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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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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 算法复杂性
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CONDENSING HEAT TRANSFER IN AN ADVANCED TWO-PHASE CLOSED THERMOSYPHON 被引量:1
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作者 李修伦 闻建平 +1 位作者 单岩昆 黄鸿鼎 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1996年第1期88-92,共5页
1 INTRODUCTIONClosed thermosyphon has been developed to enhance heat transfer and recover wasteheat in various process industries [1,2].Stimulated by this success,a new type oftwo-phase closed thermosyphon was designe... 1 INTRODUCTIONClosed thermosyphon has been developed to enhance heat transfer and recover wasteheat in various process industries [1,2].Stimulated by this success,a new type oftwo-phase closed thermosyphon was designed by inserting respectively two inner tubesinto the thermosyphon,one in the boiling section and the other in the condensing sec-tion.The two-phase flow boiling heat transfer coefficient was calculated successfully onthe basis of Chen’s dual-mechanism [3].A boiling heat transfer model for thetwo-phase closed thermosyphon with an inner tube in the boiling section was pro- 展开更多
关键词 TWO-PHASE closed THERMOSYPHON heat transfer NARROW ANNULUS
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Fluid Flow and Mixed Heat Transfer in a Horizontal Channel with an Open Cavity and Wavy Wall
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作者 Tohid Adibi Shams Forruque Ahmed +3 位作者 Omid Adibi Hassan Athari Irfan Anjum Badruddin Syed Javed 《Intelligent Automation & Soft Computing》 SCIE 2023年第7期147-163,共17页
Heat exchangers are utilized extensively in different industries and technologies.Consequently,optimizing heat exchangers has been a major concern among researchers.Although various studies have been conducted to impr... Heat exchangers are utilized extensively in different industries and technologies.Consequently,optimizing heat exchangers has been a major concern among researchers.Although various studies have been conducted to improve the heat transfer rate,the use of a wavy wall in the presence of different types of heat transfer mechanisms has not been investigated.This study thus investigates the mixed heat transmission behavior of fluid in a horizontal channel with a cavity and a hot,wavy wall.The fluid flow in the channel is considered laminar,and the governing equations including continuity,momentum,and energy are all solved numerically.The numerical solution is stabilized by using a first-order multi-dimensional characteristic-based scheme in combination with a fifth-order Runge-Kutta method.The flow and heat transfer effects of varying Richardson numbers,Reynolds numbers,wave amplitude,wavelength,channel height,and cavity width are examined.The results indicate that the mean Nusselt number increases with an increase in Reynolds number,wave amplitude,and cavity width,while it decreases with an increase in Richardson number,wavelength,and channel height.The minimum Nusselt number is calculated to be 0.7,whereas the maximum Nusselt number is 27.09.The Nusselt number has only increased by 40%in the higher depths of the cavity,despite the Richardson number being 10,000 times larger.But this figure increases to 130%at lower depths.The mean Nusselt number is thus significantly influenced by channel height and cavity width.The influence of wave amplitude on the mean Nusselt number is twice that of wavelength. 展开更多
关键词 Mixed heat transfer wavy wall horizontal channel open cavity numerical simulation
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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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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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Understanding the correlation between energy-state mismatching and open-circuit voltage loss in bulk heterojunction solar cells
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作者 Hyun-Seock Yang Danbi Kim +7 位作者 Chang-Mok Oh Vellaiappillai Tamilavan Pesi MHangoma Hojun Yi Bo RLee Insoo Shin In-Wook Hwang Sung Heum Park 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期164-174,共11页
Photoinduced intermolecular charge transfer(PICT)determines the voltage loss in bulk heterojunction(BHJ)organic photovoltaics(OPVs),and this voltage loss can be minimized by inducing efficient PICT,which requires ener... Photoinduced intermolecular charge transfer(PICT)determines the voltage loss in bulk heterojunction(BHJ)organic photovoltaics(OPVs),and this voltage loss can be minimized by inducing efficient PICT,which requires energy-state matching between the donor and acceptor at the BHJ interfaces.Thus,both geometrically and energetically accessible delocalized state matching at the hot energy level is crucial for achieving efficient PICT.In this study,an effective method for quantifying the hot state matching of OPVs was developed.The degree of energy-state matching between the electron donor and acceptor at BHJ interfaces was quantified using a mismatching factor(MF)calculated from the modified optical density of the BHJ.Furthermore,the correlation between the open-circuit voltage(Voc)of the OPV device and energy-state matching at the BHJ interface was investigated using the calculated MF.The OPVs with small absolute MF values exhibited high Voc values.This result clearly indicates that the energy-state matching between the donor and acceptor is crucial for achieving a high Voc in OPVs.Because the MF indicates the degree of energy-state matching,which is a critical factor for suppressing energy loss,it can be used to estimate the Voc loss in OPVs. 展开更多
关键词 bulk heterojunction open circuit voltage organic photovoltaics photoinduced charge transfer voltage loss
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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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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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A screw dislocation near one open inhomogeneity and another closed inhomogeneity both permitting constant interior stresses
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作者 Xu WANG Ping YANG P.SCHIAVONE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第2期173-182,共10页
We prove that the interior stresses within both a non-parabolic open inhomogeneity and another interacting non-elliptical closed inhomogeneity can still remain constant when the matrix is simultaneously under the acti... We prove that the interior stresses within both a non-parabolic open inhomogeneity and another interacting non-elliptical closed inhomogeneity can still remain constant when the matrix is simultaneously under the action of a screw dislocation and uniform remote anti-plane stresses.The constancy of interior stresses is realized through the construction of a conformal mapping function for the doubly connected domain occupied by the surrounding matrix.The mapping function is endowed with the information describing the screw dislocation via the incorporation of two specifically defined logarithmic terms.The constant interior stress fields are observed to be independent of the specific open and closed shapes of the two inhomogeneities and the existence of the screw dislocation.In contrast,the existence of the neighboring screw dislocation significantly affects the open and closed shapes of the two inhomogeneities. 展开更多
关键词 constant stress field open inhomogeneity closed inhomogeneity screw dislocation conformal mapping
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Free torsion of thin-walled structural members of open-and closed-sections
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作者 Long-yuan LI D.EASTERBROOK 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第1期25-32,共8页
Free torsion of thin-walled structures of open- and closed-sections is a classical elastic mechanics problem, which, in literature, is often solved by the method of membrane analogy. The method of membrane analogy, ho... Free torsion of thin-walled structures of open- and closed-sections is a classical elastic mechanics problem, which, in literature, is often solved by the method of membrane analogy. The method of membrane analogy, however, can be only applied to structures of a single material. If the structure consists of both open- and closed-sections, the method of membrane analogy is difficult to be applied. In this paper, a new method is presented for solving the free torsion of thin-walled structures of open- and/or closed- sections with multiple materials. By utilizing a simple statically indeterminate concept, torsional equations are derived based on the equilibrium and compatibility conditions. The method presented here not only is very simple and easy to understand but also can be applied to thin-walled structures of combined open- and closed-sections with multiple materials. 展开更多
关键词 TORSION THIN-WALLED open-section closed-section shear flow shear stress
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Changes in neurological and pathological outcomes in a modified rat spinal cord injury model with closed canal 被引量:1
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作者 Xin Sun Xing-Zhen Liu +4 位作者 Jia Wang Hai-Rong Tao Tong Zhu Wen-Jie Jin Kang-Ping Shen 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第4期697-704,共8页
Most animal spinal cord injury models involve a laminectomy,such as the weight drop model or the transection model.However,in clinical practice,many patients undergo spinal cord injury while maintaining a relatively c... Most animal spinal cord injury models involve a laminectomy,such as the weight drop model or the transection model.However,in clinical practice,many patients undergo spinal cord injury while maintaining a relatively complete spinal canal.Thus,open spinal cord injury models often do not simulate real injuries,and few previous studies have investigated whether having a closed spinal canal after a primary spinal cord injury may influence secondary processes.Therefore,we aimed to assess the differences in neurological dysfunction and pathological changes between rat spinal cord injury models with closed and open spinal canals.Sprague-Dawley rats were randomly divided into three groups.In the sham group,the tunnel was expanded only,without inserting a screw into the spinal canal.In the spinal cord injury with open canal group,a screw was inserted into the spinal canal to cause spinal cord injury for 5 minutes,and then the screw was pulled out,leaving a hole in the vertebral plate.In the spinal cord injury with closed canal group,after inserting a screw into the spinal canal for 5 minutes,the screw was pulled out by approximately 1.5 mm and the flat end of the screw remained in the hole in the vertebral plate so that the spinal canal remained closed;this group was the modified model,which used a screw both to compress the spinal cord and to seal the spinal canal.At 7 days post-operation,the Basso-Beattie-Bresnahan scale was used to measure changes in neurological outcomes.Hematoxylin-eosin staining was used to assess histopathology.To evaluate the degree of local secondary hypoxia,immunohistochemical staining and western blot assays were applied to detect the expression of hypoxia-inducible factor 1α(HIF-1α)and vascular endothelial growth factor(VEGF).Compared with the spinal cord injury with open canal group,in the closed canal group the Basso-Beattie-Bresnahan scores were lower,cell morphology was more irregular,the percentage of morphologically normal neurons was lower,the percentages of HIF-1α-and VEGF-immunoreactive cells were higher,and HIF-1αand VEGF protein expression was also higher.In conclusion,we successfully established a rat spinal cord injury model with closed canal.This model could result in more serious neurological dysfunction and histopathological changes than in open canal models.All experimental procedures were approved by the Institutional Animal Care Committee of Shanghai Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine,China(approval No.HKDL201810)on January 30,2018. 展开更多
关键词 Basso-Beattie-Bresnahan scores closed SPINAL CANAL HIF-1α hypoxia MODEL nerve regeneration open SPINAL CANAL rat secondary INJURY SPINAL cord INJURY VEGF
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Analysis of the Heat Transfer Efficiency of an Automobile Engine under Different Grille Opening and Closing Conditions 被引量:1
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作者 Jian Song 《Fluid Dynamics & Materials Processing》 EI 2022年第2期345-354,共10页
Computational Fluid Dynamics is used to assess the thermal(heat transfer)performances of an automobile engine considering different grille opening and closing degrees.For this purpose the entire vehicle is modelled an... Computational Fluid Dynamics is used to assess the thermal(heat transfer)performances of an automobile engine considering different grille opening and closing degrees.For this purpose the entire vehicle is modelled and three fundamental aspects are examined,namely,the open area of the air intake grille,the position of the upper and lower grilles and their shape.The results show that the opening area and position of the grille have some influence also on the aerodynamic characteristics of the automobile.With an increase in the opening angle of the grille,the CD(Drag Coefficient)value of the whole vehicle becomes higher.When the air intake grille of the car is fully open or closed,the CD value is 0.35434 or 0.31777,respectively,that is,the flow resistance in the engine compartment accounts for 10.32%of the CD value for the whole automobile. 展开更多
关键词 Air intake grille opening and closing degree automobile engine heat transfer function simulation and optimization
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An Research on the Model Design of the Academic Education's Credit Transfer in the Open University 被引量:1
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作者 Houhong Sun 《Review of Educational Theory》 2018年第1期13-15,共3页
Based on the analyses of the credit bank both at home and abroad, explore the effective way to construct the credit transfer model, find out the main problems in the process of transferring, design a much better model... Based on the analyses of the credit bank both at home and abroad, explore the effective way to construct the credit transfer model, find out the main problems in the process of transferring, design a much better model, formulate a new standard for credit transfer and carry out the research on the model design of the academic education's credit transfer in the open university. 展开更多
关键词 CREDIT transfer The open UNIVERSITY Model DESIGN RESEARCH
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A KY FAN MATCHING THEOREM FOR TRANSFER COMPACTLY OPEN COVERS AND THE APPLICATION TO THE FIXED POINT 被引量:18
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作者 文开庭 《数学物理学报(A辑)》 CSCD 北大核心 2006年第B12期1159-1165,共7页
In this article, a Ky Fan matching theorem for transfer compactly open covers is established. As applications, a Fan-Browder coincidence theorem, a Ky Fan best approximation theorem and a Brouwer-Schauder-Rothe type f... In this article, a Ky Fan matching theorem for transfer compactly open covers is established. As applications, a Fan-Browder coincidence theorem, a Ky Fan best approximation theorem and a Brouwer-Schauder-Rothe type fixed point theorem are obtained. 展开更多
关键词 超凸度量空间 最优逼近 固定点 匹配定理
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Nuclephilic ring opening of epoxides promoted by multi-site phase-transfer catalyst:An efficient and eco-friendly route to synthesis of β-hydroxythiocyanate 被引量:2
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作者 Ali Reza Kiasat Roya Mirzajani +1 位作者 Haji Shalbaf Tahereh Tabatabaei 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第9期1025-1029,共5页
A highly effective and mild protocol for ring opening of epoxides with NH4SCN in the presence of catalytic amount of a multi- site phase-transfer catalyst, α,α',α"-N-hexakis(triethylammoniummethylene chloride)-... A highly effective and mild protocol for ring opening of epoxides with NH4SCN in the presence of catalytic amount of a multi- site phase-transfer catalyst, α,α',α"-N-hexakis(triethylammoniummethylene chloride)-melamine, is developed. A variety of ^-hydroxy thiocyanates as important intermediates in agricultural and pharmaceutical chemistry were obtained in high yields with excellent regioselectivity and in short reaction times. 2009 Ali Reza Kiasat. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 Multi-site phase-transfer catalyst β-Hydroxythiocyanate Thiocyanohydrin EPOXIDE Ring opening Regioselectivity
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Parametric Influence on Thermal Performance of Flat Plate Closed Loop Pulsating Heat Pipes 被引量:2
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作者 杨洪海 KHANDEKAR Sameer GROLL Manfred 《Journal of Donghua University(English Edition)》 EI CAS 2006年第3期8-13,共6页
This paper presents an experimental study on a flat plate closed loop pulsating heat pipes. It consisted of total 40 channels with square cross section(2×2 mm2, 165 mm long) machined directly on an aluminum plate... This paper presents an experimental study on a flat plate closed loop pulsating heat pipes. It consisted of total 40 channels with square cross section(2×2 mm2, 165 mm long) machined directly on an aluminum plate(180×120×3 mm3), which was covered by a transparent plate. The working fluid employed was ethanol. As the results, the influence parameters of thermal performance were investigated, such as filling ratio, heat load and operational orientations etc. Filling ratio was found to be a critical parameter, and its effect was rather complicated. According to its values the PHP plate could have four distinct working zones with different operational characteristics and heat transfer performance. The effect of heat load on thermal performance was found to be positive, and in general, increasing the heat load would improve heat transfer performance. In order to analyze the effect of gravity on thermal performance, three different heat modes and total seven tilt angles were tested and compared. Successful operation at all orientations with respect to gravity was also achieved. 展开更多
关键词 平板闭环脉动热管 参数影响 热转变特征 PCBS
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Heat Transfer and Acoustic Properties of Open Cell Aluminum Foams
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作者 Bokhyun KANG Kiyoung KIM Byungmin LEE Jaesoo NOH 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第1期1-6,共6页
The aluminum open cell foams have been prepared by the conventional precision casting method to investigate the thermal and acoustic properties.A water heating system and silencers were organized as a first step for i... The aluminum open cell foams have been prepared by the conventional precision casting method to investigate the thermal and acoustic properties.A water heating system and silencers were organized as a first step for its applications.The temperature increase between the top and bottom of the foam became larger as the cell size increased in the heat transfer measurement.Sound absorption ratio of the close cell foams was 60%-100%, whereas the open cell aluminum foam showed only 10%-20% of sound absorption at low frequency.When the prototype electric water heater manufactured by combining aluminum open cell foam with a heater was heated to 100-400℃,the highest temperature of water was in the range of 16-46~C.This suggests that there could be potential for this type of heater to be used as a commercial electric water heater.Sound silencer made with the aluminum open cell foam was applied to exit of exhaustion side at air pressure line.Sound silencing effect of open-celled aluminum foam showed that the noise level went down by introducing smaller cell size foam. 展开更多
关键词 open cell aluminum foam Heat transfer property Sound absorption Electricwater heater Sound silencer
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Temperature distribution of fluids in a two-section two-phase closed thermosyphon wellbore
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作者 Zhang Yufeng Zhao Lun +5 位作者 Fan Zifei Wu Xiaodong Fu Libing Xu Bifeng Kong Fanshun Jiang Shengdong 《Petroleum Science》 SCIE CAS CSCD 2014年第2期287-292,共6页
Compared with a conventional single section two-phase closed thermosyphon (TPCT) wellbore, a two-section TPCT wellbore has better heat transfer performance, which may improve the temperature distribution of fluid in... Compared with a conventional single section two-phase closed thermosyphon (TPCT) wellbore, a two-section TPCT wellbore has better heat transfer performance, which may improve the temperature distribution of fluid in wellbores, increase the temperature of fluid in wellheads and even more effectively reduce the failure rate of conventional TPCT wellbores. Heat transfer performance of two-section TPCT wellbores is affected by working medium, combination mode and oil flow rate. Different working media are introduced into the upper and lower TPCTs, which may achieve a better match between the working medium and the temperature field in the wellbores. Interdependence exists between the combination mode and the flow rate of the oil, which affects the heat transfer performance of a two-section TPCT wellbore. The experimental results show that a two-section TPCT wellbore, with equal upper and lower TPCTs respectively filled with Freon and methanol, has the best heat transfer performance when the oil flow rate is 200 L/h. 展开更多
关键词 Two-section two-phase closed thermosyphon temperature distribution combination mode heat transfer performance
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Psychosocial Factors Associated with Transfer Anxiety among Open Heart Surgery Patients Transferred from the Intensive Care Unit to the General Ward
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作者 Jaya Rijal Wipa Sae-Sia Luppana Kitrungrote 《Health》 2020年第12期1583-1597,共15页
<strong>Introduction:</strong> Patient’s transfer from the intensive care unit (ICU) to the general ward indicates their improving health status. However, the transfer produces anxiety when patients enter... <strong>Introduction:</strong> Patient’s transfer from the intensive care unit (ICU) to the general ward indicates their improving health status. However, the transfer produces anxiety when patients enter an unfamiliar environment with different care protocols and circumstances. <strong>Objectives:</strong> This study aimed to examine the level of ICU transfer anxiety among open heart surgery patients and determine the psychosocial factors associated with ICU transfer anxiety among open heart surgery patients. <strong>Methods:</strong> Data were collected in a cardiac center in Kathmandu City, Nepal among 95 open heart surgery patients within 24 hours of their transfer from an ICU to a general ward. The study used four self-reported questionnaires, namely the modified Mishel Uncertainty in Illness Scale for Adults, modified Brief COPE Inventory, Nurses’ Support Questionnaire, and State Anxiety Inventory. <strong>Results:</strong> Fifty-two patients (54.7%) had a high level of transfer anxiety. Spearman’s rank correlation showed that uncertainty in illness, coping, and nurses’ support were significantly related to transfer anxiety (<em>p</em> < 0.001). <strong>Conclusion:</strong> The results of this study suggest nurses to address uncertainty in illness of the patients, improve their coping abilities, and provide need-based nursing support to them during the transitional phase. Besides, clinicians and governmental agencies should contribute to implication of transitional guidelines, which can reduce transfer anxiety and promote health and recovery of the patients. 展开更多
关键词 transfer Anxiety UNCERTAINTY COPING Intensive Care Unit open Heart Surgery
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