Defining and assessing safety functions performed by people

The design and safety assurance of systems require good requirements management. Within the nuclear industry, Safety Functional Requirements (SFRs) have become well-understood and form a central role as the design and safety case evolve. There are established engineering methods for the identification, classification, format and substantiation of SFRs. Despite striving for engineered protection systems, humans continue to provide, support and contribute to this protection. Identifying the human ‘component’ in systems has advantages in terms of integrating with non-Human Factors disciplines, improving awareness of human factors within safety and design, and ultimately making system design safer. This paper describes the identification and assessment of safety functions that are performed by people. It presents some of the difficulties in trying to model and predict human behaviour compared to engineered system components. With emphasis on the nuclear industry, the paper discusses how the relationship between detailed hazard analysis and formally vested Operating Rules can be improved through the identification of safety functions performed by people.     

Analysis of variance of Gabor filter banks parameters for optimal face recognition

Gabor filter banks constitute a very robust tool to extract discriminant information from a visual scene. After the now “classical” bank with 5 frequencies and 8 orientations proposed by Lades et al. and Wiskott et al., many other parametrizations of a Gabor filter bank have appeared. In order to find the optimal parametrization for a face recognition experiment, we have performed a 6-way analysis of variance of Gabor parameters using FERET, FRAV2D, FRAV3D, FRGC and XM2VTS face databases, including frontal and turned poses, facial expressions, occlusions and changes of illumination. Considering independent criteria to find the optimal Gabor filter bank, the bank with the highest recognition rate was found to have 6 frequencies and narrower Gaussian widths in the space domain. These results were obtained with Mahalanobis distance for a k-NN classifier, with analytical and holistic Gabor feature vectors. Moreover about 20% of the banks studied here obtained in average a better performance than the classical bank. For most of the databases considered, the highest recognition rates have been achieved with analytical representations (frontal images, images with turns or occlusions), with a holistic preponderance for images with gestures or changes of illumination. The inferiority found for holistic Gabor representations versus their analytical counterparts can be explained for the intrinsic redundancy and the size of the feature vectors of this kind of representation.     

Defining and validating metrics for assessing the understandability of entity–relationship diagrams

Database and data model evolution cause significant problems in the highly dynamic business environment that we experience these days. To support the rapidly changing data requirements of agile companies, conceptual data models, which constitute the foundation of database design, should be sufficiently flexible to be able to incorporate changes easily and smoothly. In order to understand what factors drive the maintainability of conceptual data models and to improve conceptual modelling processes, we need to be able to assess conceptual data model properties and qualities in an objective and cost-efficient manner. The scarcity of early available and thoroughly validated maintainability measurement instruments motivated us to define a set of metrics for Entity–Relationship (ER) diagrams. In this paper we show that these easily calculated and objective metrics, measuring structural properties of ER diagrams, can be used as indicators of the understandability of the diagrams. Understandability is a key factor in determining maintainability as model modifications must be preceded by a thorough understanding of the model. The validation of the metrics as early understandability indicators opens up the way for an in-depth study of how structural properties determine conceptual data model understandability. It also allows building maintenance-related prediction models that can be used in conceptual data modelling practice.     

Using NOAA AVHRR imagery in assessing water quality parameters

Abstract

The Advanced Very High Resolution Radiometer (AVHRR) instrument, carried by the NOAA-TIROS/N series of operational meteorological satellites can, on a routine basis, provide observational data which allow interpretation in terms of parameters related to water quality. In principle, some, though not all of the algorithms applied to Coastal Zone Colour Scanner data can be transformed for use with AVHRR observations. In combination with the operational character of the NOAA satellites this opens up the way to applications in monitoring of open sea and inland waters. Algorithms and results for some examples of such potential applications are presented.     

动态网站与静态网站的比较研究

如果网页在服务器端需要执行代码则属于动态网网站,动态网站的网页会随客户端请求的不同返回的网页也不同,也就是说传往客户端的网页是动态生成的。若网页在服务器端不需要执行代码则属于静态网站,此时传往客户端的网页是事先编好存在于服务器上的网页文件,它们是永远不变的。动态网站也可以采用静动结合的原则,适合采用动态网页的地方用动态网页,如果有必要使用静态网页,则可以考虑用静态网页的方法来实现。     

Building presence in an online shopping website: the role of website quality

This study explores how sellers’ website quality influences buyers’ perceived presence, which in turn affects website identification and purchase intention. The results of a conceptual model, with data collected from TaoBao, demonstrate that information and service quality are positively related to social presence, and system and service quality are positively related to telepresence. Furthermore, information and service quality increase website identification, but system quality does not. Finally, social presence positively affects website identification and purchase intention, while telepresence only positively affects website identification. These results bridge the research gap about the formation of presence in an online shopping context.     

基于Siteserver CMS的网络课程建设与站群管理

分析了现有课程网站建设存在的问题,提出使用Siteserver CMS建设课程网站,探索了课程网站建设方案和站群平台管理模式,实现了教师管理课程网站的新模式和课程网站的多种功能,在更大程度上发挥了信息化技术手段在人才培养中的作用。     

The qualitative parameters of chemical processes being unmeasurable by flow devices: Real-time estimation methods

This paper considers virtual measurement methods for the qualitative parameters of chemical processes to-be-used in industrial automation systems. The specific features of some virtual measurement methods, corresponding algorithms and application domains are outlined and analyzed.     

An assessment of website password practices

Password-based authentication is frequently criticised on the basis of the ways in which the approach can be compromised by end-users. However, a fundamental point in the defence of many users is that they may not know any better, and lack appropriate guidance and support when choosing their passwords and subsequently attempting to manage them. Given that such support could reasonably be expected to come from the systems upon which the passwords are used, this paper presents an assessment of password practices on 10 popular websites, examining the extent to which they provide guidance for password selection, enforce restrictions on password choices, and support easy and effective recovery or reset if passwords are forgotten. The findings reveal that the situation is extremely variable, with none of the assessed sites performing ideally across all of the assessed criteria. Better efforts are consequently required if password practices amongst the general populous are expected to improve.     

The negative impact of saturation on website trustworthiness and appeal: A temporal model of aesthetic website perception

Previous research on the perception of websites has shown that users' impressions of websites generated in ultra-rapid display durations (50 ms) correlate with their assessment after longer display durations. Based on the importance of color saturation in the design of websites, we present a 2 ✕ 3 ✕10 study design in which participants either assessed highly saturated or desaturated versions (between-subjects) of 50 websites coming from 10 content domains. All websites were presented three times to each participant in varying durations (50 ms, 500 ms, and 10 s), and each site was rated regarding its trustworthiness, visual appeal, and perceived usability. In contrast to a large body of research describing positive effects of higher saturated colors, our results show that these findings cannot be generalized to website perception, as we found negative effects of saturation depending on the content domain. Furthermore, we propose a temporal model of website perception based on the results in which users first evaluate the visual appeal of a website, followed by a continuous re-assessment of apparent usability, and lastly its trustworthiness. The results have broad implications for the design and presentation of information using digital media.     

利用CSS轻松为网站换肤

为网站"换肤",或网站为用户提供"换肤"选择,可以大大吸引用户的眼球,同时也能提高网站的知名度。文章详细介绍了利用层叠样式表CSS来实现这一技术的几种常用方法,并分析了每种方法的优、缺点和适用范围,通过这些方法可让建站者轻松地实现网站外观的改变,即换肤。     

工业现场远程监测网站的设计与实现

通过利用一个工业现场实例来介绍如何构建基于Internet的远程检测网站，着重介绍了工业现场远程检测网站的总体构架，详细论述数据库和网站的构建，从而为建设复杂的工业现场远程监控网站提供一定的借鉴。     

网站开发的五层构架模块化设计

网站项目设计一般根据项目规模、安全要求和团队工作方式等分别采用不同层次的设计构架,常用的构架有二层模型和三层模型。文章通过ASP.NET4.0(C#)介绍五层构架模块化网站设计方法。从系统的安全性和技术层面把系统横向分解为五层构架模式,再从业务功能考虑把系统纵向分块,使得技术层次更加分明,模块耦合度更低,模块可重用性更高。五层构架模块化设计把业务逻辑和数据库严格与界面分开,系统安全得到保障,这是网站项目开发的理想构架模型。     

新型电子商务网站的研究与设计

目前我国中小企业主要使用综合搜索引擎,门户网站和B2B网站这三种主要渠道进行网络营销,据统计我国现有B2B网站数量达到3000多家,显而易见,电子商务资源已经很庞大了,如何让企业用户整合利用好这么庞大的信息资源呢,于是提出了电子商务的一种新思想:利用计算机自动完成对其它网站的信息搜索和信息发布.本文在分析了这种网站的基本功能后,给出了数据库的基本设计方案,并就一些关键技术难题给出了解决方案.     

网站文件保护系统的研究与实现

网站因需要被公众访问而暴露于因特网上,容易成为黑客的攻击目标,因此需要专门的网站文件保护系统来保障网站内容的安全.分析了网站文件保护系统的模型,对组成模型的3个部分进行了功能说明,然后分析了文件保护的原理,介绍了网站文件保护系统的组成和功能,描述了目前网站文件保护系统使用的3种技术:外挂轮询、核心内嵌、事件触发,并对这3种技术进行了比较.最后给出一个网站文件保护系统的设计方案,并对该方案进行了测试.     

建立基于Web的认证管理系统

主要阐述了如何建立基于Web的认证管理系统。通过中化阳光认证中心网站的建设,提出了认证管理网站建设的思路。在实施过程中,充分利用信息技术的成果,建立了后台数据库支持的信息发布系统和信息反馈系统,为建立适合中国国情的认证管理系统进行了有益的尝试。     

Optimal design of link structure for e-supermarket website

The objective of this research is to optimize the link structure of webpages for an e-supermarket. Customers are looking for greater convenience in shopping when they visit the website of an e-supermarket, while e-supermarket managers prefer webpages that contain information about profitable products to be visited more frequently. In order to balance the interests of both parties and to aid the webmaster in updating the website regularly, we present a mathematical model with the objective of minimizing the overall weighted distances between webpages. An updating algorithm is used to determine the distance between pages. It is proved to be more efficient under certain special circumstances. We propose the statistical Hopfield neural-network and the strategic oscillation-based tabu-search algorithms as solving methods. The former is appropriate for optimizing small-scale problems. The latter is good at solving large-scale problems approximately. The preliminary validity of the model and the performance of the algorithms is demonstrated by experiments on a small website and several large websites, using randomly generated data. The destination pages that customers and website managers preferred are proved to be more accessible after optimization.