board managers classified hierarchy authority perform different tasks many organizations number managers every level resembles pyramid level explained specifications different responsibilities likely job titles top top senior layer management consists board directors including non executive directors executive directors independent directors president vice president ceos members


c level executives different organizations various members c suite may include chief financial officer chief technology officer responsible controlling overseeing operations entire organization set tone top develop strategic plans company policies make decisions overall direction organization addition top level managers play significant role mobilization outside resources senior managers accountable shareholders general public public bodies oversee corporations similar organizations members senior management may


serve public face organization may make speeches introduce new strategies appear marketing board directors typically primarily composed non executives owe fiduciary duty shareholders closely involved day day activities organization although varies depending type eg public versus private size culture organization directors theoretically liable breaches duty typically insured directors officers liability insurance fortune directors estimated spend hours per week board duties


median compensation board sets corporate strategy makes major decisions major acquisitions hires evaluates fires top level manager chief executive officer ceo ceo typically hires positions however board involvement hiring positions chief financial officer cfo increased survey ceos directors public private companies found top weaknesses ceos mentoring skills board engagement companies never evaluated ceo board may also certain employees eg


internal auditors report directly hire independent contractors example board audit committee typically selects auditor helpful skills top management vary type organization typically include broad understanding competition world economies politics addition ceo responsible implementing determining within board 's framework broad policies organization executive management accomplishes day day details including instructions preparation department budgets procedures schedules appointment middle level executives department managers coordination departments media governmental relations shareholder communication middle


consist general managers branch managers department managers accountable top management department 's function devote time organizational directional functions roles emphasized executing organizational plans conformance company 's policies objectives top management define discuss information policies top management lower management importantly inspire provide guidance lower level managers towards better performance middle management midway management categorized organization secondary senior management deepest levels


supervisors section leaders forepersons team leaders focus controlling directing regular employees usually responsible assigning employees' tasks guiding supervising employees day day activities ensuring quality quantity production service making recommendations suggestions employees work channeling employee concerns cannot resolve mid level managers administrators first level front line managers also act role models employees types work front line managers may also tasks employees least time


example restaurants front line managers also serve customers busy period day front line managers typically provide training new employees basic supervision motivation performance feedback guidance front line managers may also provide career planning employees aim rise within organization training colleges universities around world offer bachelor 's degrees graduate degrees diplomas certificates management generally within colleges business business schools faculty management also related departments increase online management education


complete degree include steve jobs bill gates mark zuckerberg however many managers executives completed type business management training bachelor commerce master business administration degree major organizations including companies non profit organizations governments require applicants managerial executive positions hold minimum bachelor 's degree field related administration management case business jobs bachelor commerce similar degree undergraduate undergraduate level common business programs bachelor business


administration bba bachelor commerce bcom typically comprise four year program designed give students overview role managers planning directing within organization course topics include accounting financial management statistics marketing strategy related areas many undergraduate degrees include study management bachelor arts degrees major business administration management bachelor public administration bpa degree designed individuals aiming work bureaucrats government jobs many colleges universities also offer certificates diplomas


obtained many universities united states mba programs provide education management leadership graduate students master 's degrees business management include master management mm master science msc business administration management typically taken students aiming become researchers professors also specialized master 's degrees administration individuals aiming careers outside business master public administration mpa degree also offered master arts public administration universities students aiming become managers


executives public service master health administration students aiming become managers executives health care hospital sector management doctorates advanced terminal degrees field business management individuals obtaining management doctorates take programs obtain training research methods statistical analysis writing academic papers need seek careers researchers senior consultants professors business administration management three main types management doctorates doctor management dm doctor business administration dba


phd business administration management doctorates business administration management available many specializations good practices management trends change fast long term trend management defined market embracing diversity rising service industry managers currently trained encourage greater equality minorities women workplace offering increased flexibility working hours better retraining innovative usually industry specific performance markers managers destined service sector trained use unique measurement techniques better worker support


charismatic leadership styles human resources finds increasingly working management training capacity help collect management data success failure management actions employees evidence based management evidence based management emerging movement use current best evidence management decision making part larger movement towards evidence based practices evidence based management entails managerial decisions organizational practices informed best available evidence ref name pfeffer ref evidence based practice based three principles published peer reviewed often management social science journals research evidence bears


whether particular management practice works judgement experience contextual management practice understand organization interpersonal dynamics situation determine risks benefits available actions preferences values affected history see management late modern sense late modernity conceptualization terms cannot pre modern history harbingers stewards others however detect management like thought among ancient sumerian traders builders pyramids ancient egypt slave owners centuries faced problems


exploiting motivating dependent sometimes unenthusiastic recalcitrant workforce many pre industrial enterprises given small scale feel compelled face issues management systematically however innovations spread arabic numerals th th centuries codification double entry book keeping provided tools management assessment planning control organisation stable members right express differences solve conflicts within one person begin organisation lasting left care many many desire


maintain weak manager follow strong one another weak one maintain authority manager seeking change established organization retain least shadow ancient customs changing workplaces industrial revolutions th th centuries military theory practice contributed approaches managing newly popular factories given scale commercial operations lack mechanized record keeping recording industrial revolution made sense owners enterprises times carry management functions


system existed' imperial bureaucracy china'' ref theorists cited ancient military texts providing lessons civilian managers example chinese general sun tzu th century bc work ''the art war'' recommends phrased modern terminology aware acting strengths weaknesses manager 's organization foe 's ref name management gomez mejia p ref writings influential chinese legalist philosopher shen buhai may considered embody rare premodern example abstract theory administration american philosopher herrlee g creel scholars find influence chinese administration


europe th century thomas taylor meadows britain 's consul guangzhou argued ''desultory notes government people china'' long duration chinese empire solely altogether owing good government consists advancement men talent merit british must reform civil service making institution meritocratic ref name bodde influenced ancient chinese imperial examination northcote trevelyan report recommended recruitment basis merit determined competitive examination candidates


solid general education enable inter departmental transfers promotion achievement rather preferment patronage purchase ref name bodde ref led implementation majesty 's civil service systematic meritocratic civil service bureaucracy like british development french bureaucracy influenced chinese system voltaire claimed chinese perfected moral science fran ois quesnay advocated economic political system modeled chinese french civil service examinations adopted late th century also heavily based general cultural studies features likened


earlier chinese model ref name rung ref various ancient medieval civilizations produced mirrors princes books aimed advise new monarchs govern plato described job specialization bc alfarabi listed several leadership traits ad examples include indian ''arthashastra'' chanakya written around bc ''the prince'' italian author niccol machiavelli c ref name management gomez mejia p written adam smith scottish moral philosopher ''the wealth nations'' discussed efficient organization work division labour ref name management gomez mejia p ref smith described changes processes could boost productivity


manufacture pins individuals could produce pins per day smith analyzed steps involved manufacture specialists enabled production pins per day ref name management gomez mejia p th century classical economists adam smith john stuart mill provided theoretical background resource allocation production economics pricing issues time innovators like eli whitney james watt matthew boulton developed elements technical production standardization quality control procedures cost accounting interchangeability parts work planning many aspects management existed pre slave based


sector us economy environment saw million people contemporary usages managed profitable quasi mass production wage slavery eclipsed chattel slavery salaried managers identifiable group first became prominent late th century large corporations began overshadow small family businesses need personnel management positions became necessary businesses grew large corporations need clerks bookkeepers secretaries managers expanded demand trained managers led college university administrators consider move forward plans create first schools business


campuses th century turn twentieth century need skilled trained managers become increasingly apparent demand occurred personnel departments began expand rapidly less one twenty manufacturing firms dedicated personnel department number grown one third formal management education became standardized colleges universities colleges universities capitalized needs corporations forming business schools corporate placement departments shift toward formal business education marked creation corporate elite us


quality assurance first comprehensive theories management appeared around harvard business school offered first master business administration degree mba people like henri fayol alexander church described various branches management inter relationships early th century people like ordway tead walter scott j mooney applied principles psychology management writers elton mayo mary parker follett chester barnard max weber saw called administrator bureaucrat rensis likert chris argyris born


organisation drucker went write books many vein h dodge ronald fisher thornton c fry introduced statistical techniques management studies patrick blackett worked development applied mathematics science operations research initially military operations operations research sometimes known management science distinct taylor 's scientific management attempts take scientific approach solving decision problems apply directly multiple management problems particularly areas logistics operations later th century developments include theory constraints introduced


management objectives systematised engineering early six sigma management walking around viable system model various information technology driven theories agile software development named well group management theories cog 's ladder notion thriving chaos general recognition managers class solidified th century gave perceived practitioners art science management certain amount prestige way opened popularised systems management ideas peddle wares context many management


fads may pop psychology scientific theories management business management includes following branches financial management human resource management management cybernetics information technology management responsible management information systems marketing management operations management production management strategic management st century st century observers find increasingly difficult subdivide management functional categories way processes simultaneously involve several categories instead one tends think terms various processes tasks objects subject management branches


management theory also exist relating nonprofits government public administration public management educational management management programs related civil society organizations also spawned programs nonprofit management social entrepreneurship note many assumptions made management come attack business ethics viewpoints critical management studies anti corporate activism one consequence workplace democracy sometimes referred workers' self management become common advocated places distributing management functions among workers takes portion work however models


predate current political issue may occur naturally command hierarchy management embraces degree democratic principle long term majority workers must support management otherwise leave find work go strike despite move toward workplace democracy command control organization structures remain commonplace ' 'de facto'' organization structures indeed entrenched nature command control evident way recent layoffs conducted management ranks affected far less employees lower levels cases management even rewarded


bonuses laying lower level workers according leadership academic manfred fr kets de vries contemporary senior management team almost inevitably personality disorders nature work profitable organizations management 's primary function satisfaction range stakeholders typically involves making profit shareholders creating valued products reasonable cost customers providing great employment opportunities employees case nonprofit management one main functions keeping faith donors models management governance shareholders vote board directors


board hires senior management organizations experimented methods employee voting models selecting reviewing managers rare topics basics according fayol management operates five basic functions planning organizing coordinating commanding controlling '''planning''' deciding needs happen future generating plans action deciding advance '''organizing''' staffing making sure human nonhuman resources put place ref name peaucelle ref '''commanding''' leading determining must done situation getting people '''coordinating''' creating structure


organization 's goals accomplished '''controlling''' checking progress plans basic roles '''interpersonal''' roles involve coordination interaction employees figurehead leader '''informational''' roles involve handling sharing analyzing information nerve centre disseminator '''decision''' roles require decision making entrepreneur negotiator allocator disturbance handler skills management skills include political used build power base establish connections conceptual used analyze complex situations interpersonal used communicate motivate mentor delegate diagnostic ability visualize appropriate responses situation leadership ability communicate vision inspire people embrace vision


business requires team spirit good environment missions objectives strengths weaknesses department must analyzed determine roles achieving business 's mission forecasting method develops reliable picture business' future environment planning unit must created ensure plans consistent policies strategies aimed achieving mission objectives policies strategies planning process give mid lower level managers good idea future plans department organization framework created whereby plans


mineralogy applies principles chemistry geology physics materials science study minerals '''mineralogy''' ref name collins ref due common phonological process anticipatory assimilation especially north american also uk english nevertheless even modern descriptive uk dictionaries tend record spelling pronunciation sometimes even sound file instead assimilated pronunciation case collins dictionary ref name collins group n subject geology specializing scientific study chemistry crystal structure physical including optical properties minerals mineralized artifacts specific studies within mineralogy include

Social science
Geography
Physical geography
Mineralogy


jawahir book precious stones persian scientist al biruni german renaissance specialist georgius agricola wrote works ''de metallica'' ''on metals'' ''de natura fossilium'' ''on nature rocks'' began scientific approach subject systematic scientific studies minerals rocks developed post renaissance europe ref name needham modern study mineralogy founded principles crystallography origins geometric crystallography traced back mineralogy practiced eighteenth nineteenth centuries microscopic study rock sections invention


microscope th century ref name needham nicholas steno first observed law constancy interfacial angles also known first law crystallography quartz crystals ref name ness later generalized established experimentally jean baptiste l rom de l'islee ren ha father modern crystallography showed crystals periodic established orientations crystal faces expressed terms rational numbers later encoded miller indices ref name ness j ns jacob berzelius introduced classification minerals based chemistry rather


crystal structure ref name rafferty ref william nicol developed nicol prism polarizes light ndash studying fossilized wood henry clifton sorby showed thin sections minerals could identified optical properties using polarizing microscope ref name ness ref name rafferty james dana published first edition ''a system mineralogy'' later edition introduced chemical classification still standard ref name ness ref name rafferty x ray diffraction demonstrated max von laue developed tool analyzing crystal structure minerals father son team william


function nature prominent examples would accurate measurement prediction elastic properties minerals led new insight seismological behaviour rocks depth related discontinuities seismograms earth 's mantle end focus connection atomic scale phenomena macroscopic properties ''mineral sciences'' commonly known display perhaps overlap materials science discipline physical properties calcite carbonate mineral caco sub sub rhombohedral crystal structure aragonite orthorhombic polymorph calcite initial step


identifying mineral examine physical properties many measured hand sample classified density often given specific gravity measures mechanical cohesion hardness tenacity cleavage fracture parting macroscopic visual properties luster color streak luminescence diaphaneity magnetic electric properties radioactivity solubility hydrogen chloride ref name ness ref ref name klein ref ''hardness'' determined comparison minerals mohs scale standard set minerals numbered order increasing hardness talc diamond harder mineral scratch softer unknown


mineral placed scale minerals scratches scratch minerals calcite kyanite hardness depends significantly direction ref name manual hardness also measured absolute scale using sclerometer compared absolute scale mohs scale nonlinear ref name klein ''tenacity'' refers way mineral behaves broken crushed bent torn mineral brittle malleable sectile ductile flexible elastic important influence tenacity type chemical bond ''eg'' ionic metallic ref name manual


measures mechanical cohesion ''cleavage'' tendency break along certain crystallographic planes described quality ''eg'' perfect fair orientation plane crystallographic nomenclature ''parting'' tendency break along planes weakness due pressure twinning exsolution two kinds break occur ''fracture'' less orderly form may ''conchoidal'' smooth curves resembling interior shell ''fibrous'' ' 'splintery'' ''hackly'' jagged sharp edges ''uneven'' ref name manual mineral well crystallized also


distinctive crystal habit example hexagonal columnar botryoidal reflects crystal structure internal arrangement atoms ref name klein also affected crystal defects twinning many crystals polymorphic one possible crystal structure depending factors pressure temperature ref name ness ref name klein crystal structure perovskite crystal structure abundant mineral earth bridgmanite structure ref name sharp ref chemical formula mgfe sio sub sub red spheres oxygen blue spheres silicon green spheres magnesium iron crystal structure arrangement atoms crystal


represented lattice points repeats basic pattern called unit cell three dimensions lattice characterized symmetries dimensions unit cell dimensions represented three ''miller indices'' ref name ashcroft ref lattice remains unchanged certain symmetry operations given point lattice reflection rotation inversion rotary inversion combination rotation reflection together make mathematical object called ''crystallographic point group'' ''crystal class'' possible crystal classes addition operations displace


points translation screw axis glide plane combination point symmetries form possible space groups ref name ashcroft geology departments x ray powder diffraction equipment analyze crystal structures minerals ref name klein x rays wavelengths order magnitude distances atoms diffraction constructive destructive interference waves scattered different atoms leads distinctive patterns high low intensity depend geometry crystal sample ground powder x rays sample random distribution crystal orientations ref


name dinnebier ref powder diffraction distinguish minerals may appear hand sample example quartz polymorphs tridymite cristobalite ref name klein isomorphous minerals different compositions similar powder diffraction patterns main difference spacing intensity lines example halite crystal structure space group ''fm m'' structure shared sylvite periclase bunsenite galena alabandite chlorargyrite osbornite ref name manual ref chemical elements portable micro x ray fluorescence machine minerals chemical elements including sulfur copper silver gold vast majority


compounds classical method identifying composition ''wet chemical analysis'' involves dissolving mineral acid hydrochloric acid elements solution identified using colorimetry volumetric analysis gravimetric analysis ref name manual since chemistry analysis done using instruments one atomic absorption spectroscopy similar wet chemistry sample must still dissolved much faster cheaper solution vaporized absorption spectrum measured visible ultraviolet range ref name manual techniques x ray fluorescence electron microprobe analysis


atom probe tomography optical emission spectrography ref name manual optical photomicrograph olivine adcumulate archaean komatiite agnew western australia addition macroscopic properties colour lustre minerals properties require polarizing microscope observe transmitted light light passes air vacuum transparent crystal reflected surface refracted latter bending light path occurs speed light changes goes crystal snell 's law relates bending angle refractive index


ratio speed vacuum speed crystal crystals whose point symmetry group falls cubic system ''isotropic'' index depend direction crystals ''anisotropic'' light passing broken two plane polarized rays travel different speeds refract different angles ref name manual polarizing microscope similar ordinary microscope two plane polarized filters ''polarizer'' sample analyzer polarized perpendicular light passes successively polarizer sample analyzer


presence absence lines liquids different indices index crystal estimated usually within ref name manual systematic hanksite na sub sub k sub sub sub sub co sub sub sub sub cl one minerals considered carbonate sulfate systematic mineralogy identification classification minerals properties historically mineralogy heavily concerned taxonomy rock forming minerals international mineralogical association formed commission new minerals mineral names rationalize nomenclature regulate introduction new names july merged commission classification


minerals form commission new minerals nomenclature classification named unnamed minerals discovered year ''manual mineralogy'' places minerals following classes native elements sulfides sulfosalts oxides hydroxides halides carbonates nitrates borates sulfates chromates molybdates tungstates phosphates arsenates vanadates silicates ref name manual formation environments environments mineral formation growth highly varied ranging slow crystallization high temperatures pressures igneous melts deep within earth 's crust low temperature precipitation saline brine


isotopic studies determine things growth forms living plants animals well things like original mineral content fossils new approach mineralogy called mineral evolution explores co evolution geosphere biosphere including role minerals origin life processes mineral catalyzed organic synthesis selective adsorption organic molecules mineral surfaces ref name bbc ref mineral ecology several researchers began develop mineral evolution database ref name needs ref database integrates crowd sourced site mindatorg mineral locality pairs official ima list


approved minerals age data geological publications database makes possible apply statistics answer new questions approach called ''mineral ecology'' one question much mineral evolution deterministic much result chance factors deterministic chemical nature mineral conditions stability mineralogy also affected processes determine planet 's composition paper robert hazen others analyzed number minerals involving element function abundance


found earth known minerals elements power law relationship moon minerals elements based much smaller sample essentially relationship implies given chemical composition planet one could predict common minerals however distribution long tail minerals found one two locations model predicts thousands mineral species may await discovery formed lost erosion burial processes


implies role chance formation rare minerals occur another use big data sets network theory applied dataset carbon minerals revealing new patterns diversity distribution analysis show minerals tend coexist conditions geological physical chemical biological associated information used predict look new deposits even new mineral species id plate opposite p ref uses minerals essential various needs within human society minerals used ores essential components


metal products used various commodities machinery essential components building materials limestone marble granite gravel glass plaster cement etc ref name ramsdell ref minerals also used fertilizers enrich growth agricultural crops small collection mineral samples cases collecting mineral collecting also recreational study collection hobby clubs societies representing field museums smithsonian national museum natural history hall geology gems minerals natural history museum los angeles county carnegie museum natural historythe natural history museum london private


mim mineral museum beirut lebanon popular collections mineral specimens permanent display see also list minerals list minerals recognized international mineralogical association list mineralogists list publications mineralogy mineral collecting mineral physics metallurgy petrology notes references reading external links http wwwmineralogyeu virtual museum history mineralogy associations http wwwamfedorg american federation mineral societies http sfmc frorg french society mineralogy crystallography https webarchiveorg web http wwwgeosocietyorg geological society america http wwwdmg homeorg german mineralogical society http wwwobsuniv bpclermontfr ima international mineralogical association http wwwsocminpetit italian mineralogical petrological society http mineralogicalassociationca mineralogical association canada


'''meteorology''' branch atmospheric sciences include atmospheric chemistry atmospheric physics major focus weather forecasting study meteorology dates back millennia though significant progress meteorology begin th century th century saw modest progress field weather observation networks formed across broad regions prior attempts prediction weather depended historical data elucidation laws physics particularly development computer allowing automated solution great many equations

Social science
Geography
Physical geography
Meteorology


scales used describe predict weather local regional global levels meteorology climatology atmospheric physics atmospheric chemistry sub disciplines atmospheric sciences meteorology hydrology compose interdisciplinary field hydrometeorology interactions earth 's atmosphere oceans part coupled ocean atmosphere system meteorology application many diverse fields military energy production transport agriculture construction word ''meteorology'' ancient greek ''met ros'' ''meteor'' '' logia'' '' logy'' meaning study things high air history parhelion sundog savoie ability


predict rains floods based annual cycles evidently used humans least time agricultural settlement earlier early approaches predicting weather based astrology practiced priests cuneiform inscriptions babylonian tablets included associations thunder rain chaldeans differentiated halos ref name ref ancient indian upanishads contain mentions clouds seasons ref name imd ref samaveda mentions sacrifices performed certain phenomena noticed ref name var hamihira 's classical work ''brihatsamhita'' written ad ref name imd provides evidence weather observation bc


called 'swooping bolts' swoop upon earth lightning sometimes smoky called 'smoldering lightning sometimes darts quickly along said ''vivid'' times travels crooked lines called ''forked lightning'' swoops upon object called 'swooping lightning' greek scientist theophrastus compiled book weather forecasting called ''book signs'' work theophrastus remained dominant influence study weather weather forecasting nearly years ad pomponius mela


drop falling rain form small sphere form meant rainbow produced light interacting raindrop roger bacon first calculate angular size rainbow stated rainbow summit appear higher degrees horizon late th century early th century kam l al n al f ris theodoric freiberg first give correct explanations primary rainbow phenomenon theoderic went also explained secondary rainbow edmund halley


system classifying wind speeds near end th century first cloud atlases published including ''international cloud atlas'' remained print ever since april launch first successful weather satellite tiros marked beginning age weather information became available globally atmospheric composition research blaise pascal rediscovered atmospheric pressure decreases height deduced vacuum atmosphere daniel bernoulli published ''hydrodynamics'' initiating kinetic theory gases established basic laws theory gases


joseph black discovered ice absorbs heat without changing temperature melting black 's student daniel rutherford discovered nitrogen called ''phlogisticated air'' together developed phlogiston theory antoine lavoisier discovered oxygen developed explanation combustion lavoisier 's essay reflexions sur le phlogistique deprecates phlogiston theory proposes caloric theory sir john leslie observed matte black surface radiates heat effectively polished surface suggesting importance black body radiation john dalton defended caloric theory ''a


first written european account hurricane edmund halley presented systematic study trade winds monsoons identified solar heating cause atmospheric motions ''ideal'' explanation global circulation study trade winds written george hadley benjamin franklin prevented seeing lunar eclipse hurricane decided cyclones move contrary manner winds periphery ref name dorst ref understanding kinematics exactly rotation earth affects airflow partial first


gaspard gustave coriolis published paper energy yield machines rotating parts waterwheels ref name corps ref william ferrel proposed existence circulation cell mid latitudes air within deflected coriolis force resulting prevailing westerly winds late th century motion air masses along isobars understood result large scale interaction pressure gradient force deflecting force deflecting force named coriolis effect world war group meteorologists


norway led vilhelm bjerknes developed norwegian cyclone model explains generation intensification ultimate decay life cycle mid latitude cyclones introduced idea fronts sharply defined boundaries air masses ref name norcycmod ref group included carl gustaf rossby first explain large scale atmospheric flow terms fluid dynamics tor bergeron first determined rain forms jacob bjerknes observation networks weather forecasting cloud classification altitude occurrence alexander keith johnston hyetographic rain map europe also published part


physical atlas late th century first half th century range meteorological instruments invented thermometer barometer hydrometer well wind rain gauges natural philosophers started using instruments systematically record weather observations scientific academies established weather diaries organised observational networks ref name modscience ref ferdinando ii de medici established first ''weather observing'' network consisted meteorological stations florence cutigliano vallombrosa bologna parma milan innsbruck osnabr ck paris warsaw collected data sent florence regular time intervals


robert hooke royal society london sponsored networks weather observers hippocrates' treatise ''airs waters places'' linked weather disease thus early meteorologists attempted correlate weather patterns epidemic outbreaks climate public health ref name modscience age enlightenment meteorology tried rationalise traditional weather lore including astrological meteorology also attempts establish theoretical understanding weather phenomena edmond halley george hadley tried explain trade winds reasoned rising mass heated equator air replaced inflow cooler air


high latitudes flow warm air high altitude equator poles turn established early picture circulation frustration lack discipline among weather observers poor quality instruments led early modern nation states organise large observation networks thus end th century meteorologists access large quantities reliable weather data ref name modscience electromagnetic telegraph created baron schilling arrival electrical telegraph afforded first time practical method quickly gathering surface


early understandings jet streams charles kenneth mackinnon douglas known 'ckm' douglas read ley 's papers death carried early study weather systems nineteenth century researchers meteorology drawn military medical backgrounds rather trained dedicated scientists united kingdom government appointed robert fitzroy new office ''meteorological statist board trade'' task gathering weather observations sea fitzroy 's office became united kingdom meteorological office second oldest national meteorological service world central institution meteorology


geodynamics zamg austria founded oldest weather service world first daily weather forecasts made fitzroy 's office published ''the times'' newspaper following year system introduced hoisting storm warning cones principal ports gale expected next years many countries established national meteorological services india meteorological department established follow tropical cyclone monsoon finnish meteorological central office formed part magnetic observatory helsinki university japan 's tokyo meteorological observatory


forerunner japan meteorological agency began constructing surface weather maps united states weather bureau established united states department agriculture australian bureau meteorology established meteorology act unify existing state meteorological services ref name abc ref numerical weather prediction meteorologist console ibm joint numerical weather prediction unit c norwegian scientist vilhelm bjerknes first argued paper ''weather forecasting problem mechanics physics'' possible forecast weather calculations based upon


natural laws later th century advances understanding atmospheric physics led foundation modern numerical weather prediction lewis fry richardson published weather prediction numerical process finding notes derivations worked ambulance driver world war described small terms prognostic fluid dynamics equations govern atmospheric flow could neglected numerical calculation scheme could devised allow predictions richardson envisioned large auditorium thousands people performing calculations however sheer


number calculations required large complete without electronic computers size grid time steps used calculations led unrealistic results though numerical analysis later found due numerical instability starting numerical forecasts computers became feasible first weather forecasts derived way used barotropic single vertical level models could successfully predict large scale movement midlatitude rossby waves pattern atmospheric lows highs uk meteorological office received first computer ferranti mercury chaotic


nature atmosphere first observed mathematically described edward lorenz founding field chaos theory advances led current use ensemble forecasting major forecasting centers take account uncertainty arising chaotic nature atmosphere ref name hpcens ref mathematical models used predict long term weather earth climate models developed resolution today coarse older weather prediction models climate models used investigate long term climate shifts effects might caused human


emission greenhouse gases meteorologists '''meteorologists''' scientists study work field meteorology american meteorological society publishes continually updates authoritative electronic ''meteorology glossary'' meteorologists work government agencies private consulting research services industrial enterprises utilities radio television stations education united states meteorologists held jobs ref name bls ref although weather forecasts warnings best known products meteorologists public weather presenters radio television necessarily professional meteorologists often reporters little formal meteorological training using unregulated


titles ''weather specialist'' ''weatherman'' american meteorological society national weather association issue seals approval weather broadcasters meet certain requirements mandatory hired media equipment satellite image hurricane hugo polar low visible top image science unique sets laboratory equipment atmosphere many things qualities atmosphere measured rain observed seen anywhere anytime one first atmospheric qualities measured historically also


two accurately measured qualities wind humidity neither seen felt devices measure three sprang mid th century respectively rain gauge anemometer hygrometer many attempts made prior th century construct adequate equipment measure many atmospheric variables many faulty way simply reliable even aristotle noted work difficulty measure air sets surface measurements important data meteorologists give


snapshot variety weather conditions one single location usually weather station ship weather buoy measurements taken weather station include number atmospheric observables usually temperature pressure wind measurements humidity variables measured thermometer barometer anemometer hygrometer respectively professional stations may also include air quality sensors carbon monoxide carbon dioxide methane ozone dust smoke ceilometer cloud ceiling falling precipitation sensor flood sensor lightning sensor microphone explosions sonic booms thunder pyranometer pyrheliometer spectroradiometer ir vis uv photodiodes rain gauge snow gauge scintillation


counter background radiation fallout radon seismometer earthquakes tremors transmissometer visibility gps clock data logging upper air data crucial importance weather forecasting widely used technique launches radiosondes supplementing radiosondes network aircraft collection organized world meteorological organization remote sensing used meteorology concept collecting data remote weather events subsequently producing weather information common types remote sensing radar lidar satellites photogrammetry collects data atmosphere remote location usually stores


data instrument located radar lidar passive use em radiation illuminate specific portion atmosphere weather satellites along general purpose earth observing satellites circling earth various altitudes become indispensable tool studying wide range phenomena forest fires el ni spatial scales study atmosphere divided distinct areas depend time spatial scales one extreme scale climatology timescales hours days meteorology separates micro meso


synoptic scale meteorology respectively geospatial size three scales relates directly appropriate timescale subclassifications used describe unique local broad effects within subclasses class wikitable style border spacing px margin auto '''typical scales atmospheric motion systems''' scope col style width px type motion scope col style width px horizontal scale meter molecular mean free path sup sup minute turbulent eddies sup sup sup sup small eddies sup sup dust devils


gusts sup sup tornadoes sup sup thunderclouds sup sup fronts squall lines sup sup sup sup hurricanes sup sup synoptic cyclones sup sup planetary waves sup sup atmospheric tides sup sup mean zonal wind sup sup microscale microscale meteorology study atmospheric phenomena scale less individual thunderstorms clouds local turbulence caused buildings obstacles individual hills


modeled scale mesoscale mesoscale meteorology study atmospheric phenomena horizontal scales ranging nbsp km nbsp km vertical scale starts earth 's surface includes atmospheric boundary layer troposphere tropopause lower section stratosphere mesoscale timescales last less day multiple weeks events typically interest thunderstorms squall lines fronts precipitation bands tropical extratropical cyclones topographically generated weather systems mountain waves sea land breezes synoptic scale noaa synoptic scale weather analysis synoptic scale meteorology


predicts atmospheric changes scales nbsp km sup sup sec days time space synoptic scale coriolis acceleration acting moving air masses outside tropics plays dominant role predictions phenomena typically described synoptic meteorology include events extratropical cyclones baroclinic troughs ridges frontal zones extent jet streams typically given weather maps specific time minimum horizontal scale synoptic phenomena limited spacing surface observation stations global scale annual mean sea surface temperatures


global scale meteorology study weather patterns related transport heat tropics poles large scale oscillations importance scale oscillations time periods typically order months madden julian oscillation years el ni southern oscillation pacific decadal oscillation global scale meteorology pushes range climatology traditional definition climate pushed larger timescales understanding longer time scale global oscillations effect climate weather disturbances included


synoptic mesoscale timescales predictions numerical weather prediction main focus understanding air sea interaction tropical meteorology atmospheric predictability tropospheric stratospheric processes naval research laboratory monterey california developed global atmospheric model called navy operational global atmospheric prediction system nogaps nogaps run operationally fleet numerical meteorology oceanography center united states military many global atmospheric models run national meteorological agencies meteorological principles boundary layer meteorology boundary layer meteorology study processes air layer directly earth 's surface known atmospheric boundary layer


abl effects surface nbsp heating cooling friction nbsp cause turbulent mixing within air layer significant movement heat matter momentum time scales less day caused turbulent motions boundary layer meteorology includes study types surface atmosphere boundary including ocean lake urban land non urban land study meteorology dynamic meteorology dynamic meteorology generally focuses fluid dynamics atmosphere idea air parcel used define smallest element atmosphere ignoring discrete molecular chemical nature


atmosphere air parcel defined point fluid continuum atmosphere fundamental laws fluid dynamics thermodynamics motion used study atmosphere physical quantities characterize state atmosphere temperature density pressure etc variables unique values continuum applications weather forecasting forecast surface pressures five days future north pacific north america north atlantic ocean weather forecasting application science technology predict state atmosphere future time given location


humans attempted predict weather informally millennia formally since least th century weather forecasts made collecting quantitative data current state atmosphere using scientific understanding atmospheric processes project atmosphere evolve human endeavor based mainly upon changes barometric pressure current weather conditions sky condition forecast models used determine future conditions human input still required pick best possible forecast model base forecast upon involves pattern recognition skills teleconnections knowledge model performance


knowledge model biases chaotic nature atmosphere massive computational power required solve equations describe atmosphere error involved measuring initial conditions incomplete understanding atmospheric processes mean forecasts become less accurate difference current time time forecast made ''range'' forecast increases use ensembles model consensus help narrow error pick likely outcome ref name klaus ref ref name tbk ref variety end uses weather forecasts weather warnings important forecasts


used protect life property forecasts based temperature precipitation important agriculture therefore commodity traders within stock markets temperature forecasts used utility companies estimate demand coming days everyday basis people use weather forecasts determine wear since outdoor activities severely curtailed heavy rain snow wind chill forecasts used plan activities around events plan ahead survive aviation meteorology aviation meteorology deals impact weather air traffic management important


air crews understand implications weather flight plan well aircraft noted ''aeronautical information manual'' blockquote ''the effects ice aircraft cumulative thrust reduced drag increases lift lessens weight increases results increase stall speed deterioration aircraft performance extreme cases inches ice form leading edge airfoil less minutes takes inch ice reduce lifting power aircraft percent increases


frictional drag equal percentage'' blockquote agricultural meteorology meteorologists soil scientists agricultural hydrologists agronomists people concerned studying effects weather climate plant distribution crop yield water use efficiency phenology plant animal development energy balance managed natural ecosystems conversely interested role vegetation climate weather hydrometeorology hydrometeorology branch meteorology deals hydrologic cycle water budget rainfall statistics storms hydrometeorologist prepares issues forecasts accumulating quantitative precipitation heavy rain heavy snow highlights areas


globe program global learning observations benefit environment international environmental science education program links students teachers scientific research community effort learn environment student data collection observation http amsglossaryallenpresscom glossary glossary meteorology american meteorological society excellent reference nomenclature equations concepts advanced reader http wwwsrhnoaagov srh jetstream jetstream online school weather national weather service http wwwbomgovau lam learn meteorology australian bureau meteorology http weatheraboutcom weather guide weather tutorials news aboutcom http meteducaredu meteorology


observatory applied interdisciplinary physics oceanography physical geography greek words phrases


marine biology include everything tiny layers surface water organisms abiotic items may trapped surface tension ocean atmosphere depths oceanic trenches sometimes meters beneath surface ocean specific habitats include estuaries coral reefs kelp forests seagrass meadows surrounds seamounts thermal vents tidepools muddy sandy rocky bottoms open ocean pelagic zone solid objects rare surface water visible boundary organisms studied range microscopic phytoplankton


zooplankton huge cetaceans whales length marine ecology study marine organisms interact environment marine life vast resource providing food medicine raw materials addition helping support recreation tourism world fundamental level marine life helps determine nature planet marine organisms contribute significantly oxygen cycle involved regulation earth 's climate ref name dms ref shorelines part shaped protected marine life marine organisms even help create new


land ref name sousa ref many species economically important humans including finfish shellfish also becoming understood well marine organisms organisms linked fundamental ways human body knowledge regarding relationship life sea important cycles rapidly growing new discoveries made nearly every day cycles include matter carbon cycle air earth 's respiration movement energy ecosystems including ocean large areas beneath ocean surface still remain effectively unexplored biological oceanography


marine biology studies species live marine habitats earth 's surface covered ocean home marine life oceans average nearly four kilometers depth fringed coastlines run kilometres alt two views ocean space marine biology contrasted biological oceanography marine life field study marine biology biological oceanography biological oceanography study organisms affect affected physics chemistry geology oceanographic system biological oceanography mostly focuses


microorganisms within ocean looking affected environment affects larger marine creatures ecosystem ref name lalli parsons lalli carol timothy r parsons introduction biological oceanography introduction first edition ed tarrytown new york pergamon print ref biological oceanography similar marine biology studies ocean life different perspective biological oceanography takes bottom approach terms food web marine biology studies ocean top perspective biological oceanography mainly focuses ecosystem ocean emphasis


area occupies seven percent total ocean area open ocean habitats found deep ocean beyond edge continental shelf alternatively marine habitats divided pelagic demersal habitats pelagic habitats found near surface open water column away bottom ocean affected ocean currents demersal habitats near bottom marine habitats modified inhabitants marine organisms like corals kelp sea grasses ecosystem engineers reshape marine environment point


create habitat organisms intertidal near shore tide pools sea stars sea anemone intertidal zones areas close shore constantly exposed covered ocean 's tides huge array life found within zone shore habitats span upper intertidal zones area land vegetation takes prominence underwater anywhere daily infrequently many species scavengers living sea life washed shore many land animals also make much use


shore intertidal habitats subgroup organisms habitat bores grinds exposed rock process bioerosion estuaries estuaries shifting flows sea water fresh water estuaries also near shore influenced tides estuary partially enclosed coastal body water one rivers streams flowing free connection open sea ref name james ref estuaries form transition zone freshwater river environments saltwater maritime environments subject marine influences tides waves influx


saline water riverine influences flows fresh water sediment shifting flows sea water fresh water provide high levels nutrients water column sediment making estuaries among productive natural habitats world ref name mclusky ref reefs coral reefs form complex marine ecosystems tremendous biodiversity reefs comprise densest diverse habitats world best known types reefs tropical coral reefs exist tropical waters however reefs also exist cold water reefs built


corals calcium depositing animals usually top rocky outcrop ocean floor reefs also grow surfaces made possible create artificial reefs coral reefs also support huge community life including corals symbiotic zooxanthellae tropical fish many organisms much attention marine biology focused coral reefs el ni weather phenomenon coral reefs experienced severe mass bleaching events record vast expanses reefs across world died sea surface temperatures rose well


normal reefs recovering scientists say world 's coral reefs endangered predict global warming could exacerbate trend representative ocean animal life drawn scale within approximate depth defined ecological habitats marine microorganisms exist surfaces within tissues organs diverse life inhabiting ocean across ocean habitats ref name apprill apprill marine animal microbiomes toward understanding host microbiome interactions changing ocean ''frontiers marine science'' ''' ''' px material copied source available


https creativecommonsorg licenses creative commons attribution international license ref open ocean open ocean area deep sea beyond continental shelves open ocean relatively unproductive lack nutrients yet vast total produces primary productivity open ocean separated different zones different zones different ecologies zones vary according depth include epipelagic mesopelagic bathypelagic abyssopelagic hadopelagic zones zones vary amount light receive include photic aphotic zones much aphotic


general deep sea considered start aphotic zone point sunlight loses power transference water many life forms live depths ability create light known bio luminescence marine life also flourishes around seamounts rise depths fish sea life congregate spawn feed hydrothermal vents along mid ocean ridge spreading centers act oases opposites cold seeps places support unique biomes many new microbes lifeforms discovered


environment rather taxonomy reason marine biology encompasses organisms live marine environment also organisms whose lives revolve around sea microscopic life inhabitants largest environment earth microbial marine systems drive changes every global system microbes responsible virtually photosynthesis occurs ocean well cycling carbon nitrogen phosphorus nutrients trace elements microscopic life undersea incredibly diverse still poorly understood example role viruses marine


ecosystems barely explored even beginning st century role phytoplankton better understood due critical position numerous primary producers earth phytoplankton categorized cyanobacteria also called blue green algae bacteria various types algae red green brown yellow green diatoms dinoflagellates euglenoids coccolithophorids cryptomonads chrysophytes chlorophytes prasinophytes silicoflagellates zooplankton tend somewhat larger microscopic many protozoa zooplankton including dinoflagellates zooflagellates foraminiferans radiolarians dinoflagellates also phytoplankton distinction plants animals often breaks


small organisms zooplankton include cnidarians ctenophores chaetognaths molluscs arthropods urochordates annelids polychaetes many larger animals begin life zooplankton become large enough take familiar forms two examples fish larvae sea stars also called starfish plants algae microscopic algae plants provide important habitats life sometimes acting hiding places larval forms larger fish foraging places invertebrates algal life widespread diverse ocean microscopic photosynthetic algae contribute larger proportion world 's photosynthetic output


terrestrial forests combined niche occupied sub plants land actually occupied macroscopic algae ocean ''sargassum'' kelp commonly known seaweeds create kelp forests plants survive sea often found shallow waters seagrasses examples eelgrass ''zostera'' turtle grass ''thalassia'' plants adapted high salinity ocean environment intertidal zone also good place find plant life sea mangroves cordgrass beach grass might


grow invertebrates land invertebrates make huge portion life sea invertebrate sea life includes cnidaria jellyfish sea anemones ctenophora sea worms including phyla platyhelminthes nemertea annelida sipuncula echiura chaetognatha phoronida mollusca including shellfish squid octopus arthropoda including chelicerata crustacea porifera bryozoa echinodermata including starfish urochordata including sea squirts tunicates invertebrates backbone million species fungi species fungi known marine environments parasitic marine algae animals saprobes algae


corals protozoan cysts sea grasses wood substrata also found sea foam spores many species special appendages facilitate attachment substratum diverse range unusual secondary metabolites produced marine fungi vertebrates fish reported species fish including bony cartilaginous fish described vertebrates combined fish species live saltwater reptiles reptiles inhabit frequent sea include sea turtles sea snakes terrapins marine iguana saltwater crocodile


extant marine reptiles except sea snakes oviparous need return land lay eggs thus species excepting sea turtles spend lives near land rather ocean despite marine adaptations sea snakes prefer shallow waters nearby land around islands especially waters somewhat sheltered well near estuaries ref name sti stidworthy j snakes world grosset dunlap inc pp ref ref name ras fao ftp ftpfaoorg docrep fao e e pdf sea snakes http wwwfaoorg food agriculture organization united nations accessed august ref extinct marine


sperm whale dive prolonged periods must return surface breathe subfields marine ecosystem large thus many sub fields marine biology involve studying specializations particular animal groups phycology invertebrate zoology ichthyology subfields study physical effects continual immersion sea water ocean general adaptation salty environment effects changing various oceanic properties marine life subfield marine biology studies relationships oceans ocean life global warming


oceanography atmospheric sciences closely related field distribution factors active research topic marine biology discover map life cycles various species spend time technologies aid discovery include pop satellite archival tags acoustic tags variety data loggers marine biologists study ocean currents tides many oceanic factors affect ocean life forms including growth distribution well recently become technically feasible advances gps newer underwater visual devices ocean life breeds


specific places nests others spends time juveniles still others maturity yet others scientists know little many species spend different parts life cycles especially infant juvenile years example still largely unknown juvenile sea turtles year sharks travel recent advances underwater tracking devices illuminating know marine organisms live great ocean depths information pop satellite archival tags give aids certain time year fishing closures development marine protected


amount knowledge gained life exists oceans world many voyages contributed significantly pool knowledge among significant voyages charles darwin came theories evolution formation coral reefs another important expedition undertaken hms ''challenger'' findings made unexpectedly high species diversity among fauna stimulating much theorizing population ecologists varieties life could maintained thought hostile environment era important


history marine biology naturalists still limited studies lacked technology would allow adequately examine species lived deep parts oceans creation marine laboratories important allowed marine biologists conduct research process specimens expeditions oldest marine laboratory world station biologique de roscoff established france united states scripps institution oceanography dates back prominent woods hole oceanographic institute founded development technology


sound navigation ranging scuba diving gear submersibles remotely operated vehicles allowed marine biologists discover explore life deep oceans thought exist see also acoustic ecology aquaculture bathymetry biological oceanography freshwater biology modular ocean model oceanic basin oceanic climate phycology world ocean atlas lists glossary ecology index biology articles large marine ecosystem list ecologists list marine biologists list marine ecoregions wwf outline biology outline ecology references references morrissey j sumich j https booksgooglecom booksid cm kcc printsec frontcover dq introduction biology marine life hl en sa x ei xgpwvmdqduxumgxo kaca ved cb q aewaa v onepage q introduction biology marine life f false ''introduction


biology marine life'' jones bartlett publishers mladenov philip v marine biology short introduction nd edn oxford online edn short introductions online feb http dxdoiorg actrade accessed jun external links http oceansiedu smithsonian ocean portal http wwwmcsukorg marine conservation society http wwwwileyonlinelibrarycom journal maec marine ecology evolutionary perspective http onlinelibrarywileycom doi mae issue issuetoc free special issue marine biology time space https wwwyoutubecom watchv igrjjumlmge creatures deep ocean ''national geographic'' documentary http wwwexplorisorguk exploris http contentlibwashingtonedu fishweb indexhtml freshwater marine image bank university washington library http wwwmarinetrainingeu marine training portal portal grouping training initiatives


field marine biology biological oceanography fisheries science oceanographical terminology


maritime archaeologist lighthouse archaeological maritime program st augustine florida recording ship 's bell discovered th century storm wreck '''maritime archaeology''' also known '''marine archaeology''' discipline within archaeology whole specifically studies human interaction sea lakes rivers study associated physical remains vessels shore side facilities port related structures cargoes human remains submerged landscapes specialty within maritime archaeology nautical archaeology studies ship construction use archaeology whole maritime archaeology practised within historical

Social science
Archaeology
Maritime archaeology


industrial prehistoric periods associated discipline one lies within archaeology underwater archaeology studies past submerged remains maritime interest example prehistoric era would remains submerged settlements deposits lying water despite dry land sea levels lower study submerged aircraft lost lakes rivers sea example historical industrial modern era another example remains discovered potential medieval bridges connecting islands


lake mainland many specialist sub disciplines within broader maritime underwater archaeological categories emerged recent years maritime archaeological sites often result shipwrecks sometimes seismic activity thus represent moment time rather slow deposition material accumulated period years case port related structures piers wharves docks jetties objects lost thrown structures extended periods time fact led shipwrecks often described media popular accounts


'time capsules' archaeological material sea underwater environments typically subject different factors artifacts land however terrestrial archaeology survives investigated modern archaeologists often tiny fraction material originally deposited feature maritime archaeology despite material lost occasional rare examples substantial survival great deal learned due difficulties often experienced accessing sites archaeology community see maritime archaeology separate


discipline concerns shipwrecks requiring specialized skills underwater archaeologist others value integrated approach stressing nautical activity economic social links communities land archaeology archaeology matter study conducted required mastering skills specific environment work occurs lake murray south carolina ft fresh water seen side scan sonar imagery using humminbird c side imaging system integrating land sea industrial era travel


water often easier land result marine channels navigable rivers sea crossings formed trade routes historic ancient civilisations example mediterranean sea known romans inner sea roman empire spread around coasts historic record well remains harbours ships cargoes testify volume trade crossed later nations strong maritime culture united kingdom netherlands denmark portugal spain able establish colonies continents wars


fought sea control important resources material cultural remains discovered maritime archaeologists along former trade routes combined historical documents material cultural remains found land understand economic social political environment past late maritime archaeologists examining submerged cultural remains china india korea asian nations preservation material underwater mary rose october significant differences survival archaeological material depending whether site wet


dry nature chemical environment presence biological organisms dynamic forces present thus rocky coastlines especially shallow water typically inimical survival artifacts dispersed smashed ground effect currents surf possibly always leaving artifact pattern little wreck structure saltwater particularly inimical iron artefacts including metal shipwrecks sea organisms readily consume organic material wooden shipwrecks hand thousands potential archaeological


sites destroyed grossly eroded natural processes occasionally sites survive exceptional preservation related collection artifacts example collection survival instance largely due remains buried sediment many examples sea bed provides extremely hostile environment submerged evidence history one notable though relatively young wreck deep water calcium starved concretion occur appears strong relatively intact though indications already incurred irreversible degradation


steel iron hull degradation inevitably continues data forever lost objects' context destroyed bulk wreck centuries completely deteriorate floor atlantic ocean comparative evidence shows iron steel ships especially highly oxygenated environment continue degrade continue engines machinery project much sea floor remains even passage time iron steel hull often fragile


remaining metal within layer concretion corrosion products found subjected program attempted ''in situ'' preservation example deterioration vessel progressed rate rescue turret undertaken lest nothing saved wreck wrecks lost natural obstacles navigation risk smashed subsequent wrecks sunk hazard deliberately destroyed present hazard navigation even deep water commercial activities pipe laying operations deep


sea trawling place wreck risk wreck ''mardi gras'' shipwreck sunk gulf mexico water shipwreck lay forgotten bottom sea discovered oilfield inspection crew working okeanos gas gathering company oggc large pipelines crush sites render remnants inaccessible pipe dropped ocean surface substrate thousands feet trawl nets snag tear superstructures separate artifacts context swedish warship


foundered sank maiden voyage salvaged permanent display vasa museum stockholm wrecks archaeological sites preserved generally survived dynamic nature sea bed result artifacts becoming rapidly buried sediments sediments provide anaerobic environment protects degradation wet environments whether land form peat bogs wells underwater particularly important survival organic material wood leather fabric horn cold


absence light also aid survival artifacts little energy available either organic activity chemical reactions salt water provides greater organic activity freshwater particular shipworm terredo navalis lives salt water best preservation absence sediments found cold dark waters great lakes north america low salinity baltic sea ''vasa'' preserved land surface continuously reused societies sea bed largely inaccessible advent submarines


scuba equipment remotely operated underwater vehicles rovs twentieth century salvagers operated much earlier times much material beyond reach anyone thus ''mary rose'' subject salvage sixteenth century later large amount material buried sediments remained found maritime archaeologists twentieth century preservation situ assured material survived underwater recovered land typically unstable state preserved using highly specialised conservation processes


wooden structure ''mary rose'' individual artifacts undergoing conservation since recovery provides example relatively recent metal wreck extensive conservation necessary preserve hull hull remains intact machinery remains inoperable engine recovered saline environment century underwater presently considered somewhat anomalous two decades treatment turned hand challenge modern archaeologist consider whether ''in situ'' preservation


recovery conservation land preferable option face fact preservation form archaeological record feasible site discovered typically subjected disturbance factors caused survival first place example covering sediment removed storms action man active monitoring deliberate protection may mitigate rapid destruction making ''in situ'' preservation option long term survival never guaranteed many sites costs


great either active measures ensure ''in situ'' preservation provide satisfactory conservation recovery even cost proper complete archaeological investigation may great enable occur within timescale ensures archaeological record made data inevitably lost submerged sites pre historic landscapes maritime archaeology studies prehistorical objects sites changes climate geology underwater bodies water fresh saline important sources food people long existed


sites coast western europe grotto cosquer reached diving cave entrances underwater though upper portions caves flooded historic sites throughout history seismic events times caused submergence human settlements remains catastrophes exist world sites alexandria port royal form important archaeological sites shipwrecks archaeological research follow multiple themes including evidence final catastrophe structures landscape catastrophe culture


economy formed part unlike wrecking ship destruction town seismic event take place many years may evidence several phases damage sometimes rebuilding coastal foreshore maritime sites underwater many structures margin land water provide evidence human societies past deliberately created access bridges walkways structures remain exploitation resources dams fish traps


nautical remains include early harbours places ships built repaired end life ships often beached valuable easily accessed timber often salvaged leaving frames bottom planking archaeological sites also found foreshore today would dry land constructed example site seahenge bronze age timber circle ships shipwrecks russian submarine ''akula'' found near hiiumaa estonia archaeology shipwrecks divided three tier


hierarchy first tier considers wrecking process ship break ship sink bottom remains ship cargo surrounding environment evolve time second tier studies ship machine military economic system third tier consists archaeology maritime cultures nautical technology naval warfare trade shipboard societies studied consider important tier ships boats necessarily wrecked


deliberately abandoned scuttled beached many abandoned vessels extensively salvaged bronze age earliest boats discovered date bronze age constructed hollowed logs sewn planks vessels discovered preserved sediments underwater waterlogged land sites http newsbbccouk hi wales south west stm discovery canoe near st botolphs examples sewn plank boats include found north ferriby http wwwarchaeologycouk ca timeline prehistory dover doverhtm dover bronze age boat displayed dover museum https webarchiveorg web http wwwdovergovuk museum boat may evolution boats made sewn hides


highly unlikely hide boats could survived ships wrecked sea probably survived although remains cargo particularly bronze material discovered salcombe b site close collection artefacts sea bed may imply artefacts ship even remains actual vessel late bronze age ships uluburun shipwreck discovered mediterranean constructed edge joined planks shipbuilding technology continued classical period maritime archaeology region pacific try pot


th century whaling ship wrecked french frigate shoals pacific ocean divers explored wreck site pearl hermes atoll example maritime archaeology pacific ocean discovery wreck ''two brothers'' discovered team marine archaeologists working expedition national oceanic atmospheric administration noaa identity ship immediately known called shark island whaler ship 's identification ''two brothers'' announced noaa february th anniversary sinking ref


name gleasonnantucket wreck first discovery wrecked nantucket whaling ship ref name noaa news ref ref name gleasonnantucket ref mediterranean area mediterranean area maritime archaeologists investigated several ancient cultures notable early iron age shipwrecks include two phoenician ships c bc foundered gaza cargoes wine amphoras crew us navy deep submergence research submarine nr discovered sites team led robert ballard harvard university archaeology professor lawrence stager investigated wrecks extensive research carried mediterranean aegean


coastlines turkey complete excavations performed several wrecks classical hellenistic byzantine ottoman periods maritime archaeological studies italy illuminate naval maritime activities etruscans greek colonists romans nd century bc roman fleet ruled mediterranean actively suppressed piracy pax romana seaborne trade increased significantly throughout region though sailing safest fastest efficient method transportation ancient world fractional percentage voyages ended shipwreck significantly increased sea traffic roman era came corresponding