期刊文献+
共找到12篇文章
< 1 >
每页显示 20 50 100
On Group Phase Quantization and Its Physical Characteristics 被引量:4
1
作者 DU Bao-Qiang ZHOU Wei +1 位作者 YU Jian-Guo DONG Shao-Feng 《Chinese Physics Letters》 SCIE CAS CSCD 2011年第5期64-67,共4页
The physical characteristics of phase quantum are further revealed,based on the proposition of concepts of the greatest common factor frequency,the least common multiple period,quantized phase shift resolution and equ... The physical characteristics of phase quantum are further revealed,based on the proposition of concepts of the greatest common factor frequency,the least common multiple period,quantized phase shift resolution and equivalent phase comparison frequency.Then the problem of phase comparison between different frequency signals is certified in detail.Using the basic principle of phase comparison between different frequencies and the variation law of group phase difference,a point of view on group phase quantization is presented.Group phase quantum is not only an indivisible individual of group phase,but also a basic unit composing group phase difference.It is equal to the equivalent phase comparison period of phase comparison between different frequencies in size.Experimental results show not only a high measurement resolution of 10^(-12)/s in frequency measurement based on group phase quantum,but also a super-high locked phase precision of 10^(-13)/s in active H atomic clock. 展开更多
关键词 PHASE QUANTUM COMPARISON
下载PDF
Study on WSN Localization Algorithm and Simulation Model for Intelligent Transportation System
2
作者 Lian-zhou GAO 《International Journal of Technology Management》 2013年第2期23-27,共5页
This paper conducts research on the algorithm to improve the location of Wireless Sensor Network (WSN) in Intelligent Transportation System (ITS). The localization algorithm introduced an improved RSSI vehicle loc... This paper conducts research on the algorithm to improve the location of Wireless Sensor Network (WSN) in Intelligent Transportation System (ITS). The localization algorithm introduced an improved RSSI vehicle localization algorithm based on multi-path effect and Gaussian white noise. The localization results under different values of Gaussian white noise and different density of beacon nodes are analyzes, and Kalman filtering algorithm is introduced to reduce the influence of signal noise. Finally, a simulation model of ITS is developed to test the algorithm based on mixed noise and Kalman filtering algorithm, which is used to simulate the localization of real vehicles. The simulation shows the algorithm has effect to improve location accuracy and to application 展开更多
关键词 Intelligent Transportation System Wireless Sensor Network vehicle localization Gaussian white noise Kalman filteringalgorithm
下载PDF
The Design of Temperature and Pressure Data Collector Based on HART protocol
3
作者 SONG Quan-you GUO Bin 《微计算机信息》 2011年第1期43-44,71,共3页
下载PDF
A Group-Period Phase Comparison Method Based on Equivalent Phase Comparison Frequency 被引量:9
4
作者 杜保强 周渭 +1 位作者 董绍锋 周海牛 《Chinese Physics Letters》 SCIE CAS CSCD 2009年第7期65-68,共4页
Based on the principle of equivalent phase comparison frequency, we propose a group-period phase comparison method. This method can be used to reveal the inherent relations between periodic signals and the change laws... Based on the principle of equivalent phase comparison frequency, we propose a group-period phase comparison method. This method can be used to reveal the inherent relations between periodic signals and the change laws of the phase difference. If these laws are applied in the processing of the mutual relations between frequency signals, phase comparison can be accomplished without frequency normalization. Experimental results show that the method can enhance the measurement resolution to 10-13/s in the time domain. 展开更多
关键词 sea surface nonliear interaction numerical method
下载PDF
Super-High Resolution Time Interval Measurement Method Based on Time-Space Relationships 被引量:8
5
作者 杜保强 周渭 《Chinese Physics Letters》 SCIE CAS CSCD 2009年第10期61-64,共4页
Based on the principle of quantized delay-time, a super-high resolution time interval measurement method is proposed based on time-space relationships. Using the delay-time stability that time and frequency signal tra... Based on the principle of quantized delay-time, a super-high resolution time interval measurement method is proposed based on time-space relationships. Using the delay-time stability that time and frequency signal travel in a specific medium, the measured time interval can be quantized. Combined with the phase coincidence detection technique, the measurement of time can be changed into the measurement of space length. The resolution and the stability of the measurement system are easily improved. Experimental results show that the measurement resolution of the measured time interval depends on the length difference of the double delay-time unit. When the length difference is set up on millimeter level or sub-millimeter level, super-high measurement resolution from hundreds of picosecond to tens of picosecond can be obtained. 展开更多
关键词 sea surface nonliear interaction numerical method
下载PDF
Advances in Application of Models in Soil Quality Evaluation 被引量:1
6
作者 SI Zhi-guo WANG Ji-jie +3 位作者 YU Yuan-chun LIANG Guan-feng CHEN Chang-ren SHU Hong-lan 《Asian Agricultural Research》 2012年第11期89-93,共5页
Soil quality is a comprehensive reflection of soil properties.Since the soil quality concept was put forward in the 1970s,the quality of different type soils in different regions have been evaluated through a variety ... Soil quality is a comprehensive reflection of soil properties.Since the soil quality concept was put forward in the 1970s,the quality of different type soils in different regions have been evaluated through a variety of evaluation methods,but it still lacks universal soil quantity evaluation models and methods.In this paper,the applications and prospects of grey relevancy comprehensive evaluation model,attribute hierarchical model,fuzzy comprehensive evaluation model,matter-element model,RAGA-based PPC /PPE model and GIS model in soil quality evaluation are reviewed. 展开更多
关键词 SOIL QUALITY EVALUATION model APPLICATION
下载PDF
Global Existence of Smooth Solutions of Compressible Bipolar Euler-Maxwell Equations
7
作者 XU Qian-jin LI Xin FENG Yue-hong 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第2期274-283,共10页
The bipolar compressible Euler-Maxwell equations as a fluid dynamic model arising from plasma physics to describe the dynamics of the compressible electrons and ions is investigated. This work is concerned with three-... The bipolar compressible Euler-Maxwell equations as a fluid dynamic model arising from plasma physics to describe the dynamics of the compressible electrons and ions is investigated. This work is concerned with three-dimensional Euler-Maxwell equations with smooth periodic solutions. With the help of the symmetry operator techniques and energy method, the global smooth solution with small amplitude is constructed around a constant equilibrium solution with asymptotic stability property. 展开更多
关键词 bipolar Euler-Maxwell system global smooth solution Moser-type calculus inequalities
下载PDF
Numerical simulation research of microcosmic flaws in masonry arch bridge
8
作者 NING Jin-cheng OU Yi-hong 《通讯和计算机(中英文版)》 2008年第10期18-22,共5页
关键词 数字模拟技术 砌体拱桥 建筑设计 计算机技术
下载PDF
Management of transport of dangerous goods based on networking technology
9
作者 GAO Lian-zhou 《International Journal of Technology Management》 2013年第8期44-46,共3页
Networking is the core area of national strategic emerging industry development of information industry; it will play an important role in national economic development. Currently, it is hot issue of global research a... Networking is the core area of national strategic emerging industry development of information industry; it will play an important role in national economic development. Currently, it is hot issue of global research at home and abroad regardless of the mention of its development of a national strategic level, it is called the third wave of the world information industry following the computer, and internet. 展开更多
关键词 Management of transport networking technology Logistics enterprises
下载PDF
Research on thermode of operation of wisdom Logistics in large data background
10
作者 GAO Lian-zhou 《International Journal of Technology Management》 2013年第12期6-8,共3页
With the rapid development of China' s economy and the accelerating pace of economic globalization, the rapid expansion of trade appears in goods, materials; space to move also will expand in breadth and depth, and t... With the rapid development of China' s economy and the accelerating pace of economic globalization, the rapid expansion of trade appears in goods, materials; space to move also will expand in breadth and depth, and thus the efficiency of the logistics activities, rapid response capabilities and the level of information logistics put forward higher requirements. Meanwhile, the logistics needs of personalization, diversification and sophistication, require that logistics service companies must constantly improve and optimize enterprise business model, and target to develop new logistics services to adapt to changes in the logistics market, and improve the competitiveness of enterprises.Modem logistics enterprises refer to the concept of modem logistics as a guide, and the use of modem logistics and organization of modem logistics technology, it is to provide customers help and reduce logistics costs and improve the level of integrated logistics services to rationalize logistics enterprises. Modem logistics enterprises are in terms of philosophy, mode of operation, services, information technology degree, logistics technology, enterprise systems and others have higher requirements to react quickly, service serialization, standardization of operations, the target of systematic, modem means are the features of the organization which are different from the traditional network of logistics enterprises. 展开更多
关键词 Large Data Wisdom Logistics Operation
下载PDF
A Study of Writing Test in CET-4
11
作者 Siyou Zhang Xia Ning 《Sino-US English Teaching》 2004年第6期14-19,共6页
The paper discusses the "Writing Test" in College English Test - Band Four in two aspects. One is the design of the "Writing" form; the other is the scoring process. From the discussion the paper comes to a conclu... The paper discusses the "Writing Test" in College English Test - Band Four in two aspects. One is the design of the "Writing" form; the other is the scoring process. From the discussion the paper comes to a conclusion that the "Writing Test" in CET-4 should be reformed in two ways: the single style of the "Writing" structure should be changed to various styles in design, and the "global scoring" principle used in marking the writing should be changed to "local scoring". At last, the author suggests some ways of how to put the reforming into reality, 展开更多
关键词 writing test CET-4 style global scoring local scoring
下载PDF
THE HOPE UNDER ENDURANCE----- ANALYSIS OF THE FREEDOM Of THE SHAWSHANK REDEMPTION
12
作者 Liu Ting - ting 《商情》 2011年第2期145-145,共1页
关键词 英语 语法 语言学 自主权
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部