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粮食安全与食物安全、食品安全词义辨析
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作者 李艳芳 杜为公 徐李 《全国商情》 2014年第14期45-46,共2页
粮食安全是国家安全的重要内容,保障农产品质量和食品安全是考验一国政府执政能力的关键。借助国家安全、国家经济安全的概念,比较粮食安全与食物安全、食品安全的内涵差异,是确定粮食安全定义的基础。
关键词 粮食安全 食品安全 食物安全 词义辨析 国家经济安全 国家安全 农产品质量 执政能力
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NOVEL STRUCTURE FOR DISTRIBUTED NUMERICAL CONTROL 被引量:3
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作者 WangShilong JianYi +1 位作者 LiuFei RobertYoung 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第4期437-440,共4页
Because of an unexpected signal noise within the network or an unpredictedfault with personal computers (PCs), many problems emerge in the implementation of distributednumerical control (DNC) with PCs-based network. T... Because of an unexpected signal noise within the network or an unpredictedfault with personal computers (PCs), many problems emerge in the implementation of distributednumerical control (DNC) with PCs-based network. To solve the problems, an industrial solution ofinvolving the field-bus technology in DNC communicating area is provided. A kind of advancedField-bus, named controller area network (CAN), is originally developed to support cheap and rathersimple automotive applications. However, because of its good performance and low cost, it is alsobeing considered in automated-manufacturing and process control environments to interconnectintelligent devices, such as modem sensors and actuators. Recently it creates a new role for CANBusin DNC that brings new thinking to DNC. CAN is used as the network platform for connecting machinetools to share information with each other reliably. Additionally, thanks to also applying of'plug-in' technology and a special interface of hardware, this solution exhibits some highcompatibility with different pedigree numerical control (NC) systems, such as Fanuc, Siemens,Cincinnati and so on. In order to improve CANBus for DNC application, a communicating competitionmodel of the basic CAN protocol, called CC model, is then highlighted. This model is able to satisfythe requirements that different machine tools share the communicating bandwidth fairly when theyrun concurrently. Finally the novel view of the latest advancement in CANBus-based DNC incombination with the manufacturing paradigm is also presented. 展开更多
关键词 Distributed numerical control CANBUS FIELDBUS CAM Manufacturingautomation
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A design methodology to reduce waste in the construction process 被引量:2
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作者 AndrewN.BALDWIN SimonA.AUSTIN AndrewKEYS 《Journal of Chongqing University》 CAS 2003年第U10期26-30,共5页
This paper describes a conceptual tool to enable construction professional to identify where waste is generated during the construction of buildings and address how it can be reduced. It allows an improvement in the w... This paper describes a conceptual tool to enable construction professional to identify where waste is generated during the construction of buildings and address how it can be reduced. It allows an improvement in the waste management practices on site by forecasting future waste types and volumes. It will reduce waste volumes on site through identification of wasteful design practices. The tool contributes to all stages of design and construction. At the Concept Stage of Design the proposed methodology provides a framework for reducing waste through better informed decisions. At the Detailed Design Stage it gives a methodology to address the areas of concern and provide focused information to aid the reduction of waste through informed design decisions. During construction it provides a tool to predict waste types arising on site thus allowing a system of proaclive waste management that will aid skip segregation strategies leading to improved waste recycling and waste reuse. 展开更多
关键词 建筑设计 环境保护 英国 废物利用
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Compacton, Peakon, and Foldon Structures in the (2+1)-DimensionalNizhnik-Novikov-Veselov Equation 被引量:2
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作者 ZHANGJie-Fang MENGJian-Ping +1 位作者 WUFeng-Min SIJian-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1期7-14,共8页
By the use of the extended homogenous balance method,the B(?)cklund transformation for a (2+1)- dimensional integrable model,the(2+1)-dimensional Nizhnik-Novikov-Veselov (NNV) equation,is obtained,and then the NNV equ... By the use of the extended homogenous balance method,the B(?)cklund transformation for a (2+1)- dimensional integrable model,the(2+1)-dimensional Nizhnik-Novikov-Veselov (NNV) equation,is obtained,and then the NNV equation is transformed into three equations of linear,bilinear,and tri-linear forms,respectively.From the above three equations,a rather general variable separation solution of the model is obtained.Three novel class localized structures of the model are founded by the entrance of two variable-separated arbitrary functions. 展开更多
关键词 COMPACTON PEAKON FOLDON Nizhnik-Novikov-Veselov equation
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Modelling of Equilibrium Grain Boundary Solute Segregation under Irradiation 被引量:1
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作者 ShenhuaSONG R.G.Faulkner +1 位作者 P.E.J.Flewitt LuqianWENG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第2期196-200,共5页
Both radiation-induced excess vacancies and solute-interstitials may enhance solute diffusion. The radiation-enhanced solute diffusion promotes the kinetic process of equilibrium segregation. This effect is especially... Both radiation-induced excess vacancies and solute-interstitials may enhance solute diffusion. The radiation-enhanced solute diffusion promotes the kinetic process of equilibrium segregation. This effect is especially considerable in the low temperature range. As a complement to modelling of radiation-induced non-equilibrium segregation, the radiation-created vacancy and solute-interstitial-accelerated equilibrium grain boundary solute segregation were theoretically treated. The models were applied to phosphorus segregation in α-Fe subjected to neutron irradiation. 展开更多
关键词 RADIATION Point defects DIFFUSION Grain boundary SEGREGATION
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Determination of Neutron Irradiation-Induced Phosphorus Segregation on Grain Boundaries in a P-doped 2.25Cr1Mo Steel 被引量:1
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作者 ShenhuaSONG R.G.Faulkner +3 位作者 P.E.J.Flewitt DongdongSHEN JingLIU ZexiYUAN 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第1期81-85,共5页
Irradiation-induced impurity segregation to grain boundaries is one of the important radiation effects on materials. For this reason, phosphorus segregation to prior austenite grain boundaries in a P-doped 2.25Cr1Mo s... Irradiation-induced impurity segregation to grain boundaries is one of the important radiation effects on materials. For this reason, phosphorus segregation to prior austenite grain boundaries in a P-doped 2.25Cr1Mo steel subjected to neutron irradiation is examined using field emission gun scanning transmission electron microscopy (FEGSTEM) with energy dispersive X-ray microanalysis (EDX). The steel samples are irradiated around 270 and 400℃, respectively. The irradiation dose rate and dose are -1.05×10-8 dpa/s and -0.042 dpa respectively for 270℃ irradiation, and 1.7×10-8 dpa/s and 0.13 dpa respectively for 400℃ irradiation. The FEGSTEM results indicate that there is no apparent phosphorus segregation during 270℃ irradiation but there is some during 400℃ irradiation. 展开更多
关键词 Neutron irradiation SEGREGATION Grain boundary PHOSPHORUS
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Guidance on Design of Internet-based Process Control Systems
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作者 S.H.YANG L.YANG 《自动化学报》 EI CSCD 北大核心 2005年第1期56-63,共8页
Internet-based process control is becoming new generations of control systems, in which the Internet is used as a platform for global remote monitoring and control. The obvious benefit is to enable global collaboratio... Internet-based process control is becoming new generations of control systems, in which the Internet is used as a platform for global remote monitoring and control. The obvious benefit is to enable global collaboration between operators from geographically dispersed locations, data sharing and data provision for remote monitoring and control. However, connection to an open network and the use of universal technology present new problems that did not exist with the conventional design and construction of control systems, such as time delay and data loss in Internet transmission and security. This paper reviews the latest research results and presents design guidance of Internet based monitoring and control systems. 展开更多
关键词 网络等待时间 安全性 用户界面设计 互联网 远程监控
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A Novel Class of Coherent Localized Structures for the Maccari System
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作者 ZHANGJie-Fang, MENGJian-Ping HUANGWen-Hua 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第4X期443-446,共4页
By means of the Baecklund transformation, a quite general variable separation solution of the (2+1)-dimensional Maccari systems is derived. In addition to some types of the usual localized excitations such as dromion,... By means of the Baecklund transformation, a quite general variable separation solution of the (2+1)-dimensional Maccari systems is derived. In addition to some types of the usual localized excitations such as dromion, lumps, ring soliton and oscillated dromion, breathers solution, fractal-dromion, fractal-lump and chaotic soliton structures can be easily constructed by selecting the arbitrary functions appropriately, a new novel class of coherent localized structures like peakon solution and compacton solution of this new system are found by selecting apfropriate functions. 展开更多
关键词 变量分离解 连续局限激发 二维非线性系统 峰解 峰限结构 混沌孤子结构
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GRAIN-BOUNDARY PRECIPITATION UNDER IRRADIATION IN DILUTE BINARY ALLOYS
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作者 S.H.Song Z.X.Yuan +1 位作者 J.Liu R.G.Faulkner 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2003年第5期365-374,共10页
Irradiation-induced grain boundary segregation of solute atoms frequently bring about grain boundary precipitation of a second phase because of its making the solubility limit of the solute surpassed at grain boundari... Irradiation-induced grain boundary segregation of solute atoms frequently bring about grain boundary precipitation of a second phase because of its making the solubility limit of the solute surpassed at grain boundaries. Until now the kinetic models for irradiation-induced grain boundary precipitation have been sparse. For this reason, we have theoretically treated grain boundary precipitation under irradiation in dilute binary alloys. Predictions of γ' -Ni3Si precipitation at grain boundaries are made for a dilute Ni-Si alloy subjected to irradiation. It is demonstrated that grain boundary silicon segregation under irradiation may lead to grain boundary γ'-Ni3Si precipitation over a certain temperature range. 展开更多
关键词 SEGREGATION PRECIPITATION grain boundary IRRADIATION
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New Coherent Structures in the Generalized(2+1)—Dimensional Nizhnik—Novikov—Veselov System 被引量:1
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作者 张解放 《Chinese Physics Letters》 SCIE CAS CSCD 2003年第7期1006-1008,共3页
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ROBUST SLIDING MODE DECENTRALIZED CONTROL FOR A CLASS OF NONLINEAR INTERCONNECTED LARGE-SCALE SYSTEM WITH NEURAL NETWORKS
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作者 CHENMou JIANGChang-sheng CHENWen-hua 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第4期304-310,共7页
A new decentralized robust control method is discussed for a class of nonlinear interconnected largescale system with unknown bounded disturbance and unknown nonlinear function term. A decentralized control law is pro... A new decentralized robust control method is discussed for a class of nonlinear interconnected largescale system with unknown bounded disturbance and unknown nonlinear function term. A decentralized control law is proposed which combines the approximation method of neural network with sliding mode control. The decentralized controller consists of an equivalent controller and an adaptive sliding mode controller. The sliding mode controller is a robust controller used to reduce the track error of the control system. The neural networks are used to approximate the unknown nonlinear functions, meanwhile the approximation errors of the neural networks are applied to the weight value updated law to improve performance of the system. Finally, an example demonstrates the availability of the decentralized control method. 展开更多
关键词 nonlinear large-scale systems neural networks sliding mode control decentralized control
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使用合成白炭黑提高轮胎使用寿命
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作者 M.A.Ansarifar R.Nijhawan 涂学忠 《轮胎工业》 CAS 2004年第7期411-413,共3页
关键词 合成白炭黑 沉淀法白炭黑 混炼工艺 NR胶料 硅烷 硫化速度指数 轮胎 寿命
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