In this paper, we conduct research on the development of mechanical and electrical integration of system function principle and related technologies. Along with the rapid and continuous development of modem science an...In this paper, we conduct research on the development of mechanical and electrical integration of system function principle and related technologies. Along with the rapid and continuous development of modem science and technology, it ' s for the penetration and cross of different subjects great push, the more important is caused by technological revolution in the field of engineering and mechanical engineering field under the rapid development of computer technology and microelectronic technology and penetration to the mechanical and electrical integration, which is formed by the mechanical industry lead to trigger a particularly large changes in the mechanical industry management system and mode of production, product and technical structure, composition and function, thus result in industrial production from the previous mechanical electrification progressively electromechanical integration which lead the trend of the current technology.展开更多
Determination of rock mechanical parameters is the most important step in rock mass quality evaluation and has significant impacts on geotechnical engineering practice.Rock mass integrity coefficient(KV)is one of the ...Determination of rock mechanical parameters is the most important step in rock mass quality evaluation and has significant impacts on geotechnical engineering practice.Rock mass integrity coefficient(KV)is one of the most efficient parameters,which is conventionally determined from boreholes.Such approaches,however,are time-consuming and expensive,offer low data coverage of point measurements,require heavy equipment,and are hardly conducted in steep topographic sites.Hence,borehole approaches cannot assess the subsurface thoroughly for rock mass quality evaluation.Alternatively,use of geophysical methods is non-invasive,rapid and economical.The proposed geophysical approach makes useful empirical correlation between geophysical and geotechnical parameters.We evaluated the rock mass quality via integration between KV measured from the limited boreholes and inverted resistivity obtained from electrical resistivity tomography(ERT).The borehole-ERT correlation provided KV along various geophysical profiles for more detailed 2D/3D(two-/three-dimensional)mapping of rock mass quality.The subsurface was thoroughly evaluated for rock masses with different engineering qualities,including highly weathered rock,semi-weathered rock,and fresh rock.Furthermore,ERT was integrated with induced polarization(IP)to resolve the uncertainty caused by water/clay content.Our results show that the proposed method,compared with the conventional approaches,can reduce the ambiguities caused by inadequate data,and give more accurate insights into the subsurface for rock mass quality evaluation.展开更多
Photovoltaic (PV) modules have emerged as an ideal technology of choice for <span>harvesting vastly available renewable energy resources. However, the effi</span>ciency <span>of PV modules remains si...Photovoltaic (PV) modules have emerged as an ideal technology of choice for <span>harvesting vastly available renewable energy resources. However, the effi</span>ciency <span>of PV modules remains significantly lower than that of other renewable</span> energy sources such as wind and hydro. One of the critical elements affecting a photovoltaic module’s efficiency is the variety of external climatic conditions under which it is installed. In this work, the effect of simulated snow loads was evaluated on the performance of PV modules with different <span>types of cells and numbers of busbars. According to ASTM-1830 and IEC-1215</span> standards, a load of 5400 Pa was applied to the surface of PV modules for 3 hours. An indigenously developed pneumatic airbag test setup was used for the uniform application of this load throughout the test, which was validated by load cell and pressure gauge. Electroluminescence (EL) imaging and solar flash tests were performed before and after the application of load to characterize the performance and effect of load on PV modules. Based on these tests, the maxi<span>mum power output, efficiency, fill factor and series resistance were deter</span>mined. The results show that polycrystalline modules are the most likely to withstand the snow loads as compared to monocrystalline PV modules. A maximum drop of 32.13% in the power output and a 17.6% increase in series resistance were observed in the modules having more cracks. These findings demonstrated the efficacy of the newly established test setup and the potential of snow loads for reducing the overall performance of PV module.展开更多
After solution treatment, the 1420 Al-Li alloy samples were aged at different temperatures in an electric field with different intensity. The measurements made showed that the electric field increased the strength of ...After solution treatment, the 1420 Al-Li alloy samples were aged at different temperatures in an electric field with different intensity. The measurements made showed that the electric field increased the strength of the 1420 Al-Li alloy, and best properties were obtained when they were aged at 120 ℃ with E=4 kV/cm for 12 hrs. The electric field promoted the nucleation of δ′ phase, increased the quantity of the δ′ phase, and made the size of the δ′ phase particles smaller. The electric field restrained the formation and growth of PFZ, and increased the intensity of the electric field while the width of the PFZ was decreased.展开更多
The thermoelectric properties of Sr0.61Ba0.39Nb2O6-δ ceramics, reduced in different conditions, are investigated in the temperature range from 323 K to 1073 K. The electrical transport behaviors of the samples are do...The thermoelectric properties of Sr0.61Ba0.39Nb2O6-δ ceramics, reduced in different conditions, are investigated in the temperature range from 323 K to 1073 K. The electrical transport behaviors of the samples are dominated by the thermal-activated polaron hopping in the low temperature range, the Fermi glass behavior in the middle temperature range, and the Anderson localized behavior in the high temperature range. The thermal conductivity presents a plateau at high- temperatures, indicating a glass-like thermal conduction behavior. Both the thermoelectric power factor and the thermal conductivity increase with the increase of the degree of oxygen-reduction. Taking these two factors into account, the oxygen-reduction can still contribute to promoting the thermoelectric figure of merit. The highest ZT value is obtained to be -0.19 at 1073 K in the heaviest oxygen reduced sample.展开更多
The European Union (EU) this year has entered into the next phase of its existence, not only in terms of new economic conditions of the unwinding of the financial and economic crisis, but also on the basis of the re...The European Union (EU) this year has entered into the next phase of its existence, not only in terms of new economic conditions of the unwinding of the financial and economic crisis, but also on the basis of the results of European Parliament elections and the adoption of the EU financial fi'amework for the period from 2014 to 2020. These indisputable facts does not change our view of the situation in which the EU is, or at major tasks whose managing can be considered as condition of its continued existence as an important part of the global economy. As the fundamental problem of the EU, persisting differences in economic level of the member states is considered. The aim of this paper is not to formulate and even to propose how the EU should look like in the future, but to assess criteria of decision making about concept of its future direction. In this context, the verification of argument will be performed, that only the integration of the countries that have common interests and objectives respectively are able to make the same efforts to meet them, is in certain stages of integration possible and functional. Conversely, a broader territorial structured integration of countries with significantly different economic parameters is feasible and functional only at lower stages of integration. This paper starts from that the process of economic convergence among member states as a condition for integration can be realized at the lower stage of the integration process, in terms of economic and monetary union, then only the expense of reducing the dynamics of economic development of integration group as a whole. Some degree of equilibrium of economic levels represents an important condition for the success of the integration project. To meet this goal, current differences in economic level of individual EU member states (comparative analysis using indicators of growth rate and development of GDP/capita) will be analyzed, including the assessment of the cost of the EU for the implementation of cohesion policy, both in terms of the economic crisis and the phase of requirement to the revival of the European economy. In this context, also the effectiveness of institutional arrangements of decision-making procedures will be assessed.展开更多
为提高综合能源系统(integrated energy system, IES)低碳规划及优化运行的技术水平,推进能源结构低碳转型及新型电力系统建设,梳理和总结研究学者在IES的模型构建、系统规划、运行调度等方面的研究成果,该文开展了相关领域的综述研究...为提高综合能源系统(integrated energy system, IES)低碳规划及优化运行的技术水平,推进能源结构低碳转型及新型电力系统建设,梳理和总结研究学者在IES的模型构建、系统规划、运行调度等方面的研究成果,该文开展了相关领域的综述研究。首先,阐述了综合能源系统的典型架构、典型设备及其能流特性。其次,针对IES低碳规划和运行策略及其相关支撑技术,分别论述了多态不确定性模型及功率预测、柔性负荷调控策略、IES参与电力辅助服务及其低碳运营机制、优化模型及其求解算法等方面的技术路线及研究成果;研究表明,规划与运行策略是支撑IES低碳、高效、经济运行水平的关键技术,计及不确定性的高维、非线性、多目标、非凸问题的精确建模和快速求解等难点问题亟待深入研究。最后,展望了人工智能、大数据、电力物联网等新技术在IES低碳规划和运行方面的应用前景,归纳了该领域亟待应对的技术挑战和关键问题。展开更多
文摘In this paper, we conduct research on the development of mechanical and electrical integration of system function principle and related technologies. Along with the rapid and continuous development of modem science and technology, it ' s for the penetration and cross of different subjects great push, the more important is caused by technological revolution in the field of engineering and mechanical engineering field under the rapid development of computer technology and microelectronic technology and penetration to the mechanical and electrical integration, which is formed by the mechanical industry lead to trigger a particularly large changes in the mechanical industry management system and mode of production, product and technical structure, composition and function, thus result in industrial production from the previous mechanical electrification progressively electromechanical integration which lead the trend of the current technology.
基金supported by Xinjiang Key Laboratory of Geohazards Prevention(Grant No.XKLGP2022K07)Key R&D Program of Xinjiang Uygur Autonomous Region(Grant No.2022B03001-2)the Third Xinjiang Scientific Expedition Program(Grant No.2022xjkk1305).
文摘Determination of rock mechanical parameters is the most important step in rock mass quality evaluation and has significant impacts on geotechnical engineering practice.Rock mass integrity coefficient(KV)is one of the most efficient parameters,which is conventionally determined from boreholes.Such approaches,however,are time-consuming and expensive,offer low data coverage of point measurements,require heavy equipment,and are hardly conducted in steep topographic sites.Hence,borehole approaches cannot assess the subsurface thoroughly for rock mass quality evaluation.Alternatively,use of geophysical methods is non-invasive,rapid and economical.The proposed geophysical approach makes useful empirical correlation between geophysical and geotechnical parameters.We evaluated the rock mass quality via integration between KV measured from the limited boreholes and inverted resistivity obtained from electrical resistivity tomography(ERT).The borehole-ERT correlation provided KV along various geophysical profiles for more detailed 2D/3D(two-/three-dimensional)mapping of rock mass quality.The subsurface was thoroughly evaluated for rock masses with different engineering qualities,including highly weathered rock,semi-weathered rock,and fresh rock.Furthermore,ERT was integrated with induced polarization(IP)to resolve the uncertainty caused by water/clay content.Our results show that the proposed method,compared with the conventional approaches,can reduce the ambiguities caused by inadequate data,and give more accurate insights into the subsurface for rock mass quality evaluation.
文摘Photovoltaic (PV) modules have emerged as an ideal technology of choice for <span>harvesting vastly available renewable energy resources. However, the effi</span>ciency <span>of PV modules remains significantly lower than that of other renewable</span> energy sources such as wind and hydro. One of the critical elements affecting a photovoltaic module’s efficiency is the variety of external climatic conditions under which it is installed. In this work, the effect of simulated snow loads was evaluated on the performance of PV modules with different <span>types of cells and numbers of busbars. According to ASTM-1830 and IEC-1215</span> standards, a load of 5400 Pa was applied to the surface of PV modules for 3 hours. An indigenously developed pneumatic airbag test setup was used for the uniform application of this load throughout the test, which was validated by load cell and pressure gauge. Electroluminescence (EL) imaging and solar flash tests were performed before and after the application of load to characterize the performance and effect of load on PV modules. Based on these tests, the maxi<span>mum power output, efficiency, fill factor and series resistance were deter</span>mined. The results show that polycrystalline modules are the most likely to withstand the snow loads as compared to monocrystalline PV modules. A maximum drop of 32.13% in the power output and a 17.6% increase in series resistance were observed in the modules having more cracks. These findings demonstrated the efficacy of the newly established test setup and the potential of snow loads for reducing the overall performance of PV module.
文摘After solution treatment, the 1420 Al-Li alloy samples were aged at different temperatures in an electric field with different intensity. The measurements made showed that the electric field increased the strength of the 1420 Al-Li alloy, and best properties were obtained when they were aged at 120 ℃ with E=4 kV/cm for 12 hrs. The electric field promoted the nucleation of δ′ phase, increased the quantity of the δ′ phase, and made the size of the δ′ phase particles smaller. The electric field restrained the formation and growth of PFZ, and increased the intensity of the electric field while the width of the PFZ was decreased.
基金Project supported by the National Basic Research Program of China(Grant No.2013CB632506)the National Natural Science Foundation of China(Grant Nos.51202132 and 51002087)
文摘The thermoelectric properties of Sr0.61Ba0.39Nb2O6-δ ceramics, reduced in different conditions, are investigated in the temperature range from 323 K to 1073 K. The electrical transport behaviors of the samples are dominated by the thermal-activated polaron hopping in the low temperature range, the Fermi glass behavior in the middle temperature range, and the Anderson localized behavior in the high temperature range. The thermal conductivity presents a plateau at high- temperatures, indicating a glass-like thermal conduction behavior. Both the thermoelectric power factor and the thermal conductivity increase with the increase of the degree of oxygen-reduction. Taking these two factors into account, the oxygen-reduction can still contribute to promoting the thermoelectric figure of merit. The highest ZT value is obtained to be -0.19 at 1073 K in the heaviest oxygen reduced sample.
文摘The European Union (EU) this year has entered into the next phase of its existence, not only in terms of new economic conditions of the unwinding of the financial and economic crisis, but also on the basis of the results of European Parliament elections and the adoption of the EU financial fi'amework for the period from 2014 to 2020. These indisputable facts does not change our view of the situation in which the EU is, or at major tasks whose managing can be considered as condition of its continued existence as an important part of the global economy. As the fundamental problem of the EU, persisting differences in economic level of the member states is considered. The aim of this paper is not to formulate and even to propose how the EU should look like in the future, but to assess criteria of decision making about concept of its future direction. In this context, the verification of argument will be performed, that only the integration of the countries that have common interests and objectives respectively are able to make the same efforts to meet them, is in certain stages of integration possible and functional. Conversely, a broader territorial structured integration of countries with significantly different economic parameters is feasible and functional only at lower stages of integration. This paper starts from that the process of economic convergence among member states as a condition for integration can be realized at the lower stage of the integration process, in terms of economic and monetary union, then only the expense of reducing the dynamics of economic development of integration group as a whole. Some degree of equilibrium of economic levels represents an important condition for the success of the integration project. To meet this goal, current differences in economic level of individual EU member states (comparative analysis using indicators of growth rate and development of GDP/capita) will be analyzed, including the assessment of the cost of the EU for the implementation of cohesion policy, both in terms of the economic crisis and the phase of requirement to the revival of the European economy. In this context, also the effectiveness of institutional arrangements of decision-making procedures will be assessed.
文摘为提高综合能源系统(integrated energy system, IES)低碳规划及优化运行的技术水平,推进能源结构低碳转型及新型电力系统建设,梳理和总结研究学者在IES的模型构建、系统规划、运行调度等方面的研究成果,该文开展了相关领域的综述研究。首先,阐述了综合能源系统的典型架构、典型设备及其能流特性。其次,针对IES低碳规划和运行策略及其相关支撑技术,分别论述了多态不确定性模型及功率预测、柔性负荷调控策略、IES参与电力辅助服务及其低碳运营机制、优化模型及其求解算法等方面的技术路线及研究成果;研究表明,规划与运行策略是支撑IES低碳、高效、经济运行水平的关键技术,计及不确定性的高维、非线性、多目标、非凸问题的精确建模和快速求解等难点问题亟待深入研究。最后,展望了人工智能、大数据、电力物联网等新技术在IES低碳规划和运行方面的应用前景,归纳了该领域亟待应对的技术挑战和关键问题。