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Optimizing Grey Wolf Optimization: A Novel Agents’ Positions Updating Technique for Enhanced Efficiency and Performance
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作者 Mahmoud Khatab Mohamed El-Gamel +2 位作者 Ahmed I. Saleh Asmaa H. Rabie Atallah El-Shenawy 《Open Journal of Optimization》 2024年第1期21-30,共10页
Grey Wolf Optimization (GWO) is a nature-inspired metaheuristic algorithm that has gained popularity for solving optimization problems. In GWO, the success of the algorithm heavily relies on the efficient updating of ... Grey Wolf Optimization (GWO) is a nature-inspired metaheuristic algorithm that has gained popularity for solving optimization problems. In GWO, the success of the algorithm heavily relies on the efficient updating of the agents’ positions relative to the leader wolves. In this paper, we provide a brief overview of the Grey Wolf Optimization technique and its significance in solving complex optimization problems. Building upon the foundation of GWO, we introduce a novel technique for updating agents’ positions, which aims to enhance the algorithm’s effectiveness and efficiency. To evaluate the performance of our proposed approach, we conduct comprehensive experiments and compare the results with the original Grey Wolf Optimization technique. Our comparative analysis demonstrates that the proposed technique achieves superior optimization outcomes. These findings underscore the potential of our approach in addressing optimization challenges effectively and efficiently, making it a valuable contribution to the field of optimization algorithms. 展开更多
关键词 Grey Wolf Optimization (GWO) Metaheuristic Algorithm Optimization Problems Agents’ positions Leader Wolves Optimal Fitness Values Optimization Challenges
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Experimental and numerical simulation study of the effect for the anode positions on the discharge characteristics of 300W class low power Hall thrusters
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作者 陈新伟 高俊 +5 位作者 杨三祥 耿海 郭宁 顾左 杨俊泰 张宏 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第1期100-110,共11页
Low-power Hall thruster(LHT) generally has poor discharge efficiency characteristics due to the large surface-to-volume ratio.Aiming to further refine and improve the performance of 300 W class LHT in terms of thrust ... Low-power Hall thruster(LHT) generally has poor discharge efficiency characteristics due to the large surface-to-volume ratio.Aiming to further refine and improve the performance of 300 W class LHT in terms of thrust and efficiency,and to obtain the most optimal operating point,the experimental study of the discharge characteristics for three different anode positions was conducted under the operation of various discharge voltages(100-400 V) and anode mass flow rates(0.65 mg·s-1and 0.95 mg·s-1).The experimental results indicated that the thruster has the most excellent performance in terms of thrust and efficiency etc at a channel length of 27 mm for identical operating conditions.In addition,particle in cell simulations,employed to reveal the underlying physical mechanisms,show that the ionization and acceleration zone is pushed downwards towards the channel exit as the anode moves towards the exit.At the identical operating point,when the channel length is reduced from 32 to 27 mm,the ionization and acceleration zone moves towards the exit,and the parameters such as thrust and efficiency increase due to the high ionization rate,ion number density,and axial electric field.When the channel length is further moved to 24 mm,the parameters in terms of thrust(F) and efficiency(ηa) are reduced as a result of the decreasing ionization efficiency(ηm) and the larger plume divergence angle(α).In this paper,the results indicated that an optimum anode position(ΔL=27 mm) exists for the optimum performance. 展开更多
关键词 low-power Hall thruster discharge characteristics PIC-MCC simulation anode positions
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Cooling performance analysis of radiant panel at different positions 被引量:2
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作者 高志宏 刘晓华 江亿 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期364-367,共4页
The influence of the panel position on the cooling performance of a radiant panel is analyzed.The coupled simulation of convection and radiation is set up by a computational fluid dynamics(CFD)method.The simulations... The influence of the panel position on the cooling performance of a radiant panel is analyzed.The coupled simulation of convection and radiation is set up by a computational fluid dynamics(CFD)method.The simulations with different panel positions and different indoor heat sources are used to calculate the cooling capacity of the radiant panel and the indoor thermal environment.The simulation results are in good agreement with the experimental results.The results show that when the indoor heat source temperature is low,the convective heat flux is the main influence factor of the cooling capacity and the radiant panel should be placed on the wall or on the ceiling.Otherwise,when the indoor heat source temperature is high,the radiation heat flux is the main factor and the radiant panel should be placed as near to the heat sources as possible. 展开更多
关键词 radiant panel panel position cooling capacity
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Relationships between temperature-light meteorological factors and seedcotton biomass per boll at different boll positions 被引量:4
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作者 WU You ZHAO Wen-qing +3 位作者 MENG Ya-li WANG You-hua CHEN Bing-lin ZHOU Zhi-guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第6期1315-1326,共12页
Cotton growth and development are determined and influenced by cultivars, meteorological conditions, and management practices. The objective of this study was to quantify the optimum of temperature-light meteorologica... Cotton growth and development are determined and influenced by cultivars, meteorological conditions, and management practices. The objective of this study was to quantify the optimum of temperature-light meteorological factors for seedcotton biomass per boll with respect to boll positions. Field experiments were conducted using two cultivars of Kemian 1 and Sumian 15 with three planting dates of 25 April (mean daily temperature (MDT) was 28.0 and 25.4°C in 2010 and 2011, respectively), 25 May (MDT was 22.5 and 21.2°C in 2010 and 2011, respectively), and 10 Jun (MDT was 18.7 and 17.9°C in 2010 and 2011, respectively), and under three shading levels (crop relative light rates (CRLR) were 100, 80, and 60%) during 2010 and 2011 cotton boll development period (from anthesis to boll open stages). The main meteorological factors (temperature and light) affected seedcotton biomass per boll differently among different boll positions and cultivars. Mean daily radiation (MDR) affected seedcotton biomass per boll at all boll positions, except fruiting branch 2 (FB2) fruting node 1 (FN1). However, its influence was less than temperature factors, especially growing degree-days (GDD). Optimum mean daily maximum temperature (MDTmax) for seedcotton biomass per boll at FB11FN3 was 29.9-32.4°C, and the optimum MDR at aforementioned position was 15.8-17.5 MJ m-2. Definitely, these results can contribute to future cultural practices such as rational cultivars choice and distribution, simplifying field managements and mechanization to acquire more efficient and economical cotton management. 展开更多
关键词 cotton (Gossypium hirsutum L.) temperature-light meteorological factors seedcotton biomass per boll boll positions
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Fiber Migration and Distribution of Twist at Different Radial Positions of Rotor Yarn-by Hi-Scope Video Microscope System 被引量:5
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作者 王善元 CHEUNG H.W. +2 位作者 张宏伟 LO M.T. 卢明德 《Journal of Donghua University(English Edition)》 EI CAS 2002年第3期45-47,共3页
This paper describes systematic measurement of fiber migration and distribution pattern of twist at different radial positions of rotor spun yarn mixed tracer fiber by Hi-Scope Video Microscope System. The positions o... This paper describes systematic measurement of fiber migration and distribution pattern of twist at different radial positions of rotor spun yarn mixed tracer fiber by Hi-Scope Video Microscope System. The positions of tracer fibers were measured in three dimensions accurately, and the migration index and the twist distribution at different radial positions of rotor yarn were calculated and analyzed. This research result serves to provide useful references for further study on the structural mechanics of rotor spun yarn. 展开更多
关键词 rotor yarn fiber migration twist distribution at different radial positions.
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Using self-location to calibrate the errors of observer positions for source localization 被引量:2
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作者 Wanchun Li Wanyi Zhang Liping Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第2期194-202,共9页
The uncertainty of observers' positions can lead to significantly degrading in source localization accuracy. This pa-per proposes a method of using self-location for calibrating the positions of observer stations in ... The uncertainty of observers' positions can lead to significantly degrading in source localization accuracy. This pa-per proposes a method of using self-location for calibrating the positions of observer stations in source localization to reduce the errors of the observer positions and improve the accuracy of the source localization. The relative distance measurements of the two coordinative observers are used for the linear minimum mean square error (LMMSE) estimator. The results of computer si-mulations prove the feasibility and effectiveness of the proposed method. With the general estimation errors of observers' positions, the MSE of the source localization with self-location calibration, which is significantly lower than that without self-location calibra-tion, is approximating to the Cramer-Rao lower bound (CRLB). 展开更多
关键词 self-location errors of the observer positions linearminimum mean square error (LMMSE) estimator accuracy of thesource localization Cramer-Rao lower bound (CRLB).
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Influence of relative positions between RF coil and crucible on sapphire crystals by edge-defined film-fed growth(EFG) technique 被引量:1
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作者 吴小凤 姚正军 +4 位作者 裴广庆 罗西希 徐尚君 林玉划 杨红勤 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3731-3737,共7页
To obtain the stable temperature field required for growing sapphire crystals, the influence of relative positions between RF coil and crucible on the performances of sapphires produced by edge-defined film-fed growth... To obtain the stable temperature field required for growing sapphire crystals, the influence of relative positions between RF coil and crucible on the performances of sapphires produced by edge-defined film-fed growth(EFG) technique was investigated. For comparison, the crucible was located at the top(case A) and the middle(case B) of the RF coil, respectively. Furthermore, the lattice integrities were studied by the double-crystal X-ray diffraction, and the dislocations were observed under the optical microscope and atomic force microscope after corroding in molten KOH at 390 ℃. The crystals in case B exhibit better lattice integrity with smaller full width at half maximum of 29.13 rad·s, while the value in case A is 45.17 rad·s. The morphologies of dislocation etch pits in both cases show typical triangular symmetry with smooth surfaces. However, the dislocation density of 2.8×104 cm-2 in case B is only half of that in case A, and the distribution is more uniform, compared to the U-shaper in case A. 展开更多
关键词 sapphire single-crystal edge-defined film-fed growth two relative positions lattice integrity dislocations
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A Comparative Study of the Short-Term Efficacy of Laparoscopic Radical Resection of Right-Sided Colon Cancer with Two Different Surgeon Positions and Trocar Placements 被引量:1
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作者 Ziling Zheng Maocai Tang +2 位作者 Shouru Zhang Hao Sun Jingkun Shang 《Journal of Cancer Therapy》 2022年第3期105-116,共12页
Objective: To investigate the short-term efficacy of laparoscopic radical resection of right-sided colon cancer with two different surgeon positions and trocar placements. Methods: The data of 78 patients who underwen... Objective: To investigate the short-term efficacy of laparoscopic radical resection of right-sided colon cancer with two different surgeon positions and trocar placements. Methods: The data of 78 patients who underwent laparoscopic radical resection of right-sided colon cancer between January 2018 and August 2019 were retrospectively analysed. The surgical method was selected by the patients. The patients were divided into two groups according to the surgeons’ positioning habits and trocar placements. The group with the lead surgeon standing between the patient’s legs had 35 patients, and the group with the lead surgeon standing at the left side of the patient had 43 patients. The operation time, intraoperative blood loss, postoperative anal gas evacuation time, postoperative urinary catheter indwelling time, postoperative hospital stay, C-reactive protein (CRP) level on the first day after surgery, and postoperative pathological data and complications were compared between the two groups. Results: All patients underwent the laparoscopic radical resection of right-sided colon cancer, none converting to laparotomy. No significant difference (P > 0.05) in intraoperative blood loss (57.6 ± 21.3 ml vs 60.2 ± 35.3 ml), postoperative anal gas evacuation time (3.5 ± 1.1 d vs 3.8 ± 1.3 d), postoperative urinary catheter indwelling time (2.6 ± 1.3 d vs 2.4 ± 1.2 d), postoperative hospital stay (7.1 ± 1.8 d vs 7.5 ± 2.1 d), or CRP level on the first day after surgery (54.7 ± 9.6 mg/L vs 53.9 ± 8.2 mg/L) was detected between the two groups. The operation time was shorter in the group with the lead surgeon standing between the patient’s legs (185.2 ± 25.6 min vs 196.2 ±19.7 min) (P < 0.05). The two groups did not differ significantly in the tumour length (4.2 ± 1.3 cm vs 3.9 ± 1.5 cm), number of dissected lymph nodes (27.5 ± 11.6 vs 25.1 ± 15.4), pathological type, or postoperative pathological tumour-node-metastasis stage (P > 0.05). No patients died or had anastomotic fistula during their postoperative hospital stay, and the incidence of postoperative complications did not differ between the two groups (22.9% (8/35) vs 23.3% (10/42);P > 0.05). Conclusion: Under the principle of radical resection, the surgeon should adopt the most suitable standing position and trocar placement according to the specific situation. If the surgeon stands between the patient’s legs, this might shorten the operation time and promote a smoother surgery. 展开更多
关键词 Laparoscopic Radical Resection Right-Sided Colon Cancer Surgeon positions Trocar Placements
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The Positions and Number of Flux Loops and Magnetic Probes for the HT-7U Superconducting Tokamak
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作者 沈飙 罗家融 +1 位作者 万宝年 王华中 《Plasma Science and Technology》 SCIE EI CAS CSCD 2003年第3期1785-1794,共10页
The plasma shape and other paremeters such as /3P, li is important for the tokamak deveice where the plasma has a non-circular cross-section of sufficient elongation. The measuered signals of magnetic probes and flux ... The plasma shape and other paremeters such as /3P, li is important for the tokamak deveice where the plasma has a non-circular cross-section of sufficient elongation. The measuered signals of magnetic probes and flux loops are used to reconstruct the plasma shape and the current profile in device operation and plasma shape feed back control system. So the number and positions of magnetic probes and flux loops provides the basis of the plasma reconstruction. This paper instroduce how to use EFIT code (equilibrium fitting code) to determine the number and positions of the magnetic probes and flux loops. The simulation result is given also. 展开更多
关键词 equilibrium reconstruction EFIT code positions and number magnetic probes and flux loops
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MODELLING THE POLYALANINE BACKBONE STARTING FROM ALPHA-CARBON GUIDE POSITIONS
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作者 Yu LUO Xu Liang JIANG Lu Hua LAI Chun Xu QU Xiao Jie XU You Qi TANG Institute of Physical Chemistry,Peking University,Beijing 100871 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第1期87-90,共4页
An automatic procedure for building a protein polyalanine backbone from guiding alpha-carbon positions is presented here,which is different from a previously developed'spare parts'approach(Jones and Thirup,198... An automatic procedure for building a protein polyalanine backbone from guiding alpha-carbon positions is presented here,which is different from a previously developed'spare parts'approach(Jones and Thirup,1986;Claessens et al.,1989). In our procedure,the geometric restraint of angle N-CA-C is used to generate a list of polypeptide chains,and several filters are used later to select the best conformer.The most important filter is based upon the Ramachandran scatter plot of mainchain dihedral angles PHI and PSI.Results for all test cases are satisfactory,with more than 95%of peptide planes correctly reconstructed and the overall root-mean-square deviation less than 0.5 angstrom compared with the refined X-ray coordinates. 展开更多
关键词 Bank MODELLING THE POLYALANINE BACKBONE STARTING FROM ALPHA-CARBON GUIDE positions length maps
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Studies on the Total Synthesis of Hainanolide(Ⅳ)-Revising the Stereochemistry of C_(2α)-H and Introducing the Two Hydroxy Groups at C_(3β),C_(4α) Positions
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作者 Wen Qian YANG Xiao Ming YU +1 位作者 Shi Zhi CHEN Liang HUANG(Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College,Beijing, 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,共2页
Tricyclic compound 6 was synthesized form compound 1 through sis steps, thus preblem of the stereochemistry of C2α-H being solved. The stereochemistry for introducing hydroxy groups at C3β and C4α positions in com... Tricyclic compound 6 was synthesized form compound 1 through sis steps, thus preblem of the stereochemistry of C2α-H being solved. The stereochemistry for introducing hydroxy groups at C3β and C4α positions in compound 1 was also described. 展开更多
关键词 Studies on the Total Synthesis of Hainanolide positions Revising the Stereochemistry of C H and Introducing the Two Hydroxy Groups at C
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Study on Element Contents in Tobacco Leaves from Different Positions of Tobacco CB-1
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作者 Caijun XIE Shilei ZHANG +9 位作者 Deqing CHEN Penghui LYU Wensheng LIN Jianrong ZHENG Jinchai YU Qiuying CAO Siyi CHENG Xueqin ZHANG Yongxin FENG Zenghan XU 《Agricultural Biotechnology》 CAS 2022年第6期119-125,共7页
[Objectives]This study was conducted to clarify the differences and abundance or deficiency of various elements in tobacco leaves from different positions of CB-1 in Zhangping City,so as to guide the production of pre... [Objectives]This study was conducted to clarify the differences and abundance or deficiency of various elements in tobacco leaves from different positions of CB-1 in Zhangping City,so as to guide the production of precision fertilization.[Methods]The element contents of CB-1 were determined by an X-ray fluorescence spectrometer.[Results]In terms of the contents of carbon,the upper leaves(45.73%)were significantly higher than the cutters(41.53%),and the lower leaves(43.15%)had no significant differences from both of them.For the content of oxygen element,there was no significant difference between the cutters(44.77%)and the lower leaves(43.40%),both of which were significantly higher than the upper leaves(40.75%).The contents of nitrogen,phosphorus,sulfur,boron and nickel all increased with the increase of the position,and they were significantly higher in the upper leaves than in the cutters and lower leaves.The contents of potassium,calcium,magnesium,chlorine and silicon all decreased with the increase of the position,and the lower leaves were significantly higher than the cutters and upper leaves.The contents of aluminum,titanium and chromium increased significantly with the increase of the position.The contents of strontium,zirconium and arsenic decreased significantly with the increase of the position.The element contents of tobacco leaves had significant or extremely significant differences between different parts of CB-1 in Zhangping City mostly.The contents of nitrogen,potassium,calcium,sulfur,chlorine,molybdenum and nickel in tobacco leaves were appropriate,and the contents of manganese and iron were too high,while the contents of phosphorus and copper were slightly low.The contents of magnesium,silicon,boron and sodium were too low.[Conclusions]This study can guide targeted fertilization and regulation of element contents in the tobacco leaves from different parts in production,and is of great significance to improving the production,quality and industrial availability of CB-1. 展开更多
关键词 CB-1 positions Lower leaf Cutters Upper leaf Nutrition element
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The Effect of Unloading Positions and Times on Sheet Metal’s Stress-Strain Curve
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作者 Kunmin Zhao Wumei Fang +1 位作者 Baotang Wang Daxin Ren 《Journal of Minerals and Materials Characterization and Engineering》 2018年第3期408-423,共16页
The loading-unloading-reloading process could affect the tensile deformation of metals with the combined function of stress relaxation and work hardening, which has been reported in multiple experiments. Nevertheless,... The loading-unloading-reloading process could affect the tensile deformation of metals with the combined function of stress relaxation and work hardening, which has been reported in multiple experiments. Nevertheless, the effects of different unloading positions and unloading times have not been investigated. In this study, unloading-reloading tests on three materials (AL6061, HSLA and Q195) were conducted. The stress exhibits a rapid rise momentarily upon reloading and stabilizes afterward while the post stress-strain curve deviates up or down from the monotonic tensile curve. The ductility is enhanced by the unloading-reloading process in general. Different unloading positions and unloading times have different degrees of influence on the stretching of these metals. The effect of loading conditions on a medium manganese steel was further studied. The functions to modify the post stress-strain relationship after unloading-reloading were established. 展开更多
关键词 Sheet Metal STRETCH Forming UNLOADING positions and TIMES ELONGATION STRESS-STRAIN
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Positions Open in the Field of Plasma and Fusion
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《Plasma Science and Technology》 SCIE EI CAS CSCD 2004年第3期i001-i001,共1页
Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important Laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is sear... Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important Laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is searching for 5 senior and 10 junior scientists of plasma and fusion in the following superconducting tokamak research areas: theory and simulation, diverter and edge physics, plasma diagnostics, electron cyclotron resonant heating, ion cyclotron resonant heating, lower hybrid wave, neutral beam injection, reactor design, fusion material, superconducting engineering. 展开更多
关键词 OPEN positions Open in the Field of Plasma and Fusion
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Positions Open in the Field of Plasma and Fusion
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《Plasma Science and Technology》 SCIE EI CAS CSCD 2004年第5期i001-i001,共1页
Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is sear... Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is searching for 5 senior and 10 junior scientists of plasma and fusion in the following superconducting tokamak research areas: theory and simulation, diverter and edge physics, plasma diagnostics, electron cyclotron resonant heating, ion cyclotron resonant heating, lower hybrid wave, neutral beam injection, reactor design, fusion material, superconducting engineering. 展开更多
关键词 positions Open in the Field of Plasma and Fusion OPEN
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Positions Open in the Field of Plasma and Fusion
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《Plasma Science and Technology》 SCIE EI CAS CSCD 2004年第6期i004-i004,共1页
Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is sear... Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is searching for 5 senior and 10 junior scientists of plasma and fusion in the following superconducting tokamak research areas: theory and simulation, diverter and edge physics, plasma diagnostics, electron cyclotron resonant heating, ion cyclotron resonant heating, lower hybrid wave, neutral beam injection, reactor design, fusion material, superconducting engineering. 展开更多
关键词 OPEN positions Open in the Field of Plasma and Fusion
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A User Proprietary Obfuscate System for Positions Sharing in Location-Aware Social Networks
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作者 Wei Cherng Cheng Masayoshi Aritsugi 《Journal of Computer and Communications》 2015年第5期7-20,共14页
A user’s trajectory can be maliciously monitored by adversaries when they share the positions in location-aware social networking applications which require users to update their own locations continuously. An advers... A user’s trajectory can be maliciously monitored by adversaries when they share the positions in location-aware social networking applications which require users to update their own locations continuously. An adversary infers user’s locations from the trajectories, and gleans user’s private information through them via location-aware social networking applications and public available geographic data. In this paper, we propose a user proprietary obfuscate system to suit situations for position sharing and location privacy preserving in location-aware social network. Users transform the public available geographic data into personal obfuscate region maps with pre-defined profile to prevent the location leaking in stationary status. Our obfuscation with size restricted regions method tunes user’s transformed locations fitting into natural movement and prevents unreasonable snapshot locations been recorded in the trajectory. 展开更多
关键词 Location PRIVACY Obfuscate Region Maps LOCATION-AWARE positions SHARING
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An adaptive routing protocol based on relative positions in VANETs
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作者 Wang Lei Yang Yang +2 位作者 Wang Xiaobo Ibrahima Kalil Toure Mi Zhenqiang 《High Technology Letters》 EI CAS 2012年第1期13-19,共7页
After presenting weaknesses of several classic routing protocols applied in vehicular ad hoc networks (VANETs) by a qualitative comparison, this paper proposes a novel self-adaptive routing protocol, named ARPP. Wit... After presenting weaknesses of several classic routing protocols applied in vehicular ad hoc networks (VANETs) by a qualitative comparison, this paper proposes a novel self-adaptive routing protocol, named ARPP. With respect to the specific characteristics of VANETs, the proposed routing protocol adopts a dynamic topology establishment and time-varying control message sending mechanism. A direction-based forwarding strategy and a specific warning solution enhance the routing performance in ARPP. Simulation results show that the ARPP protocol outperforms the classic AODV in urban vehicle environment. 展开更多
关键词 vehicular ad hoc networks(VANETs) routing protocol relative positions self-adaptivemechanism
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China’s Participation in Middle East Security Affairs in the New Era: Propositions and Practices
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作者 Sun Degang Wu Sike 《China International Studies》 2020年第5期37-64,共28页
espite their differences in political system,ideology and economic size,China and Middle East countries have sympathized with and supported each other in the international community.After the founding of New China,Ch... espite their differences in political system,ideology and economic size,China and Middle East countries have sympathized with and supported each other in the international community.After the founding of New China,China’s participation in Middle East security affairs can be broadly divided into three phases.During the first phase,from 1949 to 1979,China,proceeding from the ideological struggle against imperialism,colonialism,and great-power chauvinism,gave firm support to the national liberation movement in the Middle East as well as the Palestinian people’s just cause.During the second phase,from 1979 to 2012,on hotspot issues like the Iran-Iraq War,the Gulf War,the Palestinian-Israeli conflict and the Darfur issue,China,in light of the principle of“participating with caution and within one’s capabilities,”participated in Middle East security affairs on a selective basis.The third phase started from the 18th National Congress of the Communist Party of China(CPC)in 2012.China’s participation in Middle East security affairs has since shifted from“making a difference”to“actively making contributions,”with the building of a community with a shared future for mankind as its goal,the provision of security public goods as its means,and comprehensive security governance as its path.By doing so。 展开更多
关键词 MIDDLE positions FOUNDING
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Equilibrium Positions of a Cable-Connected Satellites System under Several Influences
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作者 Santosh Kumar Sangam Kumar 《International Journal of Astronomy and Astrophysics》 2016年第3期288-292,共6页
The present paper deals with the study of equilibrium positions of the motion of a system of two artificial satellites connected by a light, flexible, inextensible and non-conducting cable under the influence of solar... The present paper deals with the study of equilibrium positions of the motion of a system of two artificial satellites connected by a light, flexible, inextensible and non-conducting cable under the influence of solar radiation pressure, earth’s oblateness, shadow of the earth and air resistance. Here, we study the case of circular orbit of the centre of mass of the system. We derive differential equations of motion of the system. General solutions of the differential equations are beyond the reach. On the other hand, the general solutions do not serve our purpose. Jacobian integral of the system has also been obtained. Thereafter equilibrium positions of the motion of the system have been obtained. 展开更多
关键词 Equilibrium positions Two Cable-Connected Satellites Circular Orbit
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