随着医学教育改革的不断推进,以学生为中心,以成果导向教育(outcome based education, OBE)为目标,构建的新型教学模式越来越受到重视。组织和细胞培养技术是基础与临床各学科进行科研创新实践与生产的必备基础。本文通过探索在OBE理念...随着医学教育改革的不断推进,以学生为中心,以成果导向教育(outcome based education, OBE)为目标,构建的新型教学模式越来越受到重视。组织和细胞培养技术是基础与临床各学科进行科研创新实践与生产的必备基础。本文通过探索在OBE理念指导下,虚拟仿真教学模式在组织和细胞培养技术课程中的应用。为探索医学基础课程,尤其是偏重实践型课程教学提供新思路与新模式。展开更多
Although computer capabilities have been improved significantly, a large-scale virtual reality （VR） system demands much more in terms of memory and computation than the current computer systems can offer. This paper...Although computer capabilities have been improved significantly, a large-scale virtual reality （VR） system demands much more in terms of memory and computation than the current computer systems can offer. This paper discusses two important issues related to VR performance and applications in building navigation. These are dynamic loading of models based on cell segmentation for the optimal VR operation, and the route optimization based on path planning for easy navigation. The VR model of engineering and information technology complex （EITC） building at the University of Manitoba is built as an example to show the feasibility of the proposed methods. The reality, enhanced by three-dimensional （3D） real-time interactivity and visualization, leads navigators into a state of the virtual building immersion.展开更多
In the last decade, increasing applications of information technology (IT) within power industry has become a significant reality. As distributed power networks are gaining importance and renewables are getting a bigg...In the last decade, increasing applications of information technology (IT) within power industry has become a significant reality. As distributed power networks are gaining importance and renewables are getting a bigger ratio within energy production, Smart Grid applications have become essential, especially due to the intermittent nature of renewable energy resources. Smart Grid is a sustainable energy system that measures, checks, and controls the generation, transmission, and consumption of electrical energy in grids on all voltage levels. Smart Grid experts are driving forward the development of effective communication and information technologies for the build-up of intelligent power supply networks. Examples of these are control systems for the realization of virtual power plants, intelligent consumer data acquisition systems, and smart distribution management systems. Fuel cell-based hydrogen electricity, in comparison to other renewable energy sources, is more stable and predictable. Yet hydrogen power and smart-grids have many application points, mainly as means of energy storage. This study claims that hydrogen energy and smart-grids could also engage through an appliance of IT managed metering of hydrogen power production. Smart metering and management of hydrogen fuel cells would enable advanced planning of short-to-mid-term power productions and thus foster use of hydrogen power within distributed networks, as local community or industrial applications.展开更多
A virtual cathode oscillator （VCO） with a resonant cavity is presented and investigated numerically and theoretically, and its efficiency and stability are enhanced. An equivalent circuit method is introduced to ana...A virtual cathode oscillator （VCO） with a resonant cavity is presented and investigated numerically and theoretically, and its efficiency and stability are enhanced. An equivalent circuit method is introduced to analyze the resonant cavity com- posed of anode foil and feedback annulus, and a theoretical expression for the fundamental mode frequency of the resonant cavity is given. The VCO is investigated in detail with a particle-in-cell method. We obtain the microwave frequencies from simulation, theoretical expression, and relative references, and draw three important conclusions. First, the microwave fre- quency is a constant when the diode voltage is changed from 588 kV to 717 kV. Second, the fluctuation of the microwave frequency is very small when the AK gap is changed from 1.2 cm to 1.6 cm. Third, the microwave frequency agrees with the theoretical result. The relative error, which is calculated according to the theoretical and simulation frequencies, is only 1.7%.展开更多
文摘含氢燃料电池的微电网在孤岛运行时,仅采用虚拟同步发电机(virtual synchronous generator,VSG)控制技术作为外环无法达到理想的控制效果。线性自抗扰控制(linear active disturbance rejection control,LADRC)的引入提高微电网系统的抗扰能力,但传统LADRC中的线性扩张状态观测器(linear extend state observer,LESO)只具备观测阶跃信号的能力,而非线性扰动需要系统能够对周期信号进行跟踪和抑制。因此,提出基于重复控制的改进LADRC策略。利用重复控制能够对周期输入信号和扰动零误差跟踪补偿的特性,将其引入LADRC的LESO中改善系统的观测性能。对比分析LESO和基于重复控制的LESO的误差传递函数伯德图,并通过MATLAB/Simulink仿真平台验证该策略对于抑制非线性扰动的优越性。
文摘随着医学教育改革的不断推进,以学生为中心,以成果导向教育(outcome based education, OBE)为目标,构建的新型教学模式越来越受到重视。组织和细胞培养技术是基础与临床各学科进行科研创新实践与生产的必备基础。本文通过探索在OBE理念指导下,虚拟仿真教学模式在组织和细胞培养技术课程中的应用。为探索医学基础课程,尤其是偏重实践型课程教学提供新思路与新模式。
基金supported by Discovery Grants of National Science and Engineering Research Council of Canada (NSERC) and Faculty of Engineering at University of Manitoba
文摘Although computer capabilities have been improved significantly, a large-scale virtual reality （VR） system demands much more in terms of memory and computation than the current computer systems can offer. This paper discusses two important issues related to VR performance and applications in building navigation. These are dynamic loading of models based on cell segmentation for the optimal VR operation, and the route optimization based on path planning for easy navigation. The VR model of engineering and information technology complex （EITC） building at the University of Manitoba is built as an example to show the feasibility of the proposed methods. The reality, enhanced by three-dimensional （3D） real-time interactivity and visualization, leads navigators into a state of the virtual building immersion.
文摘In the last decade, increasing applications of information technology (IT) within power industry has become a significant reality. As distributed power networks are gaining importance and renewables are getting a bigger ratio within energy production, Smart Grid applications have become essential, especially due to the intermittent nature of renewable energy resources. Smart Grid is a sustainable energy system that measures, checks, and controls the generation, transmission, and consumption of electrical energy in grids on all voltage levels. Smart Grid experts are driving forward the development of effective communication and information technologies for the build-up of intelligent power supply networks. Examples of these are control systems for the realization of virtual power plants, intelligent consumer data acquisition systems, and smart distribution management systems. Fuel cell-based hydrogen electricity, in comparison to other renewable energy sources, is more stable and predictable. Yet hydrogen power and smart-grids have many application points, mainly as means of energy storage. This study claims that hydrogen energy and smart-grids could also engage through an appliance of IT managed metering of hydrogen power production. Smart metering and management of hydrogen fuel cells would enable advanced planning of short-to-mid-term power productions and thus foster use of hydrogen power within distributed networks, as local community or industrial applications.
基金supported by the National Natural Science Foundation of China(Grant No.11075210)the Postdoctoral Science Foundation of China(GrantNo.201104761)
文摘A virtual cathode oscillator （VCO） with a resonant cavity is presented and investigated numerically and theoretically, and its efficiency and stability are enhanced. An equivalent circuit method is introduced to analyze the resonant cavity com- posed of anode foil and feedback annulus, and a theoretical expression for the fundamental mode frequency of the resonant cavity is given. The VCO is investigated in detail with a particle-in-cell method. We obtain the microwave frequencies from simulation, theoretical expression, and relative references, and draw three important conclusions. First, the microwave fre- quency is a constant when the diode voltage is changed from 588 kV to 717 kV. Second, the fluctuation of the microwave frequency is very small when the AK gap is changed from 1.2 cm to 1.6 cm. Third, the microwave frequency agrees with the theoretical result. The relative error, which is calculated according to the theoretical and simulation frequencies, is only 1.7%.
