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易地扶贫搬迁脱贫人口的人力资本、生计模式与脱贫脆弱性——基于凉山彝区大型易地扶贫搬迁安置点的调研分析

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云南农业大学学报（社会科学版） 2025年第1期19卷 158-166页

作者：唐亮李雪苏艺泸州职业技术学院泸州商学院四川泸州646000 四川农业大学经济学院四川成都611130 四川省社会科学院农村发展研究所四川成都610072

基于凉山彝区大型易地扶贫搬迁安置点1034户脱贫家庭的调研数据,实证分析人力资本对脱贫脆弱性的影响及作用机制。研究发现:部分脱贫户的脱贫较为脆弱,但能够守住不发生规模性返贫的底线;人力资本对脱贫脆弱性具有显著的负向影响,引入... 详细信息

基于凉山彝区大型易地扶贫搬迁安置点1034户脱贫家庭的调研数据,实证分析人力资本对脱贫脆弱性的影响及作用机制。研究发现:部分脱贫户的脱贫较为脆弱,但能够守住不发生规模性返贫的底线;人力资本对脱贫脆弱性具有显著的负向影响,引入工具变量后其结论仍然成立,采用因变量替换法检验后其结论仍然稳健;人力资本对脱贫脆弱性的作用没有安置点类型差异,但有家庭收入差异;生计模式在人力资本对脱贫脆弱性的影响中起到中介作用。因此,建议高度重视脱贫脆弱性高风险的家庭,持续强化脱贫家庭人力资本的提升,创新推动脱贫家庭的生计模式转型。

关键词：脱贫脆弱性人力资本生计模式凉山彝区

Influence of low ambient pressure on the performance of a high-energy array surface arc plasma actuator

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Chinese Physics B 2020年第10期29卷 380-387页

作者： Bing-liang tang Shan-Guang Guo Hua liang Meng-Xiao tang Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi'an 710038China

In order to solve the problem of single arc plasma actuator's failure to suppress the boundary layer separation, the effectiveness of the array surface arc plasma actuator to enhance the excitation intensity is verified by experiment. In this study, an electrical parameter measurement system and high-speed schlieren technology were adopted to delve into the electrical, flow field, and excitation characteristics of the high-energy array surface arc plasma actuator under low ambient pressure. The high-energy array surface arc discharge released considerable heat rapidly;as a result, two characteristic structures were generated, i.e., the precursor shock wave and thermal deposition area. The duration increased with the increase in environmental pressure. The lower the pressure, the wider the thermal deposition area's influence range. The precursor shock wave exhibited a higher propagation speed at the initial phase of discharge;it tended to decay over time and finally remained at 340 m/s. The lower the environmental pressure, the higher the speed would be at the initial phase. High-energy array surface arc plasma actuator can be employed to achieve effective high-speed aircraft flow control.

关键词： low ambient pressure high-energy array surface arc plasma actuator

Toward the recognition of spacecraft feature components:A new benchmark and a new model

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Astrodynamics 2022年第3期6卷 237-248页

作者： Linwei Qiu liang tang Rui Zhong School of Astronautics Beihang UniversityBeijing 100191China Key Laboratory of Space Intelligent Control Technology Beijing Institute of Control EngineeringBeijing 100094China

Countries are increasingly interested in spacecraft surveillance and recognition which play an important role in on-orbit maintenance,space docking,and other *** detection methods,including radar,have many restrictions,such as excessive costs and energy supply *** many on-orbit servicing spacecraft,image recognition is a simple but relatively accurate method for obtaining sufficient position and direction information to offer ***,to the best of our knowledge,few practical machine-learning models focusing on the recognition of spacecraft feature components have been *** addition,it is difficult to find substantial on-orbit images with which to train or evaluate such a *** this study,we first created a new dataset containing numerous artificial images of on-orbit spacecraft with labeled *** base images were derived from 3D Max and STK *** images include many types of satellites and satellite *** real-world illumination conditions and imperfect camera observations,we developed a degradation algorithm that enabled us to produce thousands of artificial images of *** feature components of the spacecraft in all images were labeled *** discovered that direct utilization of the DeepLab V3+model leads to poor edge *** defined edges provide imprecise position or direction information and degrade the performance of on-orbit ***,the edge information of the target was taken as a supervisory guide,and was used to develop the proposed Edge Auxiliary Supervision DeepLab Network(EASDN).The main idea of EASDN is to provide a new edge auxiliary loss by calculating the L2 loss between the predicted edge masks and ground-truth edge masks during *** extensive experiments demonstrate that our network can perform well both on our benchmark and on real on-orbit spacecraft images from the ***,the device usage and processing time m

关键词： spacecraft deep learning feature components semantic segmentation

The boundary conditions for simulations of a shake-table experiment on the seismic response of 3D slope

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Earthquake Engineering and Engineering Vibration 2017年第1期16卷 23-32页

作者： tang liang Cong Shengyi Ling Xianzhang Ju Nengpan School of Civil Engineering Harbin Institute of Technology State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology School of Civil Engineering Qingdao Technological University

Boundary conditions can significantly affect a slope＇s behavior under strong earthquakes. To evaluate the importance of boundary conditions for finite element （FE） simulations of a shake-table experiment on the slope response, a validated three-dimensional （3D） nonlinear FE model is presented, and the numerical and experimental results are compared. For that purpose, the robust graphical user-interface ＂SlopeSAR＂, based on the open-source computational platform OpenSees, is employed, which simplifies the effort-intensive pre- and post-processing phases. The mesh resolution effect is also addressed. A parametric study is performed to evaluate the influence of boundary conditions on the FE model involving the boundary extent and three types of boundary conditions at the end faces. Generally, variations in the boundary extent produce inconsistent slope deformations. For the two end faces, fixing the y-direction displacement is not appropriate to simulate the shake-table experiment, in which the end walls are rigid and rough. In addition, the influence of the length of the 3D slope＇s top face and the width of the slope play an important role in the difference between two types of boundary conditions at the end faces （fixing the y-direction displacement and fixing the （y, z） direction displacement）. Overall, this study highlights that the assessment of a comparison between a simulation and an experimental result should be performed with due consideration to the effect of the boundary conditions.

关键词： boundary condition dynamic response soil slope nonlinear finite element analysis shake-table experimentearthquake

Effect of Cr on Microstructure and Fracture Toughness of Nb-20Ti-16Si-xCr Alloys

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稀有金属材料与工程 2009年第A3期38卷 8-12页

作者： tang liang Ma Chaoli Zhao Xinqing Beijing University of Aeronautics and Astronautics Beijing 100083 China

The present paper reported the phase stability and microstructures evolution of Nb-20Ti-16Si-xCr (x = 0～20at.%) in-situ composites as function of Cr addition. It was suggested that with the addition of Cr less than 7%, the silicide phase in as-cast Nb-20Ti-16Si alloy was Nb3Si. The silicides changed to be α-Nb5Si3 by the addition of Cr above 7%. It was found that annealing of 1300 ℃ for 100 h could result in the decomposition of Nb3Si to NbSS and α-Nb5Si3 in Cr containing Nb-20Ti-16Si based alloys by means of eutectoid reaction. Whereas in the case of alloy without Cr addition, the Nb3Si in Nb-20Ti-16Si alloy keep good stability during the high temperature annealing. The Cr additions larger than 5% in Nb-20Ti-16Si-xCr alloys could result in the formation of Cr-rich Laves phase. In addition, the influence of Cr addition on the room temperature fracture toughness of the alloys after annealing was reported.

关键词：微观结构铌硅化物韧性合金

Numerical simulations of shake-table experiment for dynamic soil-pile-structure interaction in liquefi able soils

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Earthquake Engineering and Engineering Vibration 2014年第1期13卷 171-180页

作者： tang liang Baydaa Hussain Maula Ling Xianzhang Su Lei Key Lab of Structures Dynamic Behavior and Control(Harbin Institute of Technology) Ministry of Education School of Civil Engineering Harbin Institute of Technology

A shake-table experiment on pile foundations in liquefi able soils composed of liquefi able sand and overlying soft clay is studied. A three-dimensional(3D) effective stress fi nite element(FE) analysis is employed to simulate the experiment. A recently developed multi-surface elasto-plastic constitutive model and a fully coupled dynamic inelastic FE formulation(u-p) are used to model the liquefaction behavior of the sand. The soil domains are discretized using a solid-fl uid fully coupled(u-p) 20-8 noded brick element. The pile is simulated using beam-column elements. Upon careful calibration, very good agreement is obtained between the computed and the measured dynamic behavior of the ground and the pile. A parametric analysis is also conducted on the model to investigate the effect of pile-pinning, pile diameter, pile stiffness, ground inclination angle, superstructure mass and pile head restraints on the ground improvement. It is found that the pile foundation has a noticeable pinning effect that reduces the lateral soil displacement. It is observed that a larger pile diameter and fi xed pile head restraints contribute to decreasing the lateral pile deformation; however, a higher ground inclination angle tends to increase the lateral pile head displacements and pile stiffness, and superstructure mass seems to effectively infl uence the lateral pile displacements.

关键词： liquefaction pile pinning soil improvement pile deformation earthquake nonlinear fi nite element method shake-table experiment

Deviation correction strategy for the earth pressure balance shield based on shield–soil interactions

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Frontiers of Mechanical Engineering 2022年第2期17卷 225-239页

作者： liang tang Xiangxun KONG Xianzhang LING Yize ZHAO Wenchong tang Yifan ZHANG School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China Heilongjiang Research Center for Rail Transit Engineering in Cold Regions Harbin 150090China Chongqing Research Institute Harbin Institute of TechnologyChongqing 401135China Department of Computer Science University of CaliforniaIrvineCA 92612USA

The control system presently used in shield posture rectification is based on driver experience,which is marginally *** study of the related theory is ***,a decision-making approach for the deviation correction trajectory and posture rectification load for an earth pressure balance(EPB)shield is proposed.A calculation model of posture rectification load of an EPB shield is developed by considering the interactions among the cutter head,shield shell,and *** additional position change during the shield attitude correction is *** posture rectification loads and shield behaviors results can be solved by the proposed *** influences of the stratum distribution(i.e.,bedrock height in the upper-soft and lower-hard strata)on shield behaviors and posture rectification loads are *** indicated that the increase of pitch angle in the upper-soft and lower-hard strata causes a sharp rise in vertical *** bedrock height increases the magnitudes of the required posture rectification moments when hr/D>*** a tunnel with hr/D≤0.5,the variation of hr/D has little effect on the posture rectification ***,the posture rectifying curves based on the theoretical model are compared with the target ones based on the double circular arc interpolation *** required results can be obtained regardless of the soil–rock compound stratum *** maximum rectification moment in the rock layer is almost 12.6 times that in the soil ***,this study provides a valuable reference for moment determination and the trajectory prediction of posture rectification in compound strata.

关键词： additional position change deviation correction trajectory earth pressure balance shield mechanical model posture rectification

Advances and prospects of super rice breeding in China

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Journal of Integrative Agriculture 2017年第5期16卷 984-991页

作者： tang liang XU Zheng-jin CHEN Wen-fu Rice Research Institute Shenyang Agricultural University/Key Laboratory of Northeast Rice Biology and BreedingMinistry of Agriculture/Key Laboratory of Northern japonica Super Rice BreedingMinistry of EducationShenyang 110866P.R.China

Super rice breeding in China has been very successful over the past 3 decades, and the Chinese government has made great efforts to support breeding and cultivation of both conventional and hybrid super rice. In this review, we focus on the progress in and potential of super rice breeding. After the establishment of the breeding theory and strategy of ＂generating an ideotype with strong heterosis through inter-subspecies hybridization, by using gene pyramiding to combine elite traits through composite-crossing to breed super rice varieties with both ideotype and strong hybrid vigor＂, a series of major breakthroughs have been achieved in both conventional and super hybrid rice breeding. A number of new genetic materials with ideotype have been created successfully, and the Ministry of Agriculture of China has approved 156 novel super rice varieties and combinations for commercialization. During the Developing the Super Rice Varieties Program, great attention has also been paid to the integration and demonstration of the rice production technology. Collaboration between industry and university researchers has led to technological innovations and initiation of a demonstration system for super hybrid rice. With widespread cultivation of super rice with higher quality and yield, as well as resistance or tolerance to abiotic or biotic stresses, the yield of rice production per unit has reached a new level. In addition to increased quality and yield, hybrid rice breeding has also led to improvements in many other agronomic traits, such as resistance to pests and diseases, resistance to lodging, and optimized light distribution in population. Achievements in super rice breeding and innovation in rice production have made major contributions to the progress in rice sciences and worldwide food security.

关键词： super rice super hybrid rice ideotype heterosis breeding

Nowhere-zero 15-Flow in 3-Edge-connected Bidirected Graphs

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Acta Mathematica Sinica,English Series 2014年第4期30卷 649-660页

作者： Er Ling WEI Wen liang tang Dong YE Department of Mathematics Renmin University of China Department of Mathematics West Virginia University Department of Mathematical Sciences Middle Tennessee State University

It was conjectured by Bouchet that every bidirected graph which admits a nowhere-zero κ flow will admit a nowhere-zero 6-flow. He proved that the conjecture is true when 6 is replaced by 216. Zyka improved the result with 6 replaced by 30. Xu and Zhang showed that the conjecture is true for 6-edge-connected graphs. And for 4-edge-connected graphs, Raspaud and Zhu proved it is true with 6 replaced by 4. In this paper, we show that Bouchet＇s conjecture is true with 6 replaced by 15 for 3-edge-connected graphs.

关键词： Bidirected graph integer flow signed graph