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新高考下语篇型语法填空设空分析及解题策略
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作者 瞿婧 《试题与研究(教学论坛)》 2018年第13期33-34,共2页
2014年教育部考试中心对高考英语试 卷结构进行了新的调整,启用了语篇型语法填空题 取代了沿用多年的传统的测试语用、语法基础知识 的语法单项选择题。高考英语新题型语篇型语法填 空题着重在语篇层面考查考生的语用能力,强调语 法知... 2014年教育部考试中心对高考英语试 卷结构进行了新的调整,启用了语篇型语法填空题 取代了沿用多年的传统的测试语用、语法基础知识 的语法单项选择题。高考英语新题型语篇型语法填 空题着重在语篇层面考查考生的语用能力,强调语 法知识在实际语言中的灵活运用。本文针对高考英 语试卷中的语篇型语法填空题型,阐述了该题型的 基本要求和特点,从考点分布出发,探讨语篇型语法 填空设空规律及应对策略,从而帮助学生形成有效 的语法填空解题策略。 展开更多
关键词 语篇型语法填 设空分析和解题策略 基于语篇的语言教学
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综放工作面撤除后沿空留设切眼的方法
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作者 杨钟瑜 王元明 +1 位作者 刘汉荣 郝朝宏 《煤矿开采》 1999年第4期83-83,85,共2页
介绍了综放工作面拆除后沿空留设切眼的方法和取得的经济效益。
关键词 综放面 沿切眼 经济效益 备拆除
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沿空留设上山在倾斜分层采煤法中的应用 被引量:1
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作者 王福红 何德强 《河北煤炭》 2003年第3期15-16,共2页
介绍了厚煤层走向长壁倾斜分层采煤法中沿空留设上山,减少上山煤柱的留设,提高了回采率,降低了工作面收尾时大量的坑木消耗,改善了上山受力状况,降低了巷道维修费用,取得了较好的经济效益。
关键词 沿上山 推透上山 回采工艺 厚煤层走向长壁倾斜分层采煤法 煤柱 回采率 巷道维修费用 经济效益
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“沿空设巷”在采煤工作面过小构造的使用与效果
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作者 卢信堂 《煤炭科技》 1999年第3期43-44,共2页
介绍了旗山煤矿13105工作面使用“沿空设巷”过断层的方法与效果,说明在高档普采、炮采工作面采煤过程中遇地质构造时,可以避开受构造影响部分进行采煤。
关键词 沿 地质构造 特殊支护 缩面生产 采煤面
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Analysis and Modeling of the Central Air-Conditioning System in Intelligent Buildings 被引量:6
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作者 郭巧 徐庆伟 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期295-297,共3页
The central air conditioning system in an intelligent building (IB) was analyzed and modeled in order to perform the optimization scheduling strategy of the central air conditioning system. A set of models proposed ... The central air conditioning system in an intelligent building (IB) was analyzed and modeled in order to perform the optimization scheduling strategy of the central air conditioning system. A set of models proposed and a type of periodically autoregressive model (PAR) based on the improved genetic algorithms (IGA) were used to perform the optimum energy saving scheduling. The example of the Liangmahe Plaza was taken to show the effectiveness of the methods. 展开更多
关键词 intelligent building analysis and modeling central air conditioning energy saving
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Spatial Planning and Designing for Campuses in the New Era 被引量:1
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作者 卢俊 《Agricultural Science & Technology》 CAS 2017年第7期1332-1335,共4页
Current education system reform poses unprecedented opportunities for higher schools. The research proposed components and organization types for uni- versity/college spatial configuration based on campus spaces at ho... Current education system reform poses unprecedented opportunities for higher schools. The research proposed components and organization types for uni- versity/college spatial configuration based on campus spaces at home and abroad. In the background of sustainable design, the research took urban space design as references in order to explore effects of higher education theory on campus space design, analyze campus development trend and spatial configuration, as well as pro- vide references for massive urban university/college projects" construction and re-de- velopment. 展开更多
关键词 Urban design Campus planning Campus space
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Effects of the profile of a supercavitating vehicle's front-end on supercavity generation 被引量:2
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作者 张博 张宇文 袁绪龙 《Journal of Marine Science and Application》 2009年第4期323-327,共5页
The authors designed three different front profiles for supercavitating vehicles based on cavity theory and the Granville streamlined equation are designed. Experiments were done using these front profiles in the Nort... The authors designed three different front profiles for supercavitating vehicles based on cavity theory and the Granville streamlined equation are designed. Experiments were done using these front profiles in the Northwestern Polytechnical University high-speed water tunnel. The experiments indicated that the critical volume of gas required for supercavitation is affected by the axial distribution of the front-end's slope. The experimental data showed critical gas flow rates required for the three designs were less than rood-l, with the greatest decrease 24%. The experimental results also showed the supercavitation generation speeds of the models were faster than mod-1 by up to 32.4%. This verifies that the front profile of a supercaviting vehicle effects supercavity generation speed and critical gas flow rates. The smaller the changes in axial distribution of pressure, the higher the supercavity generation speed. The smaller the changes in curvature distribution of axial, the smaller the critical gas flow rates. 展开更多
关键词 CAVITATION supercavitating vehicle volumetric gas flow rate front profile supercavitation generation speed
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Spatial structural analysis of main saddle for single tower spatial cable self-anchored suspension bridge
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作者 李建慧 李爱群 +1 位作者 袁辉辉 李喜平 《Journal of Southeast University(English Edition)》 EI CAS 2009年第3期372-375,共4页
Based on the engineering background of the Jiangxinzhou Bridge in Nanjing, issues related to the spatial main saddle of the self-anchored suspension bridge are studied. The refinement finite element model is establish... Based on the engineering background of the Jiangxinzhou Bridge in Nanjing, issues related to the spatial main saddle of the self-anchored suspension bridge are studied. The refinement finite element model is established by the secondary development technology based on the platform of the general finite element program, and a reasonable load pattern is used in its spatial structural analysis, by which its path of force transference and stress distribution are obtained. Matched with the spatial main cable, the tangency point correction method is also discussed. The results show that the lateral wall stress of the saddle groove is higher than the stress within the wall due to the role of lateral forces in the finished bridge state; the horizontal volume force of the main cable can generate a gradient distributed vertical extrusion pressure on the saddle clamping device and the main saddle body; the geometric nonlinear effect of the self- anchored suspension bridge cable system in the construction process is significant, which can be reflected in the spatial tangent point position of the main cable with the main saddle changes a lot from free cable to finished cable. 展开更多
关键词 self-anchored suspension bridge finite element main saddle spatial cable structural design
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Roles and Functions of Tourism Destinations in Tourism Region of South Anhui:A Tourist Flow Network Perspective 被引量:9
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作者 LIU Fajian ZHANG Jinhe +3 位作者 ZHANG Jie CHEN Dongdong LIU Zehua LU Song 《Chinese Geographical Science》 SCIE CSCD 2012年第6期755-764,共10页
Theoretic and practical significance has been highlighted in the research of the roles and functions of destinations,as destinations are restricted by the spatial structure based on tourist flow network from the persp... Theoretic and practical significance has been highlighted in the research of the roles and functions of destinations,as destinations are restricted by the spatial structure based on tourist flow network from the perspective of relationship.This article conducted an empirical analysis for Tourism Region of South Anhui(TRSA) and revealed the necessity and feasibility of studying the roles and functions of destinations from tourist flow network's perspective.The automorphic equivalence analysis and centrality analysis were used to classify 16 destinations in TRSA into six role types:tourist flow distribution center,hub of tourist flows,passageway destination,common touring destination,attached touring destination,and nearly isolated destination.Some suggestions were given on suitable infrastructure construction and destinations service designs according to their functions in network.This destination role positioning was based on tourist flow network structure in integral and macroscopic way.It provided an important reference for the balanced and harmonious development of all the destinations of TRSA.In addition,this article verified the applicability of social network analysis on tourist flow research in local scale,and expanded this method to destination role and function positioning. 展开更多
关键词 tourist flow network equivalence model ROLES FUNCTIONS centrality analysis Tourism Region of South Anhui
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Spatial spillover effects of transport infrastructure on regional economic growth
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作者 刘南 陈远高 周庆明 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期33-39,共7页
Spatial spillover effects,either positive or negative,of transport infrastructure,highways/expressways,etc.,on regional economic growth are proposed.Using the panel data for 11 cities of Zhejiang province from 1994 to... Spatial spillover effects,either positive or negative,of transport infrastructure,highways/expressways,etc.,on regional economic growth are proposed.Using the panel data for 11 cities of Zhejiang province from 1994 to 2003,a spatial production function is applied to examine the spatial spillovers which can be generated as a positive output spillover from the transport infrastructure between neighboring cities.Some spatial weighted matrices are adopted to define different neighboring cities to measure how easily factors or economic activities can migrate between regions.The estimation results show that the output elasticity of the highway infrastructure in 11 cities are all insignificant at a 5% significance level;hence,highway infrastructure in a region cannot explain the same region's economic growth.On the other hand,the highway infrastructure of other contiguous regions has positive spillover effects on a same region's economic growth. 展开更多
关键词 transport infrastructure HIGHWAY economic growth effects of spatial spillovers spatial weighted matrix
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Waterfront Spatial Design from the Perspective of Sponge City 被引量:2
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作者 陈坤 《Agricultural Science & Technology》 CAS 2017年第6期1095-1096,1125,共3页
Due to environmental awareness, demand for watercourse landscape eco- function is growing domestically. However, flood control and drainage are the only focuses, and the rest functions of water course are slighted. Be... Due to environmental awareness, demand for watercourse landscape eco- function is growing domestically. However, flood control and drainage are the only focuses, and the rest functions of water course are slighted. Besides, cross-section biodiversity is falling and wetland self-cleaning capacity is impairing, resulting from river limitation on riverbed, making a straight river bend and revetment. So, water course has to be managed from ecology, economy, culture and social effect, to re- store natural river function and meet human demands. And to return to nature and people first would be the general principles. 展开更多
关键词 Sponge city Waterfront area Planning and designing
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Space Drive Propulsion Principle from the Aspect of Cosmology 被引量:2
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《Journal of Earth Science and Engineering》 2013年第6期379-392,共14页
This paper describes the propulsion principle using the concept of space drive and the pressure of the field induced by local rapid expansion of space based on the latest cosmology. Assuming that space vacuum is an in... This paper describes the propulsion principle using the concept of space drive and the pressure of the field induced by local rapid expansion of space based on the latest cosmology. Assuming that space vacuum is an infinite continuum, the propulsion principle utilizes the pressure field derived from the geometrical structure of space, by applying both continuum mechanics and general relativity to space. The propulsive force is a pressure thrust that arises from the interaction of space-time around the spaceship external environment and the spaceship itself; the spaceship is propelled by the pressure used against the space-time structure. As is well known in cosmology, the expansion rule of the universe is governed by the Friedman's equations and the Robertson-Walker metric. In this time, the propulsion principle of space drive is introduced from another angle (cosmology), that is, the pressure of the field induced by local expansion of space is completely considered in the propulsion principle. 展开更多
关键词 Space drive PROPULSION COSMOLOGY expanding .universe Friedman's equation Robertson-Walker metric de Sitteruniverse inflation.
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Spatial Process of Green Infrastructure Changes Associated with Rapid Urbanization in Shenzhen,China 被引量:6
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作者 CHANG Qing LI Shuangcheng +2 位作者 WANG Yanglin WU Jiansheng XIE Miaomiao 《Chinese Geographical Science》 SCIE CSCD 2013年第1期113-128,共16页
Through a case study of Shenzhen City,China,this study focused on a quantitative method for analyzing the spatial processes involved in green infrastructure changes associated with rapid urbanization.Based on RS,GIS a... Through a case study of Shenzhen City,China,this study focused on a quantitative method for analyzing the spatial processes involved in green infrastructure changes associated with rapid urbanization.Based on RS,GIS and SPSS statistics software,the approach includes selection of the square analysis units and representative landscape metrics,quantification of the change types of landscape metrics in all analysis units through two indices and hierarchical cluster analysis of the above analysis units with different landscape metric change types(i.e.spatial attributes).The analyses verify that there is a significant sequence of continuous changes in green infrastructure in Shenzhen.They are the perforation,the segmentation,the fragmentation,the evanescence and the filling-in processes,which have a good spatio-temporal correspondence with urbanization and reflect the synthetic influence of urban planning,government policies and landforms.Compared with other studies on quantifying the spatial pattern,this study provides an alternative probe into linking the spatial pattern to spatial processes and the corresponding ecological processes in the future.These spatio-temporal processes offer many opportunities for identifying,protecting and restoring key elements in an urban green infrastructure network for areas in the early stages of urbanization or for non-urbanized areas. 展开更多
关键词 spatial process landscape metrics dynamic change green infrastructure URBANIZATION
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Investigation on a vertical radial flow adsorber designed by a novel parallel connection method 被引量:10
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作者 Zhengshu Dai Meng Yu +2 位作者 Daozhe Rui Xuejun Zhang Yang Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第3期484-493,共10页
Due to the increasing global demand for industrial gas, the development of large-scale cryogenic air separation systems has attracted considerable attention in recent years. Increasing the height of the adsorption bed... Due to the increasing global demand for industrial gas, the development of large-scale cryogenic air separation systems has attracted considerable attention in recent years. Increasing the height of the adsorption bed in a vertical radial flow adsorber used in cryogenic air separation systems may efficiently increase the treatment capacity of the air in the adsorber. However, uniformity of the flow distribution of the air inside the adsorber would be deteriorated using the height-increasing method. In order to reduce the non-uniformity of the flow distribution caused by the excessive height of adsorption bed in a vertical radial flow adsorber, a novel parallel connection method is proposed in the present work. The experimental apparatus is designed and constructed; the Computational Fluid Dynamics(CFD) technique is used to develop a CFD-based model, which is used to analyze the flow distribution, the static pressure drop and the radial velocity in the newly designed adsorber. In addition, the geometric parameters of annular flow channels and the adsorption bed thickness of the upper unit in the parallelconnected vertical radial flow adsorber are optimized, so that the upper and lower adsorption units could be penetrated by air simultaneously. Comparisons are made between the height-increasing method and the parallel connection method with the same adsorber height. It is shown that using the parallel connection method could reduce the difference between the maximum and minimum radial static pressure drop by 86.2% and improve the uniformity by 80% compared with those of using the height-increasing method. The optimal thickness ratio of the upper and lower adsorption units is obtained as 0.966, in which case the upper and lower adsorption units could be penetrated by air simultaneously, so that the adsorbents in adsorption space could be used more efficiently. 展开更多
关键词 Air separation Purification Vertical radial flow adsorber Flow distribution Optimization
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Multiple-response optimization for melting process of aluminum melting furnace based on response surface methodology with desirability function 被引量:3
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作者 周孑民 王计敏 +2 位作者 闫红杰 李世轩 贵广臣 《Journal of Central South University》 SCIE EI CAS 2012年第10期2875-2885,共11页
To reduce the fuel consumption and emissions and also enhance the molten aluminum quality, a mathematical model with user-developed melting model and burning capacity model, were established according to the features ... To reduce the fuel consumption and emissions and also enhance the molten aluminum quality, a mathematical model with user-developed melting model and burning capacity model, were established according to the features of melting process of regenerative aluminum melting furnaces. Based on validating results by heat balance test for an aluminum melting furnace, CFD (computational fluid dynamics) technique, in association with statistical experimental design were used to optimize the melting process of the aluminum melting furnace. Four important factors influencing the melting time, such as horizontal angle between burners, height-to-radius ratio, natural gas mass flow and air preheated temperature, were identified by PLACKETT-BURMAN design. A steepest descent method was undertaken to determine the optimal regions of these factors. Response surface methodology with BOX-BEHNKEN design was adopted to further investigate the mutual interactions between these variables on RSD (relative standard deviation) of aluminum temperature, RSD of furnace temperature and melting time. Multiple-response optimization by desirability function approach was used to determine the optimum melting process parameters. The results indicate that the interaction between the height-to-radius ratio and horizontal angle between burners affects the response variables significantly. The predicted results show that the minimum RSD of aluminum temperature (12.13%), RSD of furnace temperature (18.50%) and melting time (3.9 h) could be obtained under the optimum conditions of horizontal angle between burners as 64°, height-to-radius ratio as 0.3, natural gas mass flow as 599 m3/h, and air preheated temperature as 639 ℃. These predicted values were further verified by validation experiments. The excellent correlation between the predicted and experimental values confirms the validity and practicability of this statistical optimum strategy. 展开更多
关键词 aluminum melting furnace melting process response surface methodology desirability function multiple response parameter optimization numerical simulation PLACKETT-BURMAN design BOX-BEHNKEN design
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Continuum Mechanics of Space Seen from the Aspect of General Relativity An Interpretation of the Gravity Mechanism 被引量:1
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作者 Yoshinari Minami 《Journal of Earth Science and Engineering》 2015年第3期188-202,共15页
A mechanical structure of space is suggested. On the supposition that a space as vacuum has a physical fine structure like continuum, it enables us to apply a continuum mechanics to the so-called "vacuum" of space. ... A mechanical structure of space is suggested. On the supposition that a space as vacuum has a physical fine structure like continuum, it enables us to apply a continuum mechanics to the so-called "vacuum" of space. A space is an infinite continuum and its structure is determined by Riemannian geometry. Assuming that space is an infmite continuum, the pressure field derived from the geometrical structure of space is newly obtained by applying both continuum mechanics and General Relativity to space. A fundamental concept of space-time is described that focuses on theoretically innate properties of space including strain and curvature. As a trial consideration, gravity can be explained as a pressure field induced by the curvature of space. 展开更多
关键词 General Relativity continuum mechanics CURVATURE strain SPACE-TIME gravity.
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Parametric geometry representations for wind turbine blade shapes 被引量:3
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作者 Chen Jin Zhang Shiqiang +1 位作者 Hou Yi Eecen Peter 《High Technology Letters》 EI CAS 2011年第3期325-332,共8页
Based on the Joukowsky transformation and Theodorsen method, a novel parametric function (shape function) for wind turbine airfoils has been developed. The airfoil design space and shape control equations also have ... Based on the Joukowsky transformation and Theodorsen method, a novel parametric function (shape function) for wind turbine airfoils has been developed. The airfoil design space and shape control equations also have been studied. Results of the analysis of a typical wind turbine airfoil are shown to illustrate the evaluation process and to demonstrate the rate of convergence of the geometric characteristics. The coordinates and aerodynamic performance of approximate airfoils is rapidly close to the baseline airfoil corresponding to increasing orders of polynomial. Comparison of the RFOIL prediction and experimental results for the baseline airfoil generally show good agreement. A universal method for three-dimensional blade integration-" Shape function/Distribution function" is presented. By changing the parameters of shape function and distribution functions, a three dimensional blade can be designed and then transformed into the physical space in which the actual geometry is defined. Application of this method to a wind turbine blade is presented and the differences of power performance between the represented blade and original one are less than 0. 5%. This method is particularly simple and convenient for bodies of streamline forms. 展开更多
关键词 wind turbine AIRFOILS aerodynamic convergence shape function/ distribution function orders of polynomial (OP)
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伦理视阈下的爱情悲剧——托马斯·哈代的《婚宴空设》
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作者 孙洪振 《作家》 北大核心 2014年第05X期87-88,共2页
托马斯·哈代的小说不仅具有极高的艺术审美价值,而且反映了深刻的伦理道德思想。哈代的短篇小说《婚宴空设》是一部深刻刻画维多利亚时期世俗阶级观念的杰作,也是一部描绘主人公尼古拉斯和克瑞斯汀在道德伦理禁锢下的爱情悲剧。本... 托马斯·哈代的小说不仅具有极高的艺术审美价值,而且反映了深刻的伦理道德思想。哈代的短篇小说《婚宴空设》是一部深刻刻画维多利亚时期世俗阶级观念的杰作,也是一部描绘主人公尼古拉斯和克瑞斯汀在道德伦理禁锢下的爱情悲剧。本文运用文学伦理学的批评方法,辅以文本证据,试图揭示造成主人公悲剧的真正原因。 展开更多
关键词 《婚宴 维多利亚时期 伦理
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Theoretical and experimental investigation on optimization of a non-contact air conveyor 被引量:1
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作者 钟伟 黎鑫 +2 位作者 陶国良 路波 香川利春 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第2期353-361,共9页
Air film conveyors equipped with porous pads have been developed to bring the liquid crystal display(LCD) into a non-contact state during transportation process. In this work, a theoretical model including flow proper... Air film conveyors equipped with porous pads have been developed to bring the liquid crystal display(LCD) into a non-contact state during transportation process. In this work, a theoretical model including flow property of porous media and Reynolds equation is established within a representative region in order to optimize the design parameters of a partial porous air conveyor. With the theoretical model, an optimization method using nondominated sorting genetic algorithm – II(NSGA-II) is applied for a two-objective optimization to achieve a minimum air consumption and maximum load capacity. Three Pareto-optimal solutions are selected to analyze the influence of each parameter on the characteristics of the air conveyor, and the results indicate that the position of the porous pads has the most significant impact on the performance and of course must be determined with care. Furthermore, experimental results in terms of the supporting force versus gap clearance show that the optimized air conveyor can greatly improve the load capacity over the normal one, indicating that the optimization method is applicable for practical use. 展开更多
关键词 OPTIMIZATION genetic algorithm porous media air conveyor pressure distribution
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NEW METHOD OF FORMATION DESIGN FOR BOTH GMTI AND INSAR USING DISTRIBUTED SATELLITES 被引量:1
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作者 Yuan Hao Zhou Yinqing Li Jingwen Sun Muhan 《Journal of Electronics(China)》 2007年第6期821-827,共7页
This letter proposes a method for designing a specific formation of satellites where the flying motion only exists in a circle orbit plane of the reference satellite, which means that the orbit eccentricity is zero. T... This letter proposes a method for designing a specific formation of satellites where the flying motion only exists in a circle orbit plane of the reference satellite, which means that the orbit eccentricity is zero. This method combines the Hill equation, the Kepler equation, and the geometrical inea^ing of orbit elements. It creates the redundancy condition to simplify the deducing process, utilizes multiple conditions to solve the orbit elements for the satellite formation, and obtains the analytical relationship of the orbit elements for the formation satellites with the formation parameters and the orbit elements of the reference satellite. Using these formulations, the orbit elements and formation parameters for the formation satellites can be solved for the given orbit elements of the reference satellite. The letter describes the proposed double-ellipse formation for both GMTI and InSAR, and the validity of the formation is demonstrated via simulation. 展开更多
关键词 Synthetic Aperture Radar (SAR) Double-ellipse formation Dual-interferometry Orbit design
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