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Differential distribution of PINK1 and Parkin in the primate brain implies distinct roles
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作者 Yanting Liu Wei Huang +8 位作者 Jiayi Wen Xin Xiong Ting Xu Qi Wang Xiusheng Chen Xianxian Zhao Shihua Li Xiaojiang Li Weili Yang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1124-1134,共11页
The vast majority of in vitro studies have demonstrated that PINK1 phosphorylates Parkin to work together in mitophagy to protect against neuronal degeneration.However,it remains largely unclear how PINK1 and Parkin a... The vast majority of in vitro studies have demonstrated that PINK1 phosphorylates Parkin to work together in mitophagy to protect against neuronal degeneration.However,it remains largely unclear how PINK1 and Parkin are expressed in mammalian brains.This has been difficult to address because of the intrinsically low levels of PINK1 and undetectable levels of phosphorylated Parkin in small animals.Understanding this issue is critical for elucidating the in vivo roles of PINK1 and Parkin.Recently,we showed that the PINK1 kinase is selectively expressed as a truncated form(PINK1–55)in the primate brain.In the present study,we used multiple antibodies,including our recently developed monoclonal anti-PINK1,to validate the selective expression of PINK1 in the primate brain.We found that PINK1 was stably expressed in the monkey brain at postnatal and adulthood stages,which is consistent with the findings that depleting PINK1 can cause neuronal loss in developing and adult monkey brains.PINK1 was enriched in the membrane-bound fractionations,whereas Parkin was soluble with a distinguishable distribution.Immunofluorescent double staining experiments showed that PINK1 and Parkin did not colocalize under physiological conditions in cultured monkey astrocytes,though they did colocalize on mitochondria when the cells were exposed to mitochondrial stress.These findings suggest that PINK1 and Parkin may have distinct roles beyond their well-known function in mitophagy during mitochondrial damage. 展开更多
关键词 NEURODEGENERATION PARKIN Parkinson’s disease PINK1 subcellular distribution
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Pore Size Distribution of High Performance Metakaolin Concrete 被引量:4
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作者 C.S.Poon S.C.Kou L.Lam 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2002年第1期42-46,共5页
The Compressive strength, porosity and pore size distribution of high performance metakaolin (MK) concrete were investigated. Concretes containing 0,5% , 10% and 20% metakaolin were prepared at a water / cementitious ... The Compressive strength, porosity and pore size distribution of high performance metakaolin (MK) concrete were investigated. Concretes containing 0,5% , 10% and 20% metakaolin were prepared at a water / cementitious material ratio ( W/C) of 0. 30. In parallel, concrete mixtures with the replacement of cement by 20% fly ash or 5 and 10% silica fume were prepared for comparison. The specimens were cured in water at 27℃ for 3 to 90 days. The results show that at the early age of curing (3 days and 7 days), metakaolin replacements increase the compressive strength, but silica fume replacement slightly reduces the compressive strength. At the age of and after 28 days , the compressive strength of the concrete with metakaolin and silica fume replacement increases. A strong reduction in the total porosity and average pore diameter were observed in the concrete with MK 20% and 10% in the first 7 days. 展开更多
关键词 high performance concrete METAKAOLIN pore size distribution
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Tuning Solid Interfaces via Varying Electrolyte Distributions Enables High-Performance Solid-State Batteries 被引量:1
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作者 Linfeng Peng Chuang Yu +5 位作者 Ziqi Zhang Ruonan Xu Mengjun Sun Long Zhang Shijie Cheng Jia Xie 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期26-33,共8页
Solid/solid interface is the major challenge for high-performance solid-state batteries.Solid electrolytes(SEs)play a crucial role in the fabrication of effective interfaces in solid-state batteries.Herein,the electro... Solid/solid interface is the major challenge for high-performance solid-state batteries.Solid electrolytes(SEs)play a crucial role in the fabrication of effective interfaces in solid-state batteries.Herein,the electrolyte distribution with varied particle sizes is tuned to construct solid-state batteries with excellent performance at different operating temperatures.Solid-state batteries with the configuration S/L(small-sized SE in composite cathode and large-sized SE in electrolyte layer)show the best performance at room temperature(168 mA h g^(−1) at 0.2 C,retention of 99%,100 cycles)and−20°C(89 mA h g^(−1) at 0.05 C),while the configuration S/S displays better performance at elevated temperature.The superior performance of S/L battery is associated with faster lithium-ion dynamics due to the better solid/solid interface between active materials and electrolytes.Moreover,the inferior performance at 60℃is caused by the formation of voids and cracks in the electrolyte layer during cycling.In contrast,the S/S battery delivers superior performance at elevated operating temperature because of the integrated structure.This work confirms that tailoring electrolyte size has significant effect on fabricating all-climate solid-state batteries. 展开更多
关键词 electrochemical performance lithium argyrodite operating temperature size distribution solid-state batteries
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Performance analysis of continuous-variable measurement-device-independent quantum key distribution under diverse weather conditions
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作者 Shu-Jing Zhang Chen Xiao +4 位作者 Chun Zhou Xiang Wang Jian-Shu Yao Hai-Long Zhang Wan-Su Bao 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第2期100-106,共7页
The effects of weather conditions are ubiquitous in practical wireless quantum communication links.Here in this work,the performances of atmospheric continuous-variable measurement-device-independent quantum key distr... The effects of weather conditions are ubiquitous in practical wireless quantum communication links.Here in this work,the performances of atmospheric continuous-variable measurement-device-independent quantum key distribution(CV-MDI-QKD)under diverse weather conditions are analyzed quantitatively.According to the Mie scattering theory and atmospheric CV-MDI-QKD model,we numerically simulate the relationship between performance of CV-MDI-QKD and the rainy and foggy conditions,aiming to get close to the actual combat environment in the future.The results show that both rain and fog will degrade the performance of the CV-MDI-QKD protocol.Under the rainy condition,the larger the raindrop diameter,the more obvious the extinction effect is and the lower the secret key rate accordingly.In addition,we find that the secret key rate decreases with the increase of spot deflection distance and the fluctuation of deflection.Under the foggy condition,the results illustrate that the transmittance decreases with the increase of droplet radius or deflection distance,which eventually yields the decrease in the secret key rate.Besides,in both weather conditions,the increase of transmission distance also leads the secret key rate to deteriorate.Our work can provide a foundation for evaluating the performance evaluation and successfully implementing the atmospheric CV-MDI-QKD in the future field operation environment under different weather conditions. 展开更多
关键词 weather conditions atmospheric continuous-variable measurement-device-independent quantum key distribution(CV-MDI-QKD) performance
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Thermal Distribution Performance of NPCM: NaCl, NaNO<sub>3</sub>and KNO<sub>3</sub>in the Thermal Storage System
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作者 Pises Tooklang Sarayooth Vaivudh +1 位作者 Sukrudee Sukchai Wattanapong Rakwichian 《Energy and Power Engineering》 2014年第7期174-185,共12页
The experiment is studied on thermal distribution in the thermal energy storage system with non-phase change materials (NPCM): NaNO3, KNO3 and NaCl in the range of 25°C - 250°C. The cylindrical storage syste... The experiment is studied on thermal distribution in the thermal energy storage system with non-phase change materials (NPCM): NaNO3, KNO3 and NaCl in the range of 25°C - 250°C. The cylindrical storage system was made of stainless steel with 25.6 cm-diameter and 26.8 cm-height that was contained of these NPCM. There was one pipe for heat transfer fluid (HTF) with 1.27 cm-diameter that manipulates in the storage tank and submerges to NPCM. The inner pipe was connected to the 2.27 cm-diameter outer HTF tube. The tube was further connected to the thermal pump, heater and load. The pump circulates the synthetic oil (Thermia oil) within the pipe for heat transferring purposes (charging and discharging). An electric heater is used as the heat source. The limitation of the charging oil temperature is maintained at 250°C with the flow rates in the range of 0.58 to 1.45 kg/s whereas the inlet temperature of the discharge oil is maintained at 25°C. Thermal performances of TES (thermal energy storage) such as charging and discharging times, radial thermal distribution, energy storage capacity and energy efficiency have been evaluated. The experimental results show that the radial thermal distribution of NaCl for TR inside, TR middle and TR outside was optimum of temperature down to NaNO3 and KNO3 respectively. Comparison of NPCMs with oil, flow rates for NaCl were charging and discharging heat transfer than KNO3 and NaNO3. The thermal stored NaCl ranged from 5712 - 5912 J;KNO3 ranged from 7350 - 7939 J and NaNO3 ranged from 6623 - 6930 J respectively. The thermal energy stored for experimental results got with along the KNO3, NaNO3 and NaCl respectively. The thermal energy efficiency of NaCl, KNO3 and NaNO3 was in the range 66% - 70%. 展开更多
关键词 THERMAL distribution Non-Phase Change Materials Heat Transfer Fluid THERMAL Energy storage THERMAL performance
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A Simple Statistical Estimation of One’s Performance in an MCQ Examination, Based Upon Mock Test Results, Using Binomial Distribution of Probability
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作者 Sudipto Roy Priyadarshi Majumdar 《Open Journal of Statistics》 2012年第4期452-459,共8页
A simple statistical model is proposed regarding the estimation of one’s overall performance in an MCQ examination along with the calculation of probability of obtaining a certain percentage of marks in the same. Usi... A simple statistical model is proposed regarding the estimation of one’s overall performance in an MCQ examination along with the calculation of probability of obtaining a certain percentage of marks in the same. Using the data obtained from the results of a sufficiently large number of mock examinations, conducted prior to the main examination, certain parameters quantifying one’s knowledge or preparation for the examination has been calculated. Based on those parameters, the probability of obtaining a certain percentage of marks has been computed using the theory of binomial probability distribution. The dependence of this probability function on various parameters has been depicted graphically. A parameter, called the performance index, has been defined in terms of the expectation value and standard deviation of marks computed from probability distribution. Using this parameter, a new parameter called the relative performance index has been defined. This index estimates one’s performance with respect to the best possible performance. The variation of relative performance index with respect to the preparation index has been shown graphically for different parameter values quantifying various aspects regarding the examination and the examinee. 展开更多
关键词 MCQ Preparation INDEX Knowledge INDEX Application INDEX performance INDEX Relative performance BINOMIAL PROBABILITY distribution Estimation of EXAMINATION Result
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Performance Appraisal Method of Logistic Distribution for Fresh Agricultural Products 被引量:2
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作者 YU Hang,ZHANG Kai Jilin Agricultural University,Changchun 130118,China 《Asian Agricultural Research》 2010年第11期1-3,共3页
Through the initial selection,screening and simplification,a set of performance appraisal system of logistic distribution suited to fresh agricultural products is established.In the process of establishing the apprais... Through the initial selection,screening and simplification,a set of performance appraisal system of logistic distribution suited to fresh agricultural products is established.In the process of establishing the appraisal indicator,the representative appraisal indicator of logistic distribution of fresh agricultural products is further obtained by delivering experts' survey and applying the ABC screening system.The distribution costs,transportation and service level belong to the first level indicator;packing fees,distribution processing fees,full-load ratio,haulage capacity,customer satisfaction and the strain capability of delivery personnel belong to second level indicator.At the same time,the weighing of each indicator is determined.The quantification is conducted on indicators.The qualitative indicators applies ten-point system and then coverts these indicators into percentage,that is the number between [0,1];as for the quantitative indicators,they are concluded to the interval [0,1] according to the actual value range of the indicators and by applying the grade of membership in the vague mathematics.Through the analyses of the advantages and disadvantages of the frequently used performance evaluation method and its applicable conditions,the comprehensive evaluation of logistic distribution of agricultural products obtained by using the method of fuzzy comprehensive appraisal.The results show that,in terms of reducing distribution costs,the packaging and distribution processing technology of fresh agricultural products should be improved,so as to reduce distribution costs.In the process of introducing the application of advanced technology,the high automatic logistic equipments should be introduced. 展开更多
关键词 LOGIsTIC distribution of FREsH AGRICULTURAL produc
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Research on the Mediating Effect of Market Benefit Between Dual Distribution Channel Conflicts and Financial Performance of Garment Enterprises
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作者 Yue Yanzai Qu Hongjian 《International English Education Research》 2014年第12期88-92,共5页
The paper discussed the impact of dual distribution channel conflicts on financial performance of garment enterprises by multiple regression and mediation effect has been analyzed with market benefit as the mediated v... The paper discussed the impact of dual distribution channel conflicts on financial performance of garment enterprises by multiple regression and mediation effect has been analyzed with market benefit as the mediated variable based on the survey data of Shanghai region. The results show that: first, channel contention, channel areal differences and channel perception differences have a negative effect on financial performance and channel communication has a positive effect on financial performance significantly; second, market benefit has a positive effect on financial performance significantly; third, channel contention, channel areal differences and channel perception differences have a negative effect on market benefit and channel communication has a positive effect on market benefit significantly; forth, market benefit has a partial mediation effect on the influence of channel areal differences and channel communication on financial performance. Therefore, channel areal differences and channel communication are two major aspects among the dual distribution channel conflicts which may have influences on financial benefit of garment enterprises, and clothing company should lay emphasis on the settling of these two matters. 展开更多
关键词 Dual distribution Channel Conflicts Financial performance Mediating Effect Empirical Analysis
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Classification, Gender and Age Differences, and Seasonal Changes in Relation to Patterns of Distribution Curves for Physique and Motor Performance in Preschool-Aged Japanese Children
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作者 Takahiro Ikeda Osamu Aoyagi 《Journal of Sports Science》 2017年第1期45-57,共13页
It is predicted that the distribution on score of children's motor performance show abnormal curve, because their physical fitness shows decline and gap between good and poor. The aim of present study is to type patt... It is predicted that the distribution on score of children's motor performance show abnormal curve, because their physical fitness shows decline and gap between good and poor. The aim of present study is to type pattern of distribution curve on physique and motor performance (PMP) in preschoolers, and to investigate gender difference, and change in season and age on distribution of PMP. Seven hundred and seven preschoolers participate in measurement on 21 items of PMP. And mix-longitudinal data which made from 6 terms (2 seasons of spring and autumn for 3 years) is completed. The histograms of 10 sections are trained for each gender, term, and test item based on range of data including mean ± 3 standard deviation. By cluster analysis and multi-correspondence analysis, "physique & jumping" show closely normal curve, but "manipulation (MP)" is skewed to poor and "running & prompt (RP)" is skewed to good. By Hotelling's T2-test and Mahalanobis' Distance, gender difference is shown that boys' RP is skewed to good, and their "throwing" and "weight & flexibility (WF)" are skewed to poor. About season, WF is skewed to poor and RP is skewed to good, in spring. In annual change about pattern of distribution, skewing poor in MP and good in "running straight & prompt" are changed to normal curve with aging. 展开更多
关键词 distribution gap of motor ability Hotelling's T2-test Mahalanobis Distance multi-correspondence analysis
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Molecular Weight Distribution of Dissolved Organic Matter in Lake Hongfeng Determined by High Performance Size Exclusion Chromatography (HPSEC) With On-Line UV-Vis Absorbance and Fluorescence Detection 被引量:3
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作者 岳兰秀 吴丰昌 +3 位作者 刘丛强 黎文 王静 梅毅 《Chinese Journal Of Geochemistry》 EI CAS 2004年第3期275-283,共9页
The molecular weight distribution (MWD) of dissolved organic matter (DOM) in lake waters from Lake Hongfeng was examined using high performance size exclusion chromatography (HPSEC) with UV-vis absorbance and fluoresc... The molecular weight distribution (MWD) of dissolved organic matter (DOM) in lake waters from Lake Hongfeng was examined using high performance size exclusion chromatography (HPSEC) with UV-vis absorbance and fluorescence detection. The elution curves obtained by absorbance and fluorescence techniques expressed similar patterns, with the exception of diminishing of large fraction and the peaks behind several seconds in fluorescence chromatograms. According to its molecular weight (MW), DOM in water samples is divided into several fractions: large ({>3.5} kDa); medium-large ({3.5}-{2.0} kDa); medium ({2.0}-{1.0} kDa) and small ({<1.0} kDa). The average molecular weight was calculated using the elution curve detected by UV-vis absorbance and fluorescence detection techniques. The results showed that the weight-average molecular weight (Mw) and number-average molecular weight (Mn) calculated by UV-vis absorbance techniques range from 1750 to 2050 Dalton and from 1450 to 1850 Dalton, respectively. And the Mw and Mn obtained by fluorescence detection are lower by 50 to 400 Dalton. As a reference, the molecular weight of Fluka humic acid (FHA) is larger than that of water samples by about 200 Dalton. The average molecular weight of DOM for water samples collected in March and July was compared. The results revealed that the molecular weight is lower for water samples obtained in July than that obtained in March, indicating the ambient environment has an influence on the molecular weight, including photo-degradation and biological activity. 展开更多
关键词 液化有机物 分子量 平均数 吸收比 荧光性 聚合化合物 湖水生物化学
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Neural stem cell-derived exosomes promote mitochondrial biogenesis and restore abnormal protein distribution in a mouse model of Alzheimer's disease 被引量:1
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作者 Bo Li Yujie Chen +10 位作者 Yan Zhou Xuanran Feng Guojun Gu Shuang Han Nianhao Cheng Yawen Sun Yiming Zhang Jiahui Cheng Qi Zhang Wei Zhang Jianhui Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1593-1601,共9页
Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheime... Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheimer’s disease affects the entire brain,further research is needed to elucidate alterations in mitochondrial metabolism in the brain as a whole.Here,we investigated the expression of several important mitochondrial biogenesis-related cytokines in multiple brain regions after treatment with neural stem cell-derived exosomes and used a combination of whole brain clearing,immunostaining,and lightsheet imaging to clarify their spatial distribution.Additionally,to clarify whether the sirtuin 1(SIRT1)-related pathway plays a regulatory role in neural stem cell-de rived exosomes interfering with mitochondrial functional changes,we generated a novel nervous system-SIRT1 conditional knoc kout AP P/PS1mouse model.Our findings demonstrate that neural stem cell-de rived exosomes significantly increase SIRT1 levels,enhance the production of mitochondrial biogenesis-related fa ctors,and inhibit astrocyte activation,but do not suppress amyloid-βproduction.Thus,neural stem cell-derived exosomes may be a useful therapeutic strategy for Alzheimer’s disease that activates the SIRT1-PGC1αsignaling pathway and increases NRF1 and COXIV synthesis to improve mitochondrial biogenesis.In addition,we showed that the spatial distribution of mitochondrial biogenesis-related factors is disrupted in Alzheimer’s disease,and that neural stem cell-derived exosome treatment can reverse this effect,indicating that neural stem cell-derived exosomes promote mitochondrial biogenesis. 展开更多
关键词 Alzheimer’s disease mitochondrial biogenesis neural stem cell-derived exosome sIRT1-PGC1α regional brain distribution whole brain clearing and imaging
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Spatiotemporal Distributions of Bacterioplankton Communities in the Qiantang River(Hangzhou Section),China
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作者 XU Jiaojiao ZHAO Li +4 位作者 LUKWAMBE Betina NICHOLAUS Regan ZHU Jinyong YANG Wen ZHENG Zhongming 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期1102-1114,共13页
The spatial and temporal distribution of bacterioplankton communities plays a vital role in understanding the ecological dynamics and health of aquatic ecosystems.In this study,we conducted a comprehensive investigati... The spatial and temporal distribution of bacterioplankton communities plays a vital role in understanding the ecological dynamics and health of aquatic ecosystems.In this study,we conducted a comprehensive investigation of the bacterioplankton communities in the Qiantang River(Hangzhou section).Water samples were collected quarterly from seven sites over a one-year period.Physical and chemical parameters,including dissolved oxygen(DO),water temperature(WT),chemical oxygen demand(COD),nitrite(NO_(2)^(-)),active phosphate(PO_(4)^(3-))and other indices were determined.In this study,theαdiversity,βdiversity and abundance differences of bacterial communities were investigated using 16S rRNA high-throughput sequencing analysis.The spatial and temporal distribution characteristics and main driving factors of the bacterioplankton community structure and diversity were discussed.The results showed that a total of 57 phyla were detected in the bacterioplankton community,among which Proteobacteria and Actinomycetes were the two dominant groups with the highest relative abundance.The results of PCoA based on Bray-Curtis distance showed that the sampling season had a slightly greater effect on the changes in bacterioplankton community structure in the Qiantang River.Mantel and partial Mantel test showed that environmental variables(Mantel r=0.6739,P<0.0001;partial Mantel r=0.507,P=0.0001)were more important than geographical distance(Mantel r=0.5322,P<0.001;partial Mantel r=0.1563,P=0.001).The distance attenuation model showed that there was significant distance attenuation in all four seasons,and the maximum limit of bacterial community diffusion was found in spring.RDA analysis showed that nine environmental factors,including COD,WT and DO,significantly affected community distribution(P<0.05).This study provides valuable insights into the spatial and temporal distribution characteristics of bacterioplankton communities,shedding light on their ecological roles in the Qiantang River.The information obtained can guide future research on the interactions between bacterioplankton and their environment,enabling the development of effective conservation strategies and sustainable management practices for aquatic ecosystems. 展开更多
关键词 Qiantang River bacterioplankton community spatial and temporal distribution 16s rRNA range attenuation
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Direct Yaw Moment Control for Distributed Drive Electric Vehicle Handling Performance Improvement 被引量:30
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作者 YU Zhuoping LENG Bo +2 位作者 XIONG Lu FENG Yuan SHI Fenmiao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第3期486-497,共12页
For a distributed drive electric vehicle(DDEV) driven by four in-wheel motors, advanced vehicle dynamic control methods can be realized easily because motors can be controlled independently, quickly and precisely. A... For a distributed drive electric vehicle(DDEV) driven by four in-wheel motors, advanced vehicle dynamic control methods can be realized easily because motors can be controlled independently, quickly and precisely. And direct yaw-moment control(DYC) has been widely studied and applied to vehicle stability control. Good vehicle handling performance: quick yaw rate transient response, small overshoot, high steady yaw rate gain, etc, is required by drivers under normal conditions, which is less concerned, however. Based on the hierarchical control methodology, a novel control system using direct yaw moment control for improving handling performance of a distributed drive electric vehicle especially under normal driving conditions has been proposed. The upper-loop control system consists of two parts: a state feedback controller, which aims to realize the ideal transient response of yaw rate, with a vehicle sideslip angle observer; and a steering wheel angle feedforward controller designed to achieve a desired yaw rate steady gain. Under the restriction of the effect of poles and zeros in the closed-loop transfer function on the system response and the capacity of in-wheel motors, the integrated time and absolute error(ITAE) function is utilized as the cost function in the optimal control to calculate the ideal eigen frequency and damper coefficient of the system and obtain optimal feedback matrix and feedforward matrix. Simulations and experiments with a DDEV under multiple maneuvers are carried out and show the effectiveness of the proposed method: yaw rate rising time is reduced, steady yaw rate gain is increased, vehicle steering characteristic is close to neutral steer and drivers burdens are also reduced. The control system improves vehicle handling performance under normal conditions in both transient and steady response. State feedback control instead of model following control is introduced in the control system so that the sense of control intervention to drivers is relieved. 展开更多
关键词 direct yaw moment control distributed drive electric vehicle handling performance improvement state feedback control
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Performance of Multirate Multicast in Distributed Network
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作者 Soumen Kanrar Mohammad Siraj 《International Journal of Communications, Network and System Sciences》 2010年第6期554-562,共9页
The number of Internet users has increased very rapidly due to the scalability of the network. The users demand for higher bandwidth and better throughput in the case of on demand video, or video conference or any rea... The number of Internet users has increased very rapidly due to the scalability of the network. The users demand for higher bandwidth and better throughput in the case of on demand video, or video conference or any real time distributed network system. Performance is a great issue in any distributed networks. In this paper we have shown the performance of the multicast groups or clusters in the distributed network system. In this paper we have shown the performance of different users or receivers belongs to the multicast group or cluster in the distributed network, transfer data from the source node with multirate multicast or unirate multicast by considering packet level forwarding procedure in different sessions. In this work we have shown that how the throughput was effected when the number of receiver increase. In this work we have considered the different types of queue such as RED, Fair queue at the junction node for maintaining the end to end packet transmission. In this work we have used various congestion control protocol at the sender nodes. This paper we have shown the performance of the distributed cluster network by multirate multicast. 展开更多
关键词 THROUGHPUT performance distributed Network Cluster MULTICAsT sEssION MULTIRATE MULTICAsT QUEUE
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Interaction of Units and Research Methods of Control Performances of Distributed Manufacturing Information System
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作者 张开升 孙延明 郑时雄 《Journal of Donghua University(English Edition)》 EI CAS 2008年第2期175-182,共8页
In order to analyze the function demand of the distributed manufacturing information system as well as its control demand, and eliminate information ambiguity among system units to integrate semantics, the abstract Ag... In order to analyze the function demand of the distributed manufacturing information system as well as its control demand, and eliminate information ambiguity among system units to integrate semantics, the abstract Agent model and computational structure of each unit was presented based on flexible coupling automata. The autonomy of each unit was investigated in this foundation. The system unit was described using the Web Ontology Language (OWL) ontology. And the system semantics was also integrated. On these basics the communication among the system units was analyzed with an example of interaction between a machine and a warehouse. The control performances of information system units were investigated using Boolean matrix as a substitute for traditional process in RW theory, which reduced the computational complexity. This work established the foundation for the demand analysis, design and development of the distributed manufacture information system. 展开更多
关键词 distributed manufacturing information system autonamy control performance ONTOLOGY semantic integration
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Performance Study of a Distributed Web Server: An Analytical Approach
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作者 Sarah Tasneem Reda Ammar 《Journal of Software Engineering and Applications》 2012年第11期855-863,共9页
With the rapid expansion of the Internet, Web servers have played a major role in accessing the enormous mass of Web pages to find the information needed by the user. Despite the exponential growth of the WWW, a very ... With the rapid expansion of the Internet, Web servers have played a major role in accessing the enormous mass of Web pages to find the information needed by the user. Despite the exponential growth of the WWW, a very negligible amount of research has been conducted in Web server performance analysis with a view to improve the time a Web server takes to connect, receive, and analyze a request sent by the client and then sending the answer back to client. In this paper, we propose a multi-layer analytical approach to study the web server performance. A simple client-server model is used to represent the WWW server in order to demonstrate how to apply the proposed approach. We developed a systematic, analytical methodology to quantify the communication delay and queuing overhead in a distributed web server system. The approach uses the Computation Structure Model to derive server processing time required to process a request sent from a client and queueing model to analyze the communication between the clients and the server. 展开更多
关键词 WEB sERVER CsM performance Modeling performance Analysis distributED systems QUEUEING Model
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A Performance-Driven Approach for Restructuring Distributed Object-Oriented Software
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作者 Amal Abd El-Raouf Tahany Fergany +1 位作者 Reda Ammar Safwat Hamad 《Journal of Software Engineering and Applications》 2009年第2期127-135,共9页
Object oriented techniques make applications substantially easier to build by providing a high-level platform for appli-cation development. There have been a large number of projects based on the Distributed Object Or... Object oriented techniques make applications substantially easier to build by providing a high-level platform for appli-cation development. There have been a large number of projects based on the Distributed Object Oriented approach for solving complex problems in various scientific fields. One important aspect of Distributed Object Oriented systems is the efficient distribution of software classes among different processors. The initial design of the Distributed Object Oriented application does not necessarily have the best class distribution and may require to be restructured. In this paper, we propose a methodology for efficiently restructuring the Distributed Object Oriented software systems to get better performance. We use Distributed Object-Oriented performance (DOOP) model as guidance for our restructuring methodology. The proposed methodology consists of two phases. The first phase introduces a recursive graph clustering technique to partition the OO system into subsystems with low coupling. The second phase is concerned with mapping the generated partitions to the set of available machines in the target distributed architecture. 展开更多
关键词 performance Modeling distributED OBJECT ORIENTED REsTRUCTURING METHODOLOGY
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Distributed multicast routing algorithm with dynamic performance in multimedia networks
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作者 Zhu Baoping Zhang Kun 《Engineering Sciences》 EI 2009年第3期28-34,共7页
The delay and DVBMT problem is known to be NP-complete. In this paper,an efficient distributed dynamic multicast routing algorithm was proposed to produce routing trees with delay and delay variation constraints. The ... The delay and DVBMT problem is known to be NP-complete. In this paper,an efficient distributed dynamic multicast routing algorithm was proposed to produce routing trees with delay and delay variation constraints. The proposed algorithm is fully distributed,and supports the dynamic reorganizing of the multicast tree in response to changes for the destination. Simulations demonstrate that our algorithm is better in terms of tree delay and routing success ratio as compared with other existing algorithms,and performs excellently in delay variation performance under lower time complexity,which ensures it to support the requirements of real-time multimedia communications more effectively. 展开更多
关键词 multicast routing distributed algorithm dynamic performance delay and delay variation-bounded multimedia networks
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Dynamic-Distributed Load Balancing for Highly-Performance and Responsiveness Distributed-GIS (D-GIS)
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作者 Aissatou Diasse Foroski Kone 《Journal of Geographic Information System》 2011年第2期128-139,共12页
In recent years, several results have been introduced to enhance distributed GIS performance. While much more efforts have focused on tile map and simple symbologies on dynamic map, load balancing GIS servers have not... In recent years, several results have been introduced to enhance distributed GIS performance. While much more efforts have focused on tile map and simple symbologies on dynamic map, load balancing GIS servers have not been addressed by the GIS community so far. This paper, therefore, proposed dynamic distributed load balancing for D-GIS in order to quickly render information to client interface by involving a set of GIS servers which process clients’ requests depending of an algorithm. In the model, several concepts were introduced and defined: Virtual Server within physical machine which constitutes a setup environment for a single GIS server, Load Hash Table which contains information about virtual server’s capacity, real-time load and other mandatory elements, Request Split Table which splits requests depending of the input area’s Quantity of Information and stores request tasks composition for later reconstitution. At last we have Distributed Failover Callback Function Table level one (respectively level two) which determines whether or not the request had been successfully processed by the chosen virtual server (respectively physical machine). This table allows sending back the same request to another virtual server (respectively physical node). Two load handlers (primary and secondary) are defined in case of failure. Our Model achieves efficient load balancing by: providing efficient node selection;optimizing request routing;managing node failover;involving client’s request partitioning and introducing method type decomposition. A simulation of the algorithm shows a low response time when performing GIS operations. 展开更多
关键词 LOAD Balancing distributed-GIs performance REsPONsIVENEss
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A Model of the Fatigue Life Distribution of Composite Laminates Based on Their Static Strength Distribution 被引量:7
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作者 吴富强 姚卫星 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第3期241-246,共6页
The reasons of the static strength dispersion and the fatigue life dispersion of composite laminates are analyzed in this article. It is concluded that the inner original defects, which derived from the manufacturing ... The reasons of the static strength dispersion and the fatigue life dispersion of composite laminates are analyzed in this article. It is concluded that the inner original defects, which derived from the manufacturing process of composite laminates, are the common and major reason of causing the random distributions of the static strength and the fatigue life. And there is a correlative relation between the two distributions. With the study of statistical relationship between the fatigue loading and the fatigue life in the uniform confidence level and the same survival rate S-N curves of material, the relationship between the static strength distribution and the fatigue life distribution through a material S-N curve model has been obtained. And then the model which is used to describe the distributions of fatigue life of composites, based on their distributions of static strength, is set up. This model reasonably reflects the effects of the inner original defects on the static strength dispersion and on the fatigue life dispersion of composite laminates. The experimental data of three kinds of composite laminates are employed to verify this model, and the results show that this model can predict the random distributions of fatigue life for composites under any fatigue loads fairly well. 展开更多
关键词 COMPOsITE static strength fatigue life s-N curve random distribution
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