期刊文献+
共找到67篇文章
< 1 2 4 >
每页显示 20 50 100
便携式场强测试控发台的实现方案
1
作者 徐敦礼 王强 马健康 《铁道通信信号》 北大核心 2004年第7期32-34,共3页
介绍了便携式无线列调场强测试控发台的构成和实现方案 ,并简述了场强测试的设置。
关键词 便携式无线列调场强测试控发台 构成 工作原理 铁路 设置
下载PDF
导弹火控训练模拟器发控台的设计 被引量:1
2
作者 宋艳波 王光辉 +1 位作者 高青伟 任永吉 《计算机测量与控制》 CSCD 北大核心 2012年第11期3002-3004,共3页
针对导弹火控系统训练特点,采用"虚实结合"的模式设计了导弹火控系统训练模拟器总体架构,分析了导弹发控台软硬件结构,研究了系统网络通信和1553B通信等关键技术,解决了训练模拟器的通信问题;该系统在应用中运行稳定、仿真度... 针对导弹火控系统训练特点,采用"虚实结合"的模式设计了导弹火控系统训练模拟器总体架构,分析了导弹发控台软硬件结构,研究了系统网络通信和1553B通信等关键技术,解决了训练模拟器的通信问题;该系统在应用中运行稳定、仿真度高、响应速度快,提高了装备训练的效率,具有很高的实用性。 展开更多
关键词 导弹 火控系统 模拟训练器
下载PDF
基于Silverlight、DeepEarth和WCF的台风信息发布系统
3
作者 刘开兵 《福建电脑》 2011年第1期89-90,92,共3页
目前的台风预报系统和有关台风信息发布的系统中,台风信息发布的动态性、丰富性和及时性要求未能同时得到满足。本文结合互联网发展的新技术,研究并实现了一种兼具科学性和形象化的台风信息发布方法。该方法可以显著提高台风信息发布的... 目前的台风预报系统和有关台风信息发布的系统中,台风信息发布的动态性、丰富性和及时性要求未能同时得到满足。本文结合互联网发展的新技术,研究并实现了一种兼具科学性和形象化的台风信息发布方法。该方法可以显著提高台风信息发布的可视化效果,可为台风灾害预警系统的建设提供技术支持。 展开更多
关键词 信息 SILVERLIGHT DeepEarth Windows COMMUNICATION FOUNDATION
下载PDF
日本短波标准电波发播台JJY的测沿革
4
作者 王蒲凤 《天文文献情报》 1990年第4期48-48,共1页
关键词 短波 电波
下载PDF
A Novel Verification Development Platform for Passive UHF RFID Tag 被引量:1
5
作者 陈力颖 侯春萍 +3 位作者 毛陆虹 吴顺华 徐振梅 王振兴 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第11期1696-1700,共5页
This paper introduces a novel verification development platform for the passive UHF RFID tag,which is compatible with the ISO/IEC 18000-6B standard,operating in the 915MHz ISM band. This platform efficiently reduces t... This paper introduces a novel verification development platform for the passive UHF RFID tag,which is compatible with the ISO/IEC 18000-6B standard,operating in the 915MHz ISM band. This platform efficiently reduces the design and development time and cost, and implements a fast prototype design of the passive UHF RFID tag. It includes the RFID analog front end and the tag control logic, which is implemented in an Altera ACEX FPGA. The RFID analog front end, which is fabricated using a Chartered 0.35μm two-poly four-metal CMOS process, contains a local oscillator, power on reset circuit, matching network and backscatter, rectifier, regu- lator,AM demodulator, etc. The platform achieves rapid, flexible and efficient verification and development, and can also be fit for other RFID standards after changing the tag control logic in FPGA. 展开更多
关键词 verification development platform passive UHF RFID TAG FPGA
下载PDF
Early Warning System of Important Meteorological Disasters in Hunan Province
6
作者 朱国强 周慧 +1 位作者 刘瑞琪 敦海峰 《Agricultural Science & Technology》 CAS 2013年第4期672-675,688,共5页
Based on technologies of GRADS, Delphi, WEB and an SQLServer, distri- bution system for major meteorological disasters early warning information in Hunan Province was established. The system consists of warning tips, ... Based on technologies of GRADS, Delphi, WEB and an SQLServer, distri- bution system for major meteorological disasters early warning information in Hunan Province was established. The system consists of warning tips, early warning for different media and early warning query statistics and the network terminal of the system platform includes a business database server, a message platform database server, a sending server and a receiving terminal. The system enjoys some func- tions, such as examination by different users, on-time updating and effectiveness of flood prevention, construction of excessive warning channel, construction of compre-hensive warning information platform and further improvement of information distribution. The system provides references for prevention and reduction of important me- teorological disasters in Hunan. 展开更多
关键词 Meteorological disasters Warning information Distribution platform
下载PDF
BPM时号异常现象的实验研究
7
作者 陈洪卿 《电波科学学报》 EI CSCD 1989年第2期193-197,共5页
一、实验测量为了进一步研究 BPM 时号异常现象,在距 BPM 发射台1000公里以内的六个台站,利用高精度的原子钟守时系统和长波定时技术测定了 BPM 时号到各接收点的传递时延并进行统计分析。每小时收测各个载频上的 BPM 时号,24小时连续收... 一、实验测量为了进一步研究 BPM 时号异常现象,在距 BPM 发射台1000公里以内的六个台站,利用高精度的原子钟守时系统和长波定时技术测定了 BPM 时号到各接收点的传递时延并进行统计分析。每小时收测各个载频上的 BPM 时号,24小时连续收测,每个季节收测10天。 展开更多
关键词 BPM时号 电波传播 短波 发台
下载PDF
Effects of Seedling Cultivation Methods on Seedling Cultivation of Major Vegetables
8
作者 徐海 宋波 +2 位作者 陈龙正 卢之道 袁希汉 《Agricultural Science & Technology》 CAS 2015年第4期671-674,共4页
Objective] The alm was to expIore the effects of cuItivation methods on vegetabIe growth in seedIing stage. [Method] The test incIuded 4 treatments, as foI-Iows: treatment 1 (T1) where seedIings were cuItivated as ... Objective] The alm was to expIore the effects of cuItivation methods on vegetabIe growth in seedIing stage. [Method] The test incIuded 4 treatments, as foI-Iows: treatment 1 (T1) where seedIings were cuItivated as per water fiIm-based cuI-tivation and irrigation proceeded reguIarIy; treatment 2 (T2) where irrigation proceed-ed continuousIy as per water fiIm-based cuItivation; treatment 3 (T3) where seedIings were cuItivated as per fIoating nursing; controI treatment (CK) where seedIings were cuItivated as per seedIing-tray cuItivation in order to survey the number of germinated seedIings per tray. [Result] Both of water fiIm-based cuItiva-tion and fIoating nursing took advantages in germination speed and aduIt seedIing rate, compared with tray cuItivation method. [Conclusion] Water fiIm-based cuItivation and fIoating nursing make innovations in water management during seedIing cuItiva-tion, which improve germination speed, aduIt seedIing rate and seedIing quality, making contribution to Iarge-scale production of greenhouse vegetabIes through ap-pIications and practices. 展开更多
关键词 VEGETABLE Seedling cuItivatlon The rate of seedling germinatlon Quality of seedlings
下载PDF
DESIGN OF NEW TEST FACILITY FOR MICRO-TURBO-MACHINERY
9
作者 夏晨 黄国平 陈杰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第4期288-298,共11页
Micro-turbine engine has no enough space for measuring impeller characteristics,so the design and the construction of a new test facility of micro-turbo-machinery are presented for micro-centrifugal compressors and ra... Micro-turbine engine has no enough space for measuring impeller characteristics,so the design and the construction of a new test facility of micro-turbo-machinery are presented for micro-centrifugal compressors and radial turbines.The facility is used for the full speed compressor test and the long duration hot turbine test.To rapidly adjust the testing condition,all regulations of the operating state are automatically completed by the control system.The facility is also used for testing the impeller performance with a series of diameter from 55 mm to 180 mm as a result of the modular design.A thermal protection system is designed to avoid the heat distortion caused by the high turbine inlet temperature over 1 100 K and provide a proper experimental environment for the electronic components.A photoelectric torque transducer with the accuracy of 1% is designed to measure the torque of rigid shaft at a high speed of 125 000 r/min.The designing techniques for micro-turbo-machineries are verified by the impeller testing of the facility. 展开更多
关键词 engines turbo-machinery test facility PERFORMANCE
下载PDF
Study on Growth and Development Rules and Growth Curve Fitting of Minghua Black Minks
10
作者 荣敏 涂剑锋 +3 位作者 张志明 王淑茗 高峰 邢秀梅 《Agricultural Science & Technology》 CAS 2017年第2期285-286,302,共3页
Growth curves of Minghua black minks at 0-180 days old were fitted and analyzed by using two growth models Logistic and Gompertz. The results showed that the growth curves of Minghua black minks could be fitted very w... Growth curves of Minghua black minks at 0-180 days old were fitted and analyzed by using two growth models Logistic and Gompertz. The results showed that the growth curves of Minghua black minks could be fitted very well by Logistic model and Gompertz model (the degree of fitting FF≥0.99), but Gompertz model was better at fitting and predicting their weight. 展开更多
关键词 Minghua black minks Growth curve Non-lineared models Development rules FITTING
下载PDF
Exploration and Analysis on Grape-based Wine Culture Promotion and Development 被引量:5
11
作者 李娟 姜新 于立芝 《Agricultural Science & Technology》 CAS 2015年第4期765-768,共4页
Yantal has the most compIete cuIture of grape-based wines in China. The research expIored connotation and promotion degrees of cuIture of grape wines, an-alyzed recognition of consumers on cuIture of grape wine in Yan... Yantal has the most compIete cuIture of grape-based wines in China. The research expIored connotation and promotion degrees of cuIture of grape wines, an-alyzed recognition of consumers on cuIture of grape wine in Yantal, promotion and deveIopment potential of grape wine cuIture, and proposed countermeasures and suggestions in order to advance cuIture industry of grape wines in Yantal. 展开更多
关键词 Yantal Grape-based wine cuIture Development potentlal
下载PDF
Framework Design of Emergency Public Warning Information Release Platform in Hunan Province 被引量:2
12
作者 李伦 朱国强 陈英 《Agricultural Science & Technology》 CAS 2013年第8期1150-1153,共4页
Construction background of Hunan emergency public warning information release platform was introduced,and current status and demands of provincial information release were analyzed.Supported by GIS,Java,and Net,Hunan ... Construction background of Hunan emergency public warning information release platform was introduced,and current status and demands of provincial information release were analyzed.Supported by GIS,Java,and Net,Hunan early warning information release platform of public emergency was constructed based on ORACLE database and Windows 2008 Server,achieving information collection,packaging,transmission,de-packaging,and releasing concentration,standard and processing.In addition,the framework and functional characters of the system were illustrated and the innovation points were explored.The system provides guarantee for meteorological services and disaster prevention or reducing of Hunan public emergencies. 展开更多
关键词 Public emergency Release platform Early-warning information
下载PDF
Developing a Risk Assessment Model for Typhoon-triggered Debris Flows 被引量:2
13
作者 Jieh-Jiuh WANG Hoe I.LING 《Journal of Mountain Science》 SCIE CSCD 2011年第1期10-23,共14页
A methodology is developed for interactive risk assessment of physical infrastructure and spatially distributed response systems subjected to debris flows.The proposed framework is composed of three components,namely ... A methodology is developed for interactive risk assessment of physical infrastructure and spatially distributed response systems subjected to debris flows.The proposed framework is composed of three components,namely geotechnical engineering,geographical information systems and disaster management.With the integration of slope stability analysis,hazard scenario and susceptibility,geological conditions are considered as temporary static data,while meteorological conditions are treated as dynamic data with a focus on typhoons.In this research,the relevant parameters required for database building are defined,and the procedures for building the geological database and meteorological data sets are explained.Based on the concepts and data sets,Nantou and Hualien in Taiwan are used as the areas for case studies. 展开更多
关键词 Debris flow disaster HAZARD RISK VULNERABILITY Slope stability
下载PDF
High-Speed EMU TCMS Design and LCC Technology Research 被引量:2
14
作者 Hongwei Zhao Zhiping Huang Ying Mei 《Engineering》 SCIE EI 2017年第1期122-129,共8页
This paper introduces the high-speed electrical multiple unit (EMO) life cycle, including the design, manufacturing, testing, and maintenance stages. It also presents the train control and monitoring system (TCMS)... This paper introduces the high-speed electrical multiple unit (EMO) life cycle, including the design, manufacturing, testing, and maintenance stages. It also presents the train control and monitoring system (TCMS) software development platform, the TCMS testing and verification bench, the EMU driving simulation platform, and the EMU remote data transmittal and maintenance platform. All these platforms and benches combined together make up the EMU life cycle cost (LCC) system. Each platform facilitates EMU LCC management and is an important part of the system. 展开更多
关键词 Electrical multiple unit Train control and monitoring system Train communication network Life cycle cost Development platform Testing bench Simulation Remote data transmittal
下载PDF
DPOI: Distributed Software System Development Platform for Ocean Information Service
15
作者 GUO Zhongwen HU Keyong +1 位作者 JIANG Yongguo SUN Zhaosui 《Journal of Ocean University of China》 SCIE CAS 2015年第1期65-74,共10页
Ocean information management is of great importance as it has been employed in many areas of ocean science and technology. However, the developments of Ocean Information Systems(OISs) often suffer from low efficiency ... Ocean information management is of great importance as it has been employed in many areas of ocean science and technology. However, the developments of Ocean Information Systems(OISs) often suffer from low efficiency because of repetitive work and continuous modifications caused by dynamic requirements. In this paper, the basic requirements of OISs are analyzed first, and then a novel platform DPOI is proposed to improve development efficiency and enhance software quality of OISs by providing off-the-shelf resources. In the platform, the OIS is decomposed hierarchically into a set of modules, which can be reused in different system developments. These modules include the acquisition middleware and data loader that collect data from instruments and files respectively, the database that stores data consistently, the components that support fast application generation, the web services that make the data from distributed sources syntactical by use of predefined schemas and the configuration toolkit that enables software customization. With the assistance of the development platform, the software development needs no programming and the development procedure is thus accelerated greatly. We have applied the development platform in practical developments and evaluated its efficiency in several development practices and different development approaches. The results show that DPOI significantly improves development efficiency and software quality. 展开更多
关键词 ocean information system development platform software customization COMPONENTS
下载PDF
Predict typhoon-induced storm surge deviation in a principal component back-propagation neural network model 被引量:1
16
作者 过仲阳 戴晓燕 +1 位作者 栗小东 叶属峰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期219-226,共8页
To reduce typhoon-caused damages, numerical and empirical methods are often used to forecast typhoon storm surge. However, typhoon surge is a complex nonlinear process that is difficult to forecast accurately. We appl... To reduce typhoon-caused damages, numerical and empirical methods are often used to forecast typhoon storm surge. However, typhoon surge is a complex nonlinear process that is difficult to forecast accurately. We applied a principal component back-propagation neural network (PCBPNN) to predict the deviation in typhoon storm surge, in which data of the typhoon, upstream flood, and historical case studies were involved. With principal component analysis, 15 input factors were reduced to five principal components, and the application of the model was improved. Observation data from Huangpu Park in Shanghai, China were used to test the feasibility of the model. The results indicate that the model is capable of predicting a 12-hour warning before a typhoon surge. 展开更多
关键词 TYPHOON storm surges forecasts principal component back-propagation neural networks(PCBPNN) Changjiang (Yangtze) River estuary
下载PDF
Association between MDM2-SNP309 and hepatocellular carcinoma in Taiwan Residents population 被引量:6
17
作者 Jyh-Der Leu I-Feng kin +3 位作者 Ying-Fang Sun Su-Mei Chen Chih-Chao Liu Yi-Jang Lee 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第44期5592-5597,共6页
AIM:To investigate the risk association and compare the onset age of hepatocellular carcinoma(HCC) patients in Taiwan with different genotypes of MDM2- SNP309. METHODS:We analyzed MDM2-SNP309 genotypes from 58 patient... AIM:To investigate the risk association and compare the onset age of hepatocellular carcinoma(HCC) patients in Taiwan with different genotypes of MDM2- SNP309. METHODS:We analyzed MDM2-SNP309 genotypes from 58 patients with HCC and 138 cancer-free healthy controls consecutively.Genotyping of MDM2-SNP309 was conducted by restriction fragment length polymor- phism assay. RESULTS:The proportion of homozygous MDM2- SNP309 genotype(G/G)in cases and cancer-free healthy controls was similar(17.2%vs 16.7%).Multi-variate analysis showed that the risk of G/G genotypeof MDM2-SNP309 vs wild-type T/T genotype in patients with HCC was not significant(OR=1.265,95% CI=0.074-21.77)after adjustment for sex,hepatitis B or C virus infection,age,and cardiovascular disease/ diabetes.Nevertheless,there was a trend that GG genotype of MDM2-SNP309 might increase the risk in HCC patients infected with hepatitis virus(OR=2.568, 95%CI=0.054-121.69).Besides,the homozygous MDM2-SNP309 genotype did not exhibit a significantly earlier age of onset for HCC. CONCLUSION:Current data suggest that the asso- ciation between MDM2-SNP309 GG genotype and HCC is not significant,while the risk may be enhanced in patients infected by hepatitis virus in Taiwan. 展开更多
关键词 MDM2 protein Hepatocellular carcinoma TAIWAN Tumor suppressor protein p53
下载PDF
RELATION BETWEEN SUMMER TYPHOON FREQUENCY ANOMALIES IN WEST PACIFIC AND ENSO EVENTS AND THE ANOMALOUS ATMOSPHERIC CIRCULATION CHARACTERISTICS
18
作者 周学鸣 魏应植 吴陈锋 《Journal of Tropical Meteorology》 SCIE 2006年第1期16-23,共8页
By using data of serially numbered typhoons in northwestem Pacific and NOAA OLR data and NCEP/NCAR reanalysis data of wind field, based on the statistics and study of the relationship between the calendar years with m... By using data of serially numbered typhoons in northwestem Pacific and NOAA OLR data and NCEP/NCAR reanalysis data of wind field, based on the statistics and study of the relationship between the calendar years with more (or fewer) summer typhoons and ENSO events, we compared the composites of OLR eigenvectors and tropical summer wind fields during E1 Nino and La Nino events with more or fewer than normal summer typhoons, respectively. The results show that, in summer, without remarkable systematic anomalies of Mascarene High and Australia High in South Hemisphere, the anomaly of Walker circulation will dominate and follow the rule of ENSO impacts to atmospheric circulation and typhoon frequency. Otherwise, when systematic anomalies of Australia High appear during the El Nino events, circulation anomalies in the South Hemisphere will dominate, and many more typhoons will occur. In 1999, which is a special year of La Nina events, northward and eastward monsoon was induced by the stronger Mascarene High, and fewer typhoons arose. The typhoon source are regions where weak vertical wind shear, warm pool in westem Pacific and the area with monsoon troughs are overlapping with each other. Finally, this paper analyzes and compares the source locations and ranges of more (fewer) typhoons in the events of El Nino and La Nino, respectively. 展开更多
关键词 typhoon frequency ENSO events atmospheric circulation anomalies
下载PDF
Model Refinement for Offshore Platforms: Experimental Study
19
作者 ZHANG Min CHEN Zongli WU Yanjian 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第4期617-626,共10页
Offshore jacket platforms are widely used in offshore oil and gas exploitation.Finite element models of such structures need to have many degrees of freedom(DOFs) to represent the geometrical detail of complex structu... Offshore jacket platforms are widely used in offshore oil and gas exploitation.Finite element models of such structures need to have many degrees of freedom(DOFs) to represent the geometrical detail of complex structures,thereby leading to incompatibility in the number of DOFs of experimental models.To bring them both to the same order while ensuring that the essential eigen-properties of the refined model match those of experimental models,an extended model refinement procedure is presented in this paper.Vibration testing of an offshore jacket platform model is performed to validate the applicability of the proposed approach.A full-order finite element model of the platform is established and then tuned to meet the measured modal properties identified from the acceleration signals.Both model reduction and modal expansion methods are investigated,as well as various scenarios of sensor arrangements.Upon completion of the refinement,the updated jacket platform model matches the natural frequencies of the measured model well. 展开更多
关键词 jacket platform model refinement model updating model reduction modal expansion finite element method
下载PDF
Call Warrants Impact on Underlying Stocks: The Taiwan Experience
20
作者 LIU Shu-Ing LEE Ching-Yi 《Chinese Business Review》 2011年第2期77-83,共7页
On the basis of the price, volume and volatility of underlying stocks, this article empirically investigates the impact of 273 Taiwan call warrants on underlying stocks. Discussions by the market risk, depth, tightnes... On the basis of the price, volume and volatility of underlying stocks, this article empirically investigates the impact of 273 Taiwan call warrants on underlying stocks. Discussions by the market risk, depth, tightness and liquidity, changes on underlying stocks due to warrants issuance, are investigated. In this study, the CAPM is applied for evaluating the market risk, the Kyle model for the market depth, the averaged best five bid-ask spread for the market tightness and the averaged turnover rate for the market liquidity. The empirical results indicate that the most significant influence is the market liquidity, the market tightness next; the market risk and market depth are non-significant. 展开更多
关键词 CAPM market depth market liquidity market tightness WARRANTS
下载PDF
上一页 1 2 4 下一页 到第
使用帮助 返回顶部