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北京体育大学学报 2000年第1期23卷 39-40页

作者：宋信勇山东体育学院武术系山东济南250063

排球运动员发球时的心理定向不仅影响发球的落点、球性 ,而且影响发球攻击性大小。影响运动员发球心理定向的因素包括比赛的性质、临场赛况 ;

关键词：心理定向运动焦虑排球运动员发球效能

Influence of Sub-Cloud Secondary Evaporation Effects on the Stable Isotopes in Precipitation of Urumqi Glacier No.1,Eastern Tianshan

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Journal of Earth Science 2024年第1期35卷 177-189页

作者： Mengyuan song Zhongqin Li Feiteng Wang xin Zhang State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesTianshan Glaciological StationChinese Academy of SciencesLanzhou 730000China College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730000China College of Sciences Shihezi UniversityShihezi 832000China

In arid regions,the stable hydrogen and oxygen isotopic composition in raindrops is often modified by sub-cloud secondary evaporation when they descend from cloud base to ground through the unsaturated *** a result of kinetic fractionation,the slope and intercept of the δ^(2)H-δ^(18)O correlation equation *** variation of deuterium excess from cloud base to the ground is often used to quantitatively evaluate the influence of secondary evaporation effect on isotopes in *** on the event-based precipitation samples collected at Urumqi Glacier No.1,eastern Tianshan during four-year observation,the existence and impact of secondary evaporation effects were analyzed by the methods of isotope-evaporation *** high air temperature,small raindrop diameter and precipitation amount,and low relative humidity conditions,the remaining rate of raindrops is small and the change of deuterium excess is large relatively,and the slope and intercept of δ^(2)H-δ^(18)O correlation equation are much lower than those of Global Meteoric Water Line,which mean that the influence secondary evaporation on precipitation *** on the conditions of low air temperature,high relative humidity,heavy rainfall,and large raindrop diameter,the change of deuterium excess is small relatively and the remaining rate of raindrops is large,and the slope and intercept of δ^(2)H-δ^(18)O correlation equation increase,the secondary evaporation is *** isotope-evaporation model described a good linear correlation between changes of deuterium excess and evaporation proportion with the slope of 0.90‰/%,which indicated that an increase of 1%in evaporation may result in a decrease of deuterium excess about 0.90‰.

关键词： stable isotopes meteoric water line deuterium excess sub-cloud secondary evaporation effect precipitation glaciers

Fine-grained grid computing model for Wi-Fi indoor localization in complex environments

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Journal of Electronic Science and Technology 2024年第1期22卷 42-52页

作者： Yan Liang song Chen xin Dong Tu Liu School of Computer Engineering Chengdu Technological UniversityChengdu611730China HAN Networks Corporation Limited Beijing100094China

The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor ***,the construction of the fingerprint database is quite *** when the position of the access point(AP)or wall changes,updating the fingerprint database in real-time is *** appropriate indoor localization approach,which has a low implementation cost,excellent real-time performance,and high localization accuracy and fully considers complex indoor environment factors,is preferred in location-based services(LBSs)*** this paper,we proposed a fine-grained grid computing(FGGC)model to achieve decimeter-level localization *** points(RPs)are generated in the grid by the FGGC ***,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dimensional propagation distance,and walls in complex *** a result,the fingerprint database can be established automatically without manual measurement,and the efficiency and cost that the FGGC model takes for the fingerprint database are superior to previous *** proposed indoor localization approach,which estimates the position step by step from the approximate grid location to the fine-grained location,can achieve higher real-time performance and localization accuracy *** mean error of the proposed model is 0.36 m,far lower than that of previous ***,the proposed model is feasible to improve the efficiency and accuracy of Wi-Fi indoor *** also shows high-accuracy performance with a fast running speed even under a large-size *** results indicate that the proposed method can also be suitable for precise marketing,indoor navigation,and emergency rescue.

关键词： Fine-grained grid computing (FGGC) Indoor localization Path loss Random forest Reference points(RPs)

The Extension Dimension of Subcategories and Recollements of Abelian Categories

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1042-1058页

作者： xin MA Ye Yang PENG Zhao yong HUANG College of Science Henan University of EngineeringZhengzhou 451191P.R.China Department of Mathematics Nanjing UniversityNanjing 210093P.R.China

We investigate the behavior of the extension dimension of subcategories of abelian categories under ***Λ',Λ,Λ"be art in algebras such that(modΛ',mod A,modΛ")is a recollement,and let D'and D"be subcategories of modΛand modΛ"*** any n,m≥0,under some conditions,we get dimΩ^(k)(D)≤dimΩ^(n)(D')+dimΩ^(m)(D")+1,where k=max{m,n}and D is the subcategory of modΛglued by D'and D";moreover,we give a sufficient condition such that the converse inequality holds *** applications,some results for Igusa-Todorov subcategories and syzygy finite sub categories are obtained.

关键词： Recollements extension dimension Igusa–Todorov subcategories syzygy finite subcategories

Comparative Study on the Immunogenicity and Efficacy of Different Post-exposure Intramuscular Rabies Vaccination Regimens in China

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Biomedical and Environmental Sciences 2024年第2期37卷 178-186页

作者： song Yun HE Ying LU Xue xin ZHANG Xiao Mei JIANG XIAO Lin song Qing HUANG Xue yong MA Hong Xia YU Peng Cheng ZHU Wu Yang Henan Provincial Center for Disease Control and Prevention Infectious Disease Prevention and Control InstituteHenan Provincial Key Laboratory of Infectious Disease PathogensZhengzhou 450000HenanChina National Institute for Viral Disease Control and Prevention China CDCKey Laboratory of BiosafetyNational Health CommissionBeijing 102206China Shandong Provincial Center for Disease Control and Prevention Jinan 250014ShandongChina Qingdao Chengyang District Center for Disease Control and Prevention Qingdao 266108ShandongChina

Objective This study aimed to compare the current Essen rabies post-exposure immunization schedule(0-3-7-14-28)in China and the simple 4-dose schedule(0-3-7-14)newly recommended by the World Health Organization in terms of their safety,efficacy,and *** Mice were vaccinated according to different immunization schedules,and blood was collected for detection of rabies virus neutralizing antibodies(RVNAs)on days 14,21,28,35,and 120after the first ***,different groups of mice were injected with lethal doses of the CVS-11 virus on day 0,subjected to different rabies immunization schedules,and assessed for morbidity and death *** a clinical trial,185 rabies-exposed individuals were selected for post-exposure vaccination according to the Essen schedule,and blood was collected for RVNAs detection on days 28and 42 after the first *** A statistically significant difference in RVNAs between mice in the Essen and 0-3-7-14 schedule groups was observed on the 35th day(P0.05)in RVNAs levels at any time *** post-exposure immune protective test showed that the survival rate of mice in the control group was 20%,whereas that in the immunization groups was 40%.In the clinical trial,the RVNAs positive conversion rates on days 28(14 days after 4 doses)and 42(14 days after 5 doses)were both 100%,and no significant difference in RVNAs levels was observed(P>0.05).Conclusion The simple 4-dose schedule can produce sufficient RVNAs levels,with no significant effect of a delayed fourth vaccine dose(14–28 d)on the immunization potential.

关键词： Rabies Post-exposure immunization Essen regimen RVNAs

Empirical likelihood for spatial cross-sectional data models with matrix exponential spatial specification

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 125-139页

作者： LIU Yan RONG Jian-rong QIN yong-song Nanning University Nanning 530200China Center for Applied Mathematics of Guangxi and College of Mathematics and Statistics Guangxi Normal UniversityGuilin 541004China

In this paper,we study spatial cross-sectional data models in the form of matrix exponential spatial specification(MESS),where MESS appears in both dependent and error *** empirical likelihood(EL)ratio statistics are established for the parameters of the MESS *** is shown that the limiting distributions of EL ratio statistics follow chi-square distributions,which are used to construct the confidence regions of model *** experiments are conducted to compare the performances of confidence regions based on EL method and normal approximation method.

关键词： MESS empirical likelihood con dence region

Winter extreme precipitation over the Tibetan Plateau influenced by Arctic sea ice on interdecadal timescale

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Advances in Climate Change Research 2024年第1期15卷 42-51页

作者： Qing-Quan LI Miao BI song YANG Qing-Yuan WU Yi-Hui DING xin-yong SHEN Xiao-Ting SUN Meng-Chu ZHAO China Meteorological Administration Key Laboratory for Climate Prediction Studies National Climate CentreBeijing 100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China CMA Key Open Laboratory of Transforming Climate Resources to Economy Chongqing Institute of Meteorological SciencesChongqing 401147China School of Atmospheric Sciences and Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies Sun Yat-sen University Zhuhai 519082China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China

The Tibetan Plateau(TP)and the Arctic are the most sensitive regions to global climate ***,the interdecadal varibility of winter extreme precipitation over the TP and its linkage with Arctic sea ice are still *** this study,the characteristics and mechisnems of the TP extreme precipitation(TPEP)influenced by Arctic sea ice on interdecadal timescale are studied based on the daily precipitation,monthly sea ice concentration and ERA5 reanalysis data from 1980 to *** found that the dominant mode of the TPEP in winter mostly exhibits a uniform spatial variation on the interdecadal timescale,with an opposite weak variation in the southeastern TP,and the Arctic sea ice concentration(SIC)before 2002 are larger than that after *** interdecadal variation of TPEP is affected by two teleconnection wave trains regulated by the Barents and Kara Sea *** the light ice years,a remarkable positive geopotential height(HGT)anomaly appears over the Barents-Kara Sea and a remarkable negative HGT anomaly is located over the Lake *** wave trains originating over the Barents-Kara Sea can be *** southern branch forms a wave train through the North Atlantic along the subtropical westerly jet stream,showing a‘+-+-+'pattern of HGT anomalies from Arctic to the *** HGT anomaly controls the western TP,which creates dynamic and water vapor conditions for the *** northern branch forms a wave train through the Lake Baikal and the southeast of the TP,showing a‘+-+'HGT anomaly *** HGT anomaly controls the southeastern TP,which is not conducive to precipitation in the *** the SIC in the Barents-Kara Sea increases,the situation is *** above analysis also reveals the reason for the difference in the east-west distribution of the TPEP.

关键词： Arctic sea ice Tibetan Plateau Winter extreme precipitation Rossby wave activity Interdecadal variation

Simulation study on cuttings transport of the backreaming operation for long horizontal section wells

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Petroleum Science 2024年第2期21卷 1149-1170页

作者： Yu-Fei Chen Hui Zhang Wen-xin Wu Jun Li yong Ouyang Zong-Yu Lu De-xin Ma yong-Chuan Wu Jun-Bo Liu Ke-Rou Liu Zhuo-xin Dong China University of Petroleum(Beijing) Beijing102249China Beijing Normal University at Zhuhai Experimental and Practical Education Innovation CenterZhuhai519087GuangdongChina Oil&Gas Technology Research Institute of PetroChina Changqing Oilfield Company Xi'an710016ShaanxiChina PetroChina xinjiang Oilfield Company Karamay834002XinjiangChina China Oilfield Services Ltd. Tianjin300459China

The backreaming operation plays a significant role in safe drilling for horizontal wellbores, while it may cause severe stuck pipe accidents. To lower the risk of the stuck pipe in backreaming operations, the mechanism of cuttings transport needs to be carefully investigated. In this research, a transient cuttings transport with multiple flow patterns model is developed to predict the evolution of cuttings transported in the annulus while backreaming. The established model can provide predictions of the distribution of cuttings bed along the wellbore considering the bulldozer effect caused by large-size drilling tools(LSDTs). The sensitivity analyses of the size of LSDTs, and backreaming operating parameters are conducted in Section 4. And a new theory is proposed to explain the mechanism of cuttings transport in the backreaming operation, in which both the bit and LSDTs have the “cleaning effect” and “plugging effect”.The results demonstrate that the cuttings bed in annuli is in a state of dynamic equilibrium, but the overall trend and the distribution pattern are obvious. First, larger diameters and longer drilling tools could lead to a higher risk of the stuck pipe. Second, we find that it is not the case that the higher flow rate is always better for hole cleaning, so three flow-rate intervals are discussed separately under the given conditions. When the “dangerous flow rate”(35 L/s in Case 4),the higher the flow rate, the better the cleaning effect of cuttings beds. Third, an interval of tripping velocity called “dangerous velocity” is proposed, in which the cuttings bed accumulation near the LSDTs is more serious than

关键词： Backreaming Stuck pipe Hole cleaning Transient solid transport Multiple flow patterns

补充烟酸及耐力训练对急性酒精性肝损伤大鼠SirT1活性与表达的影响及机制研究

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山东体育学院学报 2012年第6期28卷 68-72页

作者：宋信勇山东体育学院山东济南250102

目的:研究补充烟酸及耐力训练对急性酒精性肝损伤大鼠SirT1表达、活性的影响及机制。研究方法:以Wistar大鼠建立急性酒精性肝损伤模型,以跑台运动为训练手段,并且给予大鼠补充烟酸,测定血清ALT和AS以及肝脏MnSOD活性、NAD+/NADH比值、MD... 详细信息

目的:研究补充烟酸及耐力训练对急性酒精性肝损伤大鼠SirT1表达、活性的影响及机制。研究方法:以Wistar大鼠建立急性酒精性肝损伤模型,以跑台运动为训练手段,并且给予大鼠补充烟酸,测定血清ALT和AS以及肝脏MnSOD活性、NAD+/NADH比值、MDA含量、SirT1活性、线粒体ATP合成活力、MnSOD和SirT1mRNA表达。结果:急性酒精摄入导致血清ALT和AST水平、肝脏MDA含量均显著升高,线粒体ATP合成活力、肝脏NAD+/NADH比值、MnSOD及SirT1活性及mRNA表达均显著降低;耐力训练及补充烟酸再给予酒精摄入与只给予酒精摄入血清ALT和AST水平、肝脏MDA含量、线粒体ATP合成活力、肝脏NAD+/NADH比值、MnSOD及SirT1活性及mRNA表达变化规律一致,但变化幅度相对较小。结论:耐力训练及补充烟酸均能提高肝脏细胞内NAD+/NADH的比值,使SirT1活性及表达升高,进而提高肝脏细胞抗氧化能力,达到预防/改善急性酒精性肝损伤的目的。

关键词：烟酸耐力训练急性酒精性肝损伤沉默信息调节因子

青少年网球运动员一次单打比赛对血清心肌肌钙蛋白变化的影响

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山东体育科技 2013年第5期35卷 78-82页

作者：宋信勇山东体育学院运动系山东济南250102

目的:研究一次网球比赛对青少年运动员血清心肌肌钙蛋白的影响,为网球运动训练监控提供参考依据。方法:以16名青少年网球运动员为研究对象,以一次三盘制网球教学比赛为运动手段,均进行三盘比赛,在比赛前、第一盘结束即刻、第二盘结束即... 详细信息

目的:研究一次网球比赛对青少年运动员血清心肌肌钙蛋白的影响,为网球运动训练监控提供参考依据。方法:以16名青少年网球运动员为研究对象,以一次三盘制网球教学比赛为运动手段,均进行三盘比赛,在比赛前、第一盘结束即刻、第二盘结束即刻、比赛结束即刻、比赛后4小时和24小时分别取静脉血,测定血清cTnT和cTnI。结果:从第二盘比赛结束开始,血清cTnT和cTnI均开始显著升高,比赛后4小时达到峰值,24小时候cTnT恢复到正常水平,而cTnI依然显著高于正常水平,性别间无显著性差异;比赛第二盘结束即刻、比赛结束即刻、比赛结束4小时、24小时,血清cTnT和cTnI超过心肌损伤界值的人数分别为3人、8人、15人、3人和6人、10人、15人、7人,超过急性心肌损伤临界值在比赛结束和结束4小时分别为3人、11人和3人、12人。在比赛结束即刻和比赛后4小时,比赛失败运动员血清cTnT和cTnI显著高于胜利运动员,而比赛后24小时,仅cTnI显著升高。结论:一次网球比赛可以诱导青少年运动员心肌肌钙蛋白释放显著增加。

关键词：青少年网球运动员单打比赛心肌肌钙蛋白