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In recent years, in order to promote the independent development of the new energy vehicle industry, Chinese government has decided to reduce the consumption subsidies for new energy vehicles until the subsidies are completely withdrawn. The reduction of consumption subsidy has a great impact on the production and sales of new energy vehicles in the whole vehicle market. However, does the reduction of this subsidy also have an impact on other enterprises in the new energy vehicles industry chain? This paper tests this problem using data from 2016 to 2018, and finds, through empirical analysis, that during the period of subsidy decline, the profitability of component enterprises is significantly positively correlated with this subsidies, while the r&d investment of enterprises is significantly negatively correlated with this subsidies. The results show that in terms of profitability, the reduction of consumer subsidies not only has an impact on the whole vehicle industry of new energy vehicles, but also has an adverse impact on the core component companies in the industrial chain. However, in terms of r&d, the reduction of subsidies has more negatively strengthened the input and attention of R&D in component companies.

Nowadays, much attention is payed to the development of renewable energy resources. Wind energy plays a major role in this issue. That is why there is a growing interest for improving the design process of wind turbines at many aspects. This study compares two types of offshore wind turbines structures, the monopile and the jacket structure, in their dependency on wave load characteristics’ variations. The examined wave characteristics are significant wave height and wave peak period. The jacket structure showed lower influence of increase of wave height to stresses in the cross section at the bottom of the structure compared to the monopile structure. The monopile structure showed slight dependency of stresses on increasing wave frequency, while the jacket structure showed nearly no dependency, due to its more complex geometry and higher stiffness.

We have attained superior quality a-SiGe:H and nc-Si:H materials deposited at high rate, ~0.6 nm/s for a-SiGe:H and 1-1.5 nm/s for nc-Si:H, and achieved improved multi-junction solar cell performance. For a-SiGe:H based cells, we have focused our effort on further improving the a-SiGe:H film quality by carefully optimizing process parameters, particularly with Ge content and profile, hydrogen dilution, deposition pressure and substrate-tocathode distance, to fabricate a-SiGe:H films with low defect density and good stability. For nc-Si:H based solar cells, we have mainly worked on improving the spatial uniformity and homogeneous properties for nc-Si:H deposition, and on optimizing the plasma process and selecting species to deposit further improved nc-Si:H. We attained 10.1% and 11.2% stabilized efficiencies, respectively, for large-area (≥400 cm2) encapsulated a-Si:H/a-SiGe:H/a-SiGe:H and a- Si:H/nc-Si:H/nc-Si:H triple-junction cells. Comparison between a-SiGe:H and nc-Si:H based technologies and future improvement will be presented. 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 2783-2787

This article addresses the problem that fluctuations in the torque of an internal combustion engine (ICE) lead to additional energy losses, as it causes fluctuations in the speed and kinetic energy of the car. These losses increase as the frequency of oscillations of the torque of the internal combustion engine approaches the frequency of free (natural oscillations) of the running gear of the car in the longitudinal direction. If there is an elastic connection between the traction force and the movement of the car, the movement of the latter can be represented as complex. At the same time, the portable movement is uniform, and the relative movement is oscillatory. This article presents the results of the study of these losses for cars with mechanical and combined electromechanical drive wheels. Analytical expressions are obtained, which allows to take into account additional energy losses including the tangential rigidity of the tire and the rigidity of the suspension in the longitudinal direction. When using a combined electromechanical drive of the drive wheels as well as in the case of a mechanical transmission of a car, the resonance is dangerous. But with the increase in the share of torque kem on the wheel generated by the electric motor, the relative additional energy losses for the movement of the car are reduced.

This paper presents a research work carried out under the umbrella of the CASCADE project, which is a European FP7 research project which is developing facility-specific measurement-based energy action plans for the airport energy managers that are underpinned by Fault Detection Diagnosis (FDD). The paper first describes the context of the project then it focuses on Building Management Systems describing the current status of the technology and presenting an outlook on their future development. Then a Strengths Weakness Opportunity and Treads (SWOT) framework is defined with the aim of verifying the suitability of an installed BMS system to incorporate Fault Detection and Diagnosis (FDD) tools

Programmed Logic Controller (PLC) is the digital calculation operation system, which is specially designed for industrial working environment. This paper proposed the implement of hydraulic control system for large-scale railway maintenance equipment based on PLC. This implement pursued the purpose of accurate control of hydraulic working units of large-scale railway maintenance equipment. Large-scale railway maintenance equipment should always work in efficient statement. Focusing on this requirement, the reliability design of hardware for current leakage and impulse current which is proposed in the paper is necessary. This paper proposed Triple Modular Redundancy (TMR) for relative horizontal check of working units linking bridge. This paper also proposed the method to prevent the current leakage and impulse current. As for hydraulic valves, this paper proposed PID algorithm to realize the control of Analogue Closed-Loop.

In order to develop the technology of carbon dioxide at so-called supercritical state (sCO2) further, quick and reliable design tools for the different system components, e.g. centrifugal compressors, are required. In this study, a computer program is developed to predict the performance of centrifugal compressors with sCO2 as working fluid. This computer program is based on mean-line analysis, calculates the fluid parameters at selected sections of the meridional plane and plots the performance maps. So-called enthalpy loss coefficients are utilized to describe the difference between the isentropic and the polytropic process. In addition to previous studies, the presented model intends to predict the performance of sCO2 centrifugal compressor with a shrouded impeller and a vaneless diffuser. For this purpose, corresponding loss coefficients are incorporated. Subsequently, the predicted results of this work are compared and validated with computational fluid dynamics (CFD) and experimental results from the EU-project sCO2-HeRo. The prediction of the computer program fits within 5% deviation to the CFD results, and about 4% to the experimental results regarding to pressure ratio. Conference Proceedings of the European sCO2 Conference4th European sCO2 Conference for Energy Systems: March 23-24, 2021, Online Conference, p. 68

It has to be considered that dynamic performance of Super Capacitor and Battery hybrid energy storage system is poor and the output waveform of AC voltage distorted seriously. The Third Harmonic Injection PWM (THIPWM) with the three-level inverter, which has a excellent performance to improve the dynamic performance of the super capacitor and battery, gathers information from ends of the DC output voltage or current and the total current of the DC side to solve the problem of unbalanced neutral line voltage of three-level inverter .It also keeps super capacitor and battery controlled smoothly during the operation, and reduces the final output waveform distortion index. The simulation results verify the practicality and correctness of the three-level inverter topology and its control algorithm.

The main parameters of the microclimate of pig farms are regulated by the norms of technological design. Naturally, such micro-climate parameters at real energy prices require high costs, but these are the most favourable conditions for the life of suckling piglets. According to the presented analysis, the problem of research is the need to provide a micro-climate in the room for comfortable keeping of pigs, which is currently achieved through high energy. The purpose of the development is to increase the efficiency of the microclimate of pig farms by using a mechatronic control system, rational use of utilized air energy and soil thermal potential with reduced energy costs of the ventilation system. The problem is solved by creating such a mechatronic system to ensure the microclimate of pig farms, which can: switch the direction of airflow to ensure the operation of the system in winter and summer; to control the movement of air, which must be disposed of according to the parameters of its quality; to provide a local microclimate in each place where animals are kept; rational use of soil thermal energy as a source of alternative energy; to carry out automatic pumping of the water necessary for humidification of air, and its utilization. The article presents the results of research of parameters of the developed mechatronic system of providing microclimate of pig premises, which were carried out in three stages: research of heat exchanger of side-evaporating type; substantiation of the ventilation system of polluted air intake; substantiation of the ventilation system for injecting clean air taking into account it's geothermal heating/cooling. The advantage of the proposed mechatronic system of the microclimate of pig farms is that it allows increasing the efficiency of microclimate by rational use of energy of utilized air (due to the use of side-evaporator type heat exchanger based on Maisotsenko cycle) and soil heat potential (geothermal energy) at low operating costs of the ventilation system through the additional provision of mechatronic elements. The presented results of numerical simulation of the indirect evaporative heat exchanger allow us to state that the cooling effect obtained in indirect evaporative channels can be quite high in comparison with traditional air conditioning patterns. The presented heat exchanger based on the Maisotsenko cycle (M-cycle) of considered heat carrier flow scheme is characterized by its high cost-effectiveness, low specific cost, small operational costs and structural simplicity, which is confirmed in the works. The models obtained in the Star CCM +software package can be used for optimization analysis of air-cooling with variations in the Reynolds number, humidity, channel length and geometric dimensions of channels. Because of analytical investigations of the contaminated air intake ventilation system, the method was developed and on its basis – the algorithm was implemented for the determination of geometrical arrangement of holes in the air duct of the mechatronic system for pigsty microclimate maintenance.

According to the characteristics of photovoltaic cell output power curve, this paper analyzed and explained the principle of Maximum Power Point Tracking (MPPT) and both advantages and disadvantages of constant voltage tracking method & perturbation observation method. Further, in combination with the advantages of existing maximum power tracking methods, this paper comes up with an improved tracking method which is recognized as maximum power point tracking combined with constant voltage tracking method & variable step-size perturbation observation method. The Simulink simulation results have proven this enhanced tracking method has a better performance in System response and steady state characteristics.