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1.
This paper discusses how to design and implement a security subsystem, which based on the Role-based Access Control technology. By taking a teaching web system as a practical example, the paper establishes an access control matrix, so dynamic menu, page jump, and data access control are loaded. The experimental shows that, the system can controls the access authorized data, and to avoid the illegality access. The practicability and robust in the system is evident.  相似文献   

2.
As the important method and instrument of agile manufacture,the technology of distributed collaborative design and manufacturing has become the hotspot of manufacturing. The basic concept and key technologies of IP_VPN are introduced in this paper,and a collaborative design network model based on IP_VPN is presented. Distributed collaborative design is a multi_user,multitask involved system, which is consisted of lots of collaborative processs,so the network security is the key of distributed collaborative design. We research on the security of collaborative design network based on IP_VPN, hence get a conclusion:we can construct an economical?practical and secure collaborative design network system by the application of data encryption,user authentication and access control based on the role,etc.  相似文献   

3.
随着Internet的迅速发展和Web技术的广泛应用,出现了许多基于Web工作方式和MVC设计模式开发的大型应用系统。通过分析目前流行的MVC模式的工作原理和性能特点以及研究基于MVC和浏览器/服务器(B/S)多层体系结构,在J2EE开发环境下采用JSP、Servlet、EJB等核心技术对粮油检验信息管理系统进行了框架设计。  相似文献   

4.
上海市农业科学院庄行综合试验站(以下简称“院综合试验站”)信息管理平台的开发源于院信息化建设的需要,也是为了整合试验站的资源,进一步有效提高试验站生产资料的利用率。基于院综合试验站的信息管理建设要求,本研究体现了以MVC模式为核心搭建院信息管理平台的理念。平台基于B/S结构,以.NET和XML为开发底层,充分发挥MVC模式优越性、SQL SERVER数据库高效、安全与容灾特性,合理设计平台框架,实现了各种信息的综合管理功能。本平台可以静态发布所有的相关栏目,平台充分考虑安全性问题,运用用户角色定制和功能模块定制赋予的实现,使平台内的用户始终在可掌控的范围内进行相关管理与操作。  相似文献   

5.
The education modes and contents involved in the management of distance education are first analyzed in the paper, and the preliminary implementation based on CERNET and Internet is followed. The techniques of WWW servers efficient access to database and system security are presented in addition.  相似文献   

6.
Apache Struts is one of the most popular open source framework for Web applications and developments using MVC Model2 architectural pattern. Using the Information Technology to improve the efficiency of education service is emergent. The aim of this paper is to demonstrate the design and realization of a platform system software based on Apache Struts framework. By briefly analyzing the extra requirement in higher education service, an architecture based on MVC design pattern is presented. Some core technologies used in the platform system software, such as Struts Tiles and Struts Menu etc, are proposed in details by the end. Because of its struts-based fundamental architecture and running mechanism, the platform system software made a certain performance advantage and largely reduced the developing period.  相似文献   

7.
平原区土地生态安全评价——以延津县为例   总被引:3,自引:3,他引:0  
健康的土地生态系统是人类健康和经济发展的决定性因素。随着人类对土地的利用强度和范围日益增大,在尊重生态规律的基础上,对区域土地生态安全性进行评价显得尤为重要。本研究以平原区的延津县为例,基于P-S-R概念框架模型,建立了包含17项指标的区域土地资源生态安全评价指标体系。运用层次分析原理和土地生态安全模型对该区2006-2008年的土地生态综合安全值进行计算。研究表明,制约平原区土地生态安全的主要因素有:环保支出占GDP的比重、农药使用量、耕地面积比重和人口密度等;2006-2008年延津县区域土地生态状况处于敏感级,且逐年好转。最后,提出改善平原区土地生态安全的建议。  相似文献   

8.
When prominence of security problems increasing,it is of importance to savethe sensitive electronic documents into database. The user-role mechanism is employed in the process of managing documents. However, it can't provide the flexibility of authorized access because of the dynamic generating particularity of the electronic documents which need maintaining continually. A tree model of entity authorization is introduced based on discretionary access control mechanism. The approach can grealty simplify the authorization, increase the flexibility and is more accordant with the practical requirement of enterprises.  相似文献   

9.
土地资源生态安全研究综述   总被引:2,自引:1,他引:2  
土地资源生态安全已经成为当前土地资源可持续利用研究关注的热点问题,笔者在归纳了生态安全概念与特征的基础上,进一步阐述了土地资源生态安全的内涵、驱动因素、评价框架与方法。指出土地资源生态安全主要包括两个方面:一是土地生态系统的结构功能处于健康和平衡的状态;二是能够为人类社会可持续发展提供稳定、均衡、充足的供给。这一状态的实现,需要自然、经济、社会三大驱动因素共同推进,协调发展,其中,经济因素和社会因素对土地资源的影响远远超过自然因素。在评价框架方面,阐述了PSR、DPSIR、DPSER、“自然-经济-社会”4种体系的来源及应用。关于评价的方法,笔者分别对数学模型法、生态模型法、景观生态模型法、数字地面模型法4类方法的优缺点进行了概括总结,并提出了近年来一些新兴的评价方法。最后,笔者对土地资源生态安全研究趋势进行了展望:(1)以生态功能区划为基础,制定具有针对性、体现差异性的土地资源生态安全评价指标体系,并确定生态安全阈值;(2)注重开展干旱区、风沙区、喀斯特地区、水土流失地区、高原山区等典型区域的土地资源生态安全格局研究与未来状况的动态预警研究;(3)在评价方法上加强地理信息技术相结合;(4)探索新的评价方法,以便更好把控土地资源生态安全状况,实现土地资源的永续利用。  相似文献   

10.
农产品质量安全影响因素研究综述   总被引:3,自引:1,他引:2  
农产品质量安全是政府和全社会关注的焦点。通过文献分析,梳理了基于政府保障视角的农产品质量安全宏观影响因素和基于供应链保障视角的农产品质量安全中微观影响因素,包括法律法规体系、标准体系、检验检测体系、监管体系、供应链组织模式、信息传递、收益分配、认知与意识、知识与技术以及信誉。建立了农产品质量安全影响因素模型,评述了宏观因素与中微观因素的相关关系,并指出进一步研究的方向。  相似文献   

11.
12.
Engine test-bed experiments are the main means of engine performance test, whose necessary developing trend is to apply measurement and monitoring system based on the computer. This paper introduces alteration for engine test-bed experiment system. By adopting data acquisition system, using web and ftp technique, computer-controlling and remote monitoring in real-time are realized. And the details of singlechip are mainly discussed based on data acquisition system, testing-software, web and ftp technique. The improved system realizes automation of engine test-bed experiment and data processing. It can save time and manpower, increase the productivity and improve the working condition. Especially the interface of system software developed by Delphi under Windows is simple, clear and easily dealt. The practical application proves that the new system has good value for engineering.  相似文献   

13.
农业信息网站服务质量评价指标优化研究   总被引:2,自引:2,他引:0  
提高农业信息网站服务质量是有效解决农业信息化发展瓶颈的方法之一。科学的网站服务质量评价,可以提高用户获取信息的效率,同时网站设计者通过了解影响其服务质量的主要因素,可以优化网站资源配置。笔者参考服务质量管理的有关原理和已有的指标设计方法,构建了一个农业信息网站服务质量评价通用模型,利用R型系统聚类法探索描述性指标项优化问题,以避免指标项之间存在的相关、重复情况,最后以40个茶叶信息网为实验对象进行数据采集与分析,构建农业信息网站服务质量评价影响因素的多元回归模型,得出在信息服务系统构建过程中影响信息服务质量的重要因素。  相似文献   

14.
DAI Wei 《保鲜与加工》2006,(5):120-123
With the rapid development of wireless network and mobile computing,the security of network becomes more important.As one of wireless mobile network,mobile Ad hoc network has new vulnerabilities that do not exist in a fixed wired network,and is susceptible to attacks.This paper introduces some methods which used in intrusion detection system and provides a new model of system based on multi-layer integrated distributed technology,especially recommend the protocol analyzing method in this system.  相似文献   

15.
The submodel describing benthic biology including a bioturbation module as incorporated in the European Regional Seas Ecosystem Model (ERSEM) is discussed. It is linked to a nutrient dynamic model. The structure of the benthic model food web is presented. There are four macrobenthic functional groups, meiobenthos and aerobic and anaerobic bacteria. The modelling uses ‘standard organisms’ as basic building blocks. The choice of parameter values is discussed. The results demonstrate the dependence of the benthic system on the pelagic system. The importance of features such as predation within functional groups for stability of the system is investigated. Detritus input from the pelagic system and detritus recycling is most important in the benthic food web. The web of carbon and nutrient fluxes through the system is analysed. On the basis of the food web analysis, the trophic positions of the functional groups are calculated. Besides the benthic biology, the mathematical formulation of the bioturbation and diffusion enhancement is discussed. Macrobenthic presence and activity enhance diffusion in the sediment and contribute essentially to vertical transport of particulate matter. This is of great importance for the vertical distribution of detritus, and as a consequence, for microbial activity in the sediment layers.  相似文献   

16.
基于1982—2016 年的气候模式数值预测产品资料,整理分析生成未来45 天北半球500 hPa 高度场和本地气温、降水资料,应用降尺度方法和PP、MOS预报工具建立了预报模型及其业务系统平台。结果表明:业务系统平台构建必须考虑系统结构和功能的先进性、数据存储传输备份的经济性、系统管理的可维护性;此外,还要兼顾前瞻性、开放性、稳定性、安全性和拓展性。系统模块编制采用前端网页、后端程序、模型—视图—控制器的模式和通用的通信协议技术。适合青海高原气候模式解释应用的降尺度方法是车氏多项式、EOF经验正交函数分解和预报量的分区。2012—2016 年青海35 个样本的月降水量、51 个样本的月平均气温预报建模试验的平均评分分别为64%和75%,预报试验获得较高评分的关键是选择最好的因子构建方案和制作预报的回归预报方法。  相似文献   

17.
区域粮食安全度量研究 ——以重庆市万盛区石林镇为例   总被引:1,自引:1,他引:0  
随着经济的快速发展,工业化、城镇化的快速推进,粮食安全问题日益突出,对区域粮食安全进行度量研究,进而建立起合理的区域粮食安全度量模型尤为重要。文章基于粮食产量波动系数、最小人均耕地面积、耕地压力指数建立了综合区域粮食安全度量模型,并以重庆市万盛区石林镇为例,进行动态研究及预测,结果表明:石林镇粮食安全系数呈下降趋势,在未来5年内还有恶化的趋势。针对动态分析及预测结果,提出了相应的调控措施。  相似文献   

18.
Decision making of sewage treatment process directly affects the accuracy and efficiency of the process selection. An optimized fuzzy decision method is proposed based on fuzzy decision and contrast weighting method. Moreover, a web based decision making support system for the selection of sewage treatment process is developed with the Apache+PHP+MySQL development environment. The system had realized the online decision making for sewage treatment process, and enhanced accuracy and reduced the decision making time.  相似文献   

19.
In order to satisfy the demand of the double-deck traffic in city, a concrete box girder model with rectangular web openings was designed with ratio of 1:6. Experimental study was carried out to investigate the flexural capacity of the model girder with double uniformly distributed load. The finite element model was established based on the experiment and the results agreed with measurement results. The effect of the web openings on the girder was explored. The results demonstrated that the deflection caused by load on bottom plate of box girder was 9.7% more than that of load on the top plate. The deflection of girder with web opening is 22.9%~28.1% greater than that of girder without web opening. Compared with girder without web opening, the shear lag of girder with web opening increased, of which the maximum value was 62.0% in various working conditions. simply-supported concrete box girder with web openings under double uniformly distributed load affect the flexural capacity.  相似文献   

20.
大数据与安全可视化   总被引:1,自引:0,他引:1  
IT技术的飞速发展开启了大数据时代。海量的数据信息带来更多的数据价值的同时,各类安全问题也随之而来。通过数据可视化技术能够帮助充分全面并且及时地找出系统中可能存在的安全威胁,评估系统安全,保证基础设施的安全。研究从数据角度出发,结合大数据的特征对安全数据进行分类,并对当前已存在的针对不同安全数据进行可视化的工具及技术进行总结,使得能够将已成熟的数据安全可视化技术用于大数据安全的研究,最后对未来的发展趋势进行了展望。  相似文献   

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