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1.
A coupled experimental investigation and thermodynamic study of the yttrium-hydrogen(Y-H) binary system were carried out to provide more comprehensive and quantitative insights into the key thermodynamic properties of this system. Y-H system in the full range of H/Y = 0–3.0 was investigated by accurate pressure composition isotherm(PCI) measurement to provide credible phase equilibria information and thermodynamic data.The phase boundaries obtained were in agreement with previous experimental data but with improved accuracy.With the guide of the crystal structures, all the solid phases were modelled using the three sublattice model. The Y-H phase diagram and thermodynamic parameters were calculated and assessed with the CALPHAD technique.The obtained results are in very good agreement with our experimental data and the published data reported in literature. The obtained thermodynamic database of Y-H system can be used to predict the hydrogenation behavior and decomposition temperatures of hydrides.  相似文献   

2.
In this paper, Kaixian County, situated in the hinterland of the Three Gorges Reservoir Region, was selected for the case study. Factors of soil erosion were obtained based on the technique of remote sensing (RS) and geographic information system (GIS). Combining with field survey, soil erosion data in the years of 1988, 2000 and 2004 which covered the period from the beginning of the Three Gorges Reservoir Project to nowadays were investigated through the judgment model established on soil erosion intensity. With the function of spatial analysis in the geographic information system, the analysis and appraisal of dynamic soil erosion changes were carried out, and the spatial characteristics of the vicious change were highlighted, and the main causes of the vicious change of soil erosion were explored.  相似文献   

3.
A sodium fluorescence Doppler lidar system has been developed to measure environmental parameters of the middle and upper atmosphere. The lidar system mainly comprises a transmitter system,receiver system,data acquisition and control system and data analysis system. A narrowband 589 nm laser is used to excite sodium atoms in the mesopause region. Excitation of the sodium atoms results in resonance fluorescence,which is collected by the receiver. The temperatures in the mesopause region(about 75-105 km) can be derived by analyzing the Doppler-broadened width of the sodium fluorescence. Observations were made with the lidar system,and the number density of sodium atoms and atmospheric temperature profiles were extracted from the observation data. Comparisons of the lidar temperatures and TIMED/SABER temperatures show good agreement,illustrating the reliability of the sodium fluorescence Doppler lidar measurements.  相似文献   

4.
Different from other similar studies, in this paper, most of the data were excerpted from historical archives and documents, and were used to study the spatiotemporal dynamics of cultivated land resources in China during the last 300 years. It is clear that these data may help reveal land use change dynamics and its regional differences, but they may be problematic due to the constraints of the original data in the Ming Dynasty, Conversion of Land Area for the purpose of collecting land taxes, and the deliberate or inadvertent omission of cultivated land area during land surveys, therefore, such data were adjusted to our need. In processing the data, we made great efforts to analyze the historical context of their sources and reduced the possible errors. The results show that the cultivated land area increased most quickly in the early Qing Dynasty, and slowed down after the middle Qing Dynasty, and then was stable in the late Qing Dynasty until 1949, and has been decreasing since then. It is also found that the cultivated land use varied greatly in different regions. The east of the country was cultivated much more heavily than the west, but in some western provinces cultivated land area increased more quickly. It is considered that the driving factors of such cultivated land area change include the increase of the population, the political issues, and the impacts of wars. Natural environmental factors and the introduction of new crops might also have affected the cultivated land use change in the past 300 years.  相似文献   

5.
Architecture Design of Global Distributed Storage System for Data Grid   总被引:5,自引:0,他引:5  
This paper describes the architecture of global distributed storage system for data grid. It focue on the management and the capability for the maximum users and maximum resources on the Internet, as well as performance and other issues.  相似文献   

6.
This text uses the regional geological investigation data and the remote sensing image data of earthsatellite remote sensing to synthetically analyze the structural system of Taiwan region of China. Authors detection-marked and assurance-marked and divided 5 kinds of structural system of the Taiwan region: ( 1 ) the wreath-shaped structural system, (2) the N-N-E oriented structural system, (3) the S-N oriented structural system, (4) the N-E oriented structural system, (5) the are-shaped structural system. Combination of the texture faces and associated method were adopted to recover and reconstruct the structural evolution sequences and the formation periods. In this paper, problems such as the development process in geology etc. are also discussed, contributing new information to research the structural field of the East Asia and its tectonic plate movements and structural actions inside the land plate .  相似文献   

7.
KF or K2CO3 was added into the 1-butanol-water system and two phases were formed: water-rich phase (water phase) and 1-butanol-rich phase (1-butanol phase). The liquid liquid equilibrium (LLE) data for 1-butanol-water-KF and 1-butanol-water-K2CO3 systems were measured at 25℃ and showed that 1-butanol phase contained negligible salt and water phase contained negligible 1-butanol when the concentrations of KF and K2CO3 in the water phase were equal to or higher than 27.11% and 31.68% , respectively. Thus water could be separated efficiently from 1-butanol-water by adding KF or K2CO3 into the system. A theoretical calculation of LLE data was calculated by using the Pitzer theory to get water activity in the water phase, and by the models, such as the Wilson, NRTL or the UNIQUAC for the 1-butanol phase. For 1-hutanol-water-KF system, the experimental data were found in good agreement with the calculated results by using Pitzer theory and Wilson equa tion, while for 1-butanol-water-K2CO3 system, the experimental data were found in good agreement with the calculated results by using Pitzer theory and UNIQUAC eauation.  相似文献   

8.
A microscopic pushbroom hyperspectral imaging system was developed based on the microscopic technology and spectral imaging technology according to the principle of spectral imager in remote sensing. The basic principle and key technologies of this system were presented and the system per- formance was also analyzed. Some methods and algorithms were proposed to preprocess and nor- malize the microscopic hyperspectral data and retrieve the transmittance spectrum of samples. As a case study, the microscopic hyperspectral imaging system was used to image the retina sections of different rats and get some significant results. Experiment results show that the system can be used for the quantitative assessment and evaluating the effect of medication in biomedical research.  相似文献   

9.
Anti-collision equipments system is developed to solve the collision problems of dam construction equipments, and in the system the determination of equipments' space state is important. A uniform moving equation of equipments is established based on the analysis prediction theory and the movements states of equipments. Method of least square was employed to deal with discrete data of equipments' space position. Fitting equation matched with the movement equation was presented to do data fitting, and a relevant algorithm was given. Applying the fitting equation, current and future space state of equipments can be accurately predicted. Finally, a case is given and results show that numerical values of data were steady and their precision was high. In LongTan dam construction of the equipments antiollision system, applying this method to forecast the equipments' space states and practical running of the system indicate that this method can improve the precision of position, obtain the better forecasting effect and increase the robustness of the system.  相似文献   

10.
<正>To detect the deformation of the tunnel structure based on image sensor networks is the advanced study and application of spatial sensor technology.For the vertical settlement of metro tunnel caused by internal and external stress after its long period operation,the overall scheme and measuring principle of tunnel deformation detection system is introduced. The image data acquisition and processing of detection target are achieved by the cooperative work of image sensor,ARM embedded system.RS485 communication achieves the data transmission between ARM memory and host computer.The database system in station platform analyses the detection data and obtains the deformation state of tunnel inner wall,which makes it possible to early-warn the tunnel deformation and take preventive measures in time.  相似文献   

11.
A highway distress and preventive measures decision support system based on WebGIS and J2EE architecture were studied, and the key issues for the system are presented. Such issues as spatial data and attribute data organization, technology of enhancing user experience, database connection pool were investigated. The feasibility of the theories and methods were tested through the system.  相似文献   

12.
介绍了一套窄脉冲信号采集系统的实现方法,提出并实现了交叉采样提高采样速率的设计方案.对提高系统性能中遇到的模拟设计、高速数字信号接收、信号完整性等做了简要介绍.设计方法对于采用低速采样器件实现高速信号的采样具有借鉴意义.  相似文献   

13.
TD-LTE(time division-long term evolution)终端协议一致性测试是检验TD-LTE终端是否符合协议标准的重要手段。针对目前TD-LTE终端协议一致性测试系统难以实时监控、存储数据和反查异常的问题,分析了数据监控子系统功能模块及测试系统的整体流程,设计了数据监控子系统的体系结构,通过在系统中嵌入模块的方法,实现数据处理模块、网络监视模块和异常反查模块的功能。系统整体测试表明,该数据监控子系统可以实现以上功能,其设计与实现方案合理。  相似文献   

14.
基于DCOM的分布式WebGIS架构与关键技术   总被引:2,自引:1,他引:2  
探讨了基于DCOM(分布式组件对象模型)的分布式WebGIS(网络地理信息系统)架构,及其关键技术的研究和实现.设计了一种新的数据模型SHAPE2D来组织客户端空间数据,并对中间件的设计、空间数据的优化组织、多分辨率显示、空间数据存储和数据库模型与结构等进行研究,提出了WebGIS中空间数据的压缩方法、矢量与栅格传输的综合平衡策略.最后,应用SHAPE2D客户端数据结构以及网络综合平衡策略,基于系统的快速定制机制,建立了房屋土地分布式WebGIS应用系统.该系统验证了本文的各种理论与方法是切实可行的.  相似文献   

15.
本文论证了采用关联规则算法进行数据挖掘,以发现课程之间相关性的可行性。数据挖掘部分采用经典的Apriori算法,并引入了感兴趣度的概念,对挖掘结果进行进一步的清理,从而提高了系统的性能。  相似文献   

16.
利用VB与Matlab混合编程,开发了一套基于PC机的摩擦磨损试验机计算机辅助测试系统.利用Matlab软件强大的数值计算及图形处理函数,实现了试验数据的滤波与动态显示、试验曲线的输出和图形移植,缩短了开发周期.介绍了测试系统的3大功能模块(数据采集模块、数据处理模块、采集数据的滤波及图形输出模块)的基本功能及实现手段,对测试系统软件设计过程中的难点问题,如采样时间控制、动态实时波形图的显示和数据的滤波等问题的编程思路作了详细的论述,并提供了部分源代码.  相似文献   

17.
基于J2EE高速公路网络地理信息系统平台研究   总被引:3,自引:0,他引:3  
探讨了基于J2EE(Java 2 Enterprise Edition)的高速公路网络地理信息系统(webGIS)平台架构及其关键技术,包括高速公路空间数据组织和设计。WebGIS中间件技术,数据库连接池技术,高速公路WebGiS的动态分段技术等.建立了高速公路WebGIS地理信息平台,以惠河高速公路管理为例,介绍了地理信息平台的功能和应用,验证了文中的各种技术与方法.  相似文献   

18.
 基于环境监测和现状调查数据,诊断了洞庭湖区目前存在的主要水环境问题,从水文水情变化、污染来源、环境管理等角度分析了形成以上问题的主要原因,并探讨了相应的解决对策:构建畅通生态水网,增大水环境承载能力;源头控制,减少水型污染物产生;污染源治理和重点区域整治相结合,开展区域内水污染防治;清水入流,降低上游影响;创新环境机制体制,推进生态文明体制改革实践。  相似文献   

19.
商业电子数据交换网的设计与研究   总被引:2,自引:1,他引:1  
以商汇网为例,介绍了一种商业电子数据交换专用网的总体设计和实施方法,研究了设计这类系统时应注意的几个问题,论述了电子商务系统中为提高网络舆效率而采取的一些技术方法。  相似文献   

20.
RFID中间件是RFID的关键共性技术,屏蔽了RFID设备的多样性和复杂性。研究了RFID中间件技术中的数据过滤、数据聚合和信息传递等关键问题,结合JMX和JMS技术,构建RFID中间件,将RFID中间件技术应用到渔船管理系统中,为解决渔船管理中的套牌问题提供了一套解决方案。介绍的渔船身份识别及系统中数据流的管理系统,可以提高渔船相关部门的管理效率。  相似文献   

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