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The Impact of Climate Warming on Permafrost and Qinghai-Tibet Railway

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工程科学（英文版） 2006年第2期4卷 92-97页

作者： Wu Qingbai li Shuxun liu yongzhi State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000

Global warming is an inarguable fact. Permafrost is experiencing a change due to climate warming in Qinghai-Tibet Plateau, such as the decreasing of permafrost table, the rising of permafrost temperature, etc. On the basis of analysing the permafrost change under the climate change and engineering action, the thermal regime and spatial distribution of permafrost are predicted for air temperature rising 1℃ and 2.6℃ after 50 years in this paper. The results show that climate change results in the larger change for the thermal regime and spatial distribution of permafrost. Permafrost change will produce the great effect on the Qinghai-Tibet Railway engineering, not only resulting in the decreasing of permafrost table beneath the roadbed, but also resulting in thawing settlement due to the thawing of ground ice near permafrost table. The idea of cooling roadbed and actively protecting permafrost for the Qinghai-Tibet Railway engineering could adjust and control the permafrost thermal state, some better methods are provided to ensure the engineering stability in the areas of warm permafrost and high ice content.

关键词：青藏铁路永久冻结带气候变暖气候变化

维普期刊数据库

First detection of cutavirus DNA in stools of patients with rheumatic diseases in Guangzhou,China

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Virologica Sinica 2023年第6期38卷 860-867页

作者： yongzhi li liting Zheng Huan He Husheng Xiong Jiaqi Chen Hengbiao Sun Caiyun Chen Qiushuang li Jiaqi Fu Fei Wu Yuhan Gao Juxian Xian Minyi liang Gang Xiao Qing Chen Guangdong Provincial Key Laboratory of Tropical Disease Research Department of EpidemiologySchool of Public HealthSouthern Medical UniversityGuangzhou510515China Clinical Laboratory of Third Affiliated Hospital of Southern Medical University Guangzhou510500China

Cutavirus(CuV)is a novel protoparvovirus possibly associated with diarrhea and cutaneous T-cell *** with rheumatic disease are immunosuppressed and may be more vulnerable to pathogenic viruses.A descriptive study was conducted among hospitalized patients with rheumatic diseases and individuals undergoing medical health check-ups between June 2019 and June 2022 in Guangzhou,*** samples of subjects were tested for CuV *** and fecal examination data of patients were obtained from electronic medical records.A total of 505 patients with rheumatic diseases and 244 individuals who underwent medical health check-ups were included in the *** the patients with rheumatic disease,5.74%[95%confidence interval(CI):4.03%–8.12%]were positive for CuV DNA,while no individual in the medical health check-up group was positive,indicating a close correlation between CuV and rheumatic *** and patients with rheumatoid arthritis or ankylosing spondylitis,according to the disease classification,were more susceptible to being infected with CuV(P<0.01).After adjustments,being male remained the only significant factor,with an adjusted odd ratio(OR)of 4.4(95%CI:1.7–11.4,P=0.002).Phylogenetic analysis of the CuV VP2 sequences showed three diverse clades,one of which was segregated to be a single branching independent of previously known sequences,which is possible a new genotype.

关键词： Cutavirus(CuV) Rheumatic diseases Prevalence Risk factor Genetic characterization

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航天员长期航天飞行后疗养与康复研究进展

中华航空航天医学杂志 2024年第2期35卷 156-160页

作者：储昭亮董玲邢文娟李勇枝顾建文高峰空军军医大学航空航天医学系航空航天医学教育部重点实验室西安710032 空军军医大学第二附属医院超声诊断科西安710038 中国航天员科研训练中心航天员健康中心重点实验室北京100094 战略支援部队特色医学中心神经外科北京100101

目的综述航天员航天飞行后疗养与康复方案及其研究进展。资料来源与选择国内外发表的航天员飞行后康复疗养相关文献。资料引用引用文献资料29篇。资料综合长期处于航天环境导致航天员机体多系统发生适应性改变,对航天员身体健康和工作... 详细信息

目的综述航天员航天飞行后疗养与康复方案及其研究进展。资料来源与选择国内外发表的航天员飞行后康复疗养相关文献。资料引用引用文献资料29篇。资料综合长期处于航天环境导致航天员机体多系统发生适应性改变,对航天员身体健康和工作效能造成不利影响。航天飞行后康复疗养是保障航天员健康的重要措施。通过物理治疗和运动锻炼等手段,结合自然疗养因子,采取分阶段实施方案,可帮助航天员尽快重新适应重力环境,恢复机体功能及良好身心状态,为下一次飞行任务做好准备。结论通过制定个体化运动处方有效提升航天飞行后康复效果,以及规划合理评价指标是亟需解决的问题。

关键词：失重康复运动长期航天飞行航天员

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Research on a High-Efficiency LED Driving Circuit Based on Buck Topology

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Circuits and Systems 2011年第4期2卷 352-357页

作者： Renbo Xu Hongjian li yongzhi li Xiaomao Hou 不详

A high efficiency LED(light Emitting Diode) driver based on Buck converter, which could operate under a wide AC input voltage range(85V^265V) and drive a series of high power LEDs, is presented in this paper. The operation principles, power loss factors of the LED driver in this study are analyzed and discussed in detail and some effective ways to improve efficiency are proposed through system design considerations. To verify the feasibility, a laboratory prototype is also designed and tested for an LED lamp which consists of 16 LUMILEDS LEDs in series. Experimental results show that a high efficiency of 92% at I0=350mA can be achieved and the studied driver might be practical for driving high power LEDs. In the last, the overall efficiency over 90% is gained through some experiments under variable input and output voltages and verifies the validity of the designed driver.

关键词： LED Driver Buck Type High Efficiency Universal Input Voltage

An Improved Non-isolated LED Converter with Power Factor Correction and Average Current Mode Control

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Circuits and Systems 2011年第3期2卷 242-248页

作者： Renbo Xu Hongjian li yongzhi li Changqian Zhang 不详

A new type of high power LED drivers is proposed by adopting an improved two-stages non-isolated configuration. In order to improve power factor and achieve accurate average current control under universal input voltages ranging from 100 Vrms to 240 Vrms, the power factor correction and average current mode control methods operating in continuous current conduction mode are designed and implemented. With the LUMILEDS emitter type LEDs, a laboratory prototype is built and measured. And from the measured results, it could be concluded that the proposed driver has many better performances such as high power factor, low current harmonic, accurate average current control and switch protection.

关键词： High Power LED Power Factor Correction Average Current Mode Control

Research of an Efficient LED lighting Driver Based on Boost-Buck Converter

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Circuits and Systems 2014年第6期5卷 153-159页

作者： Renbo Xu yongzhi li lixin Zhong Jiaming liu Changsha Reform School Changsha China Department of Electronics Hunan Information Institute Changsha China Hunan Electric Power Transmission and Substation Reconnaissance and Design Consulting Co. LTD. Changsha China The First Middle School in Taoyuan Changde China

Boost-Buck converter is widely used in LED lighting drivers. In this paper, Boost-Buck main circuit related characteristics are firstly discussed, and then a new Boost-Buck high power efficient double loop control strategy is built by adopting error amplifier and integrator control method. It is demonstrated that the new system has many advantages such as high efficiency, fast response, strong anti-interference, good stability after analyses and simulations of its working dynamic characteristics.

关键词： LED lighting Boost-Buck Double Loop Control Efficient and Stable

A method for detecting two-dimensional plane stress distribution in basin-type insulator based on critically refracted longitudinal wave

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High Voltage 2024年第1期9卷 105-116页

作者： Zhaoyang Kang Fuqiang Ren Hongru Zhang Jingjing Yang Kaining Hou Qingquan li Dongxin He Hongshun liu yongzhi Zhao Huaxin Wen Shandong Provincial Key Laboratory of UHV Transmission Technology and Equipment School of Electrical EngineeringShandong UniversityJinanChina Shandong Electrical Engineering&Equipment Group Co.Ltd JinanChina SDEE Hitachi High-voltage Switchgear Co. LtdJinanChina

Basin-type insulator often has small cracks due to stress *** current method cannot accurately reflect the stress condition of the insulator to find the stress concentration *** solve these problems,a method for detecting two-dimensional plane stress(δ_(1) andδ_(2))within different depth ranges in a basin-type insulator is proposed based on critically refracted longitudinal(LCR)***,the acoustoelastic equation characterising the relationship between the variation of LCR wave propagation time and the plane stress was ***,the propagation characteristics of LCR wave in epoxy resin samples were ***,the stress distribution within different depth ranges of the insulator subjected to hydraulic load was measured using the proposed method,including direction(θ),δ_(1) andδ_(2).The results show that the magnitude of the stress alone cannot accurately characterise the stress *** with equal distances to the centre have similar stress magnitudes,but their directions are not the *** increasing depth,θremains essentially unchanged at the same location,whileδ1 andδ2 decrease,and the rate of decrease varies at different *** the measured and simulated data,the results showed that they were in good agreement,and the maximum errors of stress value andθwere 0.69 MPa and 2.97°,respectively,which confirmed the feasibility and accuracy of the stress detection in the proposed method.

关键词： stress insulator wave

Multi-objective Task Scheduling Optimization in Cloud Computing based on Genetic Algorithm and Differential Evolution Algorithm

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Multi-objective Task Scheduling Optimization in Cloud Comput...

Inhibition of Monosodium Urate Monohydrate-mediated Hemolysis by Vitamin E

第37届中国控制会议

作者： Yuqing li Shichuan Wang Xin Hong yongzhi li School of Automation China University of Geosciences

Reasonable task scheduling is a long-standing challenge in cloud computing. Scheduling process of cloud computing has the characteristics of dynamic nature, meanwhile the constraint of the target function from a single aspect cannot meet the needs of users. According to the above problem, a multi-objective task scheduling GA-DE algorithm based on Genetic Algorithm（GA） and Differential Evolution（DE） is proposed in this paper, in which total time, cost and virtual machine load balancing three aspects are taken into account simultaneously. In the phase of population initialization and crossover, diversity of the initial population is increased by introducing individual different factors, which can prevent cross-operation of similar individuals and satisfy laws of inbreeding of natural relatives. The introduction of the DE in the GA mutation stage can not only give full play to the advantages of the global search ability of GA but also accelerate the algorithm produce optimal solution by utilizing advantage of local search ability and fast convergence speed of DE. The algorithm proposed in this paper is compared with GA and DE by cloud computing simulation experiments on Cloud Sim platform. Experimental result shows that this algorithm can optimize both GA and DE in terms of quality of service and virtual machine load balancing under the same conditions, which is proved to be an efficient task scheduling algorithm in cloud computing environment.

关键词： cloud computing task scheduling multi-objective Genetic Algorithm Differential Evolution Algorithm

来源： cnki会议评论

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Acta Biochimica et Biophysica Sinica 2007年第4期39卷 273-277页

作者： Qiong XIE1# Shude li~2# Welyang FENG~2 yongzhi li~1 Yuanliang WU~1 Wei HU~1 Youguang HUANG~2* 1 Institate of Space Medico-Engineering,Beijing 100094,China 2 Department of Biochemistry Kunming Medical College,Kunming 650031,China Institute of Space Medico-EngineeringBeijing 100094 China Department of Biochemistry Kunming Medical CollegeKunming 650031 China

Microcrystals of monosodium urate monohydrate(MSUM)induce cytolysis and hemolysis *** this report,we studied the effect of vitamin E on MSUM-mediated hemolysis in *** E significantly inhibited hemolysis induced by *** hydroxyl group in thechromanol ring of vitamin E is dispensable for protecting erythrocytes against hemolysis induced by MSUM,indicating that the inhibitory effect of vitamin E is not due to its antioxidant ***,both thechromanol ring and the isoprenoid side chain are important for vitamin E to suppress MSUM-induced *** current study suggests that vitamin E inhibits hemolysis induced by MSUM as a membrane stabilizer.

关键词： monosodium urate monohydrate erythrocyte hemolysis vitamin E membrane stabilizer