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To take capillary effect into account, a series of primary drainage experiments of water by a sample oil fluid have been studied. The experiments performed under different low flow rates on a horizontal high pressure glass type micromodel as a model of porous media. Based on conventional macroscopic flow equations,the relative permeabilities and capillary pressure are determined by parameter estimation technique from history matching of saturation and pressure data of unsteady state immiscible displacements. The Coery type of relative permeability and capillary pressure functions are used. The results show that the end point relative permeability of oil phase and the dynamic term of capillary pressure function increase with flow rate, but the saturation exponent of relative permeability functions are decreasing with flow rate. Also the results show that the capillary pressure and relative permeability curves are rate dependent and the relative permeability curves are increasing with flow rate. Key Words: Rate Dependent,Relative Permeability,Capillary Pressure,Unsteady State, History Matching,Micromodel

This study focuses on the mapping of oxygen-related defects in industrial monocrystalline silicon wafers. All mappings were obtained solely from resistivity measurements and specific furnace anneals. An emphasis is given on the boron-oxygen complex responsible for the light-induced degradation (LID) of the carrier lifetime in boron-doped wafers. It is shown that the predicted values for the lifetime limited by the boron-oxygen complexes after complete degradation are in very good agreement with the experimental observations. It is also shown that the present technique is a valuable tool to predict the cell LID from measurements on as-received wafers, which is of paramount interest for wafer/cell manufacturers. 28th European Photovoltaic Solar Energy Conference and Exhibition; 902-906

A new and applicable environmental rating tool for use as a policy tool, called EcoScore, was developed and allows evaluating the environmental impact of road vehicles with different drive trains or using different fuels. A single environmental indicator integrates different aspects of the environmental impact of the vehicles such as global warming, air quality depletion and noise pollution. To integrate these different aspects, the Ecoscore methodology includes different damage categories like: global warming, human health impairing effects and harmful effects on ecosystems. The contribution of the different normalised damages to the single value, called Ecoscore, is based upon a weighting system. The methodology can also be used for the ranking of heavy duty vehicles and two-wheelers. However, in this paper, the methodology will be explained using passenger vehicles and light-duty vehicles as an illustration. The methodology will be implemented by the Flemish government as a policy tool for the promotion of cleaner vehicles. An extensive database including vehicle records and their related emission data was used to develop, to validate and to analyse the environmental rating system. A sensitivity analysis was carried out which allowed the evaluation of the robustness of the methodology.

Valence band offset and valence band bending at the p+ hydrogenated amorphous silicon/n-type crystalline silicon (a-Si:H(p+)/n_c-Si) interface in heterojunction silicon solar cells (HIT) induce a p+ inversion layer which pushes the pn junction 20-25 nm deep in the c-Si side. The heavily hole populated interfacial inversion layer acts as the HIT cell emitter while the ultrathin amorphous silicon layer is the front contact. The impact of doping level and dangling bond defects in the a-Si:H layer and of interface states on the inversion layer properties is investigated by means of AFORS-HET simulations. Apart from the electric field created by the conduction band offset, the HIT cell performs like a c-Si solar cell which has an inversion layer emitter matching that of the HIT cell, with an open circuit voltage of 733 mV. The latter rolls off at relatively large interface (front surface) recombination velocity. Increasing the a-Si:H(p+) doping level modifies the peak hole concentration in the inversion layer and increases the front surface field. On the other hand, c-Si cell with an ultrathin dopant diffused emitter having also the same emitter hole profile sees its performance degraded at relatively low surface reombination because it suffers from bandgap narrowing and from doping dependent mobility degradation and has no front surface field. Inserting an ultrathin intrinsic or lowly doped a-Si:H spacer between a-Si:H(p+) and c-Si provides less hole population in the inversion layer which reduces Auger recombination and improves the open circuit voltage at low surface recombination to 735 mV despite the less effective front surface field. 28th European Photovoltaic Solar Energy Conference and Exhibition; 822-826

The relevance of this study is to solve the basic task for society to ensure sustainable management by improving the spatial management system of natural resource assets, increase their usage efficiency and ensure sustainable socio-economic development of Ukraine on this basis. At all levels of the state government, there appeared a need to ensure spatial management and transform the organizational structure of natural resource management on the basis of the introduction of a modern system of territorial natural entities with the change of relevant functions, mechanisms and powers in the direction of increasing the ecological and economic effect in various spheres of economic activity. Aim of the research: identification of the highest priority, to ensure sustainable management in resource constraints, the composition of threats and risks and their grouping; development of a closed scheme of permanent clarification of the most important, for spatial sustainable development, threats and risks. The methodological basis of the study is the work of domestic and foreign scientists on spatial management of natural resources, sustainable spatial development and economic security, regulations, analytical and statistical materials of ministries and departments, international organizations, other scientific and information materials. The study involves the use of a number of interrelated methods, including methods: analysis and synthesis; system analysis; economic and mathematical; expert assessments; graphic, etc. The scheme of grouping of organizational and economic mechanisms of realization of spatial model of management of sustainable management within a certain state formation is constructed. According to which a universal, for three stages of implementation of the corresponding type of macro- model (initiation, consolidation, incorporation) spatial management of sustainable development, algorithm is developed. The use of the latter involves: continuous grouping and identification of the most significant threats and risks (in a closed cycle of management, organizational and economic, forecasting, analytical and econometric procedures); development of measures to eliminate the consequences of turbulent shifts.

A novel type of system for the deposition of ALD Al2O3 films is described. Wafers are transported in a linear track, floating on gas bearings without any physical contact with the track walls. During transport the wafers pass segments in which they come in contact with sequentially TMA, N2, H2O and N2. The system is made up of a large quantity of such ALD cells, each of which has a typical length of 12cm; in each of these cells 0.12nm Al2O3 is deposited. The dimensions of the pre-cursor injection lines and the pressures and flows are selected such that no mixing of the precursors take place inside the system. This results in a system that operates under atmospheric conditions with a throughput of 3600 wafers per hour, with easy automation, no moving parts (except the wafers) and no deposition on the track walls. Al2O3 films with thicknesses in the range 5-24nm were deposited with the following electrical performance: effective lifetimes on 200 μm thick FZ wafers in the range 1.5-2.5ms, dropping to 0.6-0.8ms after a firing-type anneal and on CZ wafers 0.2-0.7ms after firing. 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 1640-1644

Subsynchronous oscillation (SSO) usually caused by series compensation, power system stabilizer (PSS), high voltage direct current transmission (HVDC) and other power electronic equipment, which will affect the safe operation of generator shafting even the system. It is very important to identify the modal parameters of SSO to take effective control strategies as well. Since the identification accuracy of traditional methods are not high enough, the stochastic subspace identification (SSI) method is proposed to improve the identification accuracy of subsynchronous oscillation modal. The stochastic subspace identification method was compared with the other two methods on subsynchronous oscillation IEEE benchmark model and Xiang-Shang HVDC system model, the simulation results show that the stochastic subspace identification method has the advantages of high identification precision, high operation efficiency and strong ability of anti-noise.

Peer-reviewed journal article Applied Rheology

A lot of research has been done on the adoption of electric vehicles and on the deployment of the infrastructure for charging the batteries of these vehicles. Currently the total number of installed charging points keeps growing due to both public and private investments. Often charging services are offered as free service extensions. Maintaining this free business model will be difficult on the long term because of the investments needed. Therefore, the long term business viability and durability is not always clear from an investor point of view. This work presents a techno-economic model that describes the expected cost and revenue evolution resulting from different deployment strategies for a municipal or private parking facility operator. For charging service providers, charging pole exploiters and infrastructure owners for electric vehicle charging, the model allows to project the expected profitability. The main findings from this research indicate that business cases for public charging infrastructure can be viable, durable and could be competitive with the costs for charging the electric vehicle at home. Also, in a multi-actor market model all actors involved could benefit from deploying electric vehicle charging infrastructure. Although the business cases will be positive, significant investments are needed. European Journal of Transport and Infrastructure Research, Vol 14 No 4 (2014)

The use of Urea–Ammonia Mixture (UAM), 32% contributes to an in–crease in the productivity of agricultural land, with a decrease in the cost per unit of production of fodder and other crops. The composition and ratio of components, UAM, 32% contains three forms of nitrogen–ammonia (25%), amide (50%) and nitrate (25%), due to which the fertilizer acts for a long time, and vegetative alfalfa plants are provided with nitrogen throughout the growing season of the crop. The cost of nitrogen in UAM, 32% is the lowest, since its losses when using UAM, 32% on alfalfa do not exceed 10% of the total content. When applying UAM, 32%, the stability of organic diversity, characterized by a positive evolutionary process and adaptability of a complex of organisms associated with external factors of the environment without violations of the ratios of dominant species of organisms, was established. UAM, 32% does not affect levels of global biodiversity, with abiotic levels of agrocenoses, which provide optimal indicators of the circulation of substances, energy and information, as well as mechanisms for preserving the ecological niche and conditions for the existence of a diversity of biota.