Suchergebnisse

En el siglo XX y hasta el día de hoy el mundo utilizó como fuentes energéticas primarias (de manera prioritaria) los denominados combustibles fósiles, a saber, el petróleo, el carbón y el gas natural. Sin embargo, los efectos sobre el ambiente que han dado lugar al cambio climático han generado una tendencia cada vez más creciente a reemplazar estas energías por fuentes más limpias como la eólica, la solar o la geotérmica. Aún se plantean acciones más radicales como reducir el consumo de energía de forma drástica para evitar una catástrofe global de proporciones inimaginables. Este proceso se ha denominado "la transición energética", que sin lugar a dudas se viene desarrollando en mayor o menor medida en casi todos los países del así llamado "primer mundo". En este artículo se analiza la situación de la matriz energética colombiana y las políticas del país de cara a este proceso de transición hacia energías limpias. ; During the 20th century until today the world spend, as primary energetic resources (with priority), fossil fuels such as oil, coal and natural gas. However, the effects on the environment which led to climatic change, have been generated a growing tendency to replace such forms of energy with cleaner ones like wind, solar and geothermal energy. Yet many people plan radical actions which implies a drastic reduction of energy consumption, in order to avoid a massive global catastrophe. This process has been denominated "energetic transition" and it's developed almost in every part of the "first world" contries. This article analyzes the situation within theColombian energetic matrix and the country's policies to face this transition process towards clean energies.

In the last 50 years, very many new energetic compounds have been made as potential ingredients for explosive, propellant and pyrotechnic formulations. Of these compounds very few have come to be used in military munitions. To obtain a better understanding of why this has been the case and to help address the discrepancy, the NATO Insensitive Munitions Information Centre (NIMIC) held a workshop in June 1994 open to representatives from government and industry within NIMIC member nations, to study what it is that makes a new energetic material useable. Issues that were addressed included : -what is currently being used from the current understanding of detonics and molecular modelling in the targeting and preparation of new energetic materials ; -what use is made by the energetic materials designer of present capabilities to predict the performance and safety of new compounds and formulations ; -what do the users require of predictive resources and molecular modelling in order to target more potentially useful new energetic materials ; -what are the user's requirements for useful new energetic materials and can these be interpreted as quantitative properties of energetic molecules. This paper presents a short summary of those conclusions of this NIMIC workshop that are relevant in the field of the understanding and modelling of detonation at a molecular level.

Argues that as the demand for oil exceeds its supply & the oil & natural gas markets experience a major restructuring, the US should invest in Russian oil & gas development & export. Such an investment would balance growing European rivalry, stabilize access to resources for the People's Republic of China through a proposed pipeline from Russia through China & to the Pacific, & offer oil & gas supplies to Asia & the west coast of the US. The US needs to establish contracts with new suppliers, & it can reach several desirable geopolitical goals at the same time. Contracts with Latin American could stimulate economic development & diversify the US dependence on the Middle East. This could improve the US position in the war on terrorism as well as benefiting US long-term national interests. L. A. Hoffman

This research was supported by the Office of Naval Research grant N00014-16-1-2858: "PCoD+: Developing widely-applicable models of the population consequences of disturbance". VH and AMdR benefitted from funding from the European Research Council under the European Union's Seventh Framework rogramme (F /2007-2013) / ERC Grant Agreement No. 322814 awarded to AMdR. ; Understanding the full scope of human impact on wildlife populations requires a framework to assess the population‐level repercussions of nonlethal disturbance. The Population Consequences of Disturbance (PCoD) framework provides such an approach, by linking the effects of disturbance on the behavior and physiology of individuals to their population‐level consequences. Bio‐energetic models have been used as implementations of PCoD, as these integrate the behavioral and physiological state of an individual with the state of the environment, to mediate between disturbance and biological significant changes in vital rates (survival, growth, and reproduction). To assess which levels of disturbance lead to adverse effects on population growth rate requires a bio‐energetic model that covers the complete life cycle of the organism under study. In a density‐independent setting, the expected lifetime reproductive output of a single female can then be used to predict the level of disturbance that leads to population decline. Here, we present such a model for a medium‐sized cetacean, the long‐finned pilot whale (Globicephala melas). Disturbance is modeled as a yearly recurrent period of no resource feeding for the pilot whale female and her calf. Short periods of disturbance lead to the pre‐weaned death of the first one or more calves of the young female. Higher disturbance levels also affect survival of calves produced later in the life of the female, in addition to degrading female survival. The level of disturbance that leads to a negative population growth rate strongly depends on the available resources in the environment. This has important repercussion for the timing of disturbance if resource availability fluctuates seasonally. The model predicts that pilot whales can tolerate on average three times longer periods of disturbance in seasons of high resource availability, compared to disturbance happening when resources are low. Although our model is specifically parameterized for pilot whales, it provides useful insights into the general consequences of nonlethal disturbance. If appropriate data on life history and energetics are available, it can be used to provide management advice for specific species or populations. ; Publisher PDF ; Peer reviewed

Energie- und Ressourceneffizienz sind Qualitätsmerkmale, die auch für moderne Werkzeugmaschinen gelten. Der Energieverbrauch von Maschinen bis zu gesamten Fertigungsstandorten muss im Verhältnis zur erzielten Wertschöpfung deutlich gesenkt werden, um wettbewerbsfähig zu bleiben und unserer Verantwortung gegenüber der Umwelt zu entsprechen. Dieser Beitrag präsentiert anhand eines Fräsprozesses ein modellgestütztes Simulations- und Prognosesystem des Energieverbrauchs von kompletten Bearbeitungsoperationen auf einer Werkzeugmaschine als Basis energetischer Optimierungen.
 
Resource efficiency and energy consumption are critical quality attributes of modern machine tools. The energy consumption of machine tools, plants and facilities must be significantly reduced relative to the value added in order to stay competitive and fulfil our responsibility towards the environment. This article presents a model-based simulation and prediction system of the expected energy consumption of machine tools executing a given process NC-program as a basis for energetic optimization measures. It is exemplified by milling operations.

International correlations through the last years have been remarked as dramatic in character, and very often followed through with unpredictable events, such as the Arab spring, chronic and confessional wars raging through the Middle east, than the unprincipled informal collation of the great forces merging with variety and different in character formal and less formal state-of-actors, than worth mentioning is the recent war prelude in Ukraine which on top has all been spiced and made far more constrictive indeed by the arrival of the global economic crisis in energy resources as well as naturally found ones, that has well paid so far contributing led to the overflowing of the crisis itself from the world's center towards its margins. Since the end of the cold war, the most powerful and the most economically ascendant countries have started to promote a very new breed type of concept which deals with export and imposing of its own ideology. Diplomacy has well been turned into an instrument for realization of the external affair politics of the great powers and this diplomacy has been thus transformed from traditional in character to modern in origin, or better - public diplomacy. But this breed of public diplomacy had its own limits in terms of its range influence which was shortcut in the days of lack of energy resources as well as naturally found pack resources in the sense of energy excavation, and thus we witnessed the arrival of the newly formed type of diplomacy in place of the public diplomacy, named energetic diplomacy. Today energetic diplomacy is a representative of modern diplomacy or better a unique type of "stick and carrot" modulated for the weak and well developed rich states which are dependent on energy resources naturally found or not. During the era of the predomination of traditional politics over power in international correlations, it was then the most important thing who would be the one to deal with the most military power arsenal and later economic power as well that determined supreme leading force. Many of us would ask does this mean the reincarnation of the so called almost forgotten Cold War only now coming in such a shape that seems to be far more terrifying in character with a great deal of chance to impose the brink of a new world war and another humanitarian wash-out to humanity.

The alignment of the Greek national legislation with the corresponding EU legislation has enhanced the national efforts to pursue renewable Combined Heat and Power (CHP) projects. The scope of the present study has been the identification of the available biomass resources and the assessment of their potential. In this paper, we present the results from the administrative regions of Crete, Thessaly, and Peloponnese. The levels of lignocellulosic biomass in Greece are estimated to be 2,132,286 tonnes on an annual basis, values that are very close to the cases of other Mediterranean countries like Italy and Portugal. In respect to the total agricultural residues, Crete produces 1,959,124 tonnes/year and Thessaly produces 1,759,457 tonnes/year. The most significant streams are identified to be olive pits, olive pruning, and cotton ginning remnants, with more than 100,000 tonnes/year each. In the latter part of this manuscript, a case study is presented for the development of a CHP gasification facility in Messenia. The biomass energy potential of the area is very promising, with about 3,800,000 GJ/year. The proposed small-scale gasification technology is expected to utilize 7956 tonnes of biomass per year and to produce 6630 MWh of electricity and 8580 MWh of thermal energy.

Dissertação de mestrado em Engenharia de Redes e Serviços Telemáticos ; Wireless sensors networks consist of large numbers of small, battery-powered, self-organizing computing motes. Nowadays, these networks are considered ideal candidates for a wide range of applications such as environmental monitoring, military operations and other application fields where it is hard to maintain a continuous presence of human beings. Online remote reprogramming is usually carried out to update the code running on nodes due to factors such as changes in the environment or application. Remote reprogramming might be applied to the whole network or just to a subset of nodes (selective reprogramming), either way it is crucial to provide reliability for such procedure. Therefore, most of the approaches oriented to remote reprogramming resort to flooding the whole network, leading to a major waste of energy in network nodes. When dealing with selective reprogramming, the waste of energy increases steeply even when just a small number of nodes need to get the update messages. These messages may be received and retransmitted from all nodes in the network resulting in a waste of resources. This research identifies multiple scenarios for selective reprogramming and proposes a different energy-aware approach for each one trying to reduce energy consumption in the network by taking advantage of multiple and complementary solutions such as wise routing, clustering and the ability to manage nodes sleeping time instead of using the typical flooding approach. These approaches were tested and compared with typical flooding and Deluge solutions. The results show a significant reduction of the power consumption, thus, making the selective remote reprogramming more ...

The article describes conceptual questions of Ukraine's oil and gas energetics development. Characterized influenceof energetics on state economy, solve problems in social sphere and living standards. Analyzed world experiencein solve problems of energy security, including effective normative and legal regulation of relations betweenactors of economy in the energetic field. Investigated the natural-resources, technical and economical aspectsof ensure needs in natural gas of European Union countries, characterized potential treats associated with highmonopoly level of gas suppliers including JSC "Gasprom". Analyzed trends of the Europeans market of gas andfeatures to ensure its growing needs by expanding the resource base by increasing production of coal mine methaneand shale gas, diversifying sources and routes of gas supplying. Described basic problems of Ukraine gas supply atthe present stage and in the future, analyzed negative effects of monopoly dependence of Ukraine on natural gassupply from one source.Characterized perspective directions to diversify sources and routes of natural gas supply through using ofmodern technologies of transportation to meet the needs of national economy and enhance economic security. Onthe basis of the technical and economic calculations proved high economical effectiveness of using of new method ofmarine transportation of natural gas through pipelines which can move. ; Розглядаються концептуальні питання розвитку нафтогазової енергетики України. Охарактеризовановплив енергетики на стан економіки країни, на вирішення проблем соціальної сфери та рівень життялюдей. Проаналізовано світовий досвід вирішення питань енергетичної безпеки, у тому числі і за рахунокефективного нормативно-правового регулювання відносин суб'єктів господарювання в енергетичній сфері.Досліджено природно-ресурсні, технічні та економічні аспекти забезпечення потреб країн ЄвропейськогоСоюзу у природному газі, охарактеризовано потенційні загрози, пов'язані з високим рівнем монополізмуокремих постачальників газу, серед яких особливо виділяється ВАТ «Газпром». Проведено аналіз тенденційрозвитку європейського газового ринку та особливостей забезпечення його зростаючих потреб за рахунокрозширення ресурсної бази шляхом нарощування видобутку шахтного метану та сланцевого газу, диверсифікаціїджерел та маршрутів газопостачання. Охарактеризовано основні проблеми газозабезпечення Українина сучасному етапі та в перспективі, проаналізовано негативні наслідки монопольної залежності економікиУкраїни від постачання природного газу з єдиного джерела.Обґрунтовано перспективні напрямки диверсифікації джерел та маршрутів постачання природногогазу на основі використання сучасних технологій транспортування з метою забезпечення потреб національноїекономіки та посилення рівня енергетичної безпеки країни. На основі виконаних техніко-економічнихрозрахунків доведено високу економічну ефективність використання нового способу морського транспортуванняприродного газу за допомогою рухомих трубопроводів.

Розглядаються концептуальні питання розвитку нафтогазової енергетики України. Охарактеризовано вплив енергетики на стан економіки країни, на вирішення проблем соціальної сфери та рівень життя людей. Проаналізовано світовий досвід вирішення питань енергетичної безпеки, у тому числі і за рахунок ефективного нормативно-правового регулювання відносин суб'єктів господарювання в енергетичній сфері. Досліджено природно-ресурсні, технічні та економічні аспекти забезпечення потреб країн Європейського Союзу у природному газі, охарактеризовано потенційні загрози, пов'язані з високим рівнем монополізму окремих постачальників газу, серед яких особливо виділяється ВАТ «Газпром». Проведено аналіз тенденцій розвитку європейського газового ринку та особливостей забезпечення його зростаючих потреб за рахунок розширення ресурсної бази шляхом нарощування видобутку шахтного метану та сланцевого газу, диверси- фікації джерел та маршрутів газопостачання. Охарактеризовано основні проблеми газозабезпечення України на сучасному етапі та в перспективі, проаналізовано негативні наслідки монопольної залежності економіки України від постачання природного газу з єдиного джерела. Обґрунтовано перспективні напрямки диверсифікації джерел та маршрутів постачання природного газу на основі використання сучасних технологій транспортування з метою забезпечення потреб національної економіки та посилення рівня енергетичної безпеки країни. На основі виконаних техніко-економічних розрахунків доведено високу економічну ефективність використання нового способу морського транспортування природного газу за допомогою рухомих трубопроводів. ; The article describes conceptual questions of Ukraine's oil and gas energetics development. Characterized influence of energetics on state economy, solve problems in social sphere and living standards. Analyzed world experience in solve problems of energy security, including effective normative and legal regulation of relations between actors of economy in the energetic field. Investigated the natural-resources, technical and economical aspects of ensure needs in natural gas of European Union countries, characterized potential treats associated with high monopoly level of gas suppliers including JSC "Gasprom". Analyzed trends of the Europeans market of gas and features to ensure its growing needs by expanding the resource base by increasing production of coal mine methane and shale gas, diversifying sources and routes of gas supplying. Described basic problems of Ukraine gas supply at the present stage and in the future, analyzed negative effects of monopoly dependence of Ukraine on natural gas supply from one source. Characterized perspective directions to diversify sources and routes of natural gas supply through using of modern technologies of transportation to meet the needs of national economy and enhance economic security. On the basis of the technical and economic calculations proved high economical effectiveness of using of new method of marine transportation of natural gas through pipelines which can move.

Current tools and methods for assessing water supply systems no longer meet the new sustainability challenges, mainly the balance of the close relationship between water and energy in the perspective of unsustainable use of water resources and energy crisis. In this context, this study aimed to develop a model for hydro-energetic assessment of water supply systems, based on the systemic approach and diagnostic and simulation actions of the operation of water flows and electricity consumption. The analysis was developed in two steps, namely the development of the model and its formulations and subsequent application to the water supply system using synthetic data. The results showed that the developed model was effective in assessing the proposal, demonstrated easy practical applicability in any unit arrangement, promoted systemic understanding of water and electricity losses in the units in the stages of production, processing and distribution and in the system as a whole, and provided decision making for corrective actions with greater systemic impact. Finally, the proposed model represents an important technology in the search for improved social, economic and environmental sustainability of water supply systems

Using the example of various groups of herbivorous mammals, it is shown that the spatial, seasonal and long-term dynamics of energy resources directly affects the level of their consumption by animals, determines changes in the intensity of reproduction, mortality and migration processes, and, ultimately, the state and stability of populations. The supply of nutrients and energy is initially limited, that determines certain forms of ecological processes according to the hierarchy of components of the energy budget. The energy balance of the organism acts as a universal integral indicator of the effectiveness of the adaptation capabilities of the organism to environmental factors at every moment of its life cycle.

In this article is considered the problem of military and technical cooperation between Russia and Republic of Tajikistan. Tajikistan is rich with natural resources and hydro energetic resources. Cooperation in the sphere of defense gives possibility to protect itself from outside danger. Tajikistan's cooperation with Russia according 170 treaties and agreements which is valid till now are vividly shown in this article. ; In this article is considered the problem of military and technical cooperation between Russia and Republic of Tajikistan. Tajikistan is rich with natural resources and hydro energetic resources. Cooperation in the sphere of defense gives possibility to protect itself from outside danger. Tajikistan's cooperation with Russia according 170 treaties and agreements which is valid till now are vividly shown in this article.