In view of the low ranging efficiency of the conventional fixed frame-length algorithm in the inter-satellite link,an adaptive frame-length algorithm is proposed. The frame length is adjusted adaptively according to t...In view of the low ranging efficiency of the conventional fixed frame-length algorithm in the inter-satellite link,an adaptive frame-length algorithm is proposed. The frame length is adjusted adaptively according to the results of ranging and velocity measuring to improve ranging efficiency. Buffers which enable the frame length to be selected discretely and adaptively are introduced to avoid frequent hopping of the frame-length.Frame length marker is created to automatically identify the frame-length for frame synchronization procedures in receivers. The feasibility and the validity of the proposed algorithm to improve the efficiency of ranging are verified through both theoretic analysis and simulation,and the efficiency improves up to 88% when there are five buffers. This improvement can be further enhanced by increasing the number of buffers. Proper allocation of inter-satellite buffers is required to make a balance between the ranging efficiency and the system complexity.展开更多
主动快门式3D技术的关键在于左右眼帧序的同步,尤其在无线及多人观看的条件下,帧序同步仍存在着很多问题。提出了一种在DLP Link 3D投影显示平台上利用红外光通信实现统一帧序同步的解决方案,旨在进一步提高DLP Link主动快门3D技术的易...主动快门式3D技术的关键在于左右眼帧序的同步,尤其在无线及多人观看的条件下,帧序同步仍存在着很多问题。提出了一种在DLP Link 3D投影显示平台上利用红外光通信实现统一帧序同步的解决方案,旨在进一步提高DLP Link主动快门3D技术的易用性和灵活性。展开更多
以欧姆龙公司CP1H型号的PLC为应用背景,设计了基于Host Link FINS协议的PLC设备远程监控系统。该文提出了基于串口的远程通信方案,并且详细分析了Host Link FINS协议的结构和指令格式,用MFC实现了监控软件的设计,完成监控软件与欧姆龙PL...以欧姆龙公司CP1H型号的PLC为应用背景,设计了基于Host Link FINS协议的PLC设备远程监控系统。该文提出了基于串口的远程通信方案,并且详细分析了Host Link FINS协议的结构和指令格式,用MFC实现了监控软件的设计,完成监控软件与欧姆龙PLC的数据通信功能,实现监控软件对PLC的远程监控。经过现场的测试和运行,该监控系统稳定可靠,性能较高。展开更多
为了增强传统钢框筒结构(Steel framed-tubed structures,SFT)的抗震性能和震后功能可恢复能力,提出了螺栓拼接连接可更换耗能梁段-钢框筒结构(Steel framed-tubed structures with bolt-splice-connected repairable link beams,SFT-R...为了增强传统钢框筒结构(Steel framed-tubed structures,SFT)的抗震性能和震后功能可恢复能力,提出了螺栓拼接连接可更换耗能梁段-钢框筒结构(Steel framed-tubed structures with bolt-splice-connected repairable link beams,SFT-RLB)。首先给出了SFT-RLB结构构件的设计方法;然后基于OpenSEES平台提出了整体结构的弹塑性数值模型建模方法,通过子结构试验结果验证了有限元模型的准确性;继而设计了SFT和SFT-RLB结构算例,对比了2种结构的弹性和弹塑性性能;最后采用IDA方法对结构算例的抗地震倒塌能力进行评估。分析结果表明,SFT-RLB结构主要通过耗能梁段发展塑性耗散地震能量代替裙梁端部形成塑性铰,其耗能能力和变形能力均明显优于SFT结构。大震作用下,裙梁中设置的耗能梁段充分进入塑性耗散地震能量,可以有效地减小结构的基底剪力和层间侧移角,从而降低结构的地震作用,减轻主体构件的损伤程度。SFT-RLB的残余层间侧移角小于试验测得的可允许更换残余侧移角,证明结构具有震后功能可恢复潜力。算例SFT-RLB的修正倒塌储备系数ACMR远大于允许值ACMR10%(βTOT),揭示了SFT-RLB结构具有足够的抗倒塌能力储备。展开更多
基金Supported by the National High Technology Research and Development Program of China(2013AA1548)
文摘In view of the low ranging efficiency of the conventional fixed frame-length algorithm in the inter-satellite link,an adaptive frame-length algorithm is proposed. The frame length is adjusted adaptively according to the results of ranging and velocity measuring to improve ranging efficiency. Buffers which enable the frame length to be selected discretely and adaptively are introduced to avoid frequent hopping of the frame-length.Frame length marker is created to automatically identify the frame-length for frame synchronization procedures in receivers. The feasibility and the validity of the proposed algorithm to improve the efficiency of ranging are verified through both theoretic analysis and simulation,and the efficiency improves up to 88% when there are five buffers. This improvement can be further enhanced by increasing the number of buffers. Proper allocation of inter-satellite buffers is required to make a balance between the ranging efficiency and the system complexity.
文摘以欧姆龙公司CP1H型号的PLC为应用背景,设计了基于Host Link FINS协议的PLC设备远程监控系统。该文提出了基于串口的远程通信方案,并且详细分析了Host Link FINS协议的结构和指令格式,用MFC实现了监控软件的设计,完成监控软件与欧姆龙PLC的数据通信功能,实现监控软件对PLC的远程监控。经过现场的测试和运行,该监控系统稳定可靠,性能较高。
文摘为了增强传统钢框筒结构(Steel framed-tubed structures,SFT)的抗震性能和震后功能可恢复能力,提出了螺栓拼接连接可更换耗能梁段-钢框筒结构(Steel framed-tubed structures with bolt-splice-connected repairable link beams,SFT-RLB)。首先给出了SFT-RLB结构构件的设计方法;然后基于OpenSEES平台提出了整体结构的弹塑性数值模型建模方法,通过子结构试验结果验证了有限元模型的准确性;继而设计了SFT和SFT-RLB结构算例,对比了2种结构的弹性和弹塑性性能;最后采用IDA方法对结构算例的抗地震倒塌能力进行评估。分析结果表明,SFT-RLB结构主要通过耗能梁段发展塑性耗散地震能量代替裙梁端部形成塑性铰,其耗能能力和变形能力均明显优于SFT结构。大震作用下,裙梁中设置的耗能梁段充分进入塑性耗散地震能量,可以有效地减小结构的基底剪力和层间侧移角,从而降低结构的地震作用,减轻主体构件的损伤程度。SFT-RLB的残余层间侧移角小于试验测得的可允许更换残余侧移角,证明结构具有震后功能可恢复潜力。算例SFT-RLB的修正倒塌储备系数ACMR远大于允许值ACMR10%(βTOT),揭示了SFT-RLB结构具有足够的抗倒塌能力储备。
