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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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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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Changes in Cooking and Nutrition Qualities of Grains at Different Positions in a Rice Panicle under Different Nitrogen Levels 被引量:15
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作者 DONG Ming-hui SANG Da-zhi WANG Peng WANG Xue-ming YANG Jian-chang 《Rice science》 SCIE 2007年第2期141-148,共8页
Cooking and nutrition qualities of grain are two of the most important aspects of rice quality. To understand the difference in cooking and nutrition qualities among the grains at different positions within a rice pan... Cooking and nutrition qualities of grain are two of the most important aspects of rice quality. To understand the difference in cooking and nutrition qualities among the grains at different positions within a rice panicle, the distributions of gel consistency (GC), amylose content (AC) and crude protein content (CPC) of grains in a panicle in association with different nitrogen levels (0, 120 and 240 k c/ha) were investigated by using two rice varieties, Yangdao 6 (indica) and Wuyujing 3 (japonica). In general, the grains at the basal part of a panicle had lower GC and higher AC than those at the upper or middle part of a panicle. The 1^st grain on the secondary branch with earlier flowering exhibited the highest GC, whereas the 2nd grain on the primary branch with later flowering showed the highest AC. For Yangdao 6, CPC in the grains on the primary branches was lower at the middle part of a panicle than at the upper or basal part of a panicle. For Wuyujing 3, there were no significant differences in CPCs in the grains among the upper, middle and basal parts of a panicle. GC in the grains was increased, whereas AC was reduced from zero nitrogen application (ON) to low amount of nitrogen application (LN), and the result was reversed from LN to medium amount of nitrogen application (MN). CPC was increased with the increase in the amount of nitrogen application. 展开更多
关键词 RICE grain position cooking quality nutrition quality NITROGEN
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Prevention of aspiration of gastric contents during attempt in tracheal intubation in the semi-lateral and lateral positions 被引量:7
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作者 Ichiro Takenaka Kazuyoshi Aoyama 《World Journal of Emergency Medicine》 CAS 2016年第4期285-289,共5页
BACKGROUND:Pulmonary aspiration of gastric contents during tracheal intubation is a lifethreatening complication in emergency patients.Rapid sequence intubation is commonly performed to prevent aspiration but is not a... BACKGROUND:Pulmonary aspiration of gastric contents during tracheal intubation is a lifethreatening complication in emergency patients.Rapid sequence intubation is commonly performed to prevent aspiration but is not associated with low risk of intubation related complications.Although it has been considered that aspiration can be prevented in the lateral position,few studies have evaluated the ability to prevent aspiration.Moreover,this position is not always a favorable position for tracheal intubation.If aspiration can be prevented in a clinically relevant semi-lateral position,it may be advantageous.We assessed the ability to prevent aspiration in the lateral position and various degrees of the semi-lateral position using a vomiting-regurgitation manikin model.METHODS:A manikin's head was placed in the neutral,simple extension,or sniffing position.The amount of aspirated saline into the bronchi during simulated vomiting was measured at semilateral position angles of 0°to 90° in 10° increments.The difference in the vertical height between the mouth corner and the inferior border of the vocal cord was measured radiologically at each semilateral position in the three head-neck positions.RESULTS:Pulmonary aspiration was prevented at the ≥70°,≥80°,and 90° semi-lateral positions in the neutral,simple extension,and sniffing positions,respectively.The mouth was lower than the vocal cord in the semi-lateral position in which aspiration was prevented.CONCLUSION:The lateral or excessive semi-lateral position was necessary to protect the lung from aspiration in the head-neck positions commonly used for tracheal intubation.Prevention of aspiration was difficult within clinically relevant semi-lateral positions. 展开更多
关键词 Pulmonary aspiration Lateral position Semi-lateral position
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Systematic positions of Lamiophlomis and Paraphlomis(Lamiaceae) based on nuclear and chloroplast sequences 被引量:4
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作者 Yue-Zhi PAN Li-Qin FANG +2 位作者 Gang HAO Jie CAI Xun GONG 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第6期535-542,共8页
Genera Lamiophlomis and Paraphlomis were originally separated from genus Phlomis s.1. on the basis of particular morphological characteristics. However, their relationship was highly contentious, as evidenced by the l... Genera Lamiophlomis and Paraphlomis were originally separated from genus Phlomis s.1. on the basis of particular morphological characteristics. However, their relationship was highly contentious, as evidenced by the literature. In the present paper, the systematic positions of Lamiophlomis, Paraphlomis, and their related genera were assessed based on nuclear internal transcribed spacer (ITS) and chloroplast rpl16 and trnL-F sequence data using maximum parsimony (MP) and Bayesian methods. and outgroup were sampled. Analyses of both separate In total, 24 species representing six genera of the ingroup and combined sequence data were conducted to resolve the systematic relationships of these genera. The results reveal that Lamiophlomis is nested within Phlomis sect. Phlomoides and its generic status is not supported. With the inclusion ofLamiophlomis rotata in sect. Phlomoides, sections Phlomis and Phlomoides of Phlomis were resolved as monophyletic. Paraphlomis was supported as an independent genus. However, the resolution of its monophyly conflicted between MP and Bayesian analyses, suggesting the need for expended sampling and further evidence. 展开更多
关键词 internal transcribed spacer (ITS) Lamiophlomis Paraphlomis rpl 16 systematic position trnL-F.
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Nucleosome Positions and Differential Methylation Status of Various Regions within MLH1 CpG Island 被引量:2
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作者 白桦 周静 邓大君 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2008年第4期237-242,共6页
Objective: To determine the relationship between nucleosome positions and formation of differential methylation of the reported region A, B, C, and D within the MLH1 CpG island. Methods: Methylation of the MLH1 prom... Objective: To determine the relationship between nucleosome positions and formation of differential methylation of the reported region A, B, C, and D within the MLH1 CpG island. Methods: Methylation of the MLH1 promoter was analyzed by combined of bisulfite restriction assay. Chromatin of RKO and MGC803 cells were extracted and digested by MNase. Mononucleosomal DNA fragment was isolated and used as templates for detection of nucleosomal distribution by a battery of quantitative PCRs covering the full MLH1 promoter region. Results: The MLH1 was methylated in RKO and unmethylated in MGC803. At the region B, where methylation of CpG sites did not correlated with transcription of this gene well, qPCR product of the M-3 (-599nt ~ -475nt) fragment was amplified in both RKO and MGC803 cells. However, at the region C and D within the core promoter, where methylation of CpG sites correlated with loss of MLH1 transcription well, the M-7 (-257nt ~ -153nt) and M-8 (-189nt ~ -71nt) fragments were amplified remarkably only in RKO cells. Conclusion: Nucleosome may be the basic unit for both CpG methylation and methylation-related regulation of gene transcription. Methylation status of CpG sites within the same nucleosome may be homogeneous; between different nucleosomes, homogeneous or heterogeneous. 展开更多
关键词 Nucleosome position METHYLATION MLHI CpG Island
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Characteristics of soil seed banks at different geomorphic positions within the longitudinal sand dunes of the Gurbantunggut Desert, China 被引量:4
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作者 JIA Fengqin Tashpolat TIYIP +2 位作者 WU Nan TIAN Changyan ZHANG Yuanming 《Journal of Arid Land》 SCIE CSCD 2017年第3期355-367,共13页
Understanding the characteristics of soil seed banks in sand dunes is crucial to stabilize the dune systems and maintain the plant populations in deserts. In this study, we conducted a survey investigation in the fiel... Understanding the characteristics of soil seed banks in sand dunes is crucial to stabilize the dune systems and maintain the plant populations in deserts. In this study, we conducted a survey investigation in the field and a seed germination experiment in the laboratory to explore the characteristics of soil seed banks at various geomorphic positions of longitudinal sand dunes in the Gurbantunggut Desert, China. Totally, 17 plant species belonging to 17 genera and 9 families were identified in soil seed banks, and 35 plant species belonging to 34 genera and 17 families were identified in aboveground vegetation. Plant species richness in soil seed banks decreased with increasing soil depth. The highest species richness was presented in the upper slope of the windward slope and the lowest species richness was presented in the base of the windward slope. There was no significant difference in seed density of soil seed banks among the examined seven geomorphic positions. The highest seed density occurred in the lower slope of the leeward slope while the lowest occurred in the crest. Moreover, seed density decreased with increasing soil depth, being the highest in the upper soil layer (0-2 cm). For both soil seed banks and aboveground vegetation, there was no significant difference in Simpson's diversity index among the seven geomorphic positions; however, Shannon-Wiener diversity index and Pielou's evenness index showed significant differences among the seven geomorphic positions. Those results showed that although there was no significant difference in seed density of soil seed banks among the seven geomorphic positions, the geomorphic positions significantly affected the species richness, diversity and distribution of soil seed banks. Therefore, understanding the characteristics of soil seed banks at different geomorphic positions of sand dunes is essential to vegetation restoration or reestablishment. Furthermore, the Jaccard's similarity coefficients of plant species between soil seed banks and aboveground vegetation at the seven geomorphic positions were low, suggesting that vegetation restoration or reestablishment processes should be promoted through adding seeds to surface layers. 展开更多
关键词 soil seed banks geomorphic position seed density species diversity sand dunes Gurbantunggut Desert
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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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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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Three-dimensional positions of scattering centers reconstruction from multiple SAR images based on radargrammetry 被引量:3
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作者 钟金荣 文贡坚 +1 位作者 回丙伟 李德仁 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1776-1789,共14页
A method and procedure is presented to reconstruct three-dimensional(3D) positions of scattering centers from multiple synthetic aperture radar(SAR) images. Firstly, two-dimensional(2D) attribute scattering centers of... A method and procedure is presented to reconstruct three-dimensional(3D) positions of scattering centers from multiple synthetic aperture radar(SAR) images. Firstly, two-dimensional(2D) attribute scattering centers of targets are extracted from 2D SAR images. Secondly, similarity measure is developed based on 2D attributed scatter centers' location, type, and radargrammetry principle between multiple SAR images. By this similarity, we can associate 2D scatter centers and then obtain candidate 3D scattering centers. Thirdly, these candidate scattering centers are clustered in 3D space to reconstruct final 3D positions. Compared with presented methods, the proposed method has a capability of describing distributed scattering center, reduces false and missing 3D scattering centers, and has fewer restrictionson modeling data. Finally, results of experiments have demonstrated the effectiveness of the proposed method. 展开更多
关键词 multiple synthetic aperture radar(SAR) images three-dimensional scattering center position reconstruction radargrammetry
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Kappa angles in different positions in patients with myopia during LASIK 被引量:6
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作者 Hui Qi Jing-Jing Jiang +2 位作者 Yan-Ming Jiang Li-Qiang Wang Yi-Fei Huang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第4期585-589,共5页
AIM: To investigate the difference in kappa angle between sitting and supine positions during laser-assisted in situ keratomileusis(LASIK).·METHODS: A retrospective study was performed on395 eyes from 215 pat... AIM: To investigate the difference in kappa angle between sitting and supine positions during laser-assisted in situ keratomileusis(LASIK).·METHODS: A retrospective study was performed on395 eyes from 215 patients with myopia that received LASIK. Low, moderate, and high myopia groups were assigned according to diopters. The horizontal and vertical components of kappa angle in sitting position were measured before the operation, and in supine position during the operation. The data from the two positions were compared and the relationship between kappa angle and diopters were analyzed.· RESULTS: Two hundred and twenty-three eyes(56.5%) in sitting position and 343 eyes(86.8%) in supine position had positive kappa angles. There were no significant differences in horizontal and vertical components of kappa angle in the sitting position or horizontal components of kappa angle in the supine position between the three groups(P 〉0.05). A significant difference in the vertical components of kappa angle in the supine position was seen in the three groups(P 〈0.01). Differences in both horizontal and vertical components of kappa angles were significant between the sitting and supine positions. Positive correlations in both horizontal and vertical components of kappa angles(P 〈0.05) were found and vertical components of kappa angle in sitting and supine positions were negatively correlated with the degree of myopia(sitting position: r =-0.109; supine position: r =-0.172; P 〈0.05).·CONCLUSION: There is a correlation in horizontal and vertical components of kappa angle in sitting and supine positions. Positive correlations in both horizontal and vertical components of kappa angle in sitting and supine positions till the end of the results. This result still needs further observation. Clinicians should take into account different postures when excimer laser surgery needs to be performed. 展开更多
关键词 kappa angle myopia keratomileusis laser in situ supine position
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The effects of sowing date on cottonseed properties at different fruiting-branch positions 被引量:1
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作者 HU Wei CHEN Mei-li +5 位作者 ZHAO Wen-qing CHEN Bing-lin WANG You-hua WANG Shan-shan MENG Ya-li ZHOU Zhi-guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第6期1322-1330,共9页
A two-year field experiment was conducted to illustrate the effects of sowing date on cottonseed properties at different fruiting-branch positions(FBPs).Two cotton cultivars(Kemian 1 and Sumian 15)were sowed on 25... A two-year field experiment was conducted to illustrate the effects of sowing date on cottonseed properties at different fruiting-branch positions(FBPs).Two cotton cultivars(Kemian 1 and Sumian 15)were sowed on 25 April,25 May,and10 June in 2010 and 2011,respectively.The boll maturation period increased with the delaying of sowing date.Normal sowing treatment(25 April)had higher seed weight,embryo weight,embryo oil content and protein content than late sowing treatments(25 May and 10 June).The flowering date,seed weight,embryo weight,embryo oil and protein contents,and the dynamic changes of embryo oil and protein contents were altered by different FBPs.A significant interaction of sowing date×FBP was observed on embryo weight,embryo oil content,embryo protein content and the dynamic changes of embryo oil and protein contents,but was not observed on seed weight.Seed weight,embryo weight,embryo oil and protein content had significant positive correlations with the mean daily temperature(MDT),mean daily maximum temperature(MDTmax),mean daily minimum temperature(MDTmin),and mean daily solar radiation(MDSR),indicating that temperature and light resources were the main reasons for different sowing dates affecting the cottonseed properties at different FBPs.Moreover,the difference in MDT was the main difference in climatic factors among different sowing dates. 展开更多
关键词 sowing date fruiting-branch position cottonseed properties
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Variations in Carbohydrate and Protein Accumulation among Spikelets at Different Positions Within a Panicle During Rice Grain Filling 被引量:2
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作者 DONG Ming-hui CHEN Pei-feng +2 位作者 XIE Yu-lin QIAO Zhong-ying YANG Jian-chang 《Rice science》 2012年第3期223-232,共10页
The accumulation dynamics of kernel components for spikelets at different positions within a rice panicle were investigated during grain filling to understand the physiological reasons for the variation of grain quali... The accumulation dynamics of kernel components for spikelets at different positions within a rice panicle were investigated during grain filling to understand the physiological reasons for the variation of grain quality.Two rice cultivars,Yangdao 6 (indica) and Yangjing 9538 (japonica),were field-grown,and the grain filling characters and contents of starch,soluble sugar,and protein of the spikelets at different positions were studied.There were significant differences in matter accumulation among spikelets at different positions during grain filling.The early-flowering spikelets presented dominance over the late-flowering spikelets in initial time and initial rate of accumulation.At the initial and mid filling stages,the contents and the rates of starch and amylose accumulation in spikelets decreased with the flowering sequence,but soluble sugar content (SSC) exhibited the opposite trend.The difference in SSC among the spikelets of Yangjing 9538 was greater than that of Yangdao 6,but amylose content in mature spikelets showed no obvious relationship to their flowering sequence.The crude protein content (CPC) of early-flowering spikelets decreased more rapidly than that of late-flowering ones at the initial filling stage,and CPC in the spikelets on the secondary branch was higher than that on the primary branch,but CPC in early-flowering ones was lower than that in late-flowering across the whole grain filling period.Grain water content (GWC) of early-flowering spikelets decreased more rapidly than that of late-flowering spikelets on the same branch at the initial and mid filling stages,especially for the top grain on each primary branch.The results suggested that poor grain filling of late-flowering spikelets may be attributed to their low biological activity rather than carbohydrate supply limitation. 展开更多
关键词 spikelet position STARCH protein accumulation dynamic variation rice grain filling
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Kinematic Geometry for the Saddle Line Fitting of Planar Discrete Positions 被引量:1
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作者 WU Yu WANG Delun +2 位作者 WANG Wei YU Shudong XU Wenji 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第4期763-768,共6页
The position synthesis of planar linkages is to locate the center point of the moving joint on a rigid link, whose trajectory is a circle or a straight line. Utilizing the min-max optimization scheme, the fitting curv... The position synthesis of planar linkages is to locate the center point of the moving joint on a rigid link, whose trajectory is a circle or a straight line. Utilizing the min-max optimization scheme, the fitting curve needs to minimize the maximum fitting error to acquire the dimension of a planar binary P-R link. Based on the saddle point programming, the fitting straight line is determined to the planar discrete point-path traced by the point of the rigid body in planar motion. The property and evolution of the defined saddle line error can be revealed from three given separate points. A quartic algebraic equation relating the fitting error and the coordinates is derived, which agrees with the classical theory. The effect of the fourth point is discussed in three cases through the constraint equations. The multi-position saddle line error is obtained by combination and comparison from the saddle point programming. Several examples are presented to illustrate the solution process for the saddle line error of the moving plane. The saddle line error surface and the contour map presented to show the variations of the fitting error in the fixed frame. The discrete kinematic geometry is then set up to disclose the relations of the separate positions of the rigid body, the location of the tracing point on the moving body, and the position and orientation of the saddle line to the point-path. This paper presents a new analytic geometry method for saddle line fitting and provides a theoretical foundation for position synthesis. 展开更多
关键词 saddle point programming kinematic geometry saddle line error position synthesis
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Hip External Rotator Strength and Compensatory Movement in Three Different Positions 被引量:1
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作者 Sun-Hee Ahn Ui-Jae Hwang +3 位作者 Sung-Hoon Jung Hyun-A Kim Jun-Hee Kim Oh-Yun Kwon 《Health》 2018年第1期132-144,共13页
Measuring intrinsic hip external rotator strength (ER) without compensatory pelvic motion and activation of the sartorius is important for preventing or rehabilitating lower extremity injuries. However, the optimal me... Measuring intrinsic hip external rotator strength (ER) without compensatory pelvic motion and activation of the sartorius is important for preventing or rehabilitating lower extremity injuries. However, the optimal method for measuring intrinsic hip ER muscle strength while minimizing compensatory pelvic motions and activation of the sartorius is unclear. The purpose of this study is to compare measurements of hip ER strength, compensatory pelvic motion, and sartorius activation in the sitting, prone, and sidelying positions. Thirty-one healthy subjects (16 males and 15 females) were recruited for this study. Hip ER strength, pelvic kinematics, and sartorius muscle activation were measured during maximal isometric contraction of the hip ER in the sitting, prone, and sidelying positions. Hip ER strength was measured using a load-cell-type strength-measurement sensor. Pelvic kinematics was measured using an electromagnetic motion-tracking sensor. Electromyography was used to measure sartorius muscle activity. Data were analyzed using one-way repeated-measures analysis of variance. The result showed that hip ER strength and sartorius muscle activation were significantly lower in the sidelying compared with the sitting and prone positions (p < 0.01). Pelvic anteroposterior tilting was significantly greater in the sitting compared with the prone and sidelying positions (p < 0.01). Pelvic rotation differed significantly among positions (p < 0.01). Pelvic lateral tilting was significantly greater in the prone compared with the sitting position (p < 0.017). Compensatory pelvic motion and sartorius muscle activation were lower when hip ER strength measurements were made in the sidelying position. Therefore, the sidelying position is effective for measuring selective intrinsic hip ER strength. 展开更多
关键词 COMPENSATORY PELVIC Motion HIP EXTERNAL ROTATOR Measurement position SARTORIUS
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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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Spatial distribution of Pb and its correlation at different grain positions among wheat varieties for specific end-uses 被引量:1
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作者 Fei Xiong Zhaodi Dong +2 位作者 Xurun Yu Liang Zhou Zhong Wang 《Agricultural Sciences》 2013年第9期509-515,共7页
The relative content of Pb and its correlation were investigated in endosperm, aleurone layer and pericarp respectively among different wheat varieties for specific end-uses (WVFSE) using scanning electron microscope ... The relative content of Pb and its correlation were investigated in endosperm, aleurone layer and pericarp respectively among different wheat varieties for specific end-uses (WVFSE) using scanning electron microscope (SEM) equipped with the energy dispersive X-ray spectroscope (EDS). The results showed that Pb contents in grains at different positions followed the order of endosperm > pericarp > aleurone. The differences of Pb contents varied among the WVFSE, and wheat with strong gluten had a highest average content of Pb, while wheat with medium gluten had a lowest one. There were significant third order equation correlations between Pb content in endosperm and that in aleurone layer and that in pericarp, respectively. And good correlation coefficients were obtained. However, the correlation differed at different position among WVFSE, which indicated that Pb contents in endosperm, aleurone layer and pericarp were regulated by each other. 展开更多
关键词 Lead CORRELATION Wheat VARIETIES for SPECIFIC End-Uses Grain position
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Effects of planting dates and shading on carbohydrate content,yield,and fiber quality in cotton with respect to fruiting positions 被引量:2
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作者 ZHAO Wen-qing WU You +5 位作者 Zahoor Rizwan WANG You-hua MA Yi-na CHEN Bing-lin MENG Ya-li ZHOU Zhi-guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第5期1106-1119,共14页
Two cotton(Gossypium hirsutum L.) cultivars, Kemian 1(cool temperature-tolerant) and Sumian 15(cool temperaturesensitive) were used to study the effects of cool temperature on carbohydrates, yield, and fiber qua... Two cotton(Gossypium hirsutum L.) cultivars, Kemian 1(cool temperature-tolerant) and Sumian 15(cool temperaturesensitive) were used to study the effects of cool temperature on carbohydrates, yield, and fiber quality in cotton bolls located at different fruiting positions(FP). Cool temperatures were created using late planting and low light. The experiment was conducted in 2010 and 2011 using two planting dates(OPD, the optimized planting date, 25 April; LPD, the late planting date, 10 June) and two shading levels of crop relative light rate(CRLR, 100 and 60%). Compared with fruiting position 1(FP1), cotton yield and yield components(fiber quality, leaf sucrose and starch content, and fiber cellulose) were all decreased on FP3 under all treatments. Compared with OPD-CRLR 100%, other treatments(OPD-CRLR 60%, LPD-CRLR 100%, and LPD-CRLR 60%) had significantly decreased lint yield at both FPs of both cultivars, but especially at FP3 and in Sumian 15; this decrease was mainly caused by a large decline in boll number. All fiber quality indices decreased under late planting and shading except fiber length at FP1 with OPD-CRLR 60%, and a greater reduction was observed at FP3 and in Sumian 15. Sucrose content of the subtending leaf and fiber increased under LPD compared to OPD, whereas it decreased under CRLR 60% compared to CRLR 100%, which led to decreased fiber cellulose content. Therefore, shading primarily decreased the "source" sucrose content in the subtending leaf whereas late planting diminished translocation of sucrose towards cotton fiber. Notably, as planting date was delayed and light was decreased, more carbohydrates were distributed to leaf and bolls at FP1 than those at FP3, resulting in higher yield and better fiber quality at FP1, and a higher proportion of bolls and carbohydrates allocated at FP3 of Kemian 1 compared to that of Sumian 15. In conclusion, cotton yield and fiber quality were reduced less at FP1 compared to those at FP3 under low temperature and low light conditions. Thus, reduced cotton yield and fiber quality loss can be minimized by selecting low temperature tolerant cultivars under both low temperature and light conditions. 展开更多
关键词 cotton planting date and shading fruiting position yield fiber quality
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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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Numerical Investigation on the Secondary Flow Control by Using Splitters at Different Positions with Respect to the Main Blade 被引量:1
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作者 Tao Bian Xin Shen +1 位作者 Jun Feng Bing Wang 《Fluid Dynamics & Materials Processing》 EI 2021年第3期615-628,共14页
In turbomachinery,strong secondary flow can produce significant losses of total pressure near the endwall and reduce the efficiency of the considered turbomachine.In this study,splitters located at different positions... In turbomachinery,strong secondary flow can produce significant losses of total pressure near the endwall and reduce the efficiency of the considered turbomachine.In this study,splitters located at different positions with respect to the main blade have been used to reduce such losses and improve the efficiency of the outlet guide vane(OGV).Three different relative positions have been considered assuming a NACA 65-010 profile for both the main blade and the splitter.The numerical results indicate that splitters can effectively reduce the total pressure loss by suppressing the secondary flow around the main blade,but the splitters themselves also produce flow losses,which are caused by flow separation effects. 展开更多
关键词 Total pressure loss splitters relative position secondary flow guide vanes
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