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Forest resources are the most significant natural resources of the state of Latvia. According to the second stage data of Forest Resource Monitoring, in 2014, Latvia has 3575 thousand hectares of forest land, which accounts for approximately 55.3 percent of the total territory of Latvia, while the total wood stock is estimated at 668 million cubic meters. A considerable part of it can be used for energy production, thus practically providing most of the necessary heat energy, a large part of the amount of electric...

The broadleave tree species have always been in the focus of attention of forest managers and owners because of valuable wood. Moreover, the presence of broadleaves increases the forest biological diversity. There is only a limited selection of tree species in Latvia ? the Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) Karsten), silver birch (Betula pendula Roth), pubescent birch (Betula pubescens Ehrh.), black alder (Alnus glutinosa (L.) Gaertn.), less represented - common ash (Fraxinus excelsi...

Calculation of the mining support in tunnels and/or underground facilities can be based on application of contemporary numerical methods, but sometimes it can be performed with the classical methods too. These methods can be found to be used in order to choose variants and ways of supporting, but also in the moments that unpredictably appears during the construction of facility. Before installing a permanent mining support, these methods can help the projector at the selection of type of support and ways of tempor...

Appropriate protection of the environment, as well as of the most vulnerable environmental factor, water, is impossible without the achievement of a civilization's progress in all its aspects (economic, social, etc.). Also, the lack of adequate economic support may lead to the impossibility of carrying out actions to protect and conserve water resources. Activities from eastern part of the Jiu Valley, constituted as integrated parts of economic growth and development, invariably degrade, through the specificity of...

The study presents the comparative analysis between pressure and carbon dioxide charts obtained after measuring a series of fermentation processes. Doughs used for measurements were obtained from different quality/extraction flours, type 650 and whole wheat (1850). Gathered data was used to verify a mathematical model for determination of carbon dioxide production during the fermentation process, using pressure variation in a sealed container (reactor). For the testing it was used an experimental stand composed of...

The study presents the comparative analysis between pressure and carbon dioxide charts obtained after measuring a series of fermentation processes. Doughs used for measurements were obtained from different quality/extraction flours, type 650 and whole wheat (1850). Gathered data was used to verify a mathematical model for determination of carbon dioxide production during the fermentation process, using pressure variation in a sealed container (reactor). For the testing it was used an experimental stand composed of...

The paper presents an analysis of the behaviour of an air-water vapour compression heat pump at the variation of some of the decisional parameters as the state of the fluid at the compressor intake. Different refrigerants as CO2, NH3 and R600a, and different schematics are considered. The large use of rotary compressors in the industrial and domestic heat pump area has determined the investigation of the influence of the wet compression. The analysis is based on the exergy concept that enables to point out the loc...

Wood-based materials belong to the popular and widely used materials in the building industry. For example, these plates can be easily used to create often complicated details. Not all wood-based materials are suitable for the proposed environment. The effect of mistaking the choice of the right wood-based material and its application to an inappropriate environment can then result in the destruction of the details of the particular part of the structure and thus often involves a considerable financial cost to rep...

Deformation analysis represents an actual and important theme, therefore methods for improving the tracking and analysis process of deformations, both for constructions and for lands, as well as diminishing the necessary time for deformation analysis, are the main concerns for the specialists and not only. When it comes to major constructions or constructions of particular importance, deformation analysis proves to be an extremely important tool. The results of the analysis can be used in decision-making systems f...

The research investigates the relation between the magnetic field deviations and the forest stand volume. The object of the experiment for the study of wood stock and related quantities was selected on the basis of the magnetic field deviations map. The Ogre Magnetic Field Anomaly Region has been selected for the research. The magnetic anomalies (magnetic field deviations) data were created digitally: a full polygon layer with values, vectorial data were obtained by adding the measurement data of the magnetic fiel...

Renewable-energy sources are considered to be the energy that is collected from sources that may be regenerated in a lifetime. The renewable-energy sources branch out in five types: wind power, hydropower, solar energy, geothermal energy and bio energy. However, in this paper, we are analyzing the water, solar and wind, since those three are the most exploited in Romania. Wind power refers to produce electric power, by mechanical powered generators when air flows through wind turbines. Alternatively, to fossil fue...

The wind energy is a modern and efficient solution that uses the air flow through wind turbines to mechanically power generators for electric power production, being an alternative to burning fossil fuels. Wind power is renewable, widely distributed, produces no greenhouse gas emissions, consumes no water and uses small land areas. A wind turbine converts the kinetic energy of the wind into electrical energy. The electrical power generator and the steel upper structure of a wind turbine are equipments where were i...

The aquatic systems of Kerch peninsula are unique groundwater manifestations situated on the area with a low technogenic pressure. Thereby these are very interesting object for the study of processes of the migration and accumulation of the geochemical markers (polycyclic aromatic hydrocarbons, PAHs) as the background areas. The study is devoted to the assessment of the processes on the geochemical barriers (GCB) ? self-organizing components of geochemical systems, where the activation of physical and chemical pro...

This study examined the spatial relations of the selected metals in stream sediments tributary of the Oltet River in longitudinal profile, along the entire length (185 km) in relation to geology, lithology and anthropogenic activities. Differences in regional geology from the northern to the southern of the Oltet River Basin are reflected in stream sediment geochemistry. The Olte? River crossing crystalline formations belonging to the Danubian Domain represented by metamorphic rocks (schist, gneisses, mica-schiste...

There have occurred significant changes in the world political stage over the last more than 20 years. Events of the recent decades have changed territory, economic, social, natural resource and environmental situation in Russia. Nowadays up to 70% of territory of the Russian Federation, nearly half of northern land areas of the globe are regarded as territory of the nordic region and the Arctic region. The notion ?Arctic region? (?Arctic zone?) has no distinct definition, it is frequently equated with the notion ...

Throughout the last few years, there has been a global trend to preserve protected green areas. Each nation is responsible for ensuring that such areas are not potentially destroyed by faulty social management and development. Therefore, a sustainable future can only be built with sufficient care for green infrastructure, which once destroyed is almost impossible to restore. Communities should thus actively participate towards protecting their local biodiversity and natural habitats, thereby improving their collec...

In the current forest typology?s scheme of Latvia the descriptions of vegetation are based on corresponding forest type?s ground vegetation in maturity stand. However, in practical forest management it is important to know forest ground vegetation?s development through all foresty cycle and valuate phytocoenoses state in every stand?s age and development?s stage. There are significant changes in ground vegetation?s taxonomic structure, projective covering and vertical structure in all forest types from clearing ti...

One of the most common geotechnical risk induced by earthquakes is liquefaction phenomena, which it has been responsible for building damages that directly influenced population and economy. The growing recognition of importance of geotechnical site conditions in earthquake-prone areas has been generated by concern about liquefaction observed in strong seismic motions that occurred during 20th century. The paper aims to substantiate the necessity of a rational assessment of uncertainties and risks related to seism...

The stoichiometry of metal?protein complexes is pH dependent. Since mass spectrometric measurements at higher pH values are difficult in the presence of usual buffers, we extended this approach to pH in excess of 10 by adding ethanolamine to the electrospray solution being investigated. Therefore, a new method for probing the metal ion-peptide complexes at high pH utilizing electrospray ionization mass spectrometry (ESI-MS) has been advanced. Nevertheless, the high pH ESI-MS spectra of peptides are far too complex...

The stoichiometry of metal?protein complexes is pH dependent. Since mass spectrometric measurements at higher pH values are difficult in the presence of usual buffers, we extended this approach to pH in excess of 10 by adding ethanolamine to the electrospray solution being investigated. Therefore, a new method for probing the metal ion-peptide complexes at high pH utilizing electrospray ionization mass spectrometry (ESI-MS) has been advanced. Nevertheless, the high pH ESI-MS spectra of peptides are far too complex...

The industrial activity of the last century has led to the severe environment pollution, especially in the areas where mining and smelting processes were involved. The impact of atmospheric emissions from the metallurgical plants was detected at great distances from the emission source. The main units for the processing of non-ferrous ores (in Romania) were located in Baia Mare (Maramures county ? MM), Copsa Mica (Sibiu county ? SB) and Zlatna (Alba county ? AB). In the Alba and Maramures counties there was and st...

City spatial development is strongly connected with the transport systems development. One of the spatial structure model type could determine implementation of the ecofriendly transport, whilst the other could affect against of the sustainable transport system. We consider three spatial development of the city models: linear city, radiant city and grid city. The article presents analysis of each city models, taking into account the implementation of the ecofriendly transport system modes and impact on the transpo...

In the article, the authors provide the analysis of the industry state in the field of software and hardware development on the FPGA basis. The primary emphasis is on high-level synthesis (HLS) tools, which allows making a custom design by a non-RTL engineer. The key factors limiting the extensive introduction of HLS in the industry are determined: in most cases is not allowing to get a good solution without an understanding of target microarchitecture and synthesis method; too complicated and unpredictable tool b...

The Paper present confined groundwater flow and solute transport modeling in water catchments area and wastewater system Giarmata, using the hydraulically modelling whit mathematical simulation. Modeling purpose is to constitute extending pollution propagation of aquifers generated of possible wastewater pumping station pollution. Pollution zone definition is necessary to settle technical measures to using drinking water systems. The used software for numerical modelling in this paper is Processing Modflow for Win...

In Latvia, English oak Quercus robur L. planting material is grown both as bare-root seedlings and bare-root plants. Its breeding is difficult, because the quality of planting material is affected by both abiotic and biotic factors. Damage caused by various factors may be spread evenly and unevenly in the area of cultivating planting material. The most common damage to seedlings and plants can be observed already in the spring, when new leaves begin to flourish and new shoots develop. It is clear that differences ...

The former village Rosiuta, now neighborhood of Motru city, located in Motru mining basin, is surrounded by sterile waste dumps and lignite storage platforms. These are a constant source of particulate matter which is carried by the wind over the inhabited area and affects the quality of breathing air. In order to evaluate the powders dispersion from these sources, it was made chemical and granulometric analysis of the particulate matter on several material samples collected from the area. Based on various meteoro...

This paper is about how to build a cheap modern temperature control system on an existing manufacturing system. The authors designed and implemented the control system to a tunnel type furnace for burning bricks used in constructions at SICERAM S.A. Company, Sighisoara, Romania. The bricks manufacturing phases are described in order to help the reader to understand the process complexity and the graph of the entire loading/unloading process is shown together with the tunnel furnace schematics. Then, the graphical ...

Maintaining health and physical condition of astronauts during long-duration space missions requires measures to prevent microgravity effects. At present, such measures consist in practicing certain physical exercises, in using elastic suites, as well as in special medication. However, the efficiency of these solutions is limited. An alternative approach, technologically more difficult, but considerably more efficient, consists in producing a state of artificial gravity in the module inhabited by the crew. Such a ...

Multifunctional motor vehicles are equipped with one or more working mechanisms actuated by hydrostatic drive systems, which consume most of the power installed on such vehicles in which the primary mechanical energy is generated by an internal combustion engine, usually Diesel engine. Given the large number of daily running hours, (of multifunctional motor vehicles) the energy consumed by working mechanisms becomes important, the same goes for the expenses, and therefore it is required to be used with maximum eff...

Nowadays, after periods of time without precipitation, more and more frequent rains are coming in with very high flows in very short time. In case of extreme precipitation phenomena, sewer networks can no longer take rainwater flows, which often occur with large damages, often with loss of life. Drinking water is not renewable. That is why it is important to protect drinking water sources by using rainwater more efficiently. By recovering, storing and using rainwater, costs are reduced by treating and transporting...

Drilling fluid significantly affects all technological operations in the process of deposit drilling and completion. The main task done by the drilling fluid is providing proper drilling and cleaning of the hole bottom from cuttings as well equilibration of the rock mass pressure, cooling and cleaning the drill bits. Moreover the drilling fluid should minimize the damage to the permeability of productive deposits in the near-well zone and maintain stability of the wellbore walls. For providing the correct protecti...

Winter pumpkin represents a seasonal crop of health and food interest due to its nutritional composition. The aim of the present study was to comparatively evaluate the content of the main antioxidant compounds, carotenoids and phenolics, from pumpkin (Cucurbita maxima) pulp as related to different pretreatment conditions. Samples of pumpkin pulp were subjected to three pre-extraction methods, as follow: freeze-drying, oven-drying at 60oC and freezing at -70oC. Conventional extraction of carotenoids and polyphenol...

Winter pumpkin represents a seasonal crop of health and food interest due to its nutritional composition. The aim of the present study was to comparatively evaluate the content of the main antioxidant compounds, carotenoids and phenolics, from pumpkin (Cucurbita maxima) pulp as related to different pretreatment conditions. Samples of pumpkin pulp were subjected to three pre-extraction methods, as follow: freeze-drying, oven-drying at 60oC and freezing at -70oC. Conventional extraction of carotenoids and polyphenol...

The use of various ingredients in the formulation of yogurt, in order to diversify a dairy product particularly appreciated by consumers, is a constant concern for industry specialists. The paper proposes the use pumpkin seeds in the recipe of a classic yogurt, in order to improve its physico-chemical, textural and sensory characteristics. Pumpkin seeds, like other oilseeds, are in the attention of specialists because they are a very good source of proteins and dietary fibers. For the consumer, the increase in the...

The use of various ingredients in the formulation of yogurt, in order to diversify a dairy product particularly appreciated by consumers, is a constant concern for industry specialists. The paper proposes the use pumpkin seeds in the recipe of a classic yogurt, in order to improve its physico-chemical, textural and sensory characteristics. Pumpkin seeds, like other oilseeds, are in the attention of specialists because they are a very good source of proteins and dietary fibers. For the consumer, the increase in the...

Designing flat roofs has many issues and decisions. This can be, for example, the decision on how to close the flat roof. By default, roofs are terminated at the periphery by means of attics or by creating a so-called rigid edge of the roof. This paper focuses on the first option, and therefore the termination of the flat roof using the atics. The author is dealing with the findings with regard to the way the proposal is implemented and the subsequent realization of the details. As a major waterproofing layer, fil...

Romania has an important rail network, of public use, consisting of about 10764 km of railway, some of which are affected by instability phenomena. Although the percentage of areas affected by instability in the entire network is insignificant, railway sections have some peculiarities, any difference in the order of the centrimetres appearing at the upper level of the rail can lead to the closing of the line, with important financial consequnce. The surface, affected by the instability phenomen was about 4,000m2, ...

World is changing rapidly. We are facing new reality and challenges. New global and complex solutions are needed to adapt to future reality. Tasks about landscape are coming to the forward more and more. It is necessary to speak about role of landscape in our life. Many points of view need to take into account when we want to speak about landscape and changes which are waiting for us in next decades. Question for researchers is how to obtain the best data for the best suggestions and recommendations for policy mak...

Economic activities in Jiu Valley, as integrated components of major geographical entities, are constantly degrading the area?s natural heritage by depositing large quantities of waste products resulted from coal extraction and preparation, abandoned buildings and poorly refurbished sites. In this respect, the current paper addresses these areas by identifying and classifying the potentially contaminated/contaminating industrial sites in Eastern Jiu Valley, depending on the type of activity carried out on site. Th...

The first results of using adaptive regression modeling (ARM-approach) in description of the latitude periodic change are analyzed. A multicomponent (polyharmonic) model of the latitude part observed dynamics containing between 14 and 21 harmonics requires interpretation and autoregressive forecasting of the 6th order providing high accuracy for the period of two years. This article provides the analysis, modeling, and forecasting of the latitude periodic change using the ?Automated System for Robust Modeling? (AS...

Murmansk region is a most dynamically developing region of the Arctic Zone of the Russian Federation, which combines many conflicts in the types of nature use by various maritime sectors, with a negative impact on fragile Arctic ecosystems. The existing Russian and international experience in the application of the concept of marine spatial planning (MSP) was analyzed in terms of its application for the Russian Arctic and the current state and prospects of the socio-economic development of maritime complex was stu...

To live in Global Information Society we should constantly increase our knowledge. The wish to possess core competences is a main reason of lifelong education. Due to Open Society and development of ICT teaching methods are changing. Education 3.0 based on the idea of connectivism involves collaborative learning. The article describes the experience of integration Massive Open Online Course into the process of formal education within the framework of students' self-work. The authors analyze results of an experimen...

Methane and carbon dioxide are among the most active of greenhouse gases that contribute to climate change. Anthropogenic sources have a significant share of their emission into the atmosphere. One of the major sources of emissions of these gases can be exploration activity and operating oil&gas industry. It is associated with the possibility of uncontrolled migration of reservoir gases in the course of work consisting of geological exploration and recognition of hydrocarbon deposits by drilling. In connection wit...

Lately, high penetration of intermittent renewable energy sources into power systems requires, besides efficient technologies employment, developing adequate control strategies to improve their performance. Given that their operation flexibility is constrained by short timeframe of foresight, energy storage systems represent an attractive solution that can mitigate the natural variability of renewable power plants electricity output, providing therefore enhanced quality of supply. The nonlinearity and uncertainty ...

The article deals with the modeling of the structure of the e-learning website with the possibility of changing the user interface in accordance with the information needs of users. The most popular content management systems (CMS) and learning management systems (LMS) have many necessary features, including using an uncluttered modern editable interface and configurable LMS front page of the e-learning course. But, as a rule, these systems do not contain the component that would be responsible for the ability to ...

Methods of deductive inference that are various modifications of the principle of resolutions are quite effective in logic. The results and justifications for the fuzzy conclusion of the resolution type are widespread in the predicate calculus. The existing models of the resolution inference are effective, and also quite simple and convenient, for conventional reasoning under incomplete information and for automatic processing of uncertain knowledge in interactive systems. However, in such models the set of genera...

The integration of a building into the environment can be achieved both from the architectural point of view and from the point of view of the used building materials, thus remarking material used since ancient times, namely wood. Wood is an organic, sustainable, environmentally friendly material that can reduce carbon dioxide emissions Due to the latest environmental protection requirements, economic issues related to construction costs and architectural diversity, it has been necessary to develop technologies re...

An important problem of modern civilization is the aging of societies. The effect of this phenomenon is and will be limited access of enterprises to young and middle-aged employees. This problem also applies to coal mine. First and foremost, young and middle-aged employees work in them. Therefore it will be necessary to undertake actions aimed at stopping already working workers and employing older people in the case of shortages. Extending the employment time in mining enterprises requires a proper approach to th...

Experience has shown that all buildings and constructions are subject to displacements and deformations. There are no absolutely stationary and non-deformable constructions. Deformations are also caused by variable loads acting on the construction. For example, loads caused by wind, solar radiation, vibrations from machines during operation, seismic stress and others. The area in which the tallest building in Romania, i.e. the 351.5 m smoke chimney in Baia-Mare, is located has a very low seismic activity. In these...

The necessity of fulfilling as many conditions as possible in the specification resulted in the creation of composite materials. This idea developed in the aerospace industry was later used successfully in all industrial branches. The two materials that have been used are chemically distinct, each of which retains its properties in the composite, but provides the assembly with different properties and characteristics. Thus, for the continuous phase, the matrix was used an aluminum alloy, and for the discontinuous ...