the-french-artist/wikipedia_20220301.simple_sentence_embeddings huggingface dataset:
First law of thermodynamics 
 This means that anything that uses energy is changing the energy from one kind of energy to another.
First law of thermodynamics 
 Another example:  In the Sun (or any star), nuclear fusion changes mass into heat and light (electromagnetic radiation), which travels to Earth and is used by plants to create food (chemical energy) via photosynthesis, which can be eaten by animals allowing them to move (kinetic energy).
First law of thermodynamics 
 This is why perpetual motion machines do not exist and could never exist; it would break a fundamental law of physics.
First law of thermodynamics 
 Examples of forms of energy in classical mechanics include heat, light, kinetic (movement) or potential energy.
First law of thermodynamics 
 However, in modern physics it is considered that there are only two types of energy - mass and kinetic energy, although this may not be helpful to those not familiar with more complex physics.
First law of thermodynamics 
 James Prescott Joule was the first person who found out by experiments that heat and work are convertible.
First law of thermodynamics 
 The first explicit statement of the first law of thermodynamics was given by Rudolf Clausius in 1850: "There is a state function E, called 'energy', whose differential equals the work exchanged with the surroundings during an adiabatic process."
First law of thermodynamics 
 In thermodynamics and engineering, it is natural to think of the system as a heat engine which does work on the surroundings, and to state that the total energy added by heating is equal to the sum of the increase in internal energy plus the work done by the system.
First law of thermodynamics 
 Hence  is the amount of energy lost by the system due to work done by the system on its surroundings.
First law of thermodynamics 
 During the portion of the thermodynamic cycle where the engine is doing work,  is positive, but there will always be a portion of the cycle where  is negative, e.g., when the working gas is being compressed.
First law of thermodynamics 
 Because of this ambiguity, it is very important in any discussion involving the first law to explicitly establish the sign convention in use.
Conservation of energy 
 In physics, the conservation of energy is that energy can not be created or destroyed, it can only be changed from one form to another, such as when electrical energy is changed into heat energy.
Conservation of energy 
 Formally, it says that the total amount of energy in an isolated system remains constant, although it may change forms, e.g. friction turns kinetic energy into thermal energy.
Conservation of energy 
 In thermodynamics, the first law of thermodynamics is a statement of the conservation of energy for thermodynamic systems.
Conservation of energy 
 From a mathematical point of view, the energy conservation law is a consequence of the shift symmetry of time; energy conservation is a result of the empirical fact that the laws of physics do not change with time itself.
Conservation of energy 
 Ancient philosophers as far back as Thales of Miletus had the idea that there is some underlying substance of which everything is made.
Conservation of energy 
 But that is not the same as our concept of "mass-energy" today (for example, Thales thought the underlying substance was water).
Conservation of energy 
 This can be described (in modernized language) as conservatively converting potential energy to kinetic energy and back again.
Conservation of energy 
 However, Galileo did not explain the process in modern terms and had not understood the modern concept either.
Conservation of energy 
 The German Gottfried Wilhelm Leibniz during 1676-1689 attempted a mathematical formulation of the kind of energy which is connected with motion (kinetic energy).
Conservation of energy 
 The principle represents an accurate statement of the approximate conservation of kinetic energy in situations where there is no friction.
Conservation of energy 
 Meanwhile, in 1843 James Prescott Joule independently discovered the mechanical equivalent in a series of experiments.
Conservation of energy 
 In the most famous, now called the "Joule apparatus", a descending weight attached to a string caused a paddle immersed in water to rotate.
Conservation of energy 
 He showed that the gravitational potential energy lost by the weight in descending was approximately equal to the thermal energy (heat) gained by the water by friction with the paddle.
Conservation of energy 
 Over the period 1840-1843, similar work was carried out by engineer Ludwig A. Colding though it was little-known outside his native Denmark.
Differences between butterflies and moths 
 Butterflies are often put in the suborder  Rhopalocera, which includes Papilionoidea (true butterflies), the Hesperiidae (skippers), and the Hedylidae (butterfly moths).
Differences between butterflies and moths 
 However, moths do look and behave rather different from butterflies, which explains why people came to call them by a different name.
Differences between butterflies and moths 
 This distinction is the basis for the earliest taxonomic divisions in the Lepidoptera  the Rhopalocera ("clubbed horn", the butterflies) and the Heterocera ("varied horn", the moths).
Differences between butterflies and moths 
 There are, however, exceptions to this rule and a few moths (the family Castniidae) have clubbed antennae.
Differences between butterflies and moths 
 Some butterflies, like Pseudopontia paradoxa from the forests of central Africa, lack the clubbed ends.
Differences between butterflies and moths 
 Many moths have a frenulum or wing coupling physically attaching upper and lower parts of their wings together.
Differences between butterflies and moths 
 Gypsy moths sometimes form butterfly-style pupae, hanging on twigs or tree bark, although usually they create flimsy cocoons out of silk strands and a few leaves, partially exposing the chrysalis.
Differences between butterflies and moths 
 A few Skipper butterfly larvae also make crude cocoons in which they pupate, exposing the pupa a bit.
Differences between butterflies and moths 
 The Parnassius butterfly larvae make a flimsy cocoon for pupation and they pupate near the ground surface between debris.
Differences between butterflies and moths 
 Nocturnal moths on the other hand are usually plain brown, grey, white or black and often with obscuring patterns of zigzags or swirls which help camouflage them as they rest during the day.
Differences between butterflies and moths 
 This difference is possibly due to the need for moths to conserve heat during the cooler nights whereas butterflies are able to absorb sunlight.
Differences between butterflies and moths 
 Most moths are nocturnal or crepuscular (active at night) while most butterflies are diurnal (active at daytime).
Differences between butterflies and moths 
 There are however exceptions, including the diurnal gypsy moth and the spectacular "Uraniidae" or Sunset moths.
Differences between butterflies and moths 
 Butterflies frequently fold their wings above their backs when they are perched although they will occasionally "bask" with their wings spread for short periods.
Differences between butterflies and moths 
 However some butterflies, like the skippers, may hold their wings either flat or folded or even in-between (the so-called "jet plane" position) when perched.
Differences between butterflies and moths 
 Most moths also occasionally fold their wings above their backs when they are in a certain spot (like when there is no room to fully spread their wings).
Differences between butterflies and moths 
 A sometimes confusing family can be the "Geometridae" (such as the winter moth) because the adults often rest with their wings folded vertically.
Differences between butterflies and moths 
 These moths have thin bodies and large wings like many butterflies but may be distinguished easily by structural differences in their antennae (e.g. bipectinate).
Monophyly 
 The aim of this is to make biological classification fit what we know about the way organisms evolved.
Monophyly 
 If a group contains the common ancestor, but leaves out some of its descendants, it is called paraphyletic.
Monophyly 
 All living things on this planet are thought, on the basis of DNA analysis, to be monophyletic, that is, to have one origin, not many.
Monophyly 
 Example: all species in the genus Homo have come from the same ancestral form in the family Hominidae, and no other descendants are known.
Monophyly 
 If, on the other hand, it were discovered that Homo habilis had developed from a different ancestor from Homo sapiens, and this ancestor were not included in the genus, then the genus would be polyphyletic.
Monophyly 
 Since biologists by and large tend to prefer monophyletic groups, in this case, they would likely either split the genus or broaden it to include the additional forms.
Monophyly 
 Sometimes taxonomists are frustrated fitting plant species into a monophyletic group because of polyploidy.
Monophyly 
 There is clear evidence that some polyploid plant species are of multiple origins (the species has arisen more than once).
Monophyly 
 For example, Salsify, the hybrid goat's-beard, (Tragopogon miscellus) has formed as many as 20 times in eastern Washington.
Monophyly 
 Also, it can happen that hybrids between two close plant species undergo polyploidy, and the polyploids continue as a new and distinct species.
Monophyly 
 Situations like this are outside the normal rules of descent, and are dealt with by special decisions, guided by the International Commission of Botanical Nomenclature (ICBN).
Lepidoptera 
 Earlier butterflies must have been adapted to a habitat of cycads and conifers, something which had not previously been suspected.
Lepidoptera 
 The difference between Lepidopteran larvae and sawfly larvae is that Lepidopteran larvae have tiny hooks on their prolegs.
Diurnal 
 Scientists sometimes use the word crepuscular to describe nocturnal  animals that are not active when it is very dark at night; they are mostly active near dawn, dusk, and sometimes when the moon makes a lot of light.
Skipper (butterfly) 
 Skippers used to be classified in their own superfamily, Hesperioidea, because they have their antennae clubs hooked backward like a crochet while the other butterflies have club-like tips to their antennae.
Skipper (butterfly) 
 For example, some species in the genera Erynnis, Hesperia, and Amblyscirtes cannot currently be distinguished in the field even by experts.
Skipper (butterfly) 
 The only reliable method of telling them apart involving dissection and examination of the genitalia.
Energy conservation 
 This may result in an increase of financial capital, environmental value, national and personal security, and human comfort.
Energy conservation 
 Individuals and organizations that consume energy may conserve energy to reduce costs and promote economic, political and environmental sustainability.
Energy conservation 
 This reduces the rise in energy costs, and can reduce the need for new power plants, and energy imports.
Energy conservation 
 The reduced energy demand can provide more flexibility in choosing the methods of energy production.
Energy conservation 
 The U.S. is the largest consumer of energy, although at current levels of growth, China may become the leading energy consumer.
Energy conservation 
 The U.S. Department of Energy categorizes national energy use in four broad sectors: transportation, residential, commercial, and industrial.
Energy conservation 
 Energy usage in the transportation and residential sectors (about half of U.S. energy consumption) is largely controlled by individual domestic consumers.
Energy conservation 
 Of the energy used in this sector, about 65% is used by gasoline-powered vehicles, mostly personally owned.
Energy conservation 
 The oil supply crises of the 1970s spurred the creation, in 1975, of the federal Corporate Average Fuel Economy (CAFE) program, which required auto manufacturers to meet progressively higher fleet fuel economy targets.
Energy conservation 
 The next decade saw dramatic improvements in fuel economy, mostly the result of reductions in vehicle size and weight.
Energy conservation 
 These gains eroded somewhat after 1990 due to the growing popularity of sport utility vehicles, pickup trucks and minivans, which fall under the more lenient "light truck" CAFE standard.
Energy conservation 
 In addition to the CAFE program, the U.S. government has tried to encourage better vehicle efficiency through tax policy.
Energy conservation 
 A "gas-guzzler" tax has been assessed on manufacturers since 1978 for cars with exceptionally poor fuel economy.
Energy conservation 
 While this tax remains in effect, it currently generates very little revenue as overall fuel economy has improved.
Energy conservation 
 Many urban areas offer subsidized public transportation to reduce commuting traffic, and encourage carpooling by providing designated high-occupancy vehicle lanes and lower tolls for cars with multiple riders.
Energy conservation 
 A car or truck moving at 55 miles an hour can get about 15 percent better fuel economy than the same car going 65 mph.
Energy conservation 
 According to the U.S. Department of Energy (DOE), as a rule of thumb, each 5 mph you drive over 60 mph is similar to paying an additional $1.20 per gallon for gas (at $3.10 per gallon).
Energy conservation 
 The residential sector refers to all private residences, including single-family homes, apartments, manufactured homes and dormitories.
Energy conservation 
 Energy use in this sector varies significantly across the country, due to regional climate differences and different regulation.
Energy conservation 
 On average, about half of the energy used in the U.S. homes is expended on space conditioning (i.e. heating and cooling).
Energy conservation 
 The efficiency of furnaces and air conditioners has increased steadily since the energy crises of the 1970s.
Energy conservation 
 The 1987 National Appliance Energy Conservation Act authorized the Department of Energy to set minimum efficiency standards for space conditioning equipment and other appliances each year, based on what is "technologically feasible and economically justified".
Energy conservation 
 Despite technological improvements, many American lifestyle changes have put higher demands on heating and cooling resources.
Energy conservation 
 The average size of homes built in the United States has increased significantly, from 1500 ft² in 1970 to 2300 ft² in 2005.
Energy conservation 
 The single-person household has become more common, as has central air conditioning: 23% of households had central air conditioning in 1978, that figure rose to 55% by 2001.
Energy conservation 
 As a cheaper alternative to the purchase of a new furnace or air conditioner, most public utilities encourage smaller changes the consumer can make.
Energy conservation 
 Consumers have also been asked to adopt a wider indoor temperature range (e.g. 65 °F in the winter, 80 °F in the summer).
Energy conservation 
 In most residences no single appliance dominates, and any conservation efforts must be directed to numerous areas in order to achieve substantial energy savings.
Energy conservation 
 However, ground source heat pump systems are the more energy efficient, environmentally clean, and cost-effective space conditioning systems available (Environmental Protection Agency).
Energy conservation 
 Current best practices in building design and construction result in homes that are much more energy conserving than average new homes.
Energy conservation 
 See Passive house, Superinsulation, Self-sufficient homes, Zero energy building, Earthship, Straw-bale construction, MIT Design Advisor, Energy Conservation Code for Indian Commercial Buildings.
Energy conservation 
 Smart ways to construct homes such that minimal resources are used to cooling and heating the house in summer and winter respectively can significantly reduce energy costs!
Energy conservation 
 The commercial sector consists of retail stores, offices (business and government), restaurants, schools and other workplaces.
Energy conservation 
 Energy in this sector has the same basic end uses as the residential sector, in slightly different proportions.
Energy conservation 
 Space conditioning is again the single biggest consumption area, but it represents only about 30% of the energy use of commercial buildings.
Energy conservation 
 A number of case studies indicate that more efficient lighting and elimination of over-illumination can reduce lighting energy by approximately fifty percent in many commercial buildings.
Energy conservation 
 Commercial buildings can greatly increase energy efficiency by thoughtful design, with today's building stock being very poor examples of the potential of systematic (not expensive) energy efficient design (Steffy, 1997).
Energy conservation 
 Commercial buildings often have professional management, allowing centralized control and coordination of energy conservation efforts.
Energy conservation 
 Solar heat loading through standard window designs usually leads to high demand for air conditioning in summer months.
Energy conservation 
 An example of building design overcoming this excessive heat loading is the Dakin Building in Brisbane, California, where fenestration was designed to achieve an angle with respect to sun incidence to allow maximum reflection of solar heat; this design also assisted in reducing interior over-illumination to enhance worker efficiency and comfort.
Energy conservation 
 The industrial sector represents all production and processing of goods, including manufacturing, construction, farming, water management and mining.
Energy conservation 
 Increasing costs have forced energy-intensive industries to make substantial efficiency improvements in the past 30 years.
Energy conservation 
 For example, the energy used to produce steel and paper products has been cut 40% in that time frame, while petroleum/aluminum refining and cement production have reduced their usage by about 25%.
Energy conservation 
 These reductions are largely the result of recycling waste material and the use of cogeneration equipment for electricity and heating.
Energy conservation 
 The energy required for delivery and treatment of fresh water often constitutes a significant percentage of a region's electricity and natural gas usage (an estimated 20% of California's total energy use is water-related.)
Energy conservation 
 In light of this, some local governments have worked toward a more integrated approach to energy and water conservation efforts.
Energy conservation 
 Unlike the other sectors, total energy use in the industrial sector has declined in the last decade.
Energy conservation 
 While this is partly due to conservation efforts, it's also a reflection of the growing trend for U.S. companies to move manufacturing operations offshore.
Energy conservation 
 The usage of telecommuting by major corporations is a significant opportunity to conserve energy, as many Americans now work in service jobs that enable them to work from home instead of commuting to work each day.
Energy conservation 
 Lumina Technologies, Analysis of energy consumption in a San Francisco Bay Area research office complex, for (confidential) owner, Santa Rosa, Ca.
Cogeneration 
 Cogeneration (also combined heat and power, CHP) is the use of a heat engine or a power station to make both electricity and useful heat at the same time.
Cogeneration 
 Conventional power plants emit the heat created as a byproduct of electricity generation into the environment through cooling towers, as flue gas, or by other means.
Cogeneration 
 Combined heat and power captures the byproduct heat for domestic or industrial heating purposes, either very close to the plant, or - especially in Scandinavia and eastern Europe - for distribution through pipes to heat local housing.
Cogeneration 
 Byproduct heat at moderate temperatures (100 to 180°C) can also be used in absorption chillers for cooling.
Cogeneration 
 A plant producing electricity, heat and cold is sometimes called regeneration or more generally: polygene ration plant.
Cogeneration 
 In separate production of electricity some energy is lost as waste heat, but in cogeneration this energy performs useful work (see energy).
Cogeneration 
 Thermal power plants (including those that use fissile elements or burn coal, petroleum, or natural gas), and heat engines in general, do not convert all of their available energy into electricity.
Cogeneration 
 In most heat engines, a bit more than half is wasted as excess heat (see: Second law of thermodynamics).
Cogeneration 
 By capturing the excess heat, CHP uses heat that would be wasted in a conventional power plant, potentially reaching an efficiency of up to 70%, compared with at most 40% for the conventional plants.
Cogeneration 
 A CHP plant can either meet the need for heat (heat driven operation) or be run as a power plant with some use of its waste heat.
Cogeneration 
 This requires heavily insulated pipes, which are expensive and inefficient; whereas electricity can be transmitted along a comparatively simple wire, and over much longer distances for the same energy loss.
Cogeneration 
 A car motor becomes a CHP plant in winter, when the reject heat is useful for warming the interior of the vehicle.
Cogeneration 
 This example scores the point that deployment of CHP depends on heat uses in the neighbourhood of the heat engine.
Cogeneration 
 Cogeneration plants are commonly found in district heating systems of big towns, hospitals, prisons, oil refineries, paper mills, wastewater treatment plants, thermal enhanced oil recovery wells and industrial plants with large heating needs.
Cogeneration 
 High cogeneration performance by innovative steam turbine for biomass-fired CHP plant in Iisalmi, Finland  (URL accessed on 30 March 2006)
Dew point 
 Condensation of water vapor starts when the temperature of air is lowered to its dew point and beyond.
Dew point 
 The dew point, like other measures of humidity, can be found from measurement taken by a hygrometer.
Región Autónoma del Atlántico Sur 
 There is also a popular tourist place called Corn Island, which is about 45 km from the capital Bluefields
Compressor 
 Compressor (software), a video and audio compression and encoding application made for use with Final Cut
Gas compressor 
 A gas compressor is a mechanical device that increases the pressure of a gas by reducing its volume.
Gas compressor 
 Compressors are similar to pumps: both increase the pressure on a fluid and both can transport the fluid through a pipe.
Gas compressor 
 Centrifugal compressors use a vaned rotating disk or impeller in a shaped housing to force the gas to the rim of the impeller, increasing the velocity of the gas.
Gas compressor 
 They are primarily used for continuous, stationary service in industries such as oil refineries, chemical and petrochemical plants and natural gas processing plants.
Gas compressor 
 With multiple staging, they can achieve extremely high output pressures greater than 10,000 psi (69 MPa).
Gas compressor 
 Centrifugal compressors are used in small gas turbine engines or as the final compression stage of medium-sized gas turbines.
Gas compressor 
 Diagonal or mixed-flow compressors are similar to centrifugal compressors, but have a radial and axial velocity component at the exit from the rotor.
Gas compressor 
 Axial-flow compressors use a series of fan-like rotating rotor blades to progressively compress the gasflow.
Gas compressor 
 Stationary stator vanes, located downstream of each rotor, redirect the flow onto the next set of rotor blades.
Gas compressor 
 The area of the gas passage diminishes through the compressor to maintain a roughly constant axial Mach number.
Gas compressor 
 Axial-flow compressors are normally used in high flow applications, such as medium to large gas turbine engines.
Gas compressor 
 They can be either stationary or portable, can be single or multi-staged, and can be driven by electric motors or internal combustion engines.