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Prolonged penile strangulation with metal clamps 被引量:4
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作者 Chirag Patel Richard Kim Michael Delterzo 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第1期105-106,共2页
Various different objects have been reported to strangulate the penis,We reported on a patient who used metal radiator clamps for an extended period of time .Workup included history,physical examination and urinalysis... Various different objects have been reported to strangulate the penis,We reported on a patient who used metal radiator clamps for an extended period of time .Workup included history,physical examination and urinalysis.The patient was taken to the operating room for further evaluation with cystourethroscopy and orthopedic wire cutters were used to break the metal bands.(Asian J Androl 2006Jan;8:105-106) 展开更多
关键词 penis penile strangulation metal clamps
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The Rapid Development of Technology in Making Iron Clamps of Three Ancient Temples in the Archaic and Classical Period
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作者 George Varoufakis 《Journal of Chemistry and Chemical Engineering》 2012年第12期1136-1141,共6页
A few years ago, the present author had the opportunity to study the iron clamps of the archaic and classical temples. This research led to very interesting results concerning the development of technology applied in ... A few years ago, the present author had the opportunity to study the iron clamps of the archaic and classical temples. This research led to very interesting results concerning the development of technology applied in making those clamps and what is more its rapid evolution in a very short period. For instance, the technology in making the clamps of Parthenon and those of the Epikourios Apollo differs completely, although the latter was erected by the same engineer, Iktinos. Actually, it is a revolutionary one as compared with that applied in the erection of Parthenon. The paper starts by examining the making of the archaic Trapeza iron clamps and continue with those of the Parthenon and the Epikourios Apollo. 展开更多
关键词 Iron clamps archaic temples classical temples development in technology macro micro examination.
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A Comparison Study of Diode-String ESD Clamps for CMOS Input Protection
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作者 Jin Young Choi 《Circuits and Systems》 2019年第2期21-36,共16页
Based on 2-D device simulations and mixed-mode transient simulations, DC and transient discharge characteristics of a usual diode string utilizing a standard CMOS process, and a diode string utilizing a triple-well CM... Based on 2-D device simulations and mixed-mode transient simulations, DC and transient discharge characteristics of a usual diode string utilizing a standard CMOS process, and a diode string utilizing a triple-well CMOS process, which can serve as an essential VDD-VSS clamp device for CMOS input ESD protection were compared. Transient discharge characteristics including peak voltages developed across gates oxides of transistors in input buffers, lattice heating inside ESD protection devices, and ratios of discharge current components at its peak inside the diode-string clamp were compared. DC standby current levels added per each input pad structure, which are the critical parameters determining usefulness of the devices, were also compared. We showed that the diode-string devices in comparison can serve successfully as a VDD-VSS clamp device for ESD protection by virtue of the dominant pnpn thyristor-related conduction mechanisms. Optimization of design parameters including anode-cathode contact spacing in each diode in the string, device width of the diode string, and number of diodes in the diode string was performed to present transient discharge and DC characteristics of some recommendable design examples, which can serve as a guideline in designing diode-string clamp devices. 展开更多
关键词 ESD INPUT PROTECTION DIODE STRING Clamp CMOS
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Prenatal exposure to perfluorooctane sulfonate and perfluorooctanoate and the risk of preeclampsia: a nested case-control study in Shanghai, China
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作者 Ying Zhao Jizi Zhou +4 位作者 Huangfang Xu Huanqiang Zhao Ping An Xiaotian Li Yu Xiong 《Chinese Medical Journal》 SCIE CAS CSCD 2023年第7期857-859,共3页
To the Editor:Preeclampsia presents with new-onset hypertension and maternal multi-organ injury that is associated with substantial maternal and fetal morbidity and mortality.[1]Although the etiology remains a mystery... To the Editor:Preeclampsia presents with new-onset hypertension and maternal multi-organ injury that is associated with substantial maternal and fetal morbidity and mortality.[1]Although the etiology remains a mystery,environmental toxicants,especially those that interact with genetic factors and disrupt normal placental function,are emerging as potential risk factors for preeclampsia. 展开更多
关键词 MORTALITY FETAL CLAMP
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Comparison of nonlinear modeling methods for the composite rubber clamp
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作者 Yiming CAO Hui MA +4 位作者 Xumin GUO Bingfeng ZHAO Hui LI Xin WANG Bing WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第5期763-778,共16页
The cubic stiffness force model(CSFM)and Bouc-Wen model(BWM)are introduced and compared innovatively.The unknown coefficients of the nonlinear models are identified by the genetic algorithm combined with experiments.B... The cubic stiffness force model(CSFM)and Bouc-Wen model(BWM)are introduced and compared innovatively.The unknown coefficients of the nonlinear models are identified by the genetic algorithm combined with experiments.By fitting the identified nonlinear coefficients under different excitation amplitudes,the nonlinear vibration responses of the system are predicted.The results show that the accuracy of the BWM is higher than that of the CSFM,especially in the non-resonant region.However,the optimization time of the BWM is longer than that of the CSFM. 展开更多
关键词 pipeline system nonlinear clamp model composite rubber clamp amplitude-dependent characteristic vibration response experiment
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Impact of T_(i)/T_(e )ratio on ion transport based on EAST H-mode plasmas
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作者 刘建文 臧庆 +14 位作者 梁云峰 陈佳乐 邬潇河 Alexander KNIEPS 扈嘉辉 金仡飞 张斌 储宇奇 刘海庆 吕波 段艳敏 李妙辉 陈颖杰 龚先祖 the EAST Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第4期68-78,共11页
At the EAST tokamak, the ion temperature(T_(i)) is observed to be clamped around 1.25 keV in electron cyclotron resonance(ECR)-heated plasmas, even at core electron temperatures up to 10 keV(depending on the ECR heati... At the EAST tokamak, the ion temperature(T_(i)) is observed to be clamped around 1.25 keV in electron cyclotron resonance(ECR)-heated plasmas, even at core electron temperatures up to 10 keV(depending on the ECR heating power and the plasma density). This clamping results from the lack of direct ion heating and high levels of turbulence-driven transport. Turbulent transport analysis shows that trapped electron mode and electron temperature gradient-driven modes are the most unstable modes in the core of ECR-heated H-mode plasmas. Nevertheless, recently it was found that the T_(i)/T_(e)ratio can increase further with the fraction of the neutral beam injection(NBI) power, which leads to a higher core ion temperature(Ti0). In NBI heating-dominant H-mode plasmas, the ion temperature gradient-driven modes become the most unstable modes.Furthermore, a strong and broad internal transport barrier(ITB) can form at the plasma core in high-power NBI-heated H-mode plasmas when the T_(i)/T_(e)ratio approaches ~1, which results in steep core Teand Tiprofiles, as well as a peaked neprofile. Power balance analysis shows a weaker Teprofile stiffness after the formation of ITBs in the core plasma region, where Ticlamping is broken,and the core Tican increase further above 2 keV, which is 80% higher than the value of Ticlamping in ECR-heated plasmas. This finding proposes a possible solution to the problem of Ticlamping on EAST and demonstrates an advanced operational regime with the formation of a strong and broad ITB for future fusion plasmas dominated by electron heating. 展开更多
关键词 ion temperature clamping TRANSPORT neutral beam injection STIFFNESS internal transport barrier
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Effect of an Airbag-selective Portal Vein Blood Arrester on the Liver after Hepatectomy:A New Technique for Selective Clamping of the Portal Vein
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作者 Ce-xiong FU Xiao-ri QIN +6 位作者 Jin-song CHEN Jie ZHONG Yu-xu XIE Bi-dan LI Qing-qing FU Fang LI Jin-fang ZHENG 《Current Medical Science》 SCIE CAS 2024年第2期380-390,共11页
Objective:A novel technique was explored using an airbag-selective portal vein blood arrester that circumvents the need for an intraoperative assessment of anatomical variations in patients with complex intrahepatic s... Objective:A novel technique was explored using an airbag-selective portal vein blood arrester that circumvents the need for an intraoperative assessment of anatomical variations in patients with complex intrahepatic space-occupying lesions.Methods:Rabbits undergoing hepatectomy were randomly assigned to 4 groups:intermittent portal triad clamping(PTC),intermittent portal vein clamping(PVC),intermittent portal vein blocker with an airbag-selective portal vein blood arrester(APC),and without portal blood occlusion(control).Hepatic ischemia and reperfusion injury were assessed by measuring the 7-day survival rate,blood loss,liver function,hepatic pathology,hepatic inflammatory cytokine infiltration,hepatic malondialdehyde levels,and proliferating cell nuclear antigen levels.Results:Liver damage was substantially reduced in the APC and PVC groups.The APC animals exhibited transaminase levels similar to or less oxidative stress damage and inflammatory hepatocellular injury compared to those exhibited by the PVC animals.Bleeding was significantly higher in the control group than in the other groups.The APC group had less bleeding than the PVC group because of the avoidance of portal vein skeletonization during hepatectomy.Thus,more operative time was saved in the APC group than in the PVC group.Moreover,the total 7-day survival rate in the APC group was higher than that in the PTC group.Conclusion:Airbag-selective portal vein blood arresters may help protect against hepatic ischemia and reperfusion injury in rabbits undergoing partial hepatectomy.This technique may also help prevent liver damage in patients requiring hepatectomy. 展开更多
关键词 HEPATECTOMY portal vein hepatic damage selective clamping
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Major liver resections,perioperative issues and posthepatectomy liver failure:A comprehensive update for the anesthesiologist
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作者 Andrea De Gasperi Laura Petrò +11 位作者 Ombretta Amici Ilenia Scaffidi Pietro Molinari Caterina Barbaglio Eva Cibelli Beatrice Penzo Elena Roselli Andrea Brunetti Maxim Neganov Alessandro Giacomoni Paolo Aseni Elena Guffanti 《World Journal of Critical Care Medicine》 2024年第2期49-71,共23页
Significant advances in surgical techniques and relevant medium-and long-term outcomes over the past two decades have led to a substantial expansion in the indications for major liver resections.To support these outst... Significant advances in surgical techniques and relevant medium-and long-term outcomes over the past two decades have led to a substantial expansion in the indications for major liver resections.To support these outstanding results and to reduce perioperative complications,anesthesiologists must address and master key perioperative issues(preoperative assessment,proactive intraoperative anesthesia strategies,and implementation of the Enhanced Recovery After Surgery approach).Intensive care unit monitoring immediately following liver surgery remains a subject of active and often unresolved debate.Among postoperative complications,posthepatectomy liver failure(PHLF)occurs in different grades of severity(A-C)and frequency(9%-30%),and it is the main cause of 90-d postoperative mortality.PHLF,recently redefined with pragmatic clinical criteria and perioperative scores,can be predicted,prevented,or anticipated.This review highlights:(1)The systemic consequences of surgical manipulations anesthesiologistsmust respond to or prevent,to positively impact PHLF(a proactive approach);and(2)the maximal intensivetreatment of PHLF,including artificial options,mainly based,so far,on Acute Liver Failure treatment(s),to buytime waiting for the recovery of the native liver or,when appropriate and in very selected cases,toward livertransplant.Such a clinical context requires a strong commitment to surgeons,anesthesiologists,and intensivists towork together,for a fruitful collaboration in a mandatory clinical continuum. 展开更多
关键词 Liver resection Chronic liver disease Preoperative assessment Vascular clamping Intraoperative hemodynamic monitoring Postoperative intensive care unit Posthepatectomy liver failure Artificial liver support
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A dynamic modeling approach for nonlinear vibration analysis of the L-type pipeline system with clamps 被引量:12
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作者 Qingdong CHAI Jin ZENG +2 位作者 Hui MA Kun LI Qingkai HAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第12期3253-3265,共13页
There exists a lot of research on the nonlinear vibration of the pipeline system with different boundary conditions.To the best of our knowledge,little research on the actual constraint of the clamp has been performed... There exists a lot of research on the nonlinear vibration of the pipeline system with different boundary conditions.To the best of our knowledge,little research on the actual constraint of the clamp has been performed.In this paper,according to hysteresis loops of the clamp obtained from experimental test,the simplified bilinear stiffness and damping model is proposed.Then the Finite Element(FE)model of L-type pipeline system with clamps is established using Timoshenko beam theory in combination with aforementioned stiffness-damping model.Both hammering and shaker tests verify the FE model via the comparisons of natural frequencies and vibration responses.The results show that the maximum errors of natural frequencies and vibration responses are about 8.31%and 17.6%,respectively.The proposed model can simulate the dynamic characteristics of the L-type pipeline system with clamps well,which is helpful to provide some guidance for the early design stage of pipeline in aero-engine. 展开更多
关键词 CLAMP Dynamic modeling Experimental test Finite element Nonlinear vibration PIPELINE
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Pipelines vibration analysis and control based on clamps'locations optimization of multi-pump system 被引量:5
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作者 Xin LI Weihao LI +2 位作者 Jian SHI Qiang LI Shaoping WANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第6期352-366,共15页
The violent vibration of hydraulic pipelines in aircraft may cause faults or even an accident,especially for the large aircraft with the multi-pump system because of different vibration sources and complex pipelines s... The violent vibration of hydraulic pipelines in aircraft may cause faults or even an accident,especially for the large aircraft with the multi-pump system because of different vibration sources and complex pipelines system.Aiming to the vibration analysis and control of the multipump system,this paper proposed the clamps’locations optimization to minimize the system impedance at vibration frequencies.Firstly,the models of the flexible clamp and other components in multi-pump system were established,based on which,the system impedance was calculated by using Transfer Matrix Method(TMM);Secondly,the objective function is defined as weighted sum of system impedance at frequencies of different vibration sources.Then,the clamps’locations were altered to change the system impedance.Moreover,The Chaotic Swarm Particle Optimization(CPSO)algorithm was applied to obtain the optimal clamps’locations and the minimum value of objective function which decreased by 36.4%compared to the value of original clamps’locations;Finally,the experiments from vibration and pressure test with original and optimized clamps’locations verified the effectiveness of the system impedance calculation and clamps’locations optimization method. 展开更多
关键词 CLAMP CPSO Impedance Multi-pump Pipeline TMM Vibration
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CD81,a new actor in the development of preeclampsia 被引量:1
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作者 Honglei Duan Yali Hu 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2021年第8期2061-2061,共1页
CD81 is a widely expressed transmembrane protein that provides a scaffold for signaling molecules and orchestrates interactions among membrane-associated proteins to initiate signaling cascades related to cell migrati... CD81 is a widely expressed transmembrane protein that provides a scaffold for signaling molecules and orchestrates interactions among membrane-associated proteins to initiate signaling cascades related to cell migration,adhesion,and fusion1.CD81 exerts a wide range of regulatory effects on immune cells.In B cells,CD81 facilitates the assembly of CD19-CR2/CD21 and B-cell receptor complexes at tetraspanin-enriched signaling microdomains,lowering the threshold dose of antigen required to trigger B-cell clonal expansion and antibody production. 展开更多
关键词 CD81 enriched CLAMP
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Residual Capacity of Friction⁃Type High⁃Strength Bolted T⁃stub Connection with Nut Corrosion Damage
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作者 Gangnian Xu Baoyao Lin Yefeng Du 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第3期68-84,共17页
Corrosion is a primary cause of the slippage of friction⁃type high⁃strength bolted(FHSB)T⁃stub connections.This paper attempts to quantify the residual capacity of FHSB T⁃stub connections with corroded nuts.Firstly,co... Corrosion is a primary cause of the slippage of friction⁃type high⁃strength bolted(FHSB)T⁃stub connections.This paper attempts to quantify the residual capacity of FHSB T⁃stub connections with corroded nuts.Firstly,corrosion simulation tests were conducted on 48 manually cut nuts to find out the relationship between the damage degree of nut section and the residual clamping force(RCF)of bolt.Then,static load tests were carried out on 24 FHSB T⁃stub connections with nuts of different degrees of damage to obtain the failure modes.By finite⁃element(FE)models,a comparative analysis was performed on the initial friction load(IFL)and ultimate strength(US)of each connection with corroded nuts.Finally,the parameters of 96 FE models for FHSB T⁃stub connections were analyzed and used to derive the calculation formulas for the degree of damage for each nut and the IFL and US of each connection.The results show that the RCF decay of a bolt is a quadratic function of the equivalent radius loss ratio and the shear failure after nut corrosion;the IFL of each connection had a clear linear correlation with the RCF of the corresponding bolts,and the correlation depends on the applied load and static friction on connecting plate interface induced by the clamping force;the static friction had little impact on the US of the connection;the proposed IFL and US formulas can effectively derive the residual anti⁃slip capacity of FHSB T⁃stub connections from the degree of damage of the corroded nut section.The research results provide a scientific basis for the replacement and maintenance of corroded bolts of FHSB T⁃stub connections. 展开更多
关键词 nut corrosion T⁃stub connection high⁃strength bolt sectional damage residual clamping force(RCF) anti⁃slip capacity
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Improved Clamped Diode Based Z-Source Network for Three Phase Induction Motor
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作者 D.Bensiker Raja Singh R.Suja Mani Malar 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期683-702,共20页
The 3Φinduction motor is a broadly used electric machine in industrial applications,which plays a vital role in industries because of having plenty of beneficial impacts like low cost and easiness but the problems lik... The 3Φinduction motor is a broadly used electric machine in industrial applications,which plays a vital role in industries because of having plenty of beneficial impacts like low cost and easiness but the problems like decrease in motor speed due to load,high consumption of current and high ripple occurrence of ripples have reduced its preferences.The ultimate objective of this study is to control change in motor speed due to load variations.An improved Trans Z Source Inverter(ΓZSI)with a clamping diode is employed to maintain constant input voltage,reduce ripples and voltage overshoot.To operate induction motor at rated speed,different controllers are used.The conventional Proportional-Inte-gral(PI)controller suffers from high settling time and maximum peak overshoot.To overcome these limitations,Fractional Order Proportional Integral Derivative(FOPID)controller optimized by Gray Wolf Optimization(GWO)technique is employed to provide better performance by eliminating maximum peak overshoot pro-blems.The proposed speed controller provides good dynamic response and controls the induction motor more effectively.The complete setup is implemented in MATLAB Simulation to verify the simulation results.The proposed approach provides optimal performance with high torque and speed along with less steady state error. 展开更多
关键词 Three phase induction motor voltage source inverter improvedΓZSI with clamping diode PI controller fractional order PID controller gray wolf optimizer
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基于3D真实植被场景的全波段辐射传输模型研究 被引量:5
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作者 赵峰 顾行发 +3 位作者 刘强 余涛 陈良富 高海亮 《遥感学报》 EI CSCD 北大核心 2006年第5期670-675,共6页
本文基于3D真实场景CLAMP模型模拟的植被冠层,对冠层在可见-近红外波段和热红外波段的辐射传输进行了综合建模。针对CLAMP模型生成场景的通用和近似特征,在可见-近红外波段,对植被和土壤的单次散射贡献利用光子逆向追踪算法进行了精确计... 本文基于3D真实场景CLAMP模型模拟的植被冠层,对冠层在可见-近红外波段和热红外波段的辐射传输进行了综合建模。针对CLAMP模型生成场景的通用和近似特征,在可见-近红外波段,对植被和土壤的单次散射贡献利用光子逆向追踪算法进行了精确计算,多次散射的贡献则采用四流近似理论来计算,以提高运算效率。模型结果与SAILH模型结果进行了比较,具有较好的一致性,并且体现出了优于一维辐射传输模型的模拟结果。在热红外波段,采用几何光学原理,冠层方向亮度温度由可视光照叶片、遮荫叶片、光照土壤和遮荫土壤的比例与对应组分亮温乘积之和得到,模拟结果体现了合理的变化趋势。对冠层主要结构参数LAI和ALA的敏感性进行了比较分析,不同波段模型模拟的方向性辐射结果,很好地反映了结构参数对冠层辐射特性的影响。 展开更多
关键词 植被3D场景模拟 CLAMP模型 二向性反射分布N-Y(BRF) 方向亮度温度(DBT)
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Isolation of Protoplast and Ion Channel Recording in Plasma Membrane of Suspension Cells of Populus euphratica 被引量:4
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作者 陈少良 戴松香 +3 位作者 李金克 王沙生 Andrea Polle Aloys Hüttermann 《Forestry Studies in China》 CAS 2002年第1期1-4,共4页
The authors used suspension cells of Populus euphratica to isolate protoplast in the present study. Protoplasts were successfully obtained after 4 hours incubation in enzyme solution containing 1 0% cellulase “o... The authors used suspension cells of Populus euphratica to isolate protoplast in the present study. Protoplasts were successfully obtained after 4 hours incubation in enzyme solution containing 1 0% cellulase “onozuka” R\|10, 0\^01% pectolyase Y\|23,0\^15% macerozyme R\|10 and 0\^1% hemicellulase at 25℃. Outward and inward single channels in plasma membrane were observed using cell\|attached recording of patch\|clamp technique. In this study, single channel records showed that more than one species of channel were obtained. These attempts in protoplast isolation and ion channel recording offers the opportunity to characterize cellular mechanisms of salt tolerance in tree species. 展开更多
关键词 Populus euphratica suspension cells PROTOPLASTS patch\|clamp cell\|attached recording technique single ion channel
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POV-ray应用于冠层可视光照和阴影组分比例变化分析 被引量:2
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作者 王剑庚 赵峰 +4 位作者 李虎 余涛 顾行发 薛廉 叶李灶 《遥感学报》 EI CSCD 北大核心 2010年第2期232-251,共20页
利用POV-ray快速计算三维冠层的四分量比例及孔隙率,在与计算机模拟模型对比结果、验证其可靠性的基础上,针对植被真实结构模型的主要参数对冠层四分量比例和孔隙率的敏感性进行分析。敏感性分析结果表明:当冠层为垄行结构时,相对于其... 利用POV-ray快速计算三维冠层的四分量比例及孔隙率,在与计算机模拟模型对比结果、验证其可靠性的基础上,针对植被真实结构模型的主要参数对冠层四分量比例和孔隙率的敏感性进行分析。敏感性分析结果表明:当冠层为垄行结构时,相对于其他因素,行结构对四分量比例和孔隙率的影响占主导,因此当植被冠层为垄行结构时,四分量比例和孔隙率的变化较连续冠层更加复杂;集聚指数可以有效的控制叶片的空间分布模式,进而影响到视场中植被与土壤的相对面积比例,对于四分量比例和孔隙率结果有较大影响;叶倾角分布类型对四分量比例和孔隙率结果的各向异性特征影响明显;同时,通过对垄行作物3个典型生长期的四分量比例和孔隙率结果分析得出,在作物生长初期土壤对结果影响更大,在作物生长后期植被对结果的影响占主导,亮叶分量比例各向异性特征较为明显。研究表明,POV-ray是进行植被定量遥感研究的有利工具,具有较好的应用前景。 展开更多
关键词 POV-RAY CLAMP模型 四分量比例 孔隙率
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定量研究晚白垩世以来陆地生态系统演化格局和过程的新进展 被引量:3
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作者 孙启高 《生态学报》 CAS CSCD 北大核心 2001年第4期653-659,共7页
陆地植物的起源和演化与全球气候环境存在着密不可分的关系 ,而且地质历史时期全球气候环境和植被均呈动态变化。被子植物在白垩纪开始出现 ,并发生强烈分化 ,成为植物界的主宰 ,这对全球陆地生态系统的演化格局和过程产生重要影响。大... 陆地植物的起源和演化与全球气候环境存在着密不可分的关系 ,而且地质历史时期全球气候环境和植被均呈动态变化。被子植物在白垩纪开始出现 ,并发生强烈分化 ,成为植物界的主宰 ,这对全球陆地生态系统的演化格局和过程产生重要影响。大量保存在地层中具有叶相特征的被子植物叶化石对认识这一过程提供了极为重要的生物学信息。简述了利用被子植物的叶相对古气候、古地理等进行定量分析的研究历史。“气候与叶片多变量分析程序”( Climate-Leaf AnalysisMultivariate Program  CLAMP)颇具特色 ,运用 CLAMP在定量解释古气候等方面可以得到准确而精确的结果。这对定量重建晚白垩世以来全球陆地气候环境变化的格局与过程具有十分重要的意义 ,并对今后的深入研究作了展望。 展开更多
关键词 晚白垩世 陆地生态系统 叶相 CLAMP
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一种新型NPC非隔离光伏并网逆变器 被引量:1
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作者 林涛 《电子器件》 CAS 北大核心 2020年第6期1283-1286,共4页
三电平MPC非隔离并网逆变器具有开关损耗小、共模特性好、输出失真小等优点。提出了一种高可靠性的三电平半桥MPC逆变器,该拓扑只需要4个开关管和两个二极管就具有恒定的共模电压。更重要的是,与传统的半桥NPC逆变器相比,本文提出的拓... 三电平MPC非隔离并网逆变器具有开关损耗小、共模特性好、输出失真小等优点。提出了一种高可靠性的三电平半桥MPC逆变器,该拓扑只需要4个开关管和两个二极管就具有恒定的共模电压。更重要的是,与传统的半桥NPC逆变器相比,本文提出的拓扑结构可以在不增加死区时间的情况下避免桥臂直通问题。此外,与大多数NPC半桥逆变器和双Buck型半桥NPC逆变器相比,该拓扑具有更低的导通损耗。分析了该拓扑结构的共模模型和工作原理,证明了其优越性。最后,搭建仿真模型和实验平台验证了理论结果。 展开更多
关键词 光伏并网逆变器 NPC(Neutral Point Clamp)半桥拓扑 漏电流 直通问题 死区时间
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Effects of IQ_23 on the Repolarization and Both Components of the Delayed Rectifier Potassium Current in Guinea Pig Ventricular Myocytcs
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作者 李新华 阎升 +4 位作者 姚伟星 夏国瑾 江明性 黄文龙 彭司勋 《Journal of Chinese Pharmaceutical Sciences》 CAS 1999年第1期48-52,共5页
Using patch clamp whole cell recording techiques, we examined the effects ofIQ_23, a benzyl-isoquinoline derivative with antiarrhythmic activities, on the action potential (AP) andpotassium currents in single guinea p... Using patch clamp whole cell recording techiques, we examined the effects ofIQ_23, a benzyl-isoquinoline derivative with antiarrhythmic activities, on the action potential (AP) andpotassium currents in single guinea pig ventricular myocytes. The results showed that IQ_23 at 10, 30and 100 μmol ·L_-1 slowed the repolarization in AP dose-dependently. The APD_90 were prolonged by15%, 28% and 31% respectively. This effect did not depend on the extracellular Ca^2+. In voltageclamp mode, IQ_23 effectively blocked both the components of the delayed rectifier potassium current(I_k), i.e., I_ks and I_kr. At concentrations of 30 and 100 μmol· L^-1, IQ_23 suppressed I_ks by 21% and 26%and suppressed I_kr by 67% and 86% respectively. But even at 100 μmol·L^-1, IQ_23 had little effect onthe inward rectifier potassium current (I_k1). It is concluded: 1. IQ_23 can dose-dependently prolongAPD in the ventriculas myocytes of guinea pig, the effect does not depend on the extracellular Ca^2+; 2.IQ_23 blocks both I_ks and Ikr in the ventricular myocytes without obvious specificities between them. 展开更多
关键词 IQ_13 Antiarrhythmic drug Patch clamp technic Action potential Potassiumchannel Ventricular myocyte Guinea pig
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A NOVEL AERONAUTICAL STATIC INVERTER WITH HIGH FREQUENCY PULSE DC LINK
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作者 陈道炼 刘志政 +1 位作者 严仰光 胡育文 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第1期48-54,共7页
A new combined soft switching technique and a novel topology of aeronautical static inverter with high frequency pulse dc link are proposed in this paper, namely an electrical isolated converter can realize soft swi... A new combined soft switching technique and a novel topology of aeronautical static inverter with high frequency pulse dc link are proposed in this paper, namely an electrical isolated converter can realize soft switching of two stage cascade converters. It lays technical foundation for high power density, high efficiency and low cost aeronautical static inverter. The operation and design approach of this topology are carefully analyzed and studied. The validity of this topology is verified by simulation and test. 展开更多
关键词 INVERTERS high frequency links active clamp circuits combined soft switching techniques three state discrete pulse modulation
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