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基于Web服务的跨企业“三动态”工作流管理解决方案
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作者 叶远军 阎春平 刘飞 《现代制造工程》 CSCD 2006年第6期14-17,共4页
采用动态定义企业业务流程、动静态调用流程服务中各W eb服务节点和动态发布企业服务的“三动态”管理策略,设计一种基于W eb服务的新型“三动态”工作流服务模型,提出一种基于W eb服务的跨企业“三动态”工作流解决方案,深入研究了实... 采用动态定义企业业务流程、动静态调用流程服务中各W eb服务节点和动态发布企业服务的“三动态”管理策略,设计一种基于W eb服务的新型“三动态”工作流服务模型,提出一种基于W eb服务的跨企业“三动态”工作流解决方案,深入研究了实现动态调用的动态服务代理机制,进一步阐述其他系统管理策略。 展开更多
关键词 “三动态” 动态定义 动静态调用 动态发布
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邹庄煤矿7401工作面采空区动态自燃“三带”变化规律研究
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作者 孟刚 武向强 《采矿技术》 2024年第2期165-172,共8页
通常一个工作面只测定一次采空区自燃“三带”。但工作面遇到断层、煤厚变化时,会阻碍推进速度,同时也影响采空区的氧化进程,因此,采空区自燃“三带”是动态变化的。为了研究采空区动态自燃“三带”变化规律,通过在现场铺设束管系统测... 通常一个工作面只测定一次采空区自燃“三带”。但工作面遇到断层、煤厚变化时,会阻碍推进速度,同时也影响采空区的氧化进程,因此,采空区自燃“三带”是动态变化的。为了研究采空区动态自燃“三带”变化规律,通过在现场铺设束管系统测量采空区氧气随温度的变化规律。基于氧气浓度的变化,提出了一种基于煤温变化的升温幅度法,并利用分布式光纤测温系统监测实时温度进行“三带”划分。结果表明:研究断层复杂地区使得自然“三带”扩大;煤层越厚,氧化带越窄;推进速度加快时,整体氧化带发生后移现象。 展开更多
关键词 邹庄煤矿 升温幅度法 分布式光纤测温系统 动态自燃“三带”
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剩余价值生产的“三阶段”动态模式构建及“四要素”分析 被引量:1
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作者 刘冠军 《当代经济研究》 CSSCI 北大核心 2015年第9期12-20,97,共9页
在"科技-经济"一体化新时代背景下,现代科技企业的"总体工人"是由"在场的"生产工人、"准在场的"技术人员和"不在场的"科学人员构成的,其"整体劳动系统"表现出"跨时空... 在"科技-经济"一体化新时代背景下,现代科技企业的"总体工人"是由"在场的"生产工人、"准在场的"技术人员和"不在场的"科学人员构成的,其"整体劳动系统"表现出"跨时空"的特征,因此,其剩余价值生产依次展现为"不在场的"科学人员、"准在场的"技术人员、"在场的"生产工人的劳动过程和价值增殖过程,这构成了现代科技企业剩余价值生产的"三阶段"动态模式。要对这一模式进行深入系统的理论分析,必须将马克思商品价值构成的"三要素"理论拓展为科技商品价值构成的"四要素"学说。运用"四要素"学说对其分析发现,现代科技企业剩余价值的生产在三个阶段上既包括显性或直观层面上"显在价值"的创造和转移,也包括隐性或实质层面上"潜在价值"的创造和转移;现代科技企业获得的剩余价值,既包括"在场的"生产工人和"准在场的"技术人员所创造的剩余价值,也包括"不在场的"科学人员所创造的剩余价值。 展开更多
关键词 剩余价值生产 “三阶段”动态模式 “四要素”分析 “科技-经济”一体化 现代科技劳动价值论
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“三阶段”动态教学法在《Java程序设计》课程的探索与实践
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作者 冯晶莹 《辽宁警专学报》 2014年第5期98-100,共3页
Java是一门面向对象的编程语言,需要在课程中逐渐提高学生的动手实践能力,根据此课程的特点,在课程中引入"三阶段"动态教学法,革新课程考核方式,通过之后的问卷调查和考试效果显示达到了较好的教学效果。
关键词 JAVA “三阶段”动态教学法 实践教学
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千米深井大断面穿煤巷道“三锚”动态联合支护技术及应用 被引量:1
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作者 邹钰 《山东煤炭科技》 2016年第2期51-52,共2页
随着矿井开采深度的增加,矿山压力不断增大,尤其是千米深井大断面、穿煤巷道施工,传统的架棚支护工艺复杂、费用高、巷道维修量大,给安全生产带来困难。信湖煤矿根据实际情况,采用"三锚(锚杆、锚索、锚注)"动态联合支护技术,... 随着矿井开采深度的增加,矿山压力不断增大,尤其是千米深井大断面、穿煤巷道施工,传统的架棚支护工艺复杂、费用高、巷道维修量大,给安全生产带来困难。信湖煤矿根据实际情况,采用"三锚(锚杆、锚索、锚注)"动态联合支护技术,在-952回风石门揭穿3煤段进行实践,取得了良好的支护效果,为类似巷道的支护提供有益的参考和借鉴。 展开更多
关键词 千米深井 大断面 穿煤巷道 “三锚”动态联合支护
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煤炭企业推行“三工”动态竞争考核的实践与探索
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作者 沈欣 《能源技术与管理》 2006年第4期109-110,共2页
针对目前煤炭企业员工管理的现状,阐述了煤炭企业员工推行“三工”动态考核内涵、考核目标、考核办法及保证措施。
关键词 “三工”动态考核 内涵 目标 办法 措施
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基于TOPSIS和灰色关联投影法的区域碳效率动态综合评价——以泛珠三角为例
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作者 何燕子 王妍 《湖南工业大学学报》 2023年第6期61-68,共8页
为弥补传统碳效率评价偏向绝对量指标或者少数几个指标的单点式评价的不足,选取相对量指标,从经济、人口、福利多个维度并兼顾地区发展实际与公平原则,构建区域碳效率评价指标体系。将TOPSIS法与灰色关联投影分析相结合,并利用时间序列... 为弥补传统碳效率评价偏向绝对量指标或者少数几个指标的单点式评价的不足,选取相对量指标,从经济、人口、福利多个维度并兼顾地区发展实际与公平原则,构建区域碳效率评价指标体系。将TOPSIS法与灰色关联投影分析相结合,并利用时间序列平均算子二次加权以实现对泛珠三角9省(自治区)2011—2020年碳效率的动态综合评价。静态与动态评价研究结果显示:该区域碳效率发展水平存在差异,其中海南省碳效率总体水平较高,为0.530;贵州省碳效率相对较低,为0.162;海南省比贵州省高出227%。福建省碳效率呈上升趋势,由2011年的0.327上升至2020年的0.498,增长了52.3%。研究认为,应该制定差异化减排策略、加大技术经费投入、增强社会福利、引进人才以实现低碳经济发展。 展开更多
关键词 泛珠 碳效率 TOPSIS 灰色关联投影法
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Numerical Investigations on Dynamic Stall Characteristics of a Finite Wing
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作者 JING Simeng CAO Chenkai +2 位作者 GAO Yuan ZHAO Qijun ZHAO Guoqing 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第4期444-457,共14页
The paper examines the dynamic stall characteristics of a finite wing with an aspect ratio of eight in order to explore the 3D effects on flow topology,aerodynamic characteristics,and pitching damping.Firstly,CFD meth... The paper examines the dynamic stall characteristics of a finite wing with an aspect ratio of eight in order to explore the 3D effects on flow topology,aerodynamic characteristics,and pitching damping.Firstly,CFD methods are developed to calculate the aerodynamic characteristics of wings.The URANS equations are solved using a finite volume method,and the two-equation k-ωshear stress transport(SST)turbulence model is employed to account for viscosity effects.Secondly,the CFD methods are used to simulate the aerodynamic characteristics of both a static,rectangular wing and a pitching,tapered wing to verify their effectiveness and accuracy.The numerical results show good agreement with experimental data.Subsequently,the static and dynamic characteristics of the finite wing are computed and discussed.The results reveal significant 3D flow structures during both static and dynamic stalls,including wing tip vortices,arch vortices,Ω-type vortices,and ring vortices.These phenomena lead to differences in the aerodynamic characteristics of the finite wing compared with a 2D airfoil.Specifically,the finite wing has a smaller lift slope during attached-flow stages,higher stall angles,and more gradual stall behavior.Flow separation initially occurs in the middle spanwise section and gradually spreads to both ends.Regarding aerodynamic damping,the inboard sections mainly generate unstable loading.Furthermore,sections experiencing light stall have a higher tendency to produce negative damping compared with sections experiencing deep dynamic stall. 展开更多
关键词 finite wing dynamic stall aerodynamic damping 3D effects
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ANALYSIS AND MEASUREMENT FOR THE DYNAMIC ERRORS OF COORDINATE MEASURING MACHINES 被引量:2
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作者 董晨松 张国雄 《Transactions of Tianjin University》 EI CAS 1998年第2期63-67,共5页
The analysis and calculating method of dynamic errors of CMMs during probing are discussed.To relate the dynamic displacement errors with the dynamic rotational errors a method for obtaining the displacement errors at... The analysis and calculating method of dynamic errors of CMMs during probing are discussed.To relate the dynamic displacement errors with the dynamic rotational errors a method for obtaining the displacement errors at the probing position from dynamic rotational errors is presented.It is pointed out that the finite element method might be used for modeling dynamic errors.However,dynamic errors are difficult to be modeled so a combined practical and theoretical approach is needed.In addition,the dynamic errors are measured with inductive position sensors. 展开更多
关键词 coordinate measuring machine (CMM) dynamic error finite element method(FEM)
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Dynamic load balancing based on restricted multicast tree in triplet-based hierarchical interconnection network
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作者 刘滨 石峰 +2 位作者 高玉金 计卫星 宋红 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期33-37,共5页
To solve the load balancing problem in a triplet-based hierarchical interconnection network(THIN) system, a dynamic load balancing (DLB)algorithm--THINDLBA, which adopts multicast tree (MT)technology to improve ... To solve the load balancing problem in a triplet-based hierarchical interconnection network(THIN) system, a dynamic load balancing (DLB)algorithm--THINDLBA, which adopts multicast tree (MT)technology to improve the efficiency of interchanging load information, is presented. To support the algorithm, a complete set of DLB messages and a schema of maintaining DLB information in each processing node are designed. The load migration request messages from the heavily loaded node (HLN)are spread along an MT whose root is the HLN. And the lightly loaded nodes(LLNs) covered by the MT are the candidate destinations of load migration; the load information interchanged between the LLNs and the HLN can be transmitted along the MT. So the HLN can migrate excess loads out as many as possible during a one time execution of the THINDLBA, and its load state can be improved as quickly as possible. To avoid wrongly transmitted or redundant DLB messages due to MT overlapping, the MT construction is restricted in the design of the THINDLBA. Through experiments, the effectiveness of four DLB algorithms are compared, and the results show that the THINDLBA can effectively decrease the time costs of THIN systems in dealing with large scale computeintensive tasks more than others. 展开更多
关键词 triplet-based hierarchical interconnection network dynamic load balancing multicast tree
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Continuous TDEM for monitoring shale hydraulic fracturing 被引量:15
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作者 Yan Liang-Jun Chen Xiao-Xiong +4 位作者 Tang Hao Xie Xing-Bing Zhou Lei Hu Wen-Bao and Wang Zhong-Xin 《Applied Geophysics》 SCIE CSCD 2018年第1期26-34,147,148,共11页
Monitoring and delineating the spatial distribution of shale fracturing is fundamentally important to shale gas production. Standard monitoring methods, such as time-lapse seismic, cross-well seismic and micro-seismic... Monitoring and delineating the spatial distribution of shale fracturing is fundamentally important to shale gas production. Standard monitoring methods, such as time-lapse seismic, cross-well seismic and micro-seismic methods, are expensive, time- consuming, and do not show the changes in the formation with time. The resistivities of hydraulic fracturing fluid and reservoir rocks were measured. The results suggest that the injection fluid and consequently the injected reservoir are characterized by very low resistivity and high chargeability. This allows using of the controlled-source electromagnetic method (CSEM) to monitor shale gas hydraulic fracturing. Based on the geoelectrical model which was proposed according to the well-log and seismic data in the test area the change rule of the reacted electrical field was studied to account for the change of shale resistivity, and then the normalized residual resistivity method for time lapse processing was given. The time-domain electromagnetic method (TDEM) was used to continuously monitor the shale gas fracturing at the Fulin shale gas field in southern China. A high-power transmitter and multi-channel transient electromagnetic receiver array were adopted. 9 h time series of Ex component of 224 sites which were laid out on the surface and over three fracturing stages of a horizontal well at 2800 m depth was recorded. After data processing and calculation of the normalized resistivity residuals, the changes in the Ex signal were determined and a dynamic 3D image of the change in resistivity was constructed. This allows modeling the spatial distribution of the fracturing fluid. The model results suggest that TDEM is promising for monitoring hydraulic fracturing of shale. 展开更多
关键词 Shale fracturing RESISTIVITY time lapse 3D imaging continuous monitoring
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Research on identifying the dynamic error model of strapdown gyro on 3-axis turntable 被引量:5
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作者 王海 任顺清 王常虹 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第6期630-634,共5页
The dynamic errors of gyros are the important error sources of a strapdown inertial navigation system. In order to identify the dynamic error model coefficients accurately, the static error model coefficients which la... The dynamic errors of gyros are the important error sources of a strapdown inertial navigation system. In order to identify the dynamic error model coefficients accurately, the static error model coefficients which lay a foundation for compensating while identifying the dynamic error model are identified in the gravity acceleration fields by using angular position function of the three-axis turntable. The angular acceleration and angular velocity are excited on the input, output and spin axis of the gyros when the outer axis and the middle axis of a three-axis turntable are in the uniform angular velocity state simultaneously, while the inner axis of the turntable is in different static angular positions. 8 groups of data are sampled when the inner axis is in 8 different angular positions. These data are the function of the middle axis positions and the inner axis positions. For these data, harmonic analysis method is applied two times versus the middle axis positions and inner axis positions respectively so that the dynamic error model coefficients are finally identified through the least square method. In the meantime the optimal angular velocity of the outer axis and the middle axis are selected by computing the determination value of the information matrix. 展开更多
关键词 strapdown gyro dynamic error model harmonic analysis three-axis turntable
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Seasonal Dynamics of Nitrogen and Phosphorus in Water and Sediment of A Multi-level Ditch System in Sanjiang Plain,Northeast China 被引量:6
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作者 GUO Le MA Keming 《Chinese Geographical Science》 SCIE CSCD 2011年第4期437-445,共9页
The multi-level ditch system developed in the Sanjiang Plain,Northeast China has sped up water drainage process hence transferred more pollutants from farmlands into the rivers of this region.Understanding the seasona... The multi-level ditch system developed in the Sanjiang Plain,Northeast China has sped up water drainage process hence transferred more pollutants from farmlands into the rivers of this region.Understanding the seasonal dynamics of nitrogen (N) and phosphorus (P) transportation in the ditch system and the role of different ditch size is thus crucial for water pollution control of the rivers in the Sanjiang Plain.In this study,an investigation was conducted in the Nongjiang watershed of the Sanjiang Plain to study the nutrient variation and the correlation between water and sediments in the ditch system in terms of ditch level.Water and sediments samples were collected in each ditch level in growing season at regular intervals (once per month),and TN,NO 3--N,NH 4+-N,TP,and PO 4 3--P were analyzed.The results show that nutrient contents in water were higher in June and July,especially in July,the contents of TN and TP were 3.21mg/L and 0.84mg/L in field ditch,4.04mg/L and 1.06mg/L in lateral ditch,2.46mg/L and 0.70mg/L in branch ditch,1.92mg/L and 0.63mg/L in main ditch,respectively.In August and September,the nutrient contents in the water were relatively lower.The peak value of nutrient in ditch water had been moving from the field ditch to the main ditch over time,showing a remarkable impact of ditch system on river water environment.The nutrient transfer in ditch sediments could only be found in rainfall season.Nutrient contents in ditch sediment had effect on that in ditch water,but nutrients in ditch water and sediments had different origination.Ditch management in terms of the key fac-tors is hence very important for protecting river water environment. 展开更多
关键词 multi-level ditch system nitrogen PHOSPHORUS spatio-temporal variation drainage water sediment
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成果导向(OBE)视阈下的“三段式验证”动态教学评价模式探索和实践 被引量:6
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作者 胡盛骑 霍星 《创新创业理论研究与实践》 2019年第8期74-75,共2页
依据OBE教育理念,运用'三段式验证'动态教学评价模式,在艺术设计类各专业课程建设中的研究和实践,取得的成果及存在问题。
关键词 成果导向OBE教育理念的实践 艺术设计类专业 “三段式验证”动态教学评价模式
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Science Letters:Dynamic concision for three-dimensional reconstruction of human organ built with virtual reality modelling language (VRML) 被引量:3
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作者 禹正杨 郑树森 +2 位作者 陈雷霆 何晓乾 王建军 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第7期611-616,共6页
This research studies the process of 3D reconstruction and dynamic concision based on 2D medical digital images using virtual reality modelling language (VRML) and JavaScript language, with a focus on how to realize t... This research studies the process of 3D reconstruction and dynamic concision based on 2D medical digital images using virtual reality modelling language (VRML) and JavaScript language, with a focus on how to realize the dynamic concision of 3D medical model with script node and sensor node in VRML. The 3D reconstruction and concision of body internal organs can be built with such high quality that they are better than those obtained from the traditional methods. With the function of dynamic concision, the VRML browser can offer better windows for man-computer interaction in real-time environment than ever before. 3D reconstruction and dynamic concision with VRML can be used to meet the requirement for the medical observation of 3D reconstruction and have a promising prospect in the fields of medical imaging. 展开更多
关键词 Virtual Reality Modelling Language (VRML) Direct texture mapping Three-dimensional reconstruction Dynamic concision
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Study on Characteristic of Electric Power Assist Steering System 被引量:1
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作者 许镇琳 王豪 +2 位作者 尚喆 张海华 王家军 《Transactions of Tianjin University》 EI CAS 2003年第3期211-213,共3页
A pinion-type electric power steering (EPS) equipped on a sedan is reached in this paper. A three-freedom dynamic model of this system is created. The variables affecting assist character is analyzed. The formulas of ... A pinion-type electric power steering (EPS) equipped on a sedan is reached in this paper. A three-freedom dynamic model of this system is created. The variables affecting assist character is analyzed. The formulas of simpled steering resistance force and the relationship between assist gain and vehicle speed are presented for the first time. Assist character is found based on the parameters of a sedan at last. This assist character is fit for the control rule of the EPS system through analyzing this character. The assist character figure offers reference for system design and control. Furthermore, this research method has generality for assist character of different kinds of vehicles. 展开更多
关键词 VEHICLE electric power steering assist steering assist characteristic
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Dynamic characteristics of the high-flow water three-way valve 被引量:2
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作者 Chuan-Li WANG Xia GAO Hai-Shun DENG Yu HUANG 《Journal of Coal Science & Engineering(China)》 2013年第3期392-395,共4页
Operating principle of water three-way valve with high flow for individual hydraulic prop in coal was presented in this paper, its strict and precise mathematical model was established, its flow field was simulated nu... Operating principle of water three-way valve with high flow for individual hydraulic prop in coal was presented in this paper, its strict and precise mathematical model was established, its flow field was simulated numerically by software Fluent, and its dynamic characteristics were analyzed during the work process such as raising leg, loading and overflow, the influence of the related parameters on high-flow water three-way valve was determined. The results as follows: during the raising leg stage and early raising leg stage, when the damping ratio increases, the overshoot of system decreases and the setting time reduces, and the dynamic response performance has a significant improvement. During the loading stage and the overflow stage, the pressure in plunger chamber of single hydraulic prop, the output flow and the displacement of the high-flow water three-way valve decrease with the decreasing of the external load. The spring stiffness of the safety valve directs the flow and the spool's displacement of the safety valve, and it can be used to control the high-flow three-way valve's sensitivity. 展开更多
关键词 high-flow three-way valve water hydraulic structural design dynamic characteristics
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Statistical analysis of pressure fluctuations during unsteady flow for low-specific-speed centrifugal pumps 被引量:3
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作者 裴吉 王文杰 袁寿其 《Journal of Central South University》 SCIE EI CAS 2014年第3期1017-1024,共8页
A three-dimensional transient numerical simulation was conducted to study the pressure fluctuations in low-specific-speed centrifugal pumps. The characteristics of the inner flow were investigated using the SST k-ω t... A three-dimensional transient numerical simulation was conducted to study the pressure fluctuations in low-specific-speed centrifugal pumps. The characteristics of the inner flow were investigated using the SST k-ω turbulence model. The distributions of pressure fluctuations in the impeller and the volute were recorded, and the pressure fluctuation intensity was analyzed comprehensively, at the design condition, using statistical methods. The results show that the pressure fluctuation intensity increases along the impeller streamline from the leading edge to the trailing edge. In the impeller passage, the intensity near the shroud is much higher than that near the hub at thc inlet. However, the intensity at the middle passage is almost equal to the intensity at the outlet. The pressure fluctuation intensity is the highest at the trailing edge on the pressure side and near the tongue because of the rotor-stator interaction. The distribution of pressure fluctuation intensity is symmetrical in the axial cross sections of the volute channel. However, this intensity decreases with increasing radial distance. Hence, the pressure fluctuation intensity can be reduced by modifying the geometry of the leading edge in the impeller and the tongue in the volute. 展开更多
关键词 TRANSIENT pressure fluctuation intensity STATISTICS low specific speed centrifugal pump
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Reconstruction of three-dimensional coronary arterial dynamics from multi-viewangiogram sequences
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作者 SUN Zheng YU Dao-yin 《Optoelectronics Letters》 EI 2006年第1期68-71,共4页
A method for reconstructing 3-D motion of coronary arteries from single-plane X-ray angiogram sequences on two approximately orthogonal views is proposed. 2-D motion is firstly estimated separately along vascular cent... A method for reconstructing 3-D motion of coronary arteries from single-plane X-ray angiogram sequences on two approximately orthogonal views is proposed. 2-D motion is firstly estimated separately along vascular centerlines extracted from angiographic projection pairs. The 3-D displacement vector of each arterial skeleton point at one instant is then reconstructed by calculating the spatial coordinates of its two ends from corresponding projections. 3-D configuration and dynamics of arteries are finally characterized. The effectiveness of the algorithm has been demonstrated on vascular phantom images and clinical angiograms and results are encouraqing. 展开更多
关键词 冠状动脉 动态 血管造影 多视图序列
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SARC Model for Three-Dimensional Coordinate Transformation
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作者 YAO Jili WANG Shuguang SUN Yating 《Geo-Spatial Information Science》 2006年第2期84-88,共5页
In this paper, a transformation model named SARC(static-filter adjustment with restricted condition) is presented, which is more practical and more rigorous in theory and fitting any angle of rotation parameter. The t... In this paper, a transformation model named SARC(static-filter adjustment with restricted condition) is presented, which is more practical and more rigorous in theory and fitting any angle of rotation parameter. The transformation procedure is divided into 4 steps: ① the original and object coordinates can be regarded as observations with errors; ② rigorous formula is firstly deduced in order to compute the first approximation of the transformation parameters by use of four common points and the transformation equation is linearized; ③ calculate the most probable values and variances of the seven transformation parameters by SARC model; ④ to demonstrate validity of SARC , an example is given. 展开更多
关键词 SARC 3D coordinate transformation transformation parameters transformation equation
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