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1.
JavaScript provides the technological foundation of Web 2.0 applications. AJAX (Asynchronous JavaScript And XML) applications have received wide-spread attention as a new way to develop highly interactive web applications. Breaking with the complete-page-reload paradigm of traditional web applications, AJAX applications rival desktop applications in their look-and-feel. But AJAX places a high burden on a web developer requiring extensive JavaScript knowledge as well as other advanced client-side technologies. In this paper, we introduce a technique that allows a developer to implement an application in Java or any.NET language and then automatically cross-compile it to an AJAX-enabled web application.  相似文献   

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This paper presents a brief overview of the European Commission funded Thematic Network (Working Group) “Information Society for All”-IS4ALL (IST-1999-14101). IS4ALL aims to establish a wide, interdisciplinary and closely collaborating network of experts to provide the European Health Telematics industry with a comprehensive code of practice on how to appropriate the benefits of universal design. This paper outlines the project’s main objectives and technical approach in the context of universal access. Published online: 9 April 2002  相似文献   

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The bound on component failures and their spatial distribution govern the fault tolerance of any candidate error-detecting algorithm. For distributed memory multiprocessors, the specific algorithm and the topology of the processor interconnection network define these bounds. This paper introduces the maximal fault index, derived from the system topology and local communication patterns, to demonstrate how a maximal number of simultaneous component failures can be tolerated for a particular interconnection network and error-detecting algorithm. The index is used to design a mapping of processes to processor groups such that the error-detecting ability of the algorithm is preserved for certain multiple simultaneous processor failures  相似文献   

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International Journal of Information Security - When deciding against outsourcing their data to the cloud, organizations often point to security as the primary reason. If cloud is not used as a...  相似文献   

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XML and XML Schema are used in the geospatial domain for the definition of standards that enhance the interoperability between producers and consumers of spatial data. The size and complexity of these geospatial standards and their associated schemas have been growing with time reaching levels of complexity that make it difficult to build systems based on them in a timely and cost-effective manner. The problem of producing XML processing code based on large schemas has been traditionally solved by using XML data binding generators. Unfortunately, this solution is not always effective when code is generated for resource-constrained devices, such as mobile phones. Large and complex schemas often result in the production of code with a large size and a complicated structure that might not fit the device limitations. In this article we present the instance-based XML data binding approach to produce more compact application-specific XML processing code for geospatial applications targeted to mobile devices. The approach tries to reduce the size and complexity of the generated code by using information about how schemas are used by individual applications. Our experimental results suggest a significant simplification of XML Schema sets to the real needs of client applications accompanied by a substantial reduction of size of the generated code.  相似文献   

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FEC (Forward Error Correction) mechanisms improve IP content transmission reliability through the recovery of packets lost in transmission. Opposite to ARQ (Automatic Repeat Request), FEC mechanisms are especially suited to unidirectional environments or to multicast environments where multiple receivers perceived different channel losses, thus making difficult the implementation of mechanisms based on feedback information. Among the different types of FEC codes, this paper presents a thorough performance evaluation of LDPC (Low Density Parity Check) codes, based on an implementation developed by the authors, according to the specifications defined by RFC 5170 for the usage of LDPC codes by push content applications based on the FLUTE protocol. LDPC codes provide a good trade-off between performance and complexity, hence, they are appropriate for mobile applications. Contributions of this paper include tests conducted with commercial mobile phones connected to the push content download server over a Wi-Fi network. The evaluation highlights the advantages of using packet level FEC encoding in file transmission over unidirectional networks and provides with a comparison between two kinds of LDPC structures: Staircase and Triangle. This is accomplished by calculating the inefficiency ratio of these LDPC structures in different environments. Results show that the implemented LDPC codes can provide inefficiency ratios close to one when the different coding parameters (as the code rate or the number of blocks) are configured to an optimal value that depends on the packet loss rate.  相似文献   

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Rich Internet applications have removed most of the constraints of Web 1.0 while giving users more responsiveness and advanced browsing and interaction experiences. These new horizons, however, raise many challenges for people with disabilities or using limited hardware and software technologies, whose risk to be excluded from the benefits deriving from advanced web applications. To address this problem, WCAG 2.0 guidelines have been released as the newest World Wide Web Consortium recommendation for accessible web content, and WAI-ARIA is a candidate recommendation which provides reference specifications for accessible rich Internet applications. However, both specifications contain a huge amount of information that often discourages most web designers from dealing with accessibility issues. Moreover, guidelines are suitable and usually adopted to judge a design solution a posteriori, but they do not suggest how to face a design problem constructively. This paper proposes a design pattern language for accessibility. The language can be regarded as a universal design resource for helping web designers create accessible rich Internet applications compliant with the most recent standards. Knowledge representation through design patterns reflects the problem-solving approach usually followed by software and web designers, while pattern organization in a structured language aims to guide web designers throughout the design process. The language has been implemented as an accessible rich Internet application itself, thus allowing designers with disabilities to participate in web design. In order to evaluate the design pattern language, a three-step process was carried out including: (1) a heuristic analysis with a group of human–computer interaction experts, (2) a survey study with a group of web designers, and (3) a validation on the field with two designers who have been requested to apply the language in real design cases.  相似文献   

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数据挖掘技术可以从大量的数据中发现某些有价值的知识.而将软件源码作为一种特殊的数据,在其上应用数据挖掘技术进行源码层次上的信息挖掘,已成为一个新颖而重要的课题.将对软件源码上的数据挖掘技术从各领域的应用、数据挖掘方法以及当前发展水平等主要方面展开介绍,并详细剖析当前此领域的制约因素,提出未来此领域的发展方向.  相似文献   

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为了采用计算方法研究手性化合物,为了通过结构.活性相关性研究预测与手性有关的性质,本文提出了采用σ和π的残余电负性之和作为原子属性的构象独立手性指数.该手性指数衍生于原子径向分布函数,包含分子几何和原予属性的信息,能够区分对映体.将构象独立手性指数应用于1个包含48对手性氨醇对映体的数据集,该数据集为苯甲醛与二乙基锌发生加成反应的催化剂,每个催化剂均产生特定绝对构型的反应主产物.采用相向传输神经网络建立了手性氨醇催化剂的构象独立手性指数与反应主产物绝对构型的相关性模型,得到了满意的预测结果.对于独立的测试集,90.0%的催化剂被正确地预测;对于训练集,89.5%的催化剂被正确地识别.  相似文献   

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This research proposes a simple economical broadband circularly polarized antenna for universal ultra‐high frequency (UHF) RF identification (RFID) readers. The antenna utilizes a folded plate, a two‐corner truncated parasitic patch, and a ground plane. The folded plate, which is fabricated from one single plate, consists of a two‐corner truncated main patch, a wall patch, and a feed line, where the main patch is perpendicular to the wall patch, which is in turn perpendicular to the feed line. The folded plate enables currents to flow with a phase difference. The simulation results achieved an |S11| < ?15 dB of 805–966 MHz (18% bandwidth), a 3‐dB axial ratio (AR) bandwidth of 834–962 MHz (14% AR bandwidth), and a gain higher than 8.6 dBic. The measured results obtained an |S11| < ?15 dB of 806–970 MHz (18%), a 3‐dB AR bandwidth of 816–963 MHz (16%), and a gain greater than 7.8 dBic. The proposed antenna is applicable for universal UHF RFID readers as it covers the entire operating UHF RFID frequency range of 840–960 MHz. The parametric study and evolution of the proposed antenna are detailed in this research paper as well. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:575–587, 2016.  相似文献   

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语义级的自动查错一直是汉语文本自动校对技术的难点.针对汉语文本中的语义搭配错误,提出了一种基于<知网>义原搭配的有效的自动查错方法,主要包括语义知识库的构建和自动查错算法.语义知识库的构建分为两步:①根据规则从训练语料中统计出大量的动词与名词之间的二元搭配组合,并利用互信息等因素筛选记录;②利用<知网>对词语义项的义原描述(对于动词抽取其义项中的主义原,名词抽取其义项中的主义原和常见的4个辅助义原),将动词与名词的二元搭配组合转变为义原之间相互制约的多元组合.在语义知识库的基础上设计相应的自动查错算法.实验结果显示,该方法的召回率为35%,精确率为82.3%,具有较好的应用前景.  相似文献   

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相对于单一类型的代码异味,代码异味共存现象更具危害性。已有实证研究大多聚焦于分析桌面应用程序中代码异味的共存现象,缺少对Android应用程序中代码异味共存现象的研究。为了研究Android应用程序中代码异味的共存现象,并与桌面应用程序中代码异味共存现象进行比较,分别对285个Android应用程序和30个桌面应用程序进行检测,对检测出来的10种异味进行分析。首先,根据检测结果计算受到多种异味影响的类的百分比。然后,使用公式计算代码异味共存的频率,最后,使用Spearman相关系数分析代码异味共存与应用程序规模的关系。结论如下:a)在Android应用程序中受到一种以上代码异味共同干扰的类占有异味的类的总数的31.04%;b)在两个平台的应用程序中,两对代码异味brain class—brain method和god class—brain method共存的频率较高;c)一种异味、两种异味共存、三种异味共存与Android应用程序的规模具有较强的相关性。  相似文献   

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李辉  牛怿 《计算机应用》2005,25(10):2428-2430
引进校验码可增强Web认证系统的安全性,校验码基于位图格式,由系统随机产生,图像识别环节的引入是增强安全性的关键。已在多个实际工程项目中成功应用,该原理同样适用于其他端到端即时通信的认证系统。  相似文献   

16.
Wireless sensor network (WSN) applications sense events in situ and compute results in-network. Their software components should run on platforms with stringent constraints on node resources. To meet these constraints, developers often design their programs by trial-and-error. Such manual process is time-consuming and error-prone.Based on an existing task view that treats a WSN application as tasks and models resources as constraints, we propose a new component view that associates components with code optimization techniques and constraints. We provide a visualization mechanism to help developers select code optimization techniques. We also develop algorithms to synthesize components running on nodes, fulfilling the constraints, and thus optimizing their quality.  相似文献   

17.
Business applications automate various business processes within an organization. Business analysts frequently modify business processes to maintain a competitive edge. Estimating the time needed to modify a business process is not a trivial task, since changes to the business process result in changes to the source code of which the business analyst has limited knowledge. We propose a change impact metric which estimates the code to be modified as a result of a business process change. We demonstrate the effectiveness of our proposed change impact metric through a case study, using seven large business applications from the OFBiz open source project.  相似文献   

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为加快量子遗传算法的参数更新速度,简化遗传操作步骤,提出了一种基于通用量子门的量子遗传算法(Quantum Genetic Algorithm with Universal Quantum Gate,UQGA)。该方法以通用量子门为逻辑计算单位,对染色体进行遗传操作。利用Hadamard门进行基础变换;通用量子门通过新的旋转角度函数,对各个基因位进行选择、变异操作;通过求解适应度函数,得到全局最优解;同时,算法经数学证明是收敛的。该算法应用到函数极值搜索和Iris数据集特征选择中。实验结果表明,UQGA具有较好的全局搜索和特征选择性能,尤其是在收敛速度、运算时间和分类准确率方面明显优于普通量子遗传算法和普通遗传算法。  相似文献   

20.
As there are huge amounts of Global Positioning System (GPS) data points measured in the Qinghai-Tibet Railway (QTR) with a length of 1142 km, it was inevitable that some measuring errors existed due to various situations in measurement. It is very important to develop a method to automatically detect the possible errors in all data points so as to modify them or measure them again to improve the reliability of GPS data. Four error patterns, including redundant measurement, sparse measurement, back-and-forth measurement, and big angle change, were obtained based on expert knowledge. Based on the four error patterns, four algorithms were developed to detect the corresponding possible errors in data points. To delete the repetitive errors by different algorithms and effectively display the possible errors, an integrated error-detecting method was developed by reasonably assembling the four algorithms. After four performance indices were given to evaluate the performance of the error-detecting method, six GPS track data sets between seven railway stations in the QTR were used to validate the method. Thirty-eight segments of some sequential points that are possibly wrong were found by the method and fourteen of them were confirmed by measurement experts. The detecting rate of the method was 100% and the duration time of the detecting process was less than half an hour compared with the 94 h manual workload. The validation results show that the method is effective not only in decreasing workload, but also in ensuring correctness by integrating the domain expert knowledge to make the final decision.  相似文献   

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