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Between Closeness and Openness --An Understanding of Guild Characteristics from the Succession of Industrial and Commercial Management Right of Baxian County in Qing Dynasty
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《长江师范学院学报》 2012年第7期138-140,共3页
关键词 《长江师范学院学报》 英文摘要 期刊 编辑工作
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Differences of Photosynthetic Characteristics of the Grape Cultivated in Greenhouse and Open Field in Turpan 被引量:3
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作者 马微 牛莹莹 +3 位作者 骆强伟 孙峰 伍国红 廖康 《Agricultural Science & Technology》 CAS 2016年第6期1285-1288,1340,共5页
[Objective] This study compared the leaf photosynthetic characteristics of Turpan grape cultivated in greenhouses and open field to provide a scientific basis for the high-quality and high-yield cultivation of grape. ... [Objective] This study compared the leaf photosynthetic characteristics of Turpan grape cultivated in greenhouses and open field to provide a scientific basis for the high-quality and high-yield cultivation of grape. [Method] Two precocious grape varieties as experimental materials were cultivated in greenhouses and open field, and their net photosynthetic rates (Pn), photo-response curves and CO2 response curves were determined using Li-400XT portable photosynthesis system. [Result] The leaf Pn of the two varieties cultivated in open field was higher than that in greenhouse. The Pn of Hongqitezao cultivated in open field was the highest, up to 19.79 μmol/(m^2·s); in the photo-response curves, Hongqitezao cultivated in greenhouse had the largest Pnmax and apparent quantum yield (AQY), while the Flame Seedless in greenhouse had the smallest light compensation point (LCP). The light saturation point (LSP) value of greenhouse cultivation was higher than that of open field cultivation. In the CO2 response test, the dark respiration rate (Rd) and Pnmax of greenhouse cultivation were higher than those of open field cultivation, and the carboxylation efficiency (CE) of greenhouse cultivation was lower than that of open field cultivation; the CO2 compensation point (CCP) and CO2 saturation point (CSP) of greenhouse cultivation were lower than those of open field cultivation. [Conclusion] The utilization of elevated light in greenhouse cultivation was more efficient than in open field cultivation; however, the utilization of elevated CO2 in greenhouse cultivation was weaker than tin open field cultivation. 展开更多
关键词 Greenhouse cultivation open field cultivation Photosynthetic characteristics Photo-response curve CO2 response curve
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Study on transient aerodynamic characteristics of parachute opening process 被引量:20
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作者 Li Yu Xiao Ming 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第6期627-633,共7页
In the research of parachute, canopy inflation process modeling is one of the most complicated tasks. As canopy often experiences the largest deformations and loa-dings during a very short time, it is of great difficu... In the research of parachute, canopy inflation process modeling is one of the most complicated tasks. As canopy often experiences the largest deformations and loa-dings during a very short time, it is of great difficulty for theoretical analysis and experimental measurements. In this paper, aerodynamic equations and structural dynamics equations were developed for describing parachute opening process, and an iterative coupling solving strategy incorpo- rating the above equations was proposed for a small-scale, flexible and flat-circular parachute. Then, analyses were carried out for canopy geometry, time-dependent pressure difference between the inside and outside of the canopy, transient vortex around the canopy and the flow field in the radial plane as a sequence in opening process. The mechanism of the canopy shape development was explained from perspective of transient flow fields during the inflation process. Experiments of the parachute opening process were conducted in a wind tunnel, in which instantaneous shape of the canopy was measured by high velocity camera and the opening loading was measured by dynamometer balance. The theoretical predictions were found in good agreement with the experimental results, validating the proposed approach. This numerical method can improve the situation of strong dependence of parachute research on wind tunnel tests, and is of significance to the understanding of the mechanics of parachute inflation process. 展开更多
关键词 PARACHUTE opening process Numerical simulation Flow field characteristics AERODYNAMICS Structural dynamics
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Study on the Availability Opening Size of Throttle and Affection to the Velocity Characteristic of Shock Absorber 被引量:3
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作者 周长城 郑志蕴 +1 位作者 顾亮 陈轶杰 《Journal of Beijing Institute of Technology》 EI CAS 2007年第1期23-27,共5页
Based on the solution of the governing differential equation for deformation of throttle slice while satisfying required boundary conditions, the coefficient (Gr) and an analytical formula for computing the deformat... Based on the solution of the governing differential equation for deformation of throttle slice while satisfying required boundary conditions, the coefficient (Gr) and an analytical formula for computing the deformation of throttle slice is presented through equivalency transformation, which is a concise, accurate and practical method for throttle slice design and characteristic analysis. Researched the deformation at any radius, compared with ANSYS FEA software by the simulation analysis, the availability opening size of throttle that was defined by the deformation at the valve mouth radius is studied. The affection of valve mouth radius to the damper characteristic is analyzed. Tests are made for the damper characteristic, compared with simulation results, it is shown that Gr method is an accurate computation method for computing the deformation of throttle slice at valve mouth radius, suitihle to use in the damper design, analysis, and verification. The deformation at mouth radius could not be replaced with the outside radius. 展开更多
关键词 DAMPER THROTTLE opening size of throttle velocity characteristic
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Visual Study on Flow and Operational Characteristics of Flat Plate Closed Loop Pulsating Heat Pipes 被引量:2
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作者 杨洪海 Groll Manfred Khandekar Sameer 《Journal of Donghua University(English Edition)》 EI CAS 2009年第1期80-84,共5页
This paper presents an experimental study including visualization on a flat plate closed loop pulsating heat pipes.It consists of a total of 40 channels with square cross section(2 mm×2 mm,165 mm long) machined d... This paper presents an experimental study including visualization on a flat plate closed loop pulsating heat pipes.It consists of a total of 40 channels with square cross section(2 mm×2 mm,165 mm long) machined directly on an aluminum plate(180 mm×120 mm×3 mm) covered by a transparent plate.The working fluid employed is ethanol.As a result,various flow patterns and their transitions are observed and found to be related to the fluid fill ratio,input heat load and the device orientation.Also the operational characteristics and working mechanism are discussed. 展开更多
关键词 flat plate closed loop pulsating heat pipes fill ratio flow patterns operational characteristics
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Value of negative pressure sealing drainage on wound healing of Gustilo IIIB and IIIC open fractures
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作者 Bo Fang Yong-Sheng Wang +2 位作者 Wei Li Kai Ying Gang Zong 《World Journal of Clinical Cases》 SCIE 2024年第20期4199-4205,共7页
BACKGROUND Gustilo III fractures have a high incidence and are difficult to treat.Patients often experience difficulty in wound healing.Negative pressure drainage technology can help shorten wound healing time and has... BACKGROUND Gustilo III fractures have a high incidence and are difficult to treat.Patients often experience difficulty in wound healing.Negative pressure drainage technology can help shorten wound healing time and has positive value in improving patient prognosis.AIM To explore the clinical value of the negative pressure sealing drainage technique in wound healing of Gustilo IIIB and IIIC open fractures.METHODS Eighty patients with Gustilo IIIB and IIIC open fractures with skin and soft tissue injuries who were treated in the Second People’s Hospital of Dalian from March 2019 to December 2021 were selected as the research subjects.They were divided into a study group(n=40,healed with negative pressure closed drainage)and a control group(n=40,healed with conventional dressing changes)according to the variation in the healing they received.The efficacy of the clinical interventions,the variations in the regression indicators(time to wound healing,time to fracture healing,time to hospitalization),and the conversion and healing of bacterial wounds were compared 1-3 mo after the intervention.RESULTS The total effective rate of patients among the study group was 95.00%(38/40),which was notably higher than 75.00%(30/40)among the control group(P<0.05).The wound healing time,fracture healing time,and hospital stay of the patients in the study group was shorter than the control group(P<0.05).After the intervention,the negative bacterial culture at the wound site rate and wound healing rate of the patients among the study group increased compared to the control group(P<0.05).CONCLUSION Negative pressure sealing and drainage technology has a good therapeutic effect on patients with Gustilo IIIB and IIIC open fracture wounds with skin and soft tissue injury.It can notably enhance the wound healing rate and the negative rate of bacteria on the wound surface and help to speed up the recovery process of patients. 展开更多
关键词 Negative pressure closed drainage Gustilo type III open fracture Wound healing Clinical outcome Research value
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On Fuzzy Regularly Closed Filters in Michálek Fuzzy Topological Space
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作者 Puthenpurackal Ratnakumar Neethu Bloomy Joseph 《Advances in Pure Mathematics》 2024年第10期779-784,共6页
C.L. Chang’s introduction of fuzzy topology in 1981 opened up new avenues for parallel theories in topology. However, Chang’s work appears to focus more on the topology of fuzzy sets rather than fuzzy topology itsel... C.L. Chang’s introduction of fuzzy topology in 1981 opened up new avenues for parallel theories in topology. However, Chang’s work appears to focus more on the topology of fuzzy sets rather than fuzzy topology itself. In 1975, Michálek presented a functional definition of ordinary topology and later developed fuzzy topology as a distinct extension of this idea, setting it apart from Chang’s approach. While there has been significant research on Chang’s fuzzy topology, Michálek’s version has not received as much attention. This paper introduces the concept of fuzzy regularly closed filters, or FRCM filters, within Michálek’s fuzzy topological space and explores some properties of FRCM ultrafilters. 展开更多
关键词 TOPOLOGY Fuzzy Topology Michálek’s Fuzzy Topological Space Fuzzy closed Fuzzy open FILTERS
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Impact of depth ratio on flow structure and turbulence characteristics of compound open channel flows
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作者 Shao-wei Ding Cheng Zeng +2 位作者 Jie Zhou Ling-ling Wang Chen Chen 《Water Science and Engineering》 EI CAS CSCD 2022年第3期265-272,共8页
Compound open channel flows appear in most natural rivers are of great importance in river management and flood control.In this study,large eddy simulations were carried out to simulate the compound open channel flows... Compound open channel flows appear in most natural rivers are of great importance in river management and flood control.In this study,large eddy simulations were carried out to simulate the compound open channel flows with four different depth ratios(hr=0.10,0.25,0.50,and 0.75).The main flow velocity,secondary flow,Reynolds stress,and bed shear stress were obtained from numerical simulations.The depth-averaged stream wise momentum equation was used to quantify the lateral momentum exchange between the main channel and floodplain.The instantaneous coherent structures were presented by the Q criterion method.The impact of hr on flow structure and turbulence charac-teristics was analyzed.The results showed that with the increase of hr,the high velocity area in the main channel shifted to the floodplain,and the dip phenomenon became more obvious;the Reynolds stress largely contributed to the lateral momentum exchange within the flows near the side walls of floodplain;and the vortex structures were found to significantly increase in the floodplain region. 展开更多
关键词 Large eddy simulation Compound open channel Depth ratio Flow structure Turbulence characteristics
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Numerical Analysis for Temperature Characteristics of Open Boundary Crushed-rock Embankment on Qinghai-Tibet Railway 被引量:1
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作者 Lai Yuanming Zhang Mingyi Liu Zhiqing Yu Wenbing 《工程科学(英文版)》 2006年第2期134-142,共9页
At present, in order to protect the stability of permafrost beneath emban kment, the crushed-rock emban kment, as a new type of emban kment structure, has widely been used in the construction of Qinghai-Tibet Railway.... At present, in order to protect the stability of permafrost beneath emban kment, the crushed-rock emban kment, as a new type of emban kment structure, has widely been used in the construction of Qinghai-Tibet Railway. Its crushed-rock layer is almost open in tow bilateral boundaries and closed at top and bottom, and air can flow into/out of the ballast layer and crushed-rock layer. Therefore, the convection and transfer heat patterns are very complicated in the ballast layer and crushed-rock layer of the emban kment, which are regarded as porous media. In this paper, based on the wind, temperature and geology conditions of Qinghai-Tibet Plateau, a numerical approach of the unsteady two-dimensional continuity, momentum (non-Darcy flow) and energy equations of heat convection for incompressible fluid in porous media is provide to analyse the velocity and temperature characteristics of the crushed-rock emban kment with different emban kment heights under open boundary condition for the coming 50 years. The calculated results indicate that, due to the influence of the external wind, the convective heat transfer mainly relies on the forced convection in the open crushed-rock emban kment. Even if the air temperature will be warmed up by 2.6℃ in the coming 50 years, it still has a better cooling effect on the underlying soils and a low temperature frozen-soil core is formed in the permafrost below it if the emban kment is constructed in the regions whose present mean annual air temperature is -4.0℃. Furthermore, the cooling effect of high crushed-rock emban kment is better than that of low emban kment. This results from the fact that the wider bottom of high emban kment has a more influence dimension on the underlying frozen soil. However, cardinal winds on Qinghai-Tibet Plateau disturb its convection pattern, so that an asymmetric temperature distribution occurs under high emban kment and it is possible to induce a transverse uneven deformation of emban kment, but no similar situation occurs under low emban kment. This asymmetric temperature field problem should be considered when crushed-rock emban kment is designed and constructed. 展开更多
关键词 青藏铁路 开放边界碎石堤防 温度特性 数值分析
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The Structural Characteristics of Side-Opening Costumes during the Republic Period of China
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作者 亓延 范雪荣 崔荣荣 《Journal of Donghua University(English Edition)》 EI CAS 2011年第6期632-635,共4页
The structural characteristics of Chinese side-opening costumes during the Republic Period of China were investigated.By measuring and recovering the physical structures of side-opening costume objects from the Folk C... The structural characteristics of Chinese side-opening costumes during the Republic Period of China were investigated.By measuring and recovering the physical structures of side-opening costume objects from the Folk Costumes Biography Museum of Jiangnan University,three structural characteristics were analyzed.These structural characteristics show that most of the side-opening costumes during the Republic Period of China remain traditional Chinese costume structures.The general structural characteristics of side-opening costumes are concluded and the structural cutting methods can inspire current designs as well as provide useful references for contemporary fashion designers. 展开更多
关键词 structural characteristics side-opening costume Republic Period of China structural wholeness
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Taking the Path of Poverty Reduction with Chinese Characteristics to Promote New Progress in China's Human Rights——A Keynote Speech at the Opening Ceremony of 2018 Beijing Forum on Human Rights
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作者 向巴平措 HU Liang(译) 《The Journal of Human Rights》 2018年第6期603-606,共4页
The 2018 Beijing Forum on Human Rights opens on this wonderful autumn day.On behalf of the China Society for Human Rights Studies, I wish to express warm congratulations on the opening of the forum and a sincere welco... The 2018 Beijing Forum on Human Rights opens on this wonderful autumn day.On behalf of the China Society for Human Rights Studies, I wish to express warm congratulations on the opening of the forum and a sincere welcome to all guests from home and abroad. 展开更多
关键词 Taking the Path of Poverty Reduction with Chinese characteristics to Promote New Progress in China’s Human Rights A Keynote Speech at the opening Ceremony of 2018 Beijing Forum on Human Rights
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XI JINPING THOUGHT ON SOCIALISM WITH CHINESE CHARACTERISTICS FOR A NEW ERA OPENS NEW HORIZON FOR INTERNATIONAL COMMUNIST MOVEMENT
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作者 LV WEIZHOU 《Contemporary World》 2018年第2期2-5,共4页
The 19th National Congress of the Communist Party of China (CPC) established Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era as the guiding ideol- ogy of the CPC, marking a new leap forwar... The 19th National Congress of the Communist Party of China (CPC) established Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era as the guiding ideol- ogy of the CPC, marking a new leap forward in synthesizing basic principles of Marxism with China's concrete conditions. This Thought enriches and develops scientific socialism, the guiding ideology of the International Communist Movement. With brave new intellectual horizon, it deepens the understanding of the laws governing government by communist parties, construction of socialism and development of human society, occupying an important place of historical significance in the history of development of Marxism and the International Communist Movement. Guided by Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era, socialism with Chinese characteristics has made great historical achievements, creating new splendor and helping open new vista for the International Communist Movement. 展开更多
关键词 XI JINPING CHINESE HARACTERISTICS
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OPEN表和CLOSED表的合一 被引量:2
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作者 冯乃勤 王岁花 +1 位作者 郑延斌 冯国燚 《计算机工程与应用》 CSCD 北大核心 2003年第16期100-101,125,共3页
在人工智能传统的搜索方法中,一直是将OPEN表和CLOSED表分开的。这不仅增加了搜索算法的复杂性,久而久之,也许禁锢了人们的思想。文章试图改变这种状况,提出了一种与众不同的新思路,巧妙地将OPEN表和CLOSED表合二为一,减少了一些工作量... 在人工智能传统的搜索方法中,一直是将OPEN表和CLOSED表分开的。这不仅增加了搜索算法的复杂性,久而久之,也许禁锢了人们的思想。文章试图改变这种状况,提出了一种与众不同的新思路,巧妙地将OPEN表和CLOSED表合二为一,减少了一些工作量,在一定程度上降低了算法的复杂性。 展开更多
关键词 搜索 0PEN表 closeD表 算法复杂性
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The Fuzzy Neural Network Control Scheme With H∞ Tracking Characteristic of Space Robot System With Dual-arm After Capturing a Spin Spacecraft 被引量:1
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作者 Jing Cheng Li Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2020年第5期1417-1424,共8页
In this paper,the dynamic evolution for a dualarm space robot capturing a spacecraft is studied,the impact effect and the coordinated stabilization control problem for postimpact closed chain system are discussed.At f... In this paper,the dynamic evolution for a dualarm space robot capturing a spacecraft is studied,the impact effect and the coordinated stabilization control problem for postimpact closed chain system are discussed.At first,the pre-impact dynamic equations of open chain dual-arm space robot are established by Lagrangian approach,and the dynamic equations of a spacecraft are obtained by Newton-Euler method.Based on the results,with the process of integral and simplify,the response of the dual-arm space robot impacted by the spacecraft is analyzed by momentum conservation law and force transfer law.The closed chain system is formed in the post-impact phase.Closed chain constraint equations are obtained by the constraints of closed-loop geometry and kinematics.With the closed chain constraint equations,the composite system dynamic equations are derived.Secondly,the recurrent fuzzy neural network control scheme is designed for calm motion of unstable closed chain system with uncertain system parameter.In order to overcome the effects of uncertain system inertial parameters,the recurrent fuzzy neural network is used to approximate the unknown part,the control method with H∞tracking characteristic.According to the Lyapunov theory,the global stability is demonstrated.Meanwhile,the weighted minimum-norm theory is introduced to distribute torques guarantee that cooperative operation between manipulators.At last,numerical examples simulate the response of the collision,and the efficiency of the control scheme is verified by the simulation results. 展开更多
关键词 Capturing operation calm motion control closed chain system dual-arm space robot recurrent fuzzy neural network H∞tracking characteristic
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Internal Lateral Sphincterotomy in Yaounde: Comparative Short-Term Results of Open versus Closed Techniques 被引量:1
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作者 Georges Bwelle Motto Yannick Mahamat Ekani Boukar +4 位作者 Guy Aristide Bang Joseph Cyrille Chopkeng Ngoumfe Fabrice Tientcheu Tim Arthur Essomba Maurice Aurélien Sosso 《Surgical Science》 2021年第11期374-380,共7页
<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:Verdana;"></span><b> </b><span style="font-family:Verdan... <b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:Verdana;"></span><b> </b><span style="font-family:Verdana;">Chronic anal fissure is a benign disorder which is associated with considerable discomfort. </span><span style="font-family:Verdana;"><b></b></span><b><b><span style="font-family:Verdana;">Aim of the Work:</span></b><span style="font-family:;" "=""><span style="font-family:Verdana;"></span></span></b><b> </b><span style="font-family:;" "=""><span style="font-family:Verdana;">The aim of this study was to compare the post-operative results of open and closed internal lateral sphincterotomies in the short and medium term.</span><b> </b></span><span style="font-family:Verdana;"><b></b></span><b><b><span style="font-family:Verdana;">Patient and Methods:</span></b><span style="font-family:;" "=""><span style="font-family:Verdana;"></span></span></b><b> </b><span style="font-family:Verdana;">We carried out a prospective randomized comparative study in the digestive and visceral surgery departments of Central Hospital of Yaounde over a period of 15</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">months. Patients were evaluated for each technique by several variables, including duration of surgery, post-operative pain, recurrence, surgical wound infection, gas and/or stool incontinence, and healing time with follow-up up to 12</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">months postoperatively.</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;"><b></b></span><b><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:;" "=""><span style="font-family:Verdana;"></span></span></b><b> </b><span style="font-family:Verdana;">A total of 63 patients underwent surgery within them we had 32 open lateral internal sphincterotom</span><span style="font-family:Verdana;">ies</span><span style="font-family:Verdana;"> (group 1) and 31 closed lateral internal sphincterotom</span><span style="font-family:Verdana;">ies</span><span style="font-family:Verdana;"> (group 2). There were 35 men and 28 women with a sex ratio of 1.25. The mean age was 35.36 ± 10.16 years with extremes ranging from 19 to 62 years. The typical presentation was pain on defecation. The majority of fissures were located at the posterior commissure. The average duration of the procedure was longer in patients in group 1 (15.34 minutes) compared to 5.22 minutes in patients in group 2. We found 3.12% of surgical wound infections in patients in group 1 and neither patient in group 2. Gas incontinence was 6.45% in group 2 patients and 28.12% in group 1.</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">The mean intensity of pain at 24 hours post-operative was between</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">4 and 6 on </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">visual analogue scale in patients in group 2 and between 7 and 10 in group 1. Wound healing time was 8.9 days in group </span><span style="font-family:Verdana;">1</span><span style="font-family:Verdana;"> and 4 days in group 2 patients. The hospital stay was 24 hours for both groups of patients. No recurrence was noted during the 6-month</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">follow-up period.</span><b> </b></span><span style="font-family:;" "=""><span style="font-family:Verdana;"><b></b></span><b><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"></span></b></span><b> </b><span style="font-family:Verdana;">Closed lateral internal anal sphincterotomy is the treatment of choice for chronic anal fissures because it is effective and associated with </span><span style="font-family:Verdana;">a </span><span style="font-family:Verdana;">lower complication rate than the open sphincterotomy technique.</span> 展开更多
关键词 Anal Fissure Internal Lateral Sphincterotomy open Technique close Technique
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Major Characteristics of the Lajishan Orogenic Belt of the South Qilian Mountains and Its Geotectonic Attribute 被引量:12
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作者 杨巍然 邓清禄 吴秀玲 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2002年第1期110-117,共8页
The Lajishan orogenic belt is one of the E-W-trending Caledonian orogenicbelts within the Qinling-Qilian orogenic system. It was formed upon the Jiningian basement byintensive taphrogenesis. Its major characteristics ... The Lajishan orogenic belt is one of the E-W-trending Caledonian orogenicbelts within the Qinling-Qilian orogenic system. It was formed upon the Jiningian basement byintensive taphrogenesis. Its major characteristics comprise the prominent faulting along the northand south boundaries, the highly complicated petrological and petro-geochemical features of thevolcanic rock series, and the development of a new type of ophiolite suite. In terms of tectonicanalysis and the sequential analysis of tectonic settings of magmatic rocks, it is suggested thatthe Lajishan orogenic belt has undergone a complete 'opening-closing' cycle, which can be furtherdivided into 3 second-order 'opening-closing' cycles. The composite characteristics of the'opening-closing' movement show that Laji Mountain is a typical fault orogenic belt. The faultorogenic belt is one of the most important types of intracontinental orogens. It is of criticaltheoretical and practical significance to summarize the characteristics and the diagnostic criteriaof this kind of orogenic belts, and study the mechanism of their formation and build models of theirevolution. 展开更多
关键词 south Qilian Mountains Laji Mountain orogenic belt 'opening-and-closing' tectonic analysis tectonic setting geotectonic attribute
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Open-closed Loop ILC Corrected with Angle Relationship of Output Vectors for Tracking Control of Manipulator 被引量:8
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作者 WANG Hong-Bin WANG Yan 《自动化学报》 EI CSCD 北大核心 2010年第12期1758-1765,共8页
关键词 ILC 自动化 跟踪控制 仿真
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Burning characteristics of microcellular combustible objects 被引量:1
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作者 Wei-tao YANG Yu-xiang LI San-jiu YING 《Defence Technology(防务技术)》 SCIE EI CAS 2014年第2期106-110,共5页
Microcellular combustible objects for application of combustible case,caseless ammunition or combustible detonator-holding tubes are fabricated through one-step foaming process,in which supercritical CO_2 is used as f... Microcellular combustible objects for application of combustible case,caseless ammunition or combustible detonator-holding tubes are fabricated through one-step foaming process,in which supercritical CO_2 is used as foaming agent.The formulations consist of inert polymer binder and ultra fine RDX.For the inner porous structures of microcellular combustible objects,the cell sizes present a unimodal or bimodal distribution by adjusting the foaming conditions.Closed bomb test is to investigate the influence of both porous structure style and RDX content on burning behavior.The sample with bimodal distribution of cell sizes burns faster than that with unimodal distribution,and the concentration of RDX can influence the burning characteristics in a positive manner.In addition,the translation of laminar burning to convective burning is determined by burning rate versus pressure curves of samples at two different loading densities,and the resulting transition pressure is 30 MPa.Moreover,the samples with bigger sample size present higher burning rate,resulting in providing deeper convective depth.Dynamic vivacity of samples is also studied.The results show that the vivacity increases with RDX content and varies with inner structure. 展开更多
关键词 燃烧性能 可燃物 超临界二氧化碳 发泡过程 多孔结构 双峰分布 单峰分布 压力曲线
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Open-plus-closed-loop control for chaotic motion of 3D rigid pendulum 被引量:2
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作者 戈新生 邹奎 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第4期403-412,共10页
An open-plus-closed-loop (OPCL) control problem for the chaotic motion of a 3D rigid pendulum subjected to a constant gravitationM force is studied. The 3D rigid pendulum is assumed to be consist of a rigid body sup... An open-plus-closed-loop (OPCL) control problem for the chaotic motion of a 3D rigid pendulum subjected to a constant gravitationM force is studied. The 3D rigid pendulum is assumed to be consist of a rigid body supported by a fixed and frictionless pivot with three rotational degrees. In order to avoid the singular phenomenon of Euler's angular velocity equation, the quaternion kinematic equation is used to describe the motion of the 3D rigid pendulum. An OPCL controller for chaotic motion of a 3D rigid pendulum at equilibrium position is designed. This OPCL controller contains two parts: the open-loop part to construct an ideal trajectory and the closed-loop part to stabilize the 3D rigid pendulum. Simulation results show that the controller is effective and efficient. 展开更多
关键词 3D rigid pendulum QUATERNION chaotic motion Poincar section open-plus-closed-loop (OPCL) control
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TRANSFER OPEN OR CLOSED SETVALUED MAPPING AND GENERALIZ-ATION OF H-KKM THEOREM WITH APPLICATIONS
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作者 李秉友 苏家宝 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第10期981-987,共7页
In this paper ,we introduce a class of generalized mapping called transfer open orclosed valued mapping to generalize the KKM theorem on H-space.Then asapplications,using our H-KKM theorem,we prove some coincidence th... In this paper ,we introduce a class of generalized mapping called transfer open orclosed valued mapping to generalize the KKM theorem on H-space.Then asapplications,using our H-KKM theorem,we prove some coincidence theorems.matching theorems and vector valued minimax inequalities which generalize slightly thecorresponding results in[1,2,4,5,6,7]. 展开更多
关键词 transfer closed or open setvalued mapping coincidence theorem.H-KKM mapping matching theorem
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