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1.
Context-awareness enables applications to provide end-users with a richer experience by enhancing their interactions with contextual information. Several frameworks have already been proposed to simplify the development of context-aware applications. These frameworks are focused on provisioning context data and on providing common semantics, definitions and representations of these context data. They assume that applications share the same semantic, which limits the range of use cases where a framework can be used, as that assumption induces a strong coupling between context management and application logic. This article proposes a framework that decouples context management from application business logic. The aim is to reduce the overhead on applications that run on resource-limited devices while still providing mechanisms to support context-awareness and behavior adaptation. The article presents an innovative approach that involves third-parties in context processing definition by structuring it using atomic functions. These functions can be designed by third-party developers using an XML-based programming language. Its implementation and evaluation demonstrates the benefits, in terms of flexibility, of using proven design patterns from software engineering for developing context-aware application.  相似文献   

2.
Considering the constrained resources of mobile devices, a thorough performance evaluation of a mobile application is crucial. However, performance evaluation in the mobile domain is still a manual and time‐consuming task. The diversity of mobile devices only increases the complexity of this task. We propose EPE‐Mobile, a framework to automate early performance estimation in mobile applications. It is composed of a configurable library of basic operations and an engine that automatically creates a synthetic program based on the specification of a new app. The synthetic program that EPE‐Mobile generates provides feedback for mobile developers at the first design stages and before the actual implementation of a new application. The fast evaluation can also guide developers in optimizing their applications or in choosing devices with the best trade‐off between cost and performance to run a given application. Finally, developers can reuse the data collection infrastructure of the framework to collect performance data during all development stages. We validate the proposed framework using 4 applications from the Android Play Store. Based on their specifications, 4 synthetic programs were generated and executed on different devices. We compared the results to those obtained from the execution of the actual applications in the same devices. Experimental results show that it is possible to create synthetic applications with similar behavior to that of real applications and, thus, classify devices based on the actual application needs. The framework uses aspect‐oriented programming to collect the metrics of interest. This approach provides increased modularity and separation of concerns, thus facilitating the improvement of the framework itself, by adding other metrics or basic operations.  相似文献   

3.
《Information & Management》2002,39(6):491-502
Data warehousing is one of the key developments in the information systems (IS) field. While its benefits are plentiful, some organizations are receiving more significant returns than others. The types of returns can vary in the impact they have on the organization and the ease in which they can be quantified and measured. This article presents a framework that shows how data warehouses can transform an organization; it also offers a compelling explanation for why differences in impact exist. Case studies of data warehousing initiatives at a large manufacturing company (LMC), the Internal Revenue Service, and a financial services company (FSC) are presented and discussed within the context of the framework. The analysis shows that the benefits that each company received can be tied to the way in which it conforms to the framework.  相似文献   

4.
An earlier review reported a dozen cases where ergonomics applications had resulted in cost savings. A large number of publications which refer to the topics of the cost-effectiveness and cost-benefits of ergonomics can now be found. However, data showing the value of ergonomics applications remain scarce. Cost-benefit and cost-effectiveness studies are difficult to conduct for a number of reasons. While it is unlikely that the general case for the value of ergonomics can be proven, ergonomists must be in a position to discuss the potential costs and benefits of their work with clients. The Business case model is suggested as one way to structure an analysis of where a potential ergonomics application might reduce the risks to costs or the possibility of lost benefits.  相似文献   

5.
Billions of Linked Data triples exist in thousands of RDF knowledge graphs on the Web, but few of those graphs can be queried live from Web applications. Only a limited number of knowledge graphs are available in a queryable interface, and existing interfaces can be expensive to host at high availability. To mitigate this shortage of live queryable Linked Data, we designed a low-cost Triple Pattern Fragments interface for servers, and a client-side algorithm that evaluates SPARQL queries against this interface. This article describes the Linked Data Fragments framework to analyze Web interfaces to Linked Data and uses this framework as a basis to define Triple Pattern Fragments. We describe client-side querying for single knowledge graphs and federations thereof. Our evaluation verifies that this technique reduces server load and increases caching effectiveness, which leads to lower costs to maintain high server availability. These benefits come at the expense of increased bandwidth and slower, but more stable query execution times. These results substantiate the claim that lightweight interfaces can lower the cost for knowledge publishers compared to more expressive endpoints, while enabling applications to query the publishers’ data with the necessary reliability.  相似文献   

6.
QoS获益驱动的中间件调度框架研究   总被引:5,自引:0,他引:5  
张文博  陈宁江  魏峻  黄涛 《软件学报》2006,17(6):1381-1390
Web应用服务器目前普遍采用的先到先得式(FCFS)的调度框架在过载时难以保障应用的服务质量(QoS)需求.QoS获益驱动(QBD)的调度框架是一种针对这些不足而提出的请求调度解决方案.QoS获益根据应用的QoS需求得到,用于评价QoS保障对应用需求的满足情况.QBD调度框架包含了多个用于保障应用QoS需求的组件,实现了基于QoS获益的资源规划算法,能够提高服务器对应用QoS需求的保障能力.在OnceAS平台上的实验结果验证了QBD调度框架的有效性.  相似文献   

7.
Most image processing and visualization applications allow users to configure computation parameters and manipulate the resulting visualizations. SCIRun, VoIView, MeVisLab, and the Medical Interaction Toolkit (MITK) are four image processing and visualization frameworks that were built for these purposes. All frameworks are freely available and all allow the use of the ITK C++ library. In this paper, the benefits and limitations of each visualization framework are presented to aid both application developers and users in the decision of which framework may be best to use for their application. The analysis is based on more than 50 evaluation criteria, functionalities, and example applications. We report implementation times for various steps in the creation of a reference application in each of the compared frameworks. The data-flow programming frameworks, SCIRun and MeVisLab, were determined to be best for developing application prototypes, while VoIView was advantageous for nonautomatic end-user applications based on existing ITK functionalities, and MITK was preferable for automated end-user applications that might include new ITK classes specifically designed for the application  相似文献   

8.
9.
By studying the interactions between the user and a ladder or steps, with different shaped rungs, the author determines a preferred rung shape for improved ladder safety.  相似文献   

10.
11.
It has been widely reported that a large number of ERP implementations fail to meet expectations. This is indicative, firstly, of the magnitude of the problems involved in ERP systems implementation and, secondly, of the importance of the ex-ante evaluation and selection process of ERP software. This paper argues that ERP evaluation should extend its scope beyond operational improvements arising from the ERP software/product per se to the strategic impact of ERP on the competitive position of the organisation. Due to the complexity of ERP software, the intangible nature of both costs and benefits, which evolve over time, and the organisational, technological and behavioural impact of ERP, a broad perspective of the ERP systems evaluation process is needed. The evaluation has to be both quantitative and qualitative and requires an estimation of the perceived costs and benefits throughout the life-cycle of ERP systems. The paper concludes by providing a framework of the key issues involved in the selection process of ERP software and the associated costs and benefits.  相似文献   

12.
This paper reports two trials of an evaluation framework intended to evaluate novel software applications. The evaluation framework was originally developed to evaluate a risk-based software bidding model, and our first trial of using the framework was our evaluation of the bidding model. We found that the framework worked well as a validation framework but needed to be extended before it would be appropriate for evaluation. Subsequently, we compared our framework with a recently completed evaluation of a software tool undertaken as part of the Framework V CLARiFi project. In this case, we did not use the framework to guide the evaluation; we used the framework to see whether it would identify any weaknesses in the actual evaluation process. Activities recommended by the framework were not undertaken in the order suggested by the evaluation process and we found problems relating to that oversight surfaced during the tool evaluation activities. Our experiences suggest that the framework has some benefits but it also requires further practical testing.  相似文献   

13.
Software packages evaluation and selection is one of the most important activities encountered by software as a service (SaaS) users in the high performance networked computing environment, especially for the small or medium-sized enterprises. In this paper, we propose a framework for SaaS software packages evaluation and selection by combining the virtual team (VT) and the BOCR (benefits, opportunities, costs, and risks) of the analytic network process (ANP). Different from the traditional application of the BOCR model of ANP, the proposed VT-BOCR model attempts to solve the complex ANP model and overloaded pairwise comparisons by decomposing the tasks to four parts, and performed by benefits virtual team (B-VT), opportunities virtual team (O-VT), costs virtual team (C-VT), and risks virtual team (R-VT) separately. The interactive networked media on distributed environments not only makes the proposed framework possible without the limitations of time, space, and human resources, but also can take full advantage of the talent experts who are geographically dispersed. The proposed framework also shows great potentials for aiding practitioners and researchers concerned with the cloud services.  相似文献   

14.
The evolution of web technologies in the last few years has contributed to the improvement of web applications, and with the appearance of AJAX and Web 2.0 technology, a new breed of applications for the Internet has emerged: widgets, gadgets and mashups are some examples of this trend. However, as web applications become more and more complex, development costs are increasing in an exponential rate, and we believe that considering a software engineering methodology in the development process of this type of applications, contributes to the solution of this problem. In order to solve this question, this paper proposes a model-driven architecture to support web application development from the design to the implementation model. With this aim, the following tasks have been performed: first a new profile extends UML with new concepts extracted from the web domain, then a new framework supports web application development by composing heterogeneous web elements, and finally, a transformation model generates web applications from the UML extension proposed. The main contribution of this work is a cost and complexity reduction due to the incorporation of a model-driven architecture into the web application development process, but other advantages that can be mentioned are a high performance degree achieved by a prefetching cache mechanism, and a high reusability, since web elements can be reused in different web applications.  相似文献   

15.
《Information & Management》2005,42(7):947-964
The evaluation of information technology (IT) is fraught with misconception and there is a lack of understanding of appropriate IT evaluation methods and techniques. The benefits, costs and risks of IT need to be identified, managed, and controlled if businesses are to derive value from their investments. This paper presents findings from an exploratory study that used a questionnaire survey to determine the benefits, costs and risks of IT investments from 130 small-to-medium-sized enterprises (SMEs) in Australia. The analysis revealed that organizations from different industry sectors significantly differ in the amount they invest in IT but that firm size (in terms of turnover and number of employees) does not influence IT investment levels. Second, strategic benefits vary across different industry sectors. Third, the way employees adapt to change as a result of IT implementation depends on the size of the organization. Based upon the findings, a series of benchmark metrics for benefits, costs, and risks of IT are presented. It is posited that these can serve as a reference point for initiating a quality evaluation cycle in which benchmarking forms an integral component of the strategic process.  相似文献   

16.
17.
We present ONTOCOM, a method to estimate the costs of ontology engineering, as well as project management tools that support the application of the method. ONTOCOM is part of a broader framework we have developed over the five years, whose aim is to assess the business value of semantic technologies through a suite of methods, estimation models and project management tools, by which the costs and benefits of the corresponding projects are defined, measured and analyzed. The framework supports the engineering of different types of knowledge structures, including ontologies, taxonomies and folksonomies, and of information management systems leveraging such knowledge structures. It also includes benefit analysis models whose results can be used in conjunction with cost-related information in order to identify potential cost savings and to assess the feasibility of specific engineering strategies, in particular ontology reuse. The application of the methods proposed in the framework is supported by project management tools which can be used to customize these methods to a given project environment, to evaluate and validate the underlying estimations using empirical data, and to take into account their results for planning and controlling purposes.  相似文献   

18.
A framework for the evaluation of advanced control projects is illustrated in this paper by way of a case study on level control in mineral flotation. The approach taken is to investigate how improvements brought about by advanced control can be measured to a required level of statistical significance, after the controller has been commissioned. Measured improvements are translated into increases in cash flow that result from implementing an advanced controller, which is then used for project evaluation. As an introduction to the case study, a framework for establishing advanced controllers for industrial processes, which culminates in determining economic benefits, is discussed. Ways of obtaining controller benefits through the reduction of downtime and product variations, are also described. The risk of implementing an advanced control project is discussed together with typical scenarios under which such projects are often undertaken.  相似文献   

19.
Applications are increasingly being deployed in the cloud due to benefits stemming from economy of scale, scalability, flexibility and utility-based pricing model. Although most cloud-based applications have hitherto been enterprise-style, there is an emerging need for hosting real-time streaming applications in the cloud that demand both high availability and low latency. Contemporary cloud computing research has seldom focused on solutions that provide both high availability and real-time assurance to these applications in a way that also optimizes resource consumption in data centers, which is a key consideration for cloud providers. This paper makes three contributions to address this dual challenge. First, it describes an architecture for a fault-tolerant framework that can be used to automatically deploy replicas of virtual machines in data centers in a way that optimizes resources while assuring availability and responsiveness. Second, it describes the design of a pluggable framework within the fault-tolerant architecture that enables plugging in different placement algorithms for VM replica deployment. Third, it illustrates the design of a framework for real-time dissemination of resource utilization information using a real-time publish/subscribe framework, which is required by the replica selection and placement framework. Experimental results using a case study that involves a specific replica placement algorithm are presented to evaluate the effectiveness of our architecture.  相似文献   

20.
Towards runtime discovery, selection and composition of semantic services   总被引:1,自引:0,他引:1  
Service-orientation is gaining momentum in distributed software applications, mainly because it facilitates interoperability and allows application designers to abstract from underlying implementation technologies. Service composition has been acknowledged as a promising approach to create composite services that are capable of supporting service user needs, possibly by personalising the service delivery through the use of context information or user preferences. In this paper we discuss the challenges of automatic service composition, and present DynamiCoS, which is a novel framework that aims at supporting service composition on-demand and at runtime for the benefit of service end-users. We define the DynamiCoS framework based on a service composition life-cycle. Framework mechanisms are introduced to tackle each of the phases and requirements of this life-cycle. Semantic services are used in our framework to enable reasoning on the service requests issued by end-users, making it possible to automate service discovery, selection and composition. We validate our framework with a prototype that we have built in order to experiment with the mechanisms we have designed. The prototype was evaluated in a testing environment using some use case scenarios. The results of our evaluation give evidences of the feasibility of our approach to support runtime service composition. We also show the benefits of semantic-based frameworks for service composition, particularly for end-users who will be able to have more control on the service composition process.  相似文献   

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