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Одним из способов исследования фазовых превращений в бризантных взрывчатых веществах (БВВ) является передача тепла посредством соприкосновения с ним нагретого до определенной температуры проводника. Чаще всего проводник нагревается посредством пропускания через него электрического тока. Однако в местах контакта происходит потеря части энергии, а поскольку определение тепловых параметров фазовых превращений ведется методами косвенного измерения, то учет обозначенных потерь приведет к уменьшению расчетной погрешности в ходе обработки экспериментальных данных. One of the ways to study phase transformations in high explosive substances (BVV) is the transfer of heat by means of contact with a conductor heated to a certain temperature. Most often, the conductor is heated by passing an electric current through it. However, part of the energy is lost at the points of contact, and since the thermal parameters of phase transformations are determined using indirect measurement methods, taking into account the indicated losses will reduce the calculated error during the processing of experimental data.

Coordinate pulsewidth modulation is considered for the control of power switches of matrix and two-component direct frequency converters (DFC) in ac drive systems. The synthesis of modulating signals yielding the specified output voltages and sinusoidal grid currents for converters with no intermediate smoothing filter is discussed. Simulation of DFC operation with an RLE load and an asynchronous motor is undertaken.

This study explores the use of energy savings technologies in timber production for wood housing construction. Methods applied were based on the creation of system of optimized regimes of drying of sawn timber was carried out in two stages: computing experiment with the tools of MathCAD and production experiment. The findings discovered the following tendency: however the minimum cost of energy is achieved at the minimum time of drying that is explained by an essential difference in the cost of thermal and electric energy. The regimes of steeples structure received by computer modeling allow receiving sawn timber that fully meets the requirements of the consumer without application of moisture treatment and the conditioning processing. The developed technique of formation of the steeples regimes of drying of sawn timber allows determining structure and sizes of parameters of the regime depending on the required quality of drying and energy costs on its carrying out. Calculations of technical and economic efficiency have shown that the total annual economic effect in more than 17 dollars per 1 m3 and it can be extended by including on power component. © 2018 CEUR-WS. All rights reserved. The work is carried out based on the task on fulfilment of government contractual work in the field of scientific activities as a part of base portion of the state task of the Ministry of Education and Science of the Russian Federation to Ural State Forest Engineering University (the # 26.8660.2017/8.9 "The Research Methodology of Forms of Economic and Technological Reality in the Aspect of Sustainable Forest Management").

The main performance characteristics of the turbine, descriptions of the electrohydraulic control and protection system (EHCPS), the heat flow diagram, arrangement decisions, and motivation for selecting them, are given. The steam turbine presented by the Ural Turbine Works (UTW) is intended for replacing the VPT-25 turbine the service life of which has already expired at the Novokuybyshevsk CHP plant. The mixed-pressure turbine will operate in combination of the double-circuit heat recovery boiler (HRB) in a parallel scheme. High-pressure (HP) steam will be supplied from the main steam header to which high-pressure steam from the power boilers and the HRB will be fed, while low-pressure (LP) steam will be supplied directly from the HRB. For the turbine, nozzle steam distribution and the two-row control stage are adopted. The turbine has a process steam extraction line with its stop and control valve and heating steam extraction line leading to the main steam collector.

The diffusion process in a multicomponent system can be formulated in a general form by the generalized Maxwell-Stefan equations. This formulation is able to describe the diffusion process in different systems, such as, for instance, bulk diffusion (in the gas, liquid, and solid phase) and diffusion in microporous materials (membranes, zeolites, nanotubes, etc.). The Maxwell-Stefan equations can be solved analytically (only in special cases) or by numerical approaches. Different numerical strategies have been previously presented, but the number of diffusing species is normally restricted, with only few exceptions, to three in bulk diffusion and to two in microporous systems, unless simplifications of the Maxwell-Stefan equations are considered. In the literature, a large effort has been devoted to the derivation of the analytic expression of the elements of the Fick-like diffusion matrix and therefore to the symbolic inversion of a square matrix with dimensions n x n (n being the number of independent components). This step, which can be easily performed for n = 2 and remains reasonable for n = 3, becomes rapidly very complex in problems with a large number of components. This paper addresses the problem of the numerical resolution of the Maxwell-Stefan equations in the transient regime for a one-dimensional system with a generic number of components, avoiding the definition of the analytic expression of the elements of the Fick-like diffusion matrix. To this aim, two approaches have been implemented in a computational code; the first is the simple finite difference second-order accurate in time Crank-Nicolson scheme for which the full mathematical derivation and the relevant final equations are reported. The second is based on the more accurate backward differentiation formulas, BDF, or Gear's method (Shampine, L. F. ; Gear, C. W. SIAM Rev. 1979, 21, 1.), as implemented in the Livermore solver for ordinary differential equations, LSODE (Hindmarsh, A. C. Serial Fortran Solvers for ODE Initial Value Problems, Technical Report; https://computation.llnl.gov/casc/odepack/odepack_ home.html (2006).). Both methods have been applied to a series of specific problems, such as bulk diffusion of acetone and methanol through stagnant air, uptake of two components on a microporous material in a model system, and permeation across a microporous membrane in model systems, both with the aim to validate the method and to add new information to the comprehension of the peculiar behavior of these systems. The approach is validated by comparison with different published results and with analytic expressions for the steady-state concentration profiles or fluxes in particular systems. The possibility to treat a generic number of components (the limitation being essentially the computational power) is also tested, and results are reported on the permeation of a five component mixture through a membrane in a model system. It is worth noticing that the algorithm here reported can be applied also to the Fick formulation of the diffusion problem with concentration-dependent diffusion coefficients.

Demand Response programs can allow residential electricity consumers to cut their energy bills. However, in case of contingencies in the energy system when the guaranteed peak load reduction is needed, comfort of consumers can be significantly deteriorated and they can choose to opt out. This paper investigates the possibility of peak load reduction and yet highly respecting consumers' comfort by coordinating a group of electric tank water heaters. The proposed peak shaving mechanism accounts for interests of both utility companies and their customers. It employs two optimization models tailored to the needs of both sides to optimally schedule individual water heaters. The suggested Simulation results show the potential of the proposed mechanism to provide the guaranteed peak load reduction thus contributing to the stability of the electrical grid, while transparent balancing between comfort-money and comfort-energy incorporated in the control scheme is of interest and use to green consumers.

Recently, a new composite "LiCl inside Multi-Wall Carbon NanoTubes" (LiCl/MWCNT) has been suggested as water sorbent for Adsorption Thermal Energy Storage (ATES), because it has a large thermal storage capacity of 1.7 kJ/g for a daily heat storage cycle. This work addresses the results of the study of water sorption dynamics on the novel composite loaded into representative small scale fragments of a common finned flat-tube HEx. The study consists of four parts: (1) shaping the LiCl/MWCNT composite as grains using polyvinyl alcohol (PVA) as a binder; (2) analysis of sorption equilibrium for the pair "LiCl/ MWCNT/PVA - water"; (3) measuring the thermal storage capacity of the granulated LiCl/ MWCNT/PVA composite; (4) investigation of water sorption dynamics on the LiCl/MWCNT/PVA under typical conditions of the daily storage cycle. It is shown that the thermal storage capacity of the LiCl/MWCNT/PVA composite equals 1.5-1.6 kJ/g. The specific power reaches 4.2 and 9.8 kW/kg of the heat release and thermal storage stages, respectively. The results obtained show that the working pair "LiCl/MWCNT/PVA - water" appears to be advantageous for ATES.

Cooperative Game Theory has recently attracted attention in power systems research as a tool for expansion planning analysis. However, this analysis is usually performed in an ex-post manner, i.e., planning and operation decisions are separated from the allocation mechanisms themselves. The existing paradigm implies selecting an allocation rule (say, the Shapley value) to share the value of cooperation and verifying its rationality (e.g., by checking the Core of the cooperative game). Additional metrics of coalitional stability are omitted. Such an ex-post approach could lead to coalitional stability issues, which may hamper the establishment of cooperation. For example, there could be a severe imbalance in players' positions, and the contribution of some players could be underestimated in the grand coalition. This paper proposes a bilevel optimization framework for explicitly incorporating Cooperative Game Theory principles into transmission expansion planning problems. Using a simple 4-system case study and a real-world case of cross-border power interconnections in Northeast Asia, we demonstrate that it is possible to make planning decisions in an anticipatory manner subject to the stability of coalitions. The identified expansion plans with enhanced coalitional stability indicate the ways of making parties more equally involved in electricity trading. Finally, we discuss the applicability of the bilevel TEP model, the properties of resulting cooperative games, and the compromise between coalitional stability and economic efficiency in transmission expansion planning.

Novel methods for enhancing collaboration and interactions are required to ensure that stakeholders and governments are able to develop a shared vision that supports sustainable watershed governance. Particular attention must be placed on integrating stakeholders who would otherwise have limited decision-making power. By crossing professional, ideological and jurisdictional boundaries, stakeholders' perspectives are more likely to change than when staying within those boundaries. This process, known as boundary crossing, requires boundary objects; either artifacts, people, or institutions that play a bridging role between different boundary spaces. For this study, serious games powered by scientific models are identified as potentially effective boundary objects. A serious game simulation called Aqua Republica was used to organize game simulation events allowing stakeholders to connect in an in-person, informal and novel setting. This exploratory research aims to study the role and impact of serious games as boundary objects to enhancing collaboration and knowledge co-creation. The following research questions are addressed: (1) Do interactions increase over the course of a game simulation event? (2) Does the quality of interactions change over the course of a game simulation event? (3) Are the quantity and quality of interactions affected by pre-existing relationships? And if so, how? (4) How does the relationship between participants change over the course of a game simulation event? As part of this study, four game simulation events were organized that included students, professionals and diverse stakeholder groups working in watershed management contexts across Eastern Canada with 40 participants in total. Participants were divided into teams of 3-5 members and were surveyed and their interactions recorded. An interaction and social network analysis of the audiovisual recordings of each game simulation event indicates that interactions between participants increase in both quantity and quality as the game progresses. The analysis shows that serious game simulations provide an intervention platform not only to facilitate cross-boundary interactions, but also to strengthen relationships between diverse stakeholders, as expressed by an increase in mutual trust and empathy, as well as an improved understanding among the participants of the watershed system and the complex issues at stake.