bluuebunny/crossref_metadata_2025 huggingface dataset:
АЛЬТЕРНАТИВНЫЕ МЕТОДЫ ХОЗЯЙСТВОВАНИЯ СТОКАМИ НА ПРИМЕРЕ ПРИДОМОВОЙ ОЧИСТНОЙ СТАНЦИИ В СЛАВЕ
Authors: Малецки А.
Published: December 2016

Каждый человек вырабатывает определенное количество мусора в форме стоков. Существует проблема их уничтожения в большом объеме и отдельных домашних хозяйств. Неумножимые в основном запасы воды, а также связанные с этим все возрастающие расходы регуляции водных отношений делают необходимым их планировочное хозяйствование.
EKOLOĢISKĀS IZGLĪTĪBAS AKTUALITĀTE UN TĀS IESPĒJAMIE RISINĀJUMA CEĻI
Authors: Laizāne Ināra
Published: December 2016

Pašreiz, divdesmitā gadsimta nogalē, ar apkārtējo vidi saistītie jautājumi ir īpaši saasinājušies. Rakstnieks Jānis Baltvilks ir izteicies: “Galvenie draudu avoti Latvijas dabai ir divi. Viens ir nezināšana, ekoloģiskās izglītības trūkums, attīstīto zemju bēdīgās pieredzes neievērošana un nenovērtēšana. Un otrs nelaimju cēlonis ir cilvēka egoisms - tieksme par katru cenu sagrābt visus pasaulīgos labumus, nedomājot par rītdienu.”Iepriekšējo gadu pieredze rāda, ka par ekoloģisko zināšanu un pārliecību trūkumu mūsu valsts un sabiedrība ir dārgi maksājusi - gan morālā, gan materiālā ziņā [5]. Patreizējā laika posmā uz Zemes pastāv civilizācijas radītās globāla rakstura problēmas (l.zīm.).
FIZIKĀLU PROCESU SKAITLISKĀ MODELĒŠANA PLĀNOS SLĀŅOS
Authors: Kalis H. , Kangro I.
Published: December 2016

Apakšzemes slāņainās sistēmās fizikālie parametri vertikālā virzienā ir konstanti lielumi, kuru vērtības mainās plānos slāņos ar lēcieniem. Ņemot vērā sistēmas kārtaino struktūru, aprēķinot fizikālos lielumus (temperatūru, koncentrāciju slāņos), lieto dažāda tipa viduvēšanas [3] vai režģa metodes, izvēloties katrā slānī vismaz vienu režģa līniju [1,2]. Līdz ar to iespējams samazināt risināmās problēmas dimensitāti: paraboliskā vai eliptiskā tipa parciālā diferenciālvienādojuma vietā var risināt 1. un 2. kārtas parasto diferencālvienādojumu sistēmu. Šīs metodes ir taišņu metodes pamatā. Svarīgi ir pēc iespējas samazināt parasto diferenciālvienādojumu skaitu nepieciešamās precizitātes sasniegšanai.Viduvēšanas rezultātā katrā slānī rodas viens diferenciālvienādojums, bet režģa metodē, lietojot integrēšanu un interpolāciju vai galīgo tilpumu elementus, vismaz viens diferenciālvienādojums (1.veida robežnosacījumu gadījumā) vai 3 vienādojumi (3.veida robežnosacījumu gadījumā). Izrādās, ka ar režģa metodi var iegūt 2 diferenciālvienādojumu sistēmu, kuri jāintegrē pa dažādu vidu saskares līnijām, pie tam precizitāte ir augstāka nekā vienkāršai viduvēšanas metodei. Konstantu koeficientu gadījumā ir iespējams iegūt analītiskos atrisinājumus formulu veidā.
MODELLING OF SAPROPEL FLOW
Authors: Kaķītis Aivars
Published: December 2016

The most important problem for sapropel extraction by means of pumping systems is the reduction of energy costs for the transportation ofpure humidity sapropel in pipelines. The main parameters, which create energy losses in the flow, are: plastic viscosity pp and boundary shearing stress r0. The article presents results of mathematical modelling of pure sapropel flow. An equation is worked out which describes changes of shear stress in dependence of shear rate in the pure sapropel flow. The equation can be used for modelling different non-Newtonian plastic fluids with non? linear flow curves. The equation gives good accordance between theory and results of the experiment. Coefficient of determination reaches value R2-0.92-0.98The equation worked out for calculating of sapropel flow gives good accordance with experiment, R2=0.97. It can be used for calculating of non-Newtonian flows.
МАТЕМАТИЧЕСКОЕ МОДЕЛИРОВАНИЕ НОРМИРОВАНИЯ НОВЫХ ХИМИЧЕСКИХ СОЕДИНЕНИЙ В ОБЪЕКТАХ ОКРУЖАЮЩЕЙ СРЕДЫ
Authors: Яриновский Б. , Кангро И.
Published: December 2016

Стремительное развитие химии и энергетики, промышленного производства и расширение масштабов всех отраслей хозяйства, а также урбанизация с широким использованием предметов бытовой химии и автомобильного транспорта фактически приводят к прогрессивно нарастающему включению в биосферу свыше одного миллиона несвойственных природе химических веществ, а всего во всём мире известно более 4 миллионов химических веществ. Кроме того, получение каждого нового вещества связано с использованием не менее двух полупродуктов или сопутствующих продуктов.
DIRECT AND SUPPLEMENTARY SHADOWS IN THE TASK OF THE EFFICIENT DESCRIPTION OF CLASSES
Authors: Grekov Roman
Published: December 2016

One of the best techniques of feature efficiency estimation is based on the application of composition of the binary relations, i.e. direct shadows of fuzzy sets. Furthermore, the analysis of the binary relations yields a significant increase in the efficiency of the method operation, and also a detailed understanding of the processes occurring during the process of composition under various conditions.Since the composition of the binary relations is exploited to estimate the efficiency of attributes by means of direct shadows of fuzzy sets, a question appears: what volume of the information regarding the efficiency of attributes can supplementary shadows of fuzzy sets bear ? The use of supplementary shadows along with the analysis of direct shadows of fuzzy sets will presumably give a more complete representation about the efficiency of features of classes.The experiments performed on solving tasks by means of the composition of direct and supplementary shadows have shown that imder certain conditions supplementary shadows can give some auxiliary estimation of the attributes efficiency. It was then decided to continue some of experiments to reveal the valid behavior of supplementary shadows under various statements of the task and various samples, and also provided that the quantity of classes and the degree of their participation in space were changed.In this paper, an example is considered where three classes participate on a three-dimensional space of attributes. The convolution of composition realization results, degrees of reduction, is also proposed to estimate the attributes available.
Экотоксикологические проблемы биотехнологии
Authors: Гредин В. , Гредин Г. , Шестаков В.
Published: December 2016

Проблема защиты окружающей среды от загрязнения отходами предприятий пищевой промышленности в настоящее время разработана недостаточно. На некоторых предприятиях этой отрасли производства наблюдается загрязнение воздушной среды, промышленных сточных вод вредными и экологически опасных веществами [1]. В проведенных в конце 80-х и начале 90-х годов исследованиях отмечается, что в будущем многие экологические вопросы, а также получение дополнительного количества пищевых веществ, кормовых добавок и т.д., могут быть решены с помощью биотехнологии [2,4]. Цель наших комплексных экотоксикологических исследований заключалась в разработке, на примере клеевого производства фирмы "Вита" (г.Олайне, Латвия), проблемы предотвращения загрязнения воздушной среды на рабочем месте загрязняемой бензином при недостаточно тщательном соблюдении мер безопасности на стадии обработки сырья, а также в изучении возможности применении гриба ро1урогу$ squamosus-42 для утилизации растворенных в сточных водах органических веществ, образующихся на стадии обработки сырья предложенным нами взамен бензина, биопрепаратом протосубтилином ГЗХ [5]. Вместе с тем исходя из современных требований в области охраны труда и окружающей среды, с помощью экспериментов на различных видах животных, определялась степень токсичности и опасности полученных промежуточных и конечных продуктов, а также выяснялась возможность использования биомассы гриба ро1урогув squamo$m-42, выращенной на полученной в процессе нашей работы гидролизате, в качестве добавки в корм рыб согласно предложенной проф. Маликовой рецептуре.
Slēpto neironu loma tiešās izplatības tīklos
Authors: Grabusts Pēteris
Published: December 2016

Parādīta slēpto neironu loma tiešās izplatības mākslīgajos neironu tīklos. Slēpto neironu skaita izteiksme parasti tiek noteikta katrā atsevišķā gadījumā empīriski. Aprakstītas metodikas slēpto neironu skaita noteikšanai.
ТЕХНОЛОГИИ УТИЛИЗАЦИИ МИНЕРАЛЬНЫХ ОТХОДОВ ГОРНЫХ ПРЕДПРИЯТИЙ И СТЕКОЛЬНОГО БОЯ
Authors: Эстеркин-Бабков В.
Published: December 2016

В настоящее время существуют разработанные и частично реализованные технологии получения ряда строительных материалов стеклобоя (тарного, бутылочного, кинескопного и др.) и кварцосодержащих минеральных отходов (песков вскрышных пород, кирпичного боя шлаков тепловых электростанций, песчаников, кварцитов и др.).Сущность ряда технологий сводится к спеканию смеси дробленых до определенной крупности минеральных отходов; помещаемой в специальные жаростойкие формы и пропускаемой через туннельную муфельную печь.По таким технологиям возможно получение весьма качественных отделочных материалов с широким набором наперед заданных свойств.В МГГУ исследования возможности получения различных стеклокристаллических материалов с использованием различных стекольных отходов и минеральных отходов различного состава и происхождения ведутся уже около 10 лет. Результаты исследований были реализованы на промышленных установках - например, в Михайловском железорудном комбинате. При этом использовалось промышленное оборудование туннельной печи типа ЛСК - 1 конструкции Ленинского стекольного завода с нихромовым плоскими нагревателями накаливания, устанавлеваемыми в своде печи, нагрев которых осуществлялся с применением систем автоматики по заданному режиму. Режим выбирался, исходя из результатов исследований конкретных сырьевых материалов данного горного предприятия, где устанавливалось оборудование дня получения стеклокристаллических материалов.
USING OF WOOD INDUSTRY RESIDUES IN NATIONAL ECONOMY- NEW AND PERSPECTIVE BRANCH IN THE ENVIRONMENTAL MANAGEMENT
Authors: Blahins Jānis
Published: December 2016

Aim of report is to punctuate actuality and benefits can be given by correct management of wood residues at Latvia, in the economic, social, and environmental spheres. Main task is to inform . the public about some outstanding possibilities to utilize wide spectrum of wood residues with certainly positive economic gain, in opposition the state today though residues habitually are damaging the environment with no benefits at all. Especially are given knowledges about ramial chipped wood technology or Sylvasol, and use of wood gasification for asynchronous electro generation needs. Methods used includes studies of literature, analyze o f data available. For the superior effect on peoples lifestyle, economy, life and environment quality as equal of co-solving number of Global environmental problems, introducing the system of wood residues management in Latvia ought to be observed as ultimately profitable fieldfor further outbreaks in environmental sciences and management.
A STUDY OF DECISION TREE ALGORITHMS FOR CONTINUOUS ATTRIBUTES
Authors: Boļakova Ieva
Published: December 2016

Nowadays a lot of different algorithms for decision trees construction exist. With the help o f these algorithms one can make classification o f both discrete and continuous data. The aim o f this paper is to explore decision tree algorithms for continuous attributes. There are investigated CART (Breiman et al, 1984) and C4.5 (Quinlan, 1992) in this paper. The comparison of these methods was done in the process of exploration. As a result of the usage o f both algorithms, the conclusions about CART and C4.5 utilization advantages were drawn.
ENVIRONMENTAL PROTECTION DURING CONSTRUCTION OF MOTORWAYS
Authors: Chrzan Tadeusz
Published: December 2016

In this paper given and analysed are the factors related to the construction of motorways and having a negative impact on the environment. Given are the conditions o f the assessment of the impact of the motorways on the environment, arable land andforests and cultural heritage.
CONTENT OF EXTRACTIVE SUBSTANCES IN THE PINE WOOD UNDER VARIOUS GROWTH CONDITIONS
Authors: Cīrule Dace , Lavnikoviča Ilzīte , Alksne Anda , Hrols Jurijs
Published: December 2016

Studies of the chemical composition of Pinus sylvestris L. were performed. The studies embraced all the largest pine populations and the most spread forest types in Latvia. Samples for chemical analyses were taken in 4 stem heights, separately from sapwood and core. The obtained results indicate that the content of cellulose and lignin for trees from different regions and forest types in one stem localization differs moderately. The essential distinctions from the point of view of the chemical composition of pine wood suggests only the extractives content in wood. Common tendencies are observed for the distribution of extractives (EBE) throughout the stem for trees both different regions and forest types. In all stem heights EBE are more in core than in sapwood. To assess the effect of growth conditions on EBE content the results obtained for the same localization in the stem were compared. In all forest types and regions the EBE content in wood is higher as compared with the wood from less ecologically touched regions. In addition the substances extractable with hot water (WE) were determined. It is characteristic that both EBE and WE are less in pine trees grown in drained areas.
FORCED ANAEROBIC BIOCONVERSION
Authors: Dubrovskis Vilis
Published: December 2016

Forced bioconversion of solid organic wastes as technology for Latvia conditions is presented. Every inhabitant produces 200~300kg solid wastes, about 0,6 mind per year in Latvia. Different technologies are used for utilisation of these wastes. The most popular are: landfilling, sorting and recycling, incineration, composting and anaerobic digestion for organic wastes. As new technology? in Latvia is forced bioconversion of municipal solid organic wastes. Approximately 250000 tons solid wastes per year are coming to landfill Getlini. 24% from them are usable for anaerobic digestion. Regulating of temperature and moisture content in wastes gives possibility to optimise process of bioconversion. Forced anaerobic bioconversion proceeds 4 -7 times faster as normal bioconversion in landfill. For this technology is necessary less investment for incineraton anaerobic digestion in bioreactors and composting in tunnels or halls. It is preferable for smaller landfills in Latvia too. For big landfill, where has sorting, the best solution: approximately 30% recycling, 25% wet organic for forced bioconversion, 45% for incineration.
USED SMEAR OILS IN LATVIA
Authors: Freimanis Jānis , Stonkuss V.
Published: December 2016

Used motor oil reprocessing is offered also for Latvian conditions. The benefits from it consists in preventing of environment pollution by metal oxides and unknown toxic substances in flue gases, evolving from, or due to possible catalytic synthesis during the waste oil incineration, if the latter was disposed as before. The main such pollutants from Latvian waste oils are sulphur dioxide, Zn, P, Pb, Cr, Ni and Mo oxides, as well believed to be also heavy aromatic hydrocarbons. Besides, the reprocessing completely lifts up the subsoil water pollution danger in case o f waste oil occasional spillage.The used motor oil reprocessing by its recovery, vacuum distillation and marketing is proved to be economically profitable, if the world crude oil prices are not lower than 25 USD/bbl, and may serve as an additional resource for a local lube oil manufacturing for Latvia, as well as a way of diminishing of fresh lube oil imports.The main obstacles for the enterprise under consideration to be overcomed are believed to be the psychological inertia of oil users to dispose their wastes in a proper way and also the insufficient oil collection infrastructure in the country.
REED OVERGROWTH UTILISATION
Authors: Kronbergs Ēriks , Plūme Imants , Kaķītis Aivars
Published: December 2016

The rootfelt properties are investigated for development of technologies for Lake’s overgrowth removal and utilisation. The specific energy of disintegration of rootfelt vary from 7,3 to 18,1 kJ/m2 in dependence on methods used for overgrowth partition. The minimal density of rootfelt is 220 kg/m3 at a surface and the density increases to 1050 kg/m3 in deep layers o f overgrowth. The moisture content (dry basis) of rootfelt vary from 800 % to 250 % and organic matter content lower from 96 % to 25 % in dependence on depth and location of rootfelt in watercourse. The suitable methods and technologies are elaborated for rootfelt removal and biomass utilisation for litter, compost production or for production of Constructed Reedbeds for Effluent Treatment.
ECOLOGICAL ASSESSMENT OF THE POWER LINE WOOD POLES PRODUCTION PROCESS
Authors: Miklaševičs Ziedonis
Published: December 2016

For maintenance of the technological process, control and ecological assesment it is necessary to perform an estimate of environmental aspects that could have a sensible impact to environment. Environmental aspects and its impact is analyzed in the report. In the report is developed: 1. Friendly to environment technological scheme for production of wood poles for power lines. 2. Principial scheme and models o f hazard estimate 3. Hazard charts for the environmental defence 4. Algorithm of estimate of ecological for the environment That depends o f the problem’s topicality and enumeration of the hazard factors the specific problems solutions are offered that allow to controlthe manyfacturing process from the view of allowance need related to environmental defence.
PHYSICO-CHEMICAL FEATURES OF WATERS AND BIOCOENOSIS OF A MEROMICTIC RESERVOIR IN THE YEARS 1981-1998 IN THE LEKNICA REGION (WESTERN POLAND)
Authors: Najbar Bartlomiej
Published: December 2016

The research concerned the biggest, the deepest and the youngest (25 years old) acidotrophic reservoir located 4 km south-east from Lqknica. It was created as a result of brown-coal mining and opencast method. The present pyrite was the cause of significant acidifying and salinity of waters. 17 years of physico-chemical examinations of waters showed a progressive difference between mixo- and monimolimnion that is increase or decrease of such indicators as pH, redox potential, total iron, sulphate and others. First symptoms of ageing o f the reservoir were visible. Biological examinations showed pancity of plant and animal species living in this reservoir and a very slow development ofbiocoenosis. The research concerned the biggest, the deepest and the youngest (25 years old) acidotrophic reservoir located 4 km south-east from Lqknica. It was created as a result of brown-coal mining and opencast method. The present pyrite was the cause for significant acidifying and salinity of waters. 17 years of physico-chemical examinations of waters showed a progressive difference between mixo- and monimolimnion that is increase or decrease o f such indicators as pH, redox potential, total iron, sulphate and others. First symptoms of ageing o f the reservoir were visible. Biological examinations showed pancity of plant and animal species living in this reservoir and a very slow development of biocoenosis.
MONITORING AND ANALYSIS OF ROOM-AND-PILLAR MINING WITH CONTINUOUS MINER IN ESTONIAN OIL SHALE MINES
Authors: Nikitin Oleg
Published: December 2016

In this paper, the modeling, analysis and monitoring of a room-and-pillar mining technology in an Estonian underground mines is presented. Technology is based on continuous miner as the primary production machine. Many technical and economic parameters o f production, including loss of useful minerals, depend on a correct choice of the sizes for these elements. Without the account o f reological properties o f covered rocks, in particular the character of change o f their long strength, the account of the sizes of rooms and pillars on a certain determined term is impossible. For the modeling, the existing room- and-pillars determination method by IMS and with formulas by V. Undusk, Visual Basic for Application in Excel, Maplnfo, and Fast Lagrangian Analysis of Continua was used. Model allows determining the parameters of spontaneous collapse of the pillars and\ surface subsidence, optimized the working parameters for continuous mining. Proposed method suits for stability analysis, failure prognosis and monitoring.
IMPACT OF VARIOUS AGRO-CHEMICALS ON WINTER WHEAT GROWTH INTENSITY
Authors: Oboļeviča Daiga , Ruža Antons
Published: December 2016

Also, each treatment of the field results in a certain stress for the plants. The natural physiological processes within a plant are hindered influencing the growth of a plant. The objectives of the paper were to determine influence of retardant, herbicide and nitrogen on growth dynamics and the development o f vegetation stages in winter wheat. The field experiments were carried out during 1998 to 1999 in Research and Training Farm "Pēterlauki" on sod calcareous medium loam, pH k c l — 7.0, humus content 20 to 25 g kg 1 in soil. The research was carried out in the fields o f intensive type of winter wheat 'Otto' with the following treatments: control; control + herbicide; control + retardant; Ngo + 70 +40 + retardants. Herbicide Dialen (2,01 ha~’) and retardant Cikocel (1,5 l haT1 ) was applied during the final stage o f tillage, when testing parted nitrogen fertiliser, the first part (N go) was used after vegetation period was resumed. The second part (N70) was applied at the beginning of stalking stage (Zadoks Growth Stage 30). The third part (N40) - during shooting into ears. The grovAng dynamics was registered by aucsinographs (designed by I.Gronskis, M.Āboliņš). This equipment allows to observe and to register the intensity o f plant growth length within twenty-four hours. Registration tapes were changed every twenty-four hours. The analysis of the results showed that the most intensive plant growth happened in the morning (9:00 - 12:00 a.m.) and in the afternoon (3:00 - 6:00 p.m.). A decrease in the growing intensity was observed during night and midday. The data show how that the growth of winter wheat was seriously hindered even 2 weeks after the treatment with agro-chemicals. Winter wheat growing in length stops in the middle of flowering stage.
EVALUATION OF ENVIRONMENTAL QUALITY IN PANEVĖŽYS ACCORDING TO CONTAMINATION LEVEL OF DUG WELLS
Authors: Radzevičius A. , Zinkutė R.
Published: December 2016

Part of inhabitants of Panevezys, living in the city and near LiUdyne municipal waste landfill, still consumes water from dug wells. The aim was to investigate whether they are much polluted by toxic chemical elements and what is the main reason of their pollution. Geochemical monitoring data of dug wells in 3 industrial and 2 residential districts, as well as near LiUdyne municipal waste landfill were used. Water samples were analysed by AAS for V, Co, Ni, Cr, Cu, Pb, while sediment samples - by DC arc ES and XRF for total content of wider spectrum o f elements and by AAS for speciation o f the above mentioned 6 elements. Water quality was controlled in comparison with limit values of water for consuming, while the danger o f sediment pollution - according to recommended total contamination index levels for sediments and hygienic norms for mobile forms in soil. Sediments from dug wells can be effectively used as indirect inditator of their water pollution over longer period. Contamination from point sources in Panevezys is not the main reason of dug well pollution, the leading role belongs to local pollution in their sanitary zones. Therefore good care must be taken o f them.
ENERGOECONOMICS OF ELECTRICAL DRIVES FOR WASTE WATER AERATION UNITS
Authors: Šnīders Andris
Published: December 2016

This article discusses essential aspects of Induction motor’s (IM) selection for reconstruction projects of waste water purification plants as well eventual saving o f electric power in waste water pneumatic aeration units by using regurable electrical drives. Experience has proven that it is almost always cost effective to raplace old unefficient motor with new energy efficient and reliable unit. Anyway economical calculations must be perform. The paper considers methods and results o f economic effect calculation from energy savings in three phase IM dependent on their efficiency, power factor, operation time and reliability. The higher the motor’s energetic indices, the higher the effect from electrical energy saving and the lower the payment time of additional charges. Most electric power is consumed during waste water pneumatic aeration because it is an uninterrupted process. Analysis of the biological oxygen need for communal waste water purification prove that the medium required air blower’s productivity is 50- 60% of maximum value. Therefore the regulation of air blowers by using frequency converter is vitally important for energy saving and profitability o f communal waste water biological purification plants. Calculations show that use of reguable air blower with frequency converter is profitable for medium and large scale purification plants. The payment time of the additional charges for frequency converter and automation are about 2 years and lower if the rated power of air blower’s electrical drive is 15 kW and higher, but medium energy saving exceeds 30% in comparison with rated value.
АНАЛИЗ ОСНОВНЫХ ИСТОЧНИКОВ ОШИБОК В ЭКОЛОГИЧЕСКОМ МОДЕЛИРОВАНИИ
Authors: Ужга-Ребров Олег
Published: December 2016

The ecological systems are very difficult and multiform. There are many errors in the modelling such systems. Sensitivity analysis of errors for model's outputs is integral part o f modelling. In this paper short review of error creating in ecological modelling is given.
INFLUENCE OF ENVIRONMENTALLY FAVOURABLE BIOSTIMULATORS ON THE YIELD AND QUALITY OF FLAX
Authors: Stramkale V. , Kondratovičs U. , Vikmane M. , Miške I. , Lejasbuda I. , Merge D. , Švarca J. , Belousova R.
Published: December 2016

Institute of Inorganic Chemistry o f Riga Technical University Studies on the effect o f preplant treatment of seed material with micronutrients BZn and BCu plus phytohormone Germin on the yield and quality of flax straw and flax seeds were continued using flax cultivar ‘Laura’. The yield and quality of flax straw and flax seeds increased significantly, especially under unfavourable environmental conditions. Anatomical studies on flax stems showed that the best effect on flax fibre formation was by treatment of seed material with copper borate BCu plus pytohormone Germin which resulted in a nearly uninterrupted fibre cylinder in the flax stems. Key words: Micronutrients, flax, pfytohormone, fibres.
DEVELOPMENT OF WEB-BASED INFORMATION SYSTEM (DISTANCE EDUCATION INFORMATION SYSTEM)
Authors: Žilvinskis Imants
Published: December 2016

The paper describes Distance Education Information System. The aim o f the system is to provide effective information exchange between teachers and students and to store information about students progress marks. Based on theoretical knowledge and practical experience tasks for such an information system are described, as well as possible ways of implementation and the real product - Distance Education Information System.
Symbiotically Fixed Nitrogen in the Soils of Latvia: Possibilities and Problems
Authors: Adamovičs A. , Klāsens V.
Published: December 2016

For the first time in the states of the Baltic region the symbiotically fixed nitrogen has been quantified under field conditions according to total – N difference method using various legume – grass swards. Long – term field trials (1997 to 2002) were established on Stagnic Luvisol. Binary legume – grass swards were composed of Medicago varia, Galega orientalis, Trifolium repens, Alopecurus pratensis, Dactylis glomerata, Festuca pratensis, Festuca rubra, Lolium perenne, Poa pratensis and Phleum pratense. Legume and legume–grass swards were developed on similar P and K fertilizer backgrounds. Swards were cut three times during the growing season. It is concluded that fodder galega in soils developed symbiotic system with effective nodule bacteria and provided the productivity of swards 8.9 to 10.5 t ha –1 DM.Additional input of 90 kg N ha–1 resulted in changes in legume development and decreased agrophytocenosis productivity. In mixed agrophytocenosis a part of symbiotically fixed nitrogen was utilised by grasses. It was indicated by the increase of nitrogen content in the roots and above – ground parts of grasses in treatments receiving no fertilizer N. Fourfold cutting of swards also negatively influenced the activity of symbiotic system and in corresponding variants the yield and the amount of nitrogen in the aboverground parts of plants was minor in comparison with threefold cutting.
DISEASE RESISTANT VARIETY – A WAY OF THE ECOLOGICAL FLAX PROTECTION IN LITHUANIA
Authors: Bačelis K. , Gruzdevienė E.
Published: December 2016

Different methods to control flax diseases are admissible in the modern plant protection. It is advised to treat seeds and growing plants by fungicides to kill the pathogens of fungal diseases. Fertilisation by microelements and using of right means of agrotechnology (optimal sowing time, resistant varieties etc.) are preventing plants from physiological injures. However, one of the most effective means against diseases is development and growing of resistant varieties.Fibre flax breeding has been carried out in Lithuania since 1922 in Dotnuva Plant Breeding Station. Since 1965 this work is being done in Upyte Research Station.In this paper we analyse a fibre flax collection in Upyte Research Station and show that some varieties are resistant to most widespread flax fungal diseases.
FIBRE FLAX BREEDING FOR HIGH FIBRE QUALITY
Authors: Bačelis K. , Jankauskienė Z.
Published: December 2016

The objective of flax breeding at the Upyte Research Station of LIA is to develop new varieties with a high yielding capacity, satisfactory resistance to lodging and diseases, as well of adequate quality to meet the demands of the textile industry. Two high yielding varieties with a good fibre quality ‘Vega 2’ and № 1547-11-7 have been developed at the Upyte Research Station of LIA recently. In the present paper we have provided a description of the origin of those 2 varieties, main yielding characteristics and fibre quality parameters. The variety ‘Vega 2’ produced 20 % higher stem yield, 18.3 % higher seed and 47 % higher long fibre yield than the standard variety ‘Orshanskij 2’. Long fibre quality of the variety ‘Vega 2’ is good: fibre is firm, flexible, fine and meets the demands of the textile industry. Stem yield of the variety № 1547-11-7 was similar to that of ‘Orshanskij 2’ and ‘Belinka’. Seed yield was 0.13 t/ha higher than that of the variety ‘Orshanskij 2’ and equal to the seed yield of ‘Belinka’. Long fibre quality of № 1547-11-7 is good and also meets the demands of the textile industry. The variety ‘Vega 2’ has been registered in Lithuania since 1997, in Latvia since 2001. The seed samples of the variety № 1547-11-7 have been transferred to the Genebank.
GEOTECHNICAL PROCESSES AND SOIL-WATER MOVEMENT WITH TRANSPORT OF POLLUTANTS IN THE ESTONIAN OIL SHALE MINING AREA
Authors: Erg K. , Reinsalu E. , Valgma I.
Published: December 2016

One of the most important industries of Northeast Estonia is oil shale mining. Ground movements caused by mining reach the ground surface easily due to shallow location of workings. A new, artificial topography is formed on undermined areas, where the ground surface depressions are alternating with rising grounds. When the Quaternary cover contains loamy sediments, the surface water will accumulate in the depressions. The response of usable lands on undermined areas depends on the degree of changes in the relief and water regime. The accumulation of solid residues by oil shale mines and processing plants has resulted in numerous ash hills, which are polluting the environment. The streams are polluted by phenols, oil products and sulphates. The main source of water supply is groundwater in the oil shale basin. The hydrostratigraphic section is represented by three aquifers. Two (Quaternary and Ordovician) of these aquifers are affected by the human activity. Intensive water consumption has caused a fall in the water level in these aquifers. Due to oil shale production the concentration of Ca2+, Mg2+, SO4 2- and Cl- contained in the groundwater from the Ordovician deposits is noticeably higher than in the water with a natural background level. The natural water chemical regime is restored at the cessation of mining.
Generation of Woodgas and its Rational Use for Combined Power and Heat Production at Rural Enterprises
Authors: Gulbis V.
Published: December 2016

During the last few years combined production of electricity and heat based on biomass gasification technology and on gas utilization in gas-fired engines has been widely reconsidered. This method is more sustainable and environmentally friendly provision of energy in the future. Latvia is rich in forests and the wood processing industry is developing very fast, giving about 4.5 mill. m3 of woods residue per year. The use of wood residue does not follow the increase of wood production. In Latvia we have abundant biomass resources such as wood harvesting and wood processing residues, waste wood and sawdust. As a first attempt to introduce biomass gasification technology in Latvia some researchers at the faculty of engineering of LUA are developing an integral small scale combined heat and power (CHP) system based on a used Russian-made diesel-alternator set with electrical output 100 kWe. The diesel is converted to dual fuel gas engine, using producer gas as the main fuel and gas oil as pilot fuel. To get sufficiently clean (tar content ? 250 mg/m3) woodgas for using in IC engine a downdraft type of gasifier was chosen designed and constructed on the “IMBERT” gasifier principles. The test runs of the first experimental model showed that the engine does not develop expected power because of high resistance of gasifier and gas cleaning system does not work sufficiently enough. There was rather high level of tar content in woodgas because the temperature in the reduction zone was to low. Calculations were carried out and a new technological scheme of gasification system was worked out, introducing innovative ideas aimed on improving the working parameters. The experiments and calculations showed that such a type of CHP plant could be a technologically and economically interesting option for small sawmills and farms in rural areas.
SIMPLE METHODS OF ENGINEERING CALCULATION FOR SOLVING STATIONARY 2 –D HEAT TRANSFER PROBLEMS IN MULTILAYER MEDIA
Authors: Kalis H. , Kangro I.
Published: December 2016

There are well-known different numerical methods for solving the boundary value problems for partial differential equations. Some of them are: finite difference method (FDM), finite element method (FEM), boundary element methods (BEM), and others. In the given work two methods FDM and BEM for the mathematical model of stationary distribution of heat in the multilayer media are considered. These methods were used for the reduction of the two-dimensional heat transfer problem described by a partial differential equation to a boundary – value problem for a system of ordinary differential equations. (ODEs). Such a procedure allows obtaining simple engineering algorithms for solving heat transfer equation in mulyilayer domain. In the case of three layers the system of ODEs is possible for solving analytically.
Purification Performance of Biological Two-staged Plant Sewage Systems
Authors: Halicki W. , Szymańczyk A.
Published: December 2016

In the following article, results regarding purification performance of one of several biological two-staged sewage systems constructed in Poland are presented. The system selected was built for purification of sewage from an environmental center in Pszczew in West Poland. The performance evaluation refers to the elimination of nutrients as well as organic compounds. The results are furthermore compared to legal purification requirements for sewage systems in Poland. Since the purification achieved was so high, the purified sewage water can be used for irrigation purposes of the green area in the grounds of the environmental center all year long. By closing this circle, the ecological effects of the method used for sewage purification are much increased.
CONCENTRATIONS OF THE MAIN NUTRIENTS (N, P, K, B, ZN) IN FLAX SEED, STEMS AND CHAFF
Authors: Jankauskienė Z. , Endriukaitis A. , Gruzdevienė E.
Published: December 2016

During 1996-1998 experiments were carried out at the Lithuanian Institute of Agriculture’s Upyte Research Station to measure the contents of the main nutrients (N, P, K, B, Zn) accumulated in flax plants (seeds, stems and chaff) at harvesting on the following backgrounds: not fertilized, fertilized with P20 and N15P20K60; applied with ZnSO4 at the rates from 0,35 to 4,0 kg ha-1. It was determined that fibre flax seeds accumulated 3.30–4.06 % of N, 0.55–0.78 % of P, 0.69–1.15 % of K, 39.5–68.5 mg kg-1 of Zn, 10.00–27.00 mg kg-1 of B, the stems – 0.32–0.88 % of N, 0.04–0.15 % of P, 0.38–1.45 % of K, 5.0–18.0 mg kg-1 of Zn, 5.16–30.84 mg kg-1 of B, the chaff – 0.94–2.34 % of N, 0.20–0.38 % of P, 0.18– 1.40 % of K, 14.5–57.0 mg kg-1 of Zn, 8.55–38.19 mg kg-1 of B. The obtained data could be used for calculating the amount of main nutrients removed from the soil with flax yield as well as for fixing fertilizer rates more precisely.
Biomass Properties for Mechanization of Conditioning Processes
Authors: Kronbergs Ē. , Šmits M.
Published: December 2016

Substitution of fossil feedstock for energy and raw materials by biomass is important measure for GHG emission mitigation. Development of energy crop production and agricultural residue utilisation for energy are important goals of the rural policy. As chemical fertiliser production and usage corresponds to the consumption of oil fuel, biomass usage directly for energy production or as fertiliser are activities with equal importance. The main rural resources for biomass eco-technologies in Latvia are cereal straw residues, energy crops, emergent vegetation and peat from wetlands and sediments from lakes. Wide range of biomass properties cause necessity of appropriate mechanization equipment for biomass conditioning accordingly collection, conversion and usage technologies. The ecosystem approach means taking into account the interrelationships among land, air water and all living organisms including humans for mechanization equipment design of biomass technologies. Complex mechanisation of biomass technologies is based on implementation of ecosystem approach and investigation of properties of biomass in conditioning processes. For solid biofuel production densification properties of chopped stalk materials with different additives (peat, rapeseed cake) had been determined.
THE ASSESSMENT OF HEAVY METALS POLLUTION OF WATER BODIES AND SOIL IN THE ZONE OF ECOLOGICAL DISASTER (CITY KARABASH)
Authors: Morozov V. , Labuntsova L. , Ponomarev A. , Tatarinov V.
Published: December 2016

The report gives intermediate results of research carried out as the start of the INTAS Project “Strategy development for long term pollution control in regions of extreme environmental risk (ENVRISK)” The work on the project is a logical continuation of the research by project INCO-Copernicus TOXICAL (Contract No ICA2- CT2001-0016) [Ref. to preceding Conference] [14]. The major goal of the work is to elaborate a strategy and methods of pollution assessment and monitoring of Argazinskoye water storage basin, which is a reserve of drinking water supply for he city of Chelyabinsk in order to take steps for mitigating the health risk of the population of the region. The Russian project participants of the United Institute of Physics of the Earth, Russian Academy of Sciences, were presented with the following tasks. ? Grading and summing up the available data on the geological and tectonic structure and heavy metal pollution of the region; ? To substantiate field observation stations network and points of sampling of soil, biomass and surface water for laboratory analysis of heavy metal content; ? Rating stations of monitoring surface water pollution by neutron logging in relation to ecological conditions of the region; ? To obtain data on areal distribution of heavy metals pollution of soils, underground water and biomass; ? To elaborate a model of major pollutants spreading with surface runoff and hydrology system of the region on the basis of GIS technologies; ? To work out recommendations for local authorities to minimize health risk of the population. Currently a map of sampling has been made, sampling techniques have been elaborated in compliance with effective norms (GOST), samples processing and partial chemical analysis have been carried out. Some results of the research are given below.
MINING BLOCK STABILITY PREDICTION BY THE MONTE CARLO METHOD
Authors: Nikitin O.
Published: December 2016

This paper analyses the stability of the mining blocks by the Monte Carlo method in Estonian oil shale mines, where the room-and-pillar mining system is used. The pillars are arranged in a singular grid. The oil shale bed is embedded at the depth of 40-75 m. The processes in overburden rocks and pillars have caused the subsidence of the ground surface. Visual Basic for Application was used for the modeling. Through Monte Carlo simulation, room-and-pillar stable parameters can be calculated. Model allows determination of the probability of spontaneous collapse of the pillars and surface subsidence by the parameters of registered collapsed mining blocks. Proposed method suits as an express-method for stability analysis and failure prognosis. It is applicable in different geological conditions, where the room-and-pillar mining system is used.
Spread of Heracleum Sosnowsky Manden in Madona District (Latvia) and Its Control Possibilities
Authors: Oļukalns A.
Published: December 2016

Heracleum sosnowsky Manden was introduced into Latvia in 1950-1960. That infancy of cultivation happened in Madona district, Barkava parish where it was cultivated from 1965 and gradually infected about 10 300 ha area of district (85% form H.sosnowsky total area in Latvia). In late eighties and early of nineties its spread in Latvia had been going out of control. H.sosnowsky Manden quickly pollutes not only open areas but also those along water reservoirs, roadsides and forest. Basic methods which were used for control of H.sosnowsky in trials were cutting, chemicals (glyphosate, dicamba, MCPA, nicosulfuron), growing of green manure plants (Italian reygrass, oil radish, buckwheat) and soil mulch with polythene.
Technical, Economical and Ecological Estimation of Up-To-Date Combined Soil Tillage, Fertilising and Sowing Machines
Authors: Pinnis U. , Ruciņš Ā. , Vilde A. , Cēsnieks S.
Published: December 2016

Comparative studies have been carried out to estimate the possibilities, purposefulness and efficiency of combine soil tollage, fertilising and sowing machines and units for field crops used on peasant farms under the Baltic conditions. It is found out that most widely used machines and units are aggregates combining pre-sowing tillage of soil (combined cultivators, or revolving power harrow), mineral fertiliser application (pneumatic distributors) and grain sowing (pneumatic, or mechanical sowing machines). As to the agrotechnical terms, the ploughing-sowing aggregates may have limited application. The most suitable are tractor-mounted machines. For combined aggregates preference should be given to more powerful tractors having frontally mounted equipment as well. In contrast to single-operational machines, the use of combined aggregates removes the weather risk, improves the quality of work, raises their efficiency, reduces the consumption of energy and fuel (accordingly, the amount of harmful exhaust gases) and cuts the total costs by 10-18 %. For agrotechnical, energetic, economical and ecological considerations the up-to-date combined aggregates of soil tillage; fertiliser application and sowing are efficient and should be widely introduced on the farms of Latvia.
Application of Lignosilicon and Azobacterine for Biological Agriculture
Authors: Serģe I. , Biteniece G. , Teliševa G. , Ļebedeva G. , Lielpētere A.
Published: December 2016

Influence of Lignosilicon – plant growth and development activator, synthesized by IWC on the basis of wood chemical processing waste, and "Azotobakterin" bacterial products commercially produced by Bioefekts Ltd, on oats quality and harwest were tested in field conditions. Products were added to oat seeds into the box of seeding – machine before sowing. Three variants (each field of 1 ha) with different dosages of products applied were used: 10 and 40 kg/ha of lignosilicon and 400 g/ha of azotobacterin. It was shown that on the background of all products tested the harvest of oat increased significantly, vegetation time shortened, plant resistance to diseases increased, grain quality improved; most of all this indices changed positively on the background of lignosilicon (dosage of 40 kg/ha). The results obtained have demonstrated that lignosilicon and azotobacterin has good prospects for biological agriculture.
UNCERTAIN PROBABILITIES
Authors: Uzhga-Rebrov O.
Published: December 2016

The uncertainty of probabilistic evaluations results from the lack of sufficient information and/or knowledge underlying those random events. Uncertainty representation in the form of second order probability distribution or interval evaluations does not cause any objections from the theoretical point of view. On the other hand, what is worthy in the second order probabilities is that they allow one to model a real uncertainty of subjective probabilistic evaluations resulting from the lack of information and/or knowledge. Processing of uncertain information regarding probabilistic evaluations can help make a validated decision about the collection of additional information aimed to remove completely or to reduce the existing uncertainty.
AN EXERGY ANALYSIS FOR MINERAL CARBONATION
Authors: Zevenhoven R. , Kavaliauskaite I. , Denafas G.
Published: December 2016

Magnesium oxide-based minerals such as serpentine and olivine may be used for long-term storage of CO2, from combustion of fossil fuels or industrial processes such as steel works, in the form of magnesium carbonate. Large resources of suitable minerals appear to exist in Finland and at many other locations worldwide. The efficiency of the mineral carbonation process can be evaluated using exergy analysis, which will allow for comparing different mineral deposits that are characterised by different composition and quality. Other factors that play a role are the temperature and pressure, the presence of other gases besides CO2 and the degree of magnesium carbonation that is reached. Important for the analysis is the calculation of the standard chemical exergy of the chemical species involved.
Back Propagation and Transformation Methods in Artificial Intelligence Systems
Authors: Moskvin G.
Published: December 2016

Detailed description of methods of back propagation and back transformation also distributions for training of neural networks is given. A comparative estimation of a priority of methods of back transformation and back propagation for the decision of tasks of synthesis and training of neural networks, also for intelligent automatic measuring and AI systems for the first time is carried out.