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911.
为了满足地市级移动通信的业务需求,通过对逻辑数据集市和物理数据集市的分析,确定了数据集市的设计思路,构建了数据集市的结构,并设计出数据集市的主题模块。测试表明,其功能模块和增值业务达到了预期效果。 相似文献
912.
电网运营管理对保障电力供应和服务十分重要,电网运营要求较高的效率和可靠性。文章介绍了电网企业移动现场作业信息平台,阐述了其建设目标和技术架构,提出整体解决方案,规范了现场作业流程,实现作业现场与后台信息的实时传递,提高作业效率。该平台可以提升电网管理水平,具有广泛的应用和推广价值。 相似文献
913.
以目前在国外广泛应用的Drupal 7为应用开发框架,结合HTML5、样式表、动态脚本和第三方插件技术,通过在WAMP平台上对Drupal进行二次开发,设计了一套具有友好界面、易添加与删除容器,并动态加载数据的布局模板.该模板采取分层设计,从根容器到目标内容容器构建页面框架;采用HTML5自适应布局设计方法,针对不同的业务需求完成个性化定制界面UI.同时介绍了利用主流浏览器调试工具对界面代码进行分析与调试. 相似文献
914.
This paper discusses the numerical modeling of steam plasma in a DC non-transferred torch equipped with well-type cathode, where the non-trivial azimuthal velocity component and turbulent effect are both taken into account. In order to investigate the complicated flow characteristics of thermal plasma due to the interaction between steam and electric arc, the flow filed inside the plasma torch is modeled by the magnetic–hydrodynamic (MHD) equations. The governing equations are then solved numerically using a non-staggered finite volume discretization based on Cartesian grid system. The anode location and maximum current density at cathode are fixed by the corresponding experimental measurement at a given flow rate. The predicted result suggests that the steam plasma can be accelerated to a mean velocity of 1500 m/s at torch outlet with the mass flow rate of 5 g/s and the system current of 180 A. A strong vortex flow structure is found inside the torch due to the introduction of azimuthal velocity at the gas inlet, which should help to stabilize the rotating arc during the torch operation. 相似文献
915.
916.
This paper aims to reduce the problems of incomplete data in computed tomography, which happens frequently in medical image process and analysis, e.g., when the high-density region of objects can only be penetrated by X-rays at a limited angular range. As the projection data are available only in an angular range, the incomplete data problem can be attributed to the limited angle problem, which is an ill-posed inverse problem. Image reconstruction based on total variation (TV) reduces the problem and gives better performance on edge-preserving reconstruction; however, the artificial parameter can only be determined through considerable experimentation. In this paper, an effective TV objective function is proposed to reduce the inverse problem in the limited angle tomography. This novel objective function provides a robust and effective reconstruction without any artificial parameter in the iterative processes, using the TV as a multiplicative constraint. The results demonstrate that this reconstruction strategy outperforms some previous ones. 相似文献
917.
Haiping Lu Author Vitae Konstantinos N. Plataniotis Author Vitae Author Vitae 《Pattern recognition》2011,44(7):1540-1551
Increasingly large amount of multidimensional data are being generated on a daily basis in many applications. This leads to a strong demand for learning algorithms to extract useful information from these massive data. This paper surveys the field of multilinear subspace learning (MSL) for dimensionality reduction of multidimensional data directly from their tensorial representations. It discusses the central issues of MSL, including establishing the foundations of the field via multilinear projections, formulating a unifying MSL framework for systematic treatment of the problem, examining the algorithmic aspects of typical MSL solutions, and categorizing both unsupervised and supervised MSL algorithms into taxonomies. Lastly, the paper summarizes a wide range of MSL applications and concludes with perspectives on future research directions. 相似文献
918.
Hao WangAuthor VitaeJens B. SchmittAuthor Vitae Ivan MartinovicAuthor Vitae 《Performance Evaluation》2011,68(2):201-219
During the last two decades, starting with the seminal work by Cruz, network calculus has evolved as a new theory for the performance analysis of networked systems. In contrast to classical queueing theory, it deals with performance bounds instead of average values and thus has been the theoretical basis of quality of service proposals such as the IETF’s Integrated and Differentiated Services architectures. Besides these it has, however, recently seen many other application scenarios as, for example, wireless sensor networks, switched Ethernets, avionic networks, Systems-on-Chip, or even to speed-up simulations, to name a few.In this article, we extend network calculus by adding a new versatile modeling element: a demultiplexer. Conventionally, demultiplexing has been either neglected or assumed to be static, i.e., fixed at the setup time of a network. This is restrictive for many potential applications of network calculus. For example, a load balancing based on current link loads in a network could not be modeled with conventional network calculus means. Our demultiplexing element is based on stochastic scaling. Stochastic scaling allows one to put probabilistic bounds on how a flow is split inside the network. Fundamental results on network calculus with stochastic scaling are therefore derived in this work. We illustrate the benefits of the demultiplexer in a sample application of uncertain load balancing. 相似文献
919.
The design and development of suspended handles for reducing hand-arm vibration in petrol driven grass trimmer 总被引:1,自引:0,他引:1
Ying Hao KoOoi Lu Ean Zaidi Mohd Ripin 《International Journal of Industrial Ergonomics》2011,41(5):459-470
The portable petrol driven grass trimmer is identified as a type of machine whose operator can be subjected to large magnitude of hand-arm vibration. These vibrations can cause complex vascular, neurological and musculoskeletal disorder, collectively named as hand-arm vibration syndrome. The vibration total level on the handle of grass trimmer of 11.30 m/s2 was measured, and it has reached the exposure limit value of 5.0 m/s2 for daily vibration exposure A(8). New suspended handles were designed to reduce the vibration level. Three different prototype handles with rubber mounts were designed. Handles were made of different materials, and the distance of rubber mounts were varied. From the study, it was observed that not all the handles with rubber mounts were effective in reducing hand-arm vibration. The reduction of vibration depended on the handle material and distance installed between rubber mount and vibration transmissibility of handle-isolation system. Subjective ratings of perception of vibration were measured, and the results indicated that operators were not fully aware of the level of vibration. A prototype handle that is made of heavier material results in the lowest hand-arm vibration of 2.69 m/s2. The new handle has significantly reduced the vibration total value by 76% compare with the existing commercial handle.
Relevance to industry
Large numbers of workers are employed to perform grass trimming job in many developing countries. This paper presents the effect of handle types (commercial and prototype) on the commonly used grass trimmer. 相似文献920.
This paper addresses a very important question—how to select the right products to promote in order to maximize promotional
benefit. We set up a framework to incorporate promotion decisions into the data-mining process, formulate the profit maximization
problem as an optimization problem, and propose a heuristic search solution to discover the right products to promote. Moreover,
we are able to get access to real supermarket data and apply our solution to help achieve higher profits. Our experimental
results on both synthetic data and real supermarket data demonstrate that our framework and method are highly effective and
can potentially bring huge profit gains to a marketing campaign. 相似文献