低复杂度水声多输入多输出正交时频空调制通信方法研究

在多输入多输出正交时频空调制(MIMO-OTFS)水声通信系统中,基于消息传递(MP)算法的MIMO-OTFS通信的计算复杂度较高,在实际应用中会增加设备成本。针对上述问题,该文提出一种基于2维虚拟时间反转镜(VTRM)的MIMO-OTFS均衡算法,该算法利用VTRM的时频空聚焦特性,有效提高了均衡性能,并通过改进的2维比例归一化最小均方(IPNLMS)算法进行信道估计,该算法利用时延-多普勒域信道的稀疏特性以较低的复杂度提高了收敛速度,最后通过2维自适应判决反馈均衡算法消除残余的码间串扰,进一步提高系统性能。仿真结果表明,所提均衡算法具有可行性,且在保证相同性能时,复杂度低于MP算法。     

电磁开腔品质因数Q的计算

本文对电磁开腔镜面反射损耗、镜面衍射损耗、耦合孔损耗在各种模式下引起的品质因数进行了深入的理论分析,得到了品质因数更为精确的计算公式,最后给出了计算实例。     

Collaborative distributed sun-tracking control system for building integration with minimal plant area and maximum energy-conversion efficiency

This paper presents a collaborative distributed sun-tracking control system for a novel Fixed Mirror Solar Concentrator (FMSC) structure, which increases the energy-conversion efficiency of the FMSC and reduces the space between solar collectors units, a positive aspect for in-building integration. The improved FMSC uses solar concentration collectors suited for mid-range thermal applications (90–200 °C) and is designed for easy installation in buildings because of its relatively small extension. The proposed solar orientation system (ORSYS) relies on a two-step algorithm to increase the energy captured by the receiver, which provides tolerance to common logical and mechanical errors in the estimation of the receiver position. ORSYS is implemented as a CAN-based distributed system, extended with web-interface features for supervision and configuration of the overall system. ORSYS also includes a coordination algorithm that allows adjacent collectors to share the physical space between them, thus reducing the total plant area. Experimental evaluation has been performed using an industrial-scale solar collector prototype, showing its feasibility and efficiency in terms of energy conversion in real environments.     

Relay protection mirror operation technology based on digital twin

When conducting relay protection research, research costs can be signifcantly reduced if protection principle development, protection parameter verifcation and debugging can be carried out without relying on actual protection devices. The concept of ‘digital twin’ has made this possible, but the existing research has shortcomings in real-time data interaction ability, protection logic transparency, interface standardization, human–computer interaction etc., and consequently,mirror operation of relay protection in digital space has not been fully realized. Therefore, referring to the characteristics of digital twin, and combining with the practical application requirements in relay protection, this paper proposes the concept and characteristics of relay protection mirror operation based on digital twin. Key solutions are proposed to address the difculties that may be encountered in the implementation of relay protection mirror operation in terms of protection principles, interfaces, real-time operation of the system, and human–computer interaction function simulation. Finally, an example of 110 kV double-bus and double-branch bus protection is used to verify the feasibility and progressiveness of the scheme proposed in this paper by comparing the action behavior and external characteristics of the twin protection and the actual protection device. The presented research can provide a reference for further in-depth research and application of relay protection using digital means.     

Relay protection mirror operation technology based on digital twin

When conducting relay protection research, research costs can be signifcantly reduced if protection principle development, protection parameter verifcation and debugging can be carried out without relying on actual protection devices. The concept of ‘digital twin’ has made this possible, but the existing research has shortcomings in real-time data interaction ability, protection logic transparency, interface standardization, human–computer interaction etc., and consequently,mirror operation of relay protection in digital space has not been fully realized. Therefore, referring to the characteristics of digital twin, and combining with the practical application requirements in relay protection, this paper proposes the concept and characteristics of relay protection mirror operation based on digital twin. Key solutions are proposed to address the difculties that may be encountered in the implementation of relay protection mirror operation in terms of protection principles, interfaces, real-time operation of the system, and human–computer interaction function simulation. Finally, an example of 110 kV double-bus and double-branch bus protection is used to verify the feasibility and progressiveness of the scheme proposed in this paper by comparing the action behavior and external characteristics of the twin protection and the actual protection device. The presented research can provide a reference for further in-depth research and application of relay protection using digital means.     

利用“智能镜面”以18层代替30层以上住宅的节地设想

提出利用“智能镜面”辅助住宅主动获得日照,并在此基础上用18层的住宅代替目前居住区普遍应用的30层以上住宅,建设“合院式居住区”,以节约建设用地并形成“小街巷、密路网”的生活性街道.以北京某居住区为例进行重新规划设计,通过分析研究发现,该设想具有显著的节地效果,经济效益突出,其户型能满足安全疏散、视线卫生以及日照等相关...