This study aims to analyze seismic damage of reinforced outlet piers of arch dams by the nonlinear finite element （FE） sub-model method. First, the dam-foundation system is modeled and analyzed, in which the effects...This study aims to analyze seismic damage of reinforced outlet piers of arch dams by the nonlinear finite element （FE） sub-model method. First, the dam-foundation system is modeled and analyzed, in which the effects of infinite foundation, contraction joints, and nonlinear concrete are taken into account. The detailed structures of the outlet pier are then simulated with a refined FE model in the sub-model analysis. In this way the damage mechanism of the plain （unreinforced） outlet pier is analyzed, and the effects of two reinforcement measures （i.e., post-tensioned anchor cables and reinforcing bar） on the dynamic damage to the outlet pier are investigated comprehensively. Results show that the plain pier is damaged severely by strong earthquakes while implementation of post-tensioned anchor cables strengthens the pier effectively. In addition, radiation damping strongly alleviates seismic damage to the piers.展开更多
脉冲噪声是影响电力线通信性能的最主要因素。为了提升极化码在电力线信道的性能,文章提出了分段循环冗余校验码辅助串行抵消列表比特翻转(segmented CRC aid SCL-bit flip,SCA-SCL-BF)译码算法,并在加性高斯白噪声(additive white gaus...脉冲噪声是影响电力线通信性能的最主要因素。为了提升极化码在电力线信道的性能,文章提出了分段循环冗余校验码辅助串行抵消列表比特翻转(segmented CRC aid SCL-bit flip,SCA-SCL-BF)译码算法,并在加性高斯白噪声(additive white gaussian noise,AWGN)信道和电力线信道下进行了仿真。在构造关键集合时引入Rate1子块,避免了全集搜索的复杂度;根据关键集合中比特的位置进行分段,每段翻转一比特,可以实现多比特翻转。仿真结果表明,SCA-SCL-BF算法的性能相较于公开文献中性能在信噪比(signal-to-noiseratios,SNR)大于0dB时有显著提升。该算法对于提升电力线传输性能有重要意义。展开更多
In 1995, the Intergovernmental Panel on Climate Change (IPCC) released a thermodynamic model based on the Greenhouse Effect, aiming to forecast global temperatures. This study delves into the intricacies of that model...In 1995, the Intergovernmental Panel on Climate Change (IPCC) released a thermodynamic model based on the Greenhouse Effect, aiming to forecast global temperatures. This study delves into the intricacies of that model. Some interesting observations are revealed. The IPCC model equated average temperatures with average energy fluxes, which can cause significant errors. The model assumed that all energy fluxes remained constant, and the Earth emitted infrared radiation as if it were a blackbody. Neither of those conditions exists. The IPCC’s definition of Climate Change only includes events caused by human actions, excluding most causes. Satellite data aimed at the tops of clouds may have inferred a high Greenhouse Gas absorption flux. The model showed more energy coming from the atmosphere than absorbed from the sun, which may have caused a violation of the First and Second Laws of Thermodynamics. There were unexpectedly large gaps in the satellite data that aligned with various absorption bands of Greenhouse Gases, possibly caused by photon scattering associated with re-emissions. Based on science, we developed a cloud-based climate model that complied with the Radiation Laws and the First and Second Laws of Thermodynamics. The Cloud Model showed that 81.3% of the outgoing reflected and infrared radiation was applicable to the clouds and water vapor. In comparison, the involvement of CO<sub>2</sub> was only 0.04%, making it too minuscule to measure reliably.展开更多
A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation...A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation of black hole interior “space-and-time-reversal”. Specifically, it is proposed that the “singularity” space of the black hole interior is time-like and the expansion time of the black hole interior is space-like. The resemblance of this new insider interpretation to our own expanding and redshifting big bang universe is compelling.展开更多
基金National Natural Science Foundation of China under Grant Nos.51179093 and 91215301Specialized Research Fund for the Doctoral Program of Higher Education under Grant No.20130002110032
文摘This study aims to analyze seismic damage of reinforced outlet piers of arch dams by the nonlinear finite element （FE） sub-model method. First, the dam-foundation system is modeled and analyzed, in which the effects of infinite foundation, contraction joints, and nonlinear concrete are taken into account. The detailed structures of the outlet pier are then simulated with a refined FE model in the sub-model analysis. In this way the damage mechanism of the plain （unreinforced） outlet pier is analyzed, and the effects of two reinforcement measures （i.e., post-tensioned anchor cables and reinforcing bar） on the dynamic damage to the outlet pier are investigated comprehensively. Results show that the plain pier is damaged severely by strong earthquakes while implementation of post-tensioned anchor cables strengthens the pier effectively. In addition, radiation damping strongly alleviates seismic damage to the piers.
文摘脉冲噪声是影响电力线通信性能的最主要因素。为了提升极化码在电力线信道的性能,文章提出了分段循环冗余校验码辅助串行抵消列表比特翻转(segmented CRC aid SCL-bit flip,SCA-SCL-BF)译码算法,并在加性高斯白噪声(additive white gaussian noise,AWGN)信道和电力线信道下进行了仿真。在构造关键集合时引入Rate1子块,避免了全集搜索的复杂度;根据关键集合中比特的位置进行分段,每段翻转一比特,可以实现多比特翻转。仿真结果表明,SCA-SCL-BF算法的性能相较于公开文献中性能在信噪比(signal-to-noiseratios,SNR)大于0dB时有显著提升。该算法对于提升电力线传输性能有重要意义。
文摘In 1995, the Intergovernmental Panel on Climate Change (IPCC) released a thermodynamic model based on the Greenhouse Effect, aiming to forecast global temperatures. This study delves into the intricacies of that model. Some interesting observations are revealed. The IPCC model equated average temperatures with average energy fluxes, which can cause significant errors. The model assumed that all energy fluxes remained constant, and the Earth emitted infrared radiation as if it were a blackbody. Neither of those conditions exists. The IPCC’s definition of Climate Change only includes events caused by human actions, excluding most causes. Satellite data aimed at the tops of clouds may have inferred a high Greenhouse Gas absorption flux. The model showed more energy coming from the atmosphere than absorbed from the sun, which may have caused a violation of the First and Second Laws of Thermodynamics. There were unexpectedly large gaps in the satellite data that aligned with various absorption bands of Greenhouse Gases, possibly caused by photon scattering associated with re-emissions. Based on science, we developed a cloud-based climate model that complied with the Radiation Laws and the First and Second Laws of Thermodynamics. The Cloud Model showed that 81.3% of the outgoing reflected and infrared radiation was applicable to the clouds and water vapor. In comparison, the involvement of CO<sub>2</sub> was only 0.04%, making it too minuscule to measure reliably.
文摘A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation of black hole interior “space-and-time-reversal”. Specifically, it is proposed that the “singularity” space of the black hole interior is time-like and the expansion time of the black hole interior is space-like. The resemblance of this new insider interpretation to our own expanding and redshifting big bang universe is compelling.
