模拟
- 与 模拟 相关的网络例句 [注:此内容来源于网络,仅供参考]
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The main work and the originality points of this dissertation could be concluded as the following parts:(1) To analyze systematically the mathematical model of LES of air flow in great space, under the case of isothermal and non-isothermal, as well as the combined action of buoyancy and strain. Some basic problems are studied about the LES application into airflow simulation of great space, such as boundary conditions, spatial difference scheme and time advancing scheme, time step etc., which creates the basis for the LES application to indoor airflow simulation.(2) Both the instantaneous and time averaged flow field of great space with multiple jets under isothermal and non-isothermal cases are explored with large eddy simulation method, and also discussed the dynamic characteristics and the law of fluidflow in the great space.(3) Based on the results of LES of the great space and the Fanger thermal comfort indexes, it is brought forward the concept of the series of dynamic thermal comfort evaluating indexes, which could be divided into thermal comfort index with time averaged properties PD, PPD, PMV, thermal comfort index with instantaneous properties IPD, IPPD, IPMV, and time averaged thermal comfort indexes TAPD, TAPPD, TAPMV, and transient situations time averaged thermal comfort indexes TTAPD, TTAPPD, TTAPMV. The differences among them and the calculation methods are discussed, and the four kinds of indexes are calculated with the thermal comfort index PD as an example.(4) Based on the LES results it is discussed the hot air stratification phenomena in air-conditioned buildings in the case with air supply and return registers on the ceiling and the case on the sidewall. The fundamentals of the hot air stratification are studied and the relations of estimating hot air stratification are brought forward.(5) With the advanced apparatus such as hot wire film anemometer IFA300 and laser particle field anemoscope, corresponding model test and site measurements have been done, which are compared with the simulation results and LES is proved a very promising method in air flow simulation indoor.
本文主要工作既创新点体现在以下几个方面:(1)系统分析了等温、非等温和考虑剪切力与浮升力综合作用的高大空间大涡模拟数学模型,并研究了高大空间大涡模拟在室内气流仿真应用中的一些基本问题,如边界条件、空间离散格式和时间推进格式、时间步长选择等问题,为大涡模拟在室内气流计算中的广泛应用打下了基础;(2)首次用大涡模拟方法研究了高雷诺数下高大空间多射流在等温、非等温情况下的瞬时流场和时均流场分布,并探讨了多射流流场的动态特性和流动规律;(3)基于大涡模拟的动态仿真结果和Fanger的热舒适指标,首次系统地提出了动态热舒适评价指标体系的概念:即基于时间平均参数的热舒适指标PD、PPD、PMV;基于瞬时参数的瞬时热指标IPD、IPPD、IPMV;基于时间平均热舒适指标TAPD、TAPPD、TAPMV;以及沿行动迹线的时间平均热舒适指标TTAPD、TTAPPD、TTAPMV,并分析了四类热舒适指标的差异性和计算方法,还以PD值为例对四类指标分别进行了计算;(4)基于数十种工况下空调房间大涡模拟的结果,研究了空调建筑上送上回和侧送侧回两种情况下热分层现象,并探讨了热分层的基本规律,首次提出了避免热分层现象的判断公式;(5)在暖通空调领域,首次使用IFA300热线风速仪、激光粒子速度场仪等先进设备,完成了与大涡模拟相对应的模型试验,并把实测结果与仿真结果进行了对比,说明LES在室内气流仿真方面是一种很有前景的方法。
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A theoretical model is built to investigate the simulation of the infrared characteristic of the metal structure with the PCM false target.Structure parameters of the PCM false target that suit for the simulation are investigated numerically.According to the results,further request on the improvement of the thermal conductivity of PCM is presented.An experimental platform is built and the numerical model is validated experimentally.Three key thermal characteristic components of the false tank(barbette,wheel and front armor plate) are manufactured and tested,and good results are obtained.A method for the thermal conductivity enhancing of PCM by using aluminum fins is studied,the influence of the structure parameters of PCM plates to the simulation effects are investigated numerically,and the reasonable configuration parameters of the PCM plates used to simulate the steel plates of different thickness are obtained.In the study of the application of heat convection method in IR false target,a passive infrared simulation system is designed to simulate the infrared characteristic of metal constructions.The system is made up of pipe-plate,pump,receiver,and working fluid.
在相变材料应用于红外示假的研究中,通过数值模拟,研究确定了适用于制作假目标的相变材料各物性参数的范围,分析了相变材料制作假目标的可行性,并根据所得结果,选取石蜡为研究对象,建立了相变材料模拟金属构件红外特征的理论模型,研究了适用于模拟各金属构件红外特征的相变材料假目标的相关结构参数,得出了相变材料假目标模拟各金属构件红外特征的理论结果,并对相变材料的导热系数这一物性提出了进一步的改进要求;搭建了假目标实验平台,验证了所建理论模型的准确性;以坦克假目标为研究对象,制作了炮塔、负重轮和前上装甲板三个坦克假目标的关键红外热特征部件,并进行了野外实验,取得了较好的结果;以添加铝肋片作为改进相变材料导热能力的手段,理论研究了此类导热增强型相变材料的相关结构参数对模拟效果的影响,得出了模拟不同厚度钢板红外特征的导热增强型相变材料的结构参数及模拟效果。
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In order to realize the compatible communications system between digital TETRA and analogy MPT1327. Communications protocol between digital radio and control center is defined. Emergency call software flow for TETRA and MPT module is designed, and also state information sending and receiving for TETRA and MPT module is designed in this communication system. By comparing several solutions, switch methods between analogy TETRA communications and digital TETRA communications are designed including manual-switch and soft-switch. In the article, coding module of receiving and sending equipments in TATT analogy TETRA communications is described, so that it can be compatible with NOKIA network equipments and it also can improve the availability rate of the trunk system. In order to realize the integration of digital TETRA communication and analogy MPT1327 communications, double- frequency antenna system is researched.
通过几种车载电台解决方案比较,设计了相应的模拟集群通信系统与数字集群通信系统的切换方法,其中包括人工切换和软切换,实现了模拟与数字集群兼容的一体化移动列车调度电台解决方案;为了实现数字集群通信系统与模拟集群通信系统以及NOKIA与TAIT模拟集群通信系统之间的相互兼容,设计了新的数字车载电台与控制中心之间的通信协议;系统设计了用于数字集群通信模块的紧急呼叫通讯流程,以及设计了用于模拟集群通信模块状态信息发送与接收流程,以满足列车无线调度的运营要求;论文还论述了对TAIT模拟集群收发设备编码模块的改造,使之能与NOKIA的集群设备相兼容,提高了集群设备的利用率,为在NOKIA模拟集群通讯模块停产后寻找了一种可替代的兼容解决方案;为了实现数字集群通信系统与模拟集群通信系统设备的综合,论文还探讨了本工作所需专用的双频段的天线系统。
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The geology research of carbonate reservoirs in Ordovician of Tahe oilfield showed that many large dissolved vugs and fractures were developed. The spread of the reservoir take on a very heterogeneous state. And the typical fractured-vuggy reservoirs was formed. According to the combination of the various spaces, the formation was divided into vuggy formation, fractured-vuggy formation and fractured formation. The research showed that development of the vug is relevant to the its position on the structure, the fractures, the water surface and the weathering surface. Multi-phase charge and recharge of the oil in the reservoirs resulted in the complexity of the fluid distribution. So the"Bottle Model"was brought forward to explain the movement of the water-oil contact. The special storage space and the complex fluid distribution lead to the unstability of the production and the complexity of the water cut. In order to explain the characteristic of the fracture-vug unit was brought forward and the basic principle and method of the partition of the fracture-vug unit was formed. The classification and evaluation of the units were performed according the reserve and energy. Based on the research of geology characteristic and the fluid flow in the reservoir the comprehensive numerical simulation plan of the fractured-vuggy reservoirs were established. Through the selection of the simulation unit, fluid flow type and parameter equivalent the triple media reservoir simulation model was established. Considering the practical application the model was resolved by the DKR decomposition conjugate grads method. Based on the fine reservoir description of Dsitrict IV of the Tahe oilfield the various space type were classified and combined together. The geology model of Unit S48 was constructed. Two typical single well model was established according to the geology and the dynamic phenomena. Finally the single well model and the Unit S48 were simulated by the triple media reservoir simulator. Via the local grid refinement and coarsening in the simulation good matchs were gained. Based on the results of the simulation the reserve distribution, percent of reserve produced in various space and the natural energy were analyzed. The fluid was storaged in the fractures and vugs mostly and more than 90% the produced oil came from the systems. The energy belonged to the active one. The results of simulation accorded with the fact and showed the validity and practicability the research and the simulator.
塔河油田奥陶系碳酸盐岩油藏的地质研究表明,其储层中发育着很多大型的溶蚀洞、缝,储层的平面展布呈现出极度的非均质性,形成了典型的缝洞型碳酸盐岩油藏,根据各种孔隙介质在储层中的组合,将储层分为了溶洞型、裂缝-溶洞型和裂缝型三类;研究表明溶洞储层的发育和构造位置、裂缝的发育、潜水面和风化面的位置等因素有关;多期充注的油气成藏模式导致了流体复杂的赋存状态,由此提出了所谓的"瓶子模型",解释生产过程中油水界面的变化;特殊的储集空间类型和流体分布特征导致油田在开发过程中表现出很大的不确定性和含水变化的复杂性,为了合理的解释油气田开发过程中的动态特征,提出了"缝洞单元"的概念,并制定了"缝洞单元"纵横向划分的基本原则和依据及划分方法,并对"缝洞单元"进行了分类和评价;基于地质特征和流体在其中流动规律的研究,提出了缝洞型碳酸盐岩油藏的数值模拟综合解决方案,通过模拟单元的选择、流动类型和参数的等效,建立了三重介质油藏三维三相数值模拟模型,采用不完全LU分解预处理共轭梯度法进行了求解;在塔河油田4区精细油藏描述的基础上,将各种类型的孔隙空间进行了归类组合,建立了S48单元的地质模型;通过对油井生产动态进行分析研究,建立了两类和油井地质、生产动态相对应的单井模型;最后应用三重介质油藏数值模拟软件对单井模型和S48单元进行了数值模拟,通过局部加密和粗化等技术模拟流体流动规律,取得了很好的拟合效果;结合数值模拟结果,分析了各种介质中的储量分布、储量产出的百分比以及地层的能量,认为塔河油田缝洞型油藏中流体绝大多数储集于缝洞系统之中,所产出流体90%以上也来自于缝洞系统,其底水能量属于较充足的类型;模拟结果和油田实际情况符合较好,说明了地质研究和油藏数值模拟研究的正确性。
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The geology research of carbonate reservoirs in Ordovician of Tahe oilfield showed that many large dissolved vugs and fractures were developed. The spread of the reservoir take on a very heterogeneous state. And the typical fractured-vuggy reservoirs was formed. According to the combination of the various spaces, the formation was divided into vuggy formation, fractured-vuggy formation and fractured formation. The research showed that development of the vug is relevant to the its position on the structure, the fractures, the water surface and the weathering surface. Multi-phase charge and recharge of the oil in the reservoirs resulted in the complexity of the fluid distribution. So the"Bottle Model"was brought forward to explain the movement of the water-oil contact. The special storage space and the complex fluid distribution lead to the unstability of the production and the complexity of the water cut. In order to explain the characteristic of the fracture-vug unit was brought forward and the basic principle and method of the partition of the fracture-vug unit was formed. The classification and evaluation of the units were performed according the reserve and energy. Based on the research of geology characteristic and the fluid flow in the reservoir the comprehensive numerical simulation plan of the fractured-vuggy reservoirs were established. Through the selection of the simulation unit, fluid flow type and parameter equivalent the triple media reservoir simulation model was established. Considering the practical application the model was resolved by the DKR decomposition conjugate grads method. Based on the fine reservoir description of Dsitrict IV of the Tahe oilfield the various space type were classified and combined together. The geology model of Unit S48 was constructed. Two typical single well model was established according to the geology and the dynamic phenomena. Finally the single well model and the Unit S48 were simulated by the triple media reservoir simulator. Via the local grid refinement and coarsening in the simulation good matchs were gained. Based on the results of the simulation the reserve distribution, percent of reserve produced in various space and the natural energy were analyzed. The fluid was storaged in the fractures and vugs mostly and more than 90% the produced oil came from the systems. The energy belonged to the active one. The results of simulation accorded with the fact and showed the validity and practicability the research and the simulator.
塔河油田奥陶系碳酸盐岩油藏的地质研究表明,其储层中发育着很多大型的溶蚀洞、缝,储层的平面展布呈现出极度的非均质性,形成了典型的缝洞型碳酸盐岩油藏,根据各种孔隙介质在储层中的组合,将储层分为了溶洞型、裂缝-溶洞型和裂缝型三类;研究表明溶洞储层的发育和构造位置、裂缝的发育、潜水面和风化面的位置等因素有关;多期充注的油气成藏模式导致了流体复杂的赋存状态,由此提出了所谓的&瓶子模型&,解释生产过程中油水界面的变化;特殊的储集空间类型和流体分布特征导致油田在开发过程中表现出很大的不确定性和含水变化的复杂性,为了合理的解释油气田开发过程中的动态特征,提出了&缝洞单元&的概念,并制定了&缝洞单元&纵横向划分的基本原则和依据及划分方法,并对&缝洞单元&进行了分类和评价;基于地质特征和流体在其中流动规律的研究,提出了缝洞型碳酸盐岩油藏的数值模拟综合解决方案,通过模拟单元的选择、流动类型和参数的等效,建立了三重介质油藏三维三相数值模拟模型,采用不完全LU分解预处理共轭梯度法进行了求解;在塔河油田4区精细油藏描述的基础上,将各种类型的孔隙空间进行了归类组合,建立了S48单元的地质模型;通过对油井生产动态进行分析研究,建立了两类和油井地质、生产动态相对应的单井模型;最后应用三重介质油藏数值模拟软件对单井模型和S48单元进行了数值模拟,通过局部加密和粗化等技术模拟流体流动规律,取得了很好的拟合效果;结合数值模拟结果,分析了各种介质中的储量分布、储量产出的百分比以及地层的能量,认为塔河油田缝洞型油藏中流体绝大多数储集于缝洞系统之中,所产出流体90%以上也来自于缝洞系统,其底水能量属于较充足的类型;模拟结果和油田实际情况符合较好,说明了地质研究和油藏数值模拟研究的正确性。
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According to the energy conservation theory, BOM and CSIM4 were coupled. The BOM has no treatment on transmission solar radiation, which is of great importance when the model is adapted to Arctic Ocean. So the treatment was introduced to BOM. Through numerical test on different lead albedos, it was found that sea ice thickness is not so sensitive to lead albedo, which may be contribute to the lead occupies little ratio within multiyear sea ice pack. The reason of summer over-melt of arctic sea ice is the NCEP reanalysis downward solar radiation being larger than its reality. Then the arctic sea ice climate variability was simulated. Results showed that: simulated ice thickness change is in accord with the submarine investigated mean sea-ice draft changes. Simulated annually maximum ice thickness along the Eurasian continental oceans are closely related to the observed ones. The long-term mean simulated ice motion has the same features of the SSM/I derived ice motion. Sea ice extents in differential sub-regions have same trends comparing to the satellite passive-microwave data derived ones. Simulated ice concentration is closely related to the observed in the Arctic sub-regions. Sea ice flux through the Fram Strait involves ice concentration, motion and thickness. It is a composite criterion for sea ice model evaluation. The simulated ice area and volume export through the strait accord with the satellite derived or statistically reconstructed ones.(5) The simulated ice thickness climate variability and mean sea surface current of the coupled model were analyzed, results showed: the total ice volume in the Arctic Ocean has a significant decreasing trend. The volume variability is of a 10-year timescale oscillation, with two major periods of 12-13a and 18-20a. Mean ice thickness in the arctic sub-seas has different tendencies. It has an increasing trend in the Barents-Kara Sea and Baffin Bay-Labrador Sea, and decreasing in the others. The characteristic time scale of 7-10a wherein the river discharges leads the Fram Strait ice volume export is about the period that river water takes to be conveyed across the Arctic Ocean.(6) Using the simulated ice distribution in the Arctic Ocean and China precipitation, air temperature and SST in tropical key regions, the climate teleconnection were studied. Result showed: When the mean sea ice thickness is large in the central Arctic Ocean and Chukchi-Beaufort Sea , and small in the Barents-Kara Sea and Baffin Bay-Labrador Sea , the precipitation in South China, Tibetan Plateau, and the north part of Northeastern China are always smaller than normal, and v. v. When the mean ice thickness is small in CA, BC, East Siberian Sea and Greenland-Iceland-Norwegian Sea , and large in BL, The air temperature in north-eastern China, the southern of Tibetan Plateau, and Hainan Island, are always lower than normal, and v. v. In addition, when the sea ice is thick in BC and BL, the SST is larger in the middle and eastern Pacific Ocean, and is smaller in the tropical Southeastern Indian Ocean.
由于BOM没有考虑透射太阳辐射的物理过程,研究表明透射太阳辐射对北冰洋的能量收支起到重要作用,因此在BOM模式中引入了对透射太阳辐射的处理;通过对不同水道反照率的数值试验表明海冰厚度对水道反照率的敏感性不强,可能与海冰区水道面积占的比率很小有关;而模式模拟的北极海冰夏季&过度融化&主要源于NCEP再分析资料提供了偏大的太阳短波辐射;对北极海冰的气候变率进行了模拟研究,结果表明:模拟的海冰厚度变化与潜艇探测的海冰吃深度变化具有一致性;模拟和观测的亚欧大陆沿海的年内最大海冰厚度有很好的相关;模拟的海冰移速与长期平均的卫星反演的海冰移速具有相同的速度分布特征;模拟的各个海区海冰面积的变化趋势与卫星反演资料分析的结果基本一致;模拟与观测的主要海洋分区的海冰密集度具有很好的相关:弗瑞姆海峡的海冰体积和面积的输送涉及到海冰密集度、厚度和移动速度,是判断模式模拟能力的一个综合的指标,模式模拟的结果与卫星反演或重建的面积输送、体积输送具有很好的一致性;(5)分析了模拟的北极海冰厚度的气候变率及气候平均表层海流场,结果表明:北极海冰的总体积有显著减少的趋势,北极海冰总体积的变化具有10a际尺度振荡的特点,存在18-20a和12-13a两个主周期;北极海冰的平均厚度在各个海区的变化趋势不同,在巴伦支—喀拉海和巴芬湾—拉布拉多海地区海冰厚度有显著的增加趋势,而其它海区存在减少的趋势;通过对模拟的气候平均表层海流的分析表明,北极河流流量超前弗瑞姆海峡海冰流量7-10年的特征时间尺度与表层海流的气候分布存在着必然联系:(6)利用模拟结果以及中国降水、气温和热带关键区SST资料,讨论了北极各海区海冰平均厚度与中国降水、气温以及热带关键区SST的关系,结果表明:在北极中心海区和楚科奇—波弗特海海冰厚度偏大,在巴伦支—喀拉海以及巴芬湾—拉布拉多海海冰厚度偏小,则中国降水在华南地区、青藏高原和东北北部降水偏少,反之相反;在北极中心海区、东西伯利亚海、楚科奇—波弗特海以及格陵兰海海冰厚度偏小,在巴芬湾—拉布拉多海海冰厚度偏大,则在中国东北地区、高原南部地区和海南岛附近气温偏低,反之相反;另外,北极楚科奇—波弗特海和巴芬湾—拉布拉多海海冰厚度偏大时,在热带中东太平洋海温偏高,而在热带东南印度洋海温偏低。
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The results show that the RIEMS can simulate the pattem and seasonal cycle of standard deviation of surface temperature and precipitation.
第一部分是检验RIEMS模式对东亚地区十年平均气候状况的模拟能力,结果表明,RIEMS模式能够较好地模拟出不同季节温度(包括平均温度、最高温度、最低温度)的空间分布和季节变化以及不同区域温度的年变化;无论是平均温度,还是最高温度、最低温度,模式模拟季平均和月平均温度与观测之间偏差大约一般在1-2℃,这与IPCC(2001)报告中报告的在区域尺度10〓-10〓KM,季平均温度偏差在1-2℃较为一致;模式能够较好地模拟降水的空间分布特征和季节变化以及不同区域平均降水的年变化,同时,也能够较好地模拟出雨带季节性的演变,但模拟的雨带位置较观测偏北,大约为2-3纬度;就季节而言,模式模拟最好的季节为冬季,较差的季节为夏季;模式基本上能够较好的模拟出不同季节平均海平面气压场的空间分布以及东亚地区的湿润和干旱分布规律的干旱指数的空间分布。
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The first part is to assess whether RIEMS has ability to reproduce ten-years averaged mean climate in East Asia.The results demonstrate that RIEMS is capable to reproduce the patterns and seasonal cycle of temperature(mean temperature/maximal temperature/minimal temperature), precipitation, sea level pressure and arid index as well as the rain belt evolution.The simulated seasonal and monthly averaged temperature biases are generally in the range of 1-2℃,which are consistent with IPCC(200 1)report. Although model can reproduce the seasonal cycle and time evolution of precipitation, the simulated rain belt has northwards shift of 2-3 degree.
第一部分是检验RIEMS模式对东亚地区十年平均气候状况的模拟能力,结果表明,RIEMS模式能够较好地模拟出不同季节温度(包括平均温度、最高温度、最低温度)的空间分布和季节变化以及不同区域温度的年变化;无论是平均温度,还是最高温度、最低温度,模式模拟季平均和月平均温度与观测之间偏差大约一般在1-2℃,这与IPCC(2001)报告中报告的在区域尺度10〓-10〓KM,季平均温度偏差在1-2℃较为一致;模式能够较好地模拟降水的空间分布特征和季节变化以及不同区域平均降水的年变化,同时,也能够较好地模拟出雨带季节性的演变,但模拟的雨带位置较观测偏北,大约为2-3纬度;就季节而言,模式模拟最好的季节为冬季,较差的季节为夏季;模式基本上能够较好的模拟出不同季节平均海平面气压场的空间分布以及东亚地区的湿润和干旱分布规律的干旱指数的空间分布。
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In Yunlin Hsinhsing industrial District land reclamation project, sand filled Geotubes are used to form the segmented breakwaters along the district perimeter and stone blocks are used to protect the shoreline and foreshore. This research use computer simulation to analyze the production rate of establishment of Geotubes for the aforementioned project.
因此本研究利用电脑模拟技术运用在砂肠围堤工程,并以新兴工业区为实际模拟案例建立砂肠围堤施工CYCLONE模型,利用模拟分析技术配合COST电脑模拟程式进行模拟分析,再以实际施工历史数据与电脑模拟做相互验证,检核模拟结果是否与现场符合,进而模拟以不同砂肠轮进长度的组合之生产力,比较出最佳砂肠长度的组合。
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There are some questions such as forest fire model selection, forest fire model updating, verifying simulation accuracy and so on in traditional forest fire spreading system. Study purpose is to build an innovative forest fire spreading simulation system based on DDDAS in this paper. The system can increase precision of forest fire spreading simulation by model base, model selection, model updating and so on. It can provide a strategic decision for forest fire save and new technologies demonstration for other related field of research. The research encompasses several major topics:(1) This paper brings up the term of dynamic data driven forest fire spreading simulation system and supplies new research approach and thought for forest fire spreading simulation study. The system framework was brought.
本研究针对传统林火模拟过程中存在的模型手动选择难度大、模型修正数据获取效率低、模拟精度验证困难等问题,以DDDAS为林火蔓延模拟研究的技术范式,提出林火蔓延模拟全新的技术框架体系,解决模拟系统建设过程中的模型库建设与管理、模型适宜性选择、模型自适应修正、模拟过程实时验证等关键技术,建立林火扩散模拟和实际林火发展之间相互协作、共生的林火扩散动态模拟系统;提高林火蔓延模拟精度,将林火蔓延模拟真正应用到林火扑救指挥过程当中,在实践上为林火扑救指挥提供决策支持,在理论上为相关领域的空间扩散模拟研究提供新的思路和技术范式。
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It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.
从鲍尔点的形成原理出发,分析对称连杆曲线上鲍尔点的产生条件,提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。
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The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.
集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品,年生产总值3000万美元,产品价廉物美、选料上乘、质量保证,深受国内外客户的青睐
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The eˉtiology of hemospermia is complicate,but almost of hemospermia are benign.
血精的原因很,以良性病变为主。