期刊文献+
共找到41篇文章
< 1 2 3 >
每页显示 20 50 100
FY-2C星地面应用分系统指令与数据获取站 被引量:7
1
作者 冯小虎 夏景林 张志清 《上海航天》 北大核心 2005年第B12期111-116,共6页
介绍了风云二号(FY-2)C星地面应用分系统数据与指令接收站(CDAS)的主要技术指标、工作流程,以及与C星的星地接口与地面应用分系统其他部分的接口。说明了CDAS的天伺馈、信道、图像获取(IAS)、三点测距(TRRR)、数据收集(DCP)、遥测遥控(T... 介绍了风云二号(FY-2)C星地面应用分系统数据与指令接收站(CDAS)的主要技术指标、工作流程,以及与C星的星地接口与地面应用分系统其他部分的接口。说明了CDAS的天伺馈、信道、图像获取(IAS)、三点测距(TRRR)、数据收集(DCP)、遥测遥控(TT&C)、卫星模拟器、标校、时间统一、低速信息传输(LRIT)信息编码与发送等子系统的组成与功能。阐述了C星CDAS的设计原则,以及用群调技术实现DCP的数据解调、用扩频伪码进行TRRR定位、图像处理、TT&C增加图形化界面控制、正交相移键控(QPSK)解调器抗长连“1”功能等关键技术。在轨测试和试运行期间,C星的CDAS不仅解决暴露的问题,而且进行适应性调整。验收前测试结果表明,其功能及技术指标满足业务运行要求,设备工作正常、性能稳定。 展开更多
关键词 风云二号气象卫星 地面应用分系统 数据和指令接收站 性能 组成 关键技术
下载PDF
FY-2C星地面应用分系统工程建设 被引量:1
2
作者 庞晶 冯小虎 《上海航天》 北大核心 2005年第B12期117-120,共4页
介绍了风云二号(FY-2)C气象卫星地面应用分系统的组成、主要任务及建设目标。说明了分系统建设中采用的建立健全两总系统、成立气象卫星工程建设部和建立两总联席会议制度等行政措施。阐明了在分系统建设中采用的软件工程管理开发、加... 介绍了风云二号(FY-2)C气象卫星地面应用分系统的组成、主要任务及建设目标。说明了分系统建设中采用的建立健全两总系统、成立气象卫星工程建设部和建立两总联席会议制度等行政措施。阐明了在分系统建设中采用的软件工程管理开发、加强合同签定审批、不同设备的验收,以及严格选择基础施工单位与聘请施工监理等管理措施。建成的地面应用分系统在C星的业务运行中发挥了重要作用。 展开更多
关键词 风云二号气象卫星 地面应用分系统 组成 任务 建设 组织 管理
下载PDF
茨淮新河上桥枢纽工程信息系统集成与建模
3
作者 冯守均 徐立中 李文令 《安徽水利水电职业技术学院学报》 2003年第4期1-4,共4页
文章阐述上桥枢纽工程信息集成调度管理系统的总体设计。重点阐述了枢纽调度管理建模的整体思路,包括功能模型和应用分系统的结构划分。
关键词 递阶控制 CIMS功能结构 应用分系统 逻辑结构
下载PDF
并联DC/DC系统中高速无线通信接收装置的设计 被引量:5
4
作者 汪涛 刘升 葛芦生 《电源学报》 CSCD 北大核心 2018年第1期166-170,共5页
为了解决并联DC/DC控制系统中信息高频、单次传输量小的问题,就目前基带处理平台功能单一、灵活性差、运算效率低等问题,提出了一种改进型基带处理方案。该方案以FPGA+DSP为处理架构,依托高性能器件和高速接口搭建了基带处理平台。分别... 为了解决并联DC/DC控制系统中信息高频、单次传输量小的问题,就目前基带处理平台功能单一、灵活性差、运算效率低等问题,提出了一种改进型基带处理方案。该方案以FPGA+DSP为处理架构,依托高性能器件和高速接口搭建了基带处理平台。分别从基带处理和射频前端两个方面对无线通信系统接收装置进行硬件设计,重点研究基带处理DSP与FPGA的接口设计和零中频架构射频前端,通过FPGA对本地振荡器、A/D进行动态配置,采用基于BPSK的软件无线电平台,通过编写程序进行测试,结果验证了该方案满足科研要求,且具有一定的通用性和灵活性。 展开更多
关键词 并联DC/DC 现场可编程门阵列 零中频架构 DSP 基带处理
下载PDF
A dynamic optimization model of an integrated coal supply chain system and its application 被引量:8
5
作者 PENG Hong-jun ZHOU Mei-hua +2 位作者 LIU Man-zhi ZHANG Yu HUANG Yan-bo 《Mining Science and Technology》 EI CAS 2009年第6期842-846,共5页
Various nodes,logistics,capital flows,and information flows are required to make systematic decisions concerning the operation of an integrated coal supply system. We describe a quantitative analysis of such a system.... Various nodes,logistics,capital flows,and information flows are required to make systematic decisions concerning the operation of an integrated coal supply system. We describe a quantitative analysis of such a system. A dynamic optimization model of the supply chain is developed. It has achieved optimal system profit under conditions guaranteeing a certain level of customer satisfaction. Applying this model to coal production of the Xuzhou coal mines allows recommendations for a more systematic use of washing and processing,transportation and sale resources for commercial coal production to be made. The results show that this model,which is scientific and effective,has an important value for making reasonable decisions related to complex coal enterprises. 展开更多
关键词 coal supply chain multiple linear regression customer satisfaction dynamic optimization model
下载PDF
Application of a fuzzy analytical hierarchy process to the prediction of vibration during rock sawing 被引量:9
6
作者 Mikaeil Reza Ataei Mohammad Yousefi Reza 《Mining Science and Technology》 EI CAS 2011年第5期611-619,共9页
A new predictive model for evaluating the vibration of a sawing machine was developed using a new rock classification system. The predictors are machine parameters and a rock sawability index. The new rock classificat... A new predictive model for evaluating the vibration of a sawing machine was developed using a new rock classification system. The predictors are machine parameters and a rock sawability index. The new rock classification system includes four major parameters of the rock: uniaxial compressive strength, abrasiv- ity index, mean MoWs hardness, and Young's modulus. The FAHP approach was used when determining the weights of these parameters by six decision makers. Two groups of carbonate rocks were sawn using a fully-instrumented laboratory sawing rig at different feed rates and depths of cut. During the sawing trials system vibration was monitored as a measure of saw performance. Then, a new statistical model was obtained by multiple regression on the machining parameters and the rock sawability index. The model is very useful for the evaluation of the system vibration, and for selecting suitable machining parameters, from a limited set of mechanical properties. 展开更多
关键词 Sawability FAHP Classification Vibration
下载PDF
Asymptotical p-Moment Stability of Stochastic Impulsive Differential Equations and Its Application in Impulsive Control 被引量:1
7
作者 牛玉俊 徐伟 李红武 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第1期110-114,共5页
In this paper, the asymptotical p-moment stabifity of stochastic impulsive differential equations is studied, and a comparison theory to ensure the asymptotieal p-moment stability for trivial solution of this system i... In this paper, the asymptotical p-moment stabifity of stochastic impulsive differential equations is studied, and a comparison theory to ensure the asymptotieal p-moment stability for trivial solution of this system is established, from which we can find out whether a stochastic impulsive differential system is stable just from a deterministic comparison system. As an application of this theory, we control the chaos of stochastic Chen system using impulsive method, and a stable region is deduced too. Finally, numerical simulations verify the feasibility of our method. 展开更多
关键词 p-moment stability IMPULSIVE WHITE-NOISE stochastic differential equations
下载PDF
A novel resource co-allocation model with constraints to budget and deadline in computational grid 被引量:1
8
作者 胡志刚 肖鹏 《Journal of Central South University》 SCIE EI CAS 2009年第3期458-466,共9页
To address the issue of resource co-allocation with constraints to budget and deadline in grid environments, a novel co-allocation model based on virtual resource agent was proposed. The model optimized resources depl... To address the issue of resource co-allocation with constraints to budget and deadline in grid environments, a novel co-allocation model based on virtual resource agent was proposed. The model optimized resources deployment and price scheme through a three-side co-allocation mechanism, and applied queuing system to model the work of grid resources for providing quantitative deadline guarantees for grid applications. The validity and solutions of the model were presented theoretically. Extensive simulations were conducted to examine the effectiveness and the performance of the model by comparing with other co-allocation policies in terms of deadline violation rate, resource benefit and resource utilization. Experimental results show that compared with the three typical co-allocation policies, the proposed model can reduce the deadline violation rate to about 3.5% for the grid applications with constraints to budget and deadline. Also, the system benefits can be increased by about 30% compared with the those widely-used co-allocation policies. 展开更多
关键词 CO-ALLOCATION computational grid grid economy queuing theory DEADLINE
下载PDF
Adsorbents for Expanded Bed Adsorption: Preparation and Functionalization 被引量:3
9
作者 赵珺 姚善泾 林东强 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第4期678-687,共10页
Expanded bed adsorption(EBA),a promising and practical separation technique,has been widely studied in the past two decades.The development of adsorbents for EBA process is a challenging course,with the special design... Expanded bed adsorption(EBA),a promising and practical separation technique,has been widely studied in the past two decades.The development of adsorbents for EBA process is a challenging course,with the special design and preparation according to the target molecules and specific expanded bed systems.Many types of supporting matrices for expanded bed adsorbents have been developed,and their preparation methods are being consummated gradually.These matrices are activated and then coupled with ligands to form functionalized adsorbents,including ion-exchange adsorbents,affinity adsorbents,mixed mode adsorbents,hydrophobic charge induction chromatography adsorbents and others.In this review,the preparation of the matrices for EBA process is summa-rized,and the coupling of ligands to the matrices to prepare functionalized adsorbents is discussed as well. 展开更多
关键词 expanded bed adsorption MATRIX PREPARATION tunctionalized adsorbent CHROMATOGRAPHY SEPARATION
下载PDF
Aspect-Oriented Design Method for Embedded Systems Based on Timed Statecharts
10
作者 文欣秀 虞慧群 郑红 《China Communications》 SCIE CSCD 2013年第9期33-42,共10页
The formal modelling and verification method has become an effective way of improving the reliability and correctness of complex,safety-critical embedded systems.Statecharts are widely used to formally model embedded ... The formal modelling and verification method has become an effective way of improving the reliability and correctness of complex,safety-critical embedded systems.Statecharts are widely used to formally model embedded applications,but they do not realise the reasonable separation of system concerns,which would result in code scattering and tangling.Aspect-Oriented Software Development(AOSD)technology could separate crosscutting concerns from core concerns and identify potential problems in the early phase of the software development life cycle.Therefore,the paper proposes aspect-oriented timed statecharts(extended timed statecharts with AOSD)to separately model base functional requirements and other requirements(e.g.,scheduling,error handling),thereby improving the modularity and development efficiency of embedded systems.Furthermore,the dynamic behaviours of embedded systems are simulated and analysed to determine whether the model satisfies certain properties(e.g.,liveness,safety)described by computation tree logic formulae.Finally,a given case demonstrates some desired properties processed with respect to the aspect-oriented timed statecharts model. 展开更多
关键词 embedded systems model check-ing timed statecharts computation tree logic
下载PDF
Some problems of GPS RTK technique application to mining subsidence monitoring 被引量:14
11
作者 Liu Chao Zhou Feng +1 位作者 Gao Jingxiang Wang Jian 《International Journal of Mining Science and Technology》 2012年第2期223-228,共6页
Owing to the variability of mine surfaces, it is difficult to obtain the deformation monitoring data of the observation stations by traditional leveling technique. GPS RTK (Real-Time Kinematic) technique was employe... Owing to the variability of mine surfaces, it is difficult to obtain the deformation monitoring data of the observation stations by traditional leveling technique. GPS RTK (Real-Time Kinematic) technique was employed to the subsidence observation in this paper, and its main sources of errors including rover pole deflection of the vertical, un-modeled systematic errors (gross error, multipath delay etc.) and the height transformation error, were analyzed systematically. Based on the fundamental theories of spherical fit- ting and Empirical Mode Decomposition (EMD), the error reduction models were studied exhaustively. And two experiments were done in different environment to test the proposed models. The results show that the proposed methods can achieve a fourth-grade leveling accuracy, with (Root-Mean-Square) RMS in three orthogonal directions (N, E and H) of 4.1, 3.3 and 3.1 ram, respectively, by 3-5 rain continuous shaking of the observation GPS antenna, fully satisfying for mine surface subsidence deformation monitoring. 展开更多
关键词 GPS RTKSurface subsidenceKinematic positioningMultipath delay
下载PDF
Dendritic Cells Algorithm and Its Application to Nmap Portscan Detection 被引量:1
12
作者 Fang Xianjin Song Danjie 《China Communications》 SCIE CSCD 2012年第3期145-152,共8页
Dendritic Cells Algorithm (DCA) is a new development in Artificial Immune System (AIS). It has various parameters, and as yet has not been ex- tensively tested. The general applicability of the al- gorithm to a va... Dendritic Cells Algorithm (DCA) is a new development in Artificial Immune System (AIS). It has various parameters, and as yet has not been ex- tensively tested. The general applicability of the al- gorithm to a variety of problems is d. The aim of this work is to demonstrate the feas^ility and ro- bustness of the algorithm, and the sensitivity to the change of various parameters in a series of experi- ments for Nmap portscan detection by using DCA. Experiment results show that the algorithm per- forms well on the task of detecting a ping based Nmap portscan. Sensitivity analysis is also per- formed. True positive rate is higher for the detec- tion of anomaly processes and false positive rate is lower for the detection of normal orocesses. 展开更多
关键词 AIS DCA portscan anomaly detection
下载PDF
Application of PID Controller Based on BP Neural Network in Export Steam’s Temperature Control System 被引量:4
13
作者 朱增辉 孙慧影 《Journal of Measurement Science and Instrumentation》 CAS 2011年第1期84-87,共4页
By combining the Back-Propagation (BP) neural network with conventional proportional Integral Derivative (PID) controller, a new temperature control strategy of the export steam in supercritical electric power pla... By combining the Back-Propagation (BP) neural network with conventional proportional Integral Derivative (PID) controller, a new temperature control strategy of the export steam in supercritical electric power plant is put forward. This scheme can effectively overcome the large time delay, inertia of the export steam and the influencee of object in varying operational parameters. Thus excellent control quality is obtaitud. The present paper describes the development and application of neural network based controller to control the temperature of the boiler's export steam. Through simulation in various situations, it validates that the control quality of this control system is apparently superior to the conventional PID control system. 展开更多
关键词 PID controller based on BP neural network supercritical power unit export steam temperature large timedelay
下载PDF
Functional Role of Neuropeptide Leucokininll in Growth Inhibition of Red Palm Weevil Rhynchophorus ferrugineus 被引量:1
14
作者 Mona Mohammed Saleh A1-Dawsary 《Journal of Agricultural Science and Technology(A)》 2012年第8期988-996,共9页
Peptides are known to on act to discourage the growth of insects. In this perspective, authors studied the biological and physiological effects of LeucokininlI on the growth of Red Palm Weevil through adult insect fee... Peptides are known to on act to discourage the growth of insects. In this perspective, authors studied the biological and physiological effects of LeucokininlI on the growth of Red Palm Weevil through adult insect feeding of the sugar cane treated with different concentrations (0.05%, 0. I%, 0.25%, 0.4%) and biological effects on the number of eggs, the percentage of hatching, the length of the generation and the proportion of deformation, Results showed that there is a significant reduction in the number of eggs laid by the insects as the average number of eggs/female 75.7, 63.5, 59.4, 55.1 egg for each of the concentrations, respectively, compared with the average 140.2 egg in the control group, and reduction of percentages of hatching in all treatment as 71.4%, 64.6%, 70% and 71.5% respectively, compared with 79.3% of the control group. The percentage of deformations in egg densities included 44.4%, 15.4%, 22.6%, 27.8% compared to the control group. The results showed that there are a number of large deformations in the resulting larvae for different treatments. The conclusion is drawn that this study using LeucokininlI confirmed inhibition growth and caused an imbalance in the development stages of different insects due to its effect on the hormones that control molting of insects. This conclusion is furthermore apparent in the larval stage, as it appeared that Leucokininll prevents the insect from completing its life cycle. Test results using LeucokininlI are encouraging, and its future potential use in reducing Red Palm Weevil deserves broader studies. If the spread of currently known that this LeucokininlI is without prejudice to the work of the hormonal system. 展开更多
关键词 R. ferrugineus NEUROPEPTIDE HATCHING DEFORMATION treatment HORMONES LeucokininlI.
下载PDF
The Intelligent Teaching Resource Program: Applications to Writing
15
作者 WANG Ji-jun 《Sino-US English Teaching》 2013年第3期228-233,共6页
This paper examined the computer-assisted TRP (Teaching Resource Program), which is an intelligent writing program. Different from previous research, this study emphasized TRP's integrative and holistic functions o... This paper examined the computer-assisted TRP (Teaching Resource Program), which is an intelligent writing program. Different from previous research, this study emphasized TRP's integrative and holistic functions of intelligent analysis, intelligent scoring, and intelligent comment on writing pieces. In what follows, this paper conducted a study of intelligent essay scoring system related to intelligent analysis, intelligent scoring, and intelligent comment of the writing pieces. Also, this paper provided a literature review of existing computer-assisted essay scoring systems and analyzed the advantages and disadvantages of them. Based on these findings in our research, we can conclude that the integrative and holistic computer-assisted TRP can effectively analyze, score, and comment essays, consequently enhancing the writing performance. Some useful implications from this study include that the computer-assisted TRP should be further integrated with writing learning and instruction 展开更多
关键词 TRP (Teaching Resource Program) intelligent analysis intelligent scoring intelligent comment
下载PDF
The applied value of modified POSSUM score in evaluating lung cancer surgery’s risk
16
作者 Dongmin Lu Kaibo Han +3 位作者 Yuan Zhou Gang Xu Hong Liu Dong Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2013年第7期315-318,共4页
Objective: The aim of this study was to explore the modified physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM) scoring system and the relationship between predicted dat... Objective: The aim of this study was to explore the modified physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM) scoring system and the relationship between predicted data and actual data of complication and surgical mortality of lung cancer radical surgery made by such score system. Methods: Retrospective analysis on the 86 cases of the clinical materials of patients with primary lung cancer radical surgery for thoracic surgery of line lung cancer in the 81st Hospital of PLA from October 2010 to October 2011 and using the POSSUM scoring system to predict the cases of postoperative complication and death toll, then making a comparison with the actual cases. Results: The POSSUM scoring system predicting 29 cases of postoperative complications, but 32 cases of practical complications, the difference between them has no statistical significance (P﹥0.05), 8 cases of predicted postoperative deaths, 2 cases of practical deaths, by comparison, there was statistical significance (P﹤0.05). Conclusion: The modified POSSUM scoring system can be used to predict the postoperative complication of lung surgery patients, but sometimes overestimates the postoperative death cases. 展开更多
关键词 the modified physiological and operative severity score for the enumeration of mortality and morbidity (POS-SUM) score lung cancer radical surgery complications FATALITY
下载PDF
Application of Bifurcation Analysis on Active Distribution Systems
17
作者 Mohamed Mahmoud Aly Ahmed Bedawy Mamdouh Abdel-Akher 《Journal of Energy and Power Engineering》 2012年第12期1994-2000,共7页
This paper presents the application of bifurcation method on the steady state three-phase load-flow Jacobian method to study the voltage stability of unbalanced distribution systems. The eigenvalue analysis is used to... This paper presents the application of bifurcation method on the steady state three-phase load-flow Jacobian method to study the voltage stability of unbalanced distribution systems. The eigenvalue analysis is used to study distribution system behavior under different operating conditions. Two-bus connected by asymmetrical line is used as the study system. The effects of both unbalance and extreme loading conditions are investigated. Also, the impact of distributed energy resources is studied. Different case studies and loading scenarios are presented to trace the eigenvalues of the Jacobian matrix. The results exhibit the existence of a new bifurcation point which may not be related to the voltage stability. 展开更多
关键词 BIFURCATION voltage stability EIGENVALUES saddle node bifurcation DERs (distributed energy resources).
下载PDF
Eight-Regularity of Types of Crop Capacity Structure of Winter Wheat
18
作者 N. N. Petrova 《Journal of Agricultural Science and Technology(B)》 2011年第2期285-296,共12页
The elements of crop capacity structure of 13 summer characteristics in 33 winter wheat varieties, qualitative three-regularity and quantitative eight-regularity are investigated through the application of systematic ... The elements of crop capacity structure of 13 summer characteristics in 33 winter wheat varieties, qualitative three-regularity and quantitative eight-regularity are investigated through the application of systematic approach. The principle of triadness applied in a language, in a genetic code and other codes is used, i.e. the logic homology is employed. The purpose are (1) to show the use of a systematic approach to the analysis of elements of crop capacity structure of winter wheat; (2) to analyze efficiency, the years of harvests and winter hardiness; (3) to find the way of selection and varieties assessment in terms of the elements efficiency. The quantitative compatibility as the highest with the sign "+" and the lowest with the sign "-" in terms of elements efficiency gives eight types of crop capacities. The type of crop capacity structure "+++" can serve as a full (higher) measure of a variety adaptableness and optimality of technologies. The triad of three characteristics as a type-"+++" in which the first sign is the quantity of ears (QE); the second is a quantity of grains (QG); the third is the weight of grains (WG) creates the highest level of crop capacity. 展开更多
关键词 Category of triadness eight-regularity crop capacity efficiency quantity of ears in 1 m^2 (QE) quantity of grains in anear (QG) weight of 1 000 grains (WG) winter wheat.
下载PDF
Printed elliptical slot UWB antenna for dual-banded application
19
作者 蔡云龙 冯正和 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第5期737-740,共4页
Based on the analysis of printed elliptical slot (PES) UWB antenna,a dual-banded PES antenna is designed for WLAN and UWB bands at 2.4 GHz.The design cooperates two important wireless commutation system antennas into ... Based on the analysis of printed elliptical slot (PES) UWB antenna,a dual-banded PES antenna is designed for WLAN and UWB bands at 2.4 GHz.The design cooperates two important wireless commutation system antennas into one printed antenna.In the design,a circular slot structure is presented,which is suitable for the band ejection.Characteristics of the designed antenna are analyzed and key parameters,such as S11,S21 and VSWR are measured.E-field distribution of the surface is simulated and analyzed. 展开更多
关键词 UWB dual-banded antenna printed elliptical slot (PES) antenna circular slot
下载PDF
Application of Laboratory Information Management System in Tea Pesticide Analysis Laboratory
20
作者 Chia-Chang Wu Hsiao-Ying Yang +3 位作者 Ya-Hui Chuang Yu-Ju Huang Li-Chen Lin Iou-ZenChen 《Journal of Environmental Science and Engineering(B)》 2012年第12期1311-1321,共11页
The aim of this paper is to establish LIMS (laboratory information management system) for the tea pesticides analysis accredited laboratories in Taiwan. The LIMS could help Tungting station and Nantou pesticide insp... The aim of this paper is to establish LIMS (laboratory information management system) for the tea pesticides analysis accredited laboratories in Taiwan. The LIMS could help Tungting station and Nantou pesticide inspection station to computerize the pesticide analysis data. It has completed eight management subsystems so far, including the basic information management subsystem, thesample processing management subsystem, the analysis data management subsystem, the analysis report management subsystem, the inspection standard management subsystem, the instrument connection management subsystem, the laboratory personnel training management subsystem and the laboratory quality document management subsystem. Using the automatic tea pesticide analysis information management system could help laboratory operations to reduce the amount of excess paperwork and human resource, which could ensure the analysis data quality is traceable and reliable. 展开更多
关键词 LIMS TEA pesticide analysis traceable.
下载PDF
上一页 1 2 3 下一页 到第
使用帮助 返回顶部