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蓖麻拟三系配套技术的研究 被引量:17
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作者 张维锋 梁一刚 《作物学报》 CAS CSCD 北大核心 1999年第3期392-395,共4页
在研究雌株蓖麻遗传规律的基础上,利用其人工诱导条件下可发生育性逆转的特性,创建了核遗传型模拟三系配套的杂种优势利用技术体系,育成了雌株率达100%的蓖麻雌性系8937F及其保雌系,并培育出高产杂交种汾蓖5号、6号等投入大面积生产试种.
关键词 雌株蓖麻 核遗传 拟三系 杂交种 蓖麻 育种
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THE SYSTEM SIMULATION OF THREE-DIMENSIONAL RADAR 被引量:3
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作者 ZhangWei XiangJingcheng WangXuegang 《Journal of Electronics(China)》 2004年第5期407-412,共6页
To provide a test platform for Electronic Warfare (EW) system, it is needed to simulate the radar received Intermediate Frequency (IF) signals and radar system functions.This letter gives a description of a radar syst... To provide a test platform for Electronic Warfare (EW) system, it is needed to simulate the radar received Intermediate Frequency (IF) signals and radar system functions.This letter gives a description of a radar system simulation software developed for frequencyphase scanning three-dimensional (3-D) radar. Experimental results prove that the software could be used for system evaluation and for training purposes as an attractive alternative to real EW system. 展开更多
关键词 System simulation Electronic Warfare(EW) Three-dimensional(3-D) radars Intermediate Frequency (IF) signals
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Mitigation of floor heave in West Kentucky Coal Mine 被引量:4
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作者 Perry Kyle Bradley Joel +1 位作者 Unrug Kot Klimek Mark 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第3期521-525,共5页
A West Kentucky mine operation in No. 11 seam encountered floor heave, due to the localized increase in the thickness of the fireclay mine floor. Floor heave has overridden seals installed in two mined out panels. The... A West Kentucky mine operation in No. 11 seam encountered floor heave, due to the localized increase in the thickness of the fireclay mine floor. Floor heave has overridden seals installed in two mined out panels. The third seal's location was planned for isolating that area from the Mains. A plan of support has been developed to prevent repetition of the floor heave and related problems outby the seals. The applied ground control measures were successful. An attempt of a 3D numerical modeling was made; thus, it would match the observed behavior of the mine floor and could be used as a design tool in similar conditions. The paper describes sequence of events, an applied mitigation ground control system, and the first stage of numerical modeling. 展开更多
关键词 Floor heave Presplit Secondary support Modeling
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Quantitative identification of relatively highlevel radioactive sandstone in the Upper Triassic Yanchang Formation of the Ordos Basin, China 被引量:2
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作者 Li Ya-Jun Zhang Xiao-Li Yan Yuan-Zi 《Applied Geophysics》 SCIE CSCD 2019年第3期314-320,395,396,共9页
Most relatively high-level radioactive sandstone(HRSS)reservoir has considerable oil(or gas)resource potential.HRSS is often wrongly identified due to its similar logging response characteristics as mudstone,which lea... Most relatively high-level radioactive sandstone(HRSS)reservoir has considerable oil(or gas)resource potential.HRSS is often wrongly identified due to its similar logging response characteristics as mudstone,which leads to the omission of effective reservoirs.In this paper,a quantitative identification method for HRSS is proposed after the analyzing of the response characteristics and relationship between spontaneous potential log and natural gamma-ray log in conventional sandstone and mudstone strata.Take the Upper Triassic Yanchang Formation in Ordos Basin as an example:the responses of spontaneous potential log and the responses of natural gamma-ray log are synchronized and positively correlated in conventional sandstone and mudstone strata,but they are not synchronized in HRSS.Quantitative identification of HRSS was realized based on this synchronization feature,and a"virtual compensation"of natural gamma-ray log was performed.At the same time,logging evaluation method about HRSS has been discussed.The final results shows that this identification method work effectively,and can reduce the misjudgment and omission of effective reservoirs. 展开更多
关键词 relatively high-level radioactive sandstone quantitative identification virtual compensation of radioactivity Ordos Basin Upper Triassic Yanchang Formation
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Study on Visualization of Virtual City Model Based on Internet
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作者 JINBaoxuan BIANFuling ZUOXiaoqing WANGFangxiong 《Geo-Spatial Information Science》 2005年第2期115-121,共7页
With the rapid development of computer graphics, distributed-computing and Internet, it is possible to achieve Internet-based virtual city. This paper dwells on the method of the terrain and its feature modeling and c... With the rapid development of computer graphics, distributed-computing and Internet, it is possible to achieve Internet-based virtual city. This paper dwells on the method of the terrain and its feature modeling and complex entity modeling in the virtual city. Then, discusses the method for Internet-based virtual city 3D visualization and the design of the Browser/Server architecture of the system of virtual city in the network environment. Finally, Java and Java 3D are used to show an experiment example, and the related conclusion about Internet-based virtual city 3D displaying and the client-side interactive operation is given. 展开更多
关键词 distributed-computing virtual city modeling 3D visualization Java 3D
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Research on an Integrated Modeling Method of Virtual Ship Assembly 被引量:1
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作者 袁华 赵耀 严俊 《Journal of Marine Science and Application》 2011年第4期447-455,共9页
A new method of virtual ship assembly modeling which integrates ship three-dimensional design and ship construction planning was described in this paper. A workflow model of simulation modeling based on the virtual sh... A new method of virtual ship assembly modeling which integrates ship three-dimensional design and ship construction planning was described in this paper. A workflow model of simulation modeling based on the virtual ship assembly process was also established; furthermore, a method of information transformation between the ship three-dimensional design and ship construction plan was formulated. To meet the requirements of information sharing between different systems in the ship virtual assembly, a simulation database was created by using the software engineering design method and the relational data model. With the application of this database, the information of ship three-dimensional design, construction planning, and virtual assembly can be integrated into one system. Subsequently, this new method was applied as a tool to simulate the virtual assembly of a ship, and the results guarantee its rationality and reliability. 展开更多
关键词 ship virtual assembly simulation modeling workflow model simulation database three-dimensional design construction planning
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Mechanism of zonal disintegration phenomenon in enclosing rock mass around deep tunnels
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作者 吴昊 郭志昆 +2 位作者 方秦 张亚栋 柳锦春 《Journal of Central South University》 SCIE EI CAS 2009年第2期303-311,共9页
In order to study the mechanism of the zonal disintegration phenomenon(ZDP),both experimental and theoretical investigations were carried out.Firstly,based on the similarity law,gypsum was chosen as equivalent materia... In order to study the mechanism of the zonal disintegration phenomenon(ZDP),both experimental and theoretical investigations were carried out.Firstly,based on the similarity law,gypsum was chosen as equivalent material to simulate the deep rock mass,the excavation of deep tunnel was modeled by drilling a hole in the gypsum models,two circular cracked zones were measured in the model,and ZDP in the enclosing rock mass around deep tunnel was simulated in 3D gypsum model tests.Secondly, based on the elasto-plastic analysis of the stressed-strained state of the surrounding rock mass with the improved Hoek-Brown strength criterion and the bilinear constitutive model,the maximum stress zone occurred in vicinity of the elastic-plastic interface due to the excavation of the deep tunnel,rock material in maximum stress zone is in the approximate uniaxial loading state owing to the larger tangential force and smaller radial force,the mechanism of ZDP was explained,which lay in the creep instability failure of rock mass due to the development of plastic zone and transfer of the maximum stress zone within the rock mass.Thirdly,the analytical critical depth for the occurrence of ZDP was obtained,which depended on the mechanical indices and stress concentration coefficient of rock mass. 展开更多
关键词 zonal disintegration phenomenon (ZDP) block-hierarchical structure deep tunnel creep instability stress concentration coefficient
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Virtual State Estimation Calculator Model for Three Phase Power System Network
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作者 Samson Raja Simson Sundar Ravichandran +1 位作者 Amudha Alagarsamy Nithiyananthan Kannan 《Journal of Energy and Power Engineering》 2016年第8期497-503,共7页
The main objective of this research work is to develop a simple state estimation calculator in LabView for three phase power system network. LabView based state estimation calculator has been chosen as the main platfo... The main objective of this research work is to develop a simple state estimation calculator in LabView for three phase power system network. LabView based state estimation calculator has been chosen as the main platform because it is a user friendly and easy to apply in power systems. This research work is intended to simultaneously acclimate the power system engineers with the utilization of LabView with electrical power systems. This proposed work will discuss about the configuration and the improvement of the intelligent instructional VI (virtual instrument) modules in power systems for state estimation solutions. In the proposed model state estimation has been carried out and model has been developed such that it can accommodate the latest versions of state estimation algorithm. 展开更多
关键词 State estimation LABVIEW three phase power system network.
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