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1.
Traffic congestion at intersections is one of the main issues to be addressed by today??s traffic management schemes. Countless efforts have been made directed toward efficiently improving the traffic situation at intersections. In this paper, we present a new traffic control strategy for an isolated intersection, in which there are no more traffic lights. Instead, vehicles embedded with In-Vehicle Information Systems communicate with the center Infrastructure to obtain their access time to the intersection. We mainly focus on the vehicle sequencing algorithms with the analysis of received information. A Branch and Bound algorithm and a heuristic are proposed to evacuate the approaching vehicles as soon as possible. Structural properties of the problem are carefully investigated to simplify the search procedure of an optimal passing sequence. Computational experiments and simulations in evacuation time, average waiting time and average queue size demonstrate the performance gain obtained when using the proposed schemes.  相似文献   

2.
The development of comprehensive picture archive and communication systems (PACS) has mainly been limited to proprietary developments by vendors, though a number of freely available software projects have addressed specific image management tasks. The openSourcePACS project aims to provide an open source, common foundation upon which not only can a basic PACS be readily implemented, but to also support the evolution of new PACS functionality through the development of novel imaging applications and services. openSourcePACS consists of four main software modules: 1) image order entry, which enables the ordering and tracking of structured image requisitions; 2) an agent-based image server framework that coordinates distributed image services including routing, image processing, and querying beyond the present digital image and communications in medicine (DICOM) capabilities; 3) an image viewer, supporting standard display and image manipulation tools, DICOM presentation states, and structured reporting; and 4) reporting and result dissemination, supplying web-based widgets for creating integrated reports. All components are implemented using Java to encourage cross-platform deployment. To demonstrate the usage of openSourcePACS, a preliminary application supporting primary care/specialist communication was developed and is described herein. Ultimately, the goal of openSourcePACS is to promote the wide-scale development and usage of PACS and imaging applications within academic and research communities.  相似文献   

3.
One of the challenges faced by an enterprise with employees in multiple locations is to design a high performance, secure and interoperable distributed computing system (DCS) to interconnect all locations and operations. The problem is computationally hard; hence, subcomponents of it have been studied in detail. These tend to be complex, predominantly theoretical, and somewhat limited from a practical standpoint in terms of providing an integrated solution. Researchers have indicated the need to study the integrated DCS design problem. We merge the complex components and demonstrate that this intrinsically hard problem can be modeled using a component-wise iterative approach. We present a methodology for resource planning and integration that is simple and practical, and can be applied to real-life problems. The methodology includes performance, cost, security and interoperability issues as DCS design objectives. It distributes data and application systems across multiple locations, and aids in security and interoperability configuration, such that the overall design objectives are satisfied. This is one of the first attempts at combining the various components of DCS design and applying it to a real-life problem. The design framework has been successfully used to design a distributed training system for a large, geographically dispersed organization  相似文献   

4.
This paper presents a distributed coevolutionary classifier (DCC) for extracting comprehensible rules in data mining. It allows different species to be evolved cooperatively and simultaneously, while the computational workload is shared among multiple computers over the Internet. Through the intercommunications among different species of rules and rule sets in a distributed manner, the concurrent processing and computational speed of the coevolutionary classifiers are enhanced. The advantage and performance of the proposed DCC are validated upon various datasets obtained from the UCI machine learning repository. It is shown that the predicting accuracy of DCC is robust and the computation time is reduced as the number of remote engines increases. Comparison results illustrate that the DCC produces good classification rules for the datasets, which are competitive as compared to existing classifiers in literature.  相似文献   

5.
李瑶  陈佳  陈罗峄 《信息技术》2013,(3):100-103
针对传统Apriori算法执行效率低的缺点,文中提出了一种适用于在海量数据中进行知识发现的改进的Apriori算法。阐述了改进的Apriori算法流程,并以某服装厂销售产生的海量销售数据为例,提出了基于改进的Apriori算法的知识发现过程。  相似文献   

6.
一种应用于射频卡的集成稳压电路的设计   总被引:1,自引:0,他引:1  
马纪丰  陈伟元  宫俊 《半导体技术》2003,28(2):48-49,57
介绍了一种应用于射频卡中稳压电路的设计方案,分析了该电路各个模块的结构和整个电路的工作过程,用HSPICE对其进行了模块仿真验证,并进行了多目标流片,测试结果达到了设计要求,表明该稳压电路可以应用于射频卡芯片中。  相似文献   

7.
Advances in digital imaging modalities as well as other diagnosis and therapeutic techniques have generated a massive amount of diverse data for clinical research. The purpose of this study is to investigate and implement a new intuitive and space-conscious visualization framework, called DBMap, to facilitate efficient multidimensional data visualization and knowledge discovery against the large-scale data warehouses of integrated image and nonimage data. The DBMap framework is built upon the TreeMap concept. TreeMap is a space constrained graphical representation of large hierarchical data sets, mapped to a matrix of rectangles, whose size and color represent interested database fields. It allows the display of a large amount of numerical and categorical information in limited real estate of the computer screen with an intuitive user interface. DBMap has been implemented and integrated into a large brain research data warehouse to support neurologic and neuroradiologic research at the University of California, San Francisco Medical Center. For imaging specialists and clinical researchers, this novel DBMap framework facilitates another way to better explore and classify the hidden knowledge embedded in medical image data warehouses.  相似文献   

8.
We propose the use of support vector machines (SVMs) for automatic hyperspectral data classification and knowledge discovery. In the first stage of the study, we use SVMs for crop classification and analyze their performance in terms of efficiency and robustness, as compared to extensively used neural and fuzzy methods. Efficiency is assessed by evaluating accuracy and statistical differences in several scenes. Robustness is analyzed in terms of: (1) suitability to working conditions when a feature selection stage is not possible and (2) performance when different levels of Gaussian noise are introduced at their inputs. In the second stage of this work, we analyze the distribution of the support vectors (SVs) and perform sensitivity analysis on the best classifier in order to analyze the significance of the input spectral bands. For classification purposes, six hyperspectral images acquired with the 128-band HyMAP spectrometer during the DAISEX-1999 campaign are used. Six crop classes were labeled for each image. A reduced set of labeled samples is used to train the models, and the entire images are used to assess their performance. Several conclusions are drawn: (1) SVMs yield better outcomes than neural networks regarding accuracy, simplicity, and robustness; (2) training neural and neurofuzzy models is unfeasible when working with high-dimensional input spaces and great amounts of training data; (3) SVMs perform similarly for different training subsets with varying input dimension, which indicates that noisy bands are successfully detected; and (4) a valuable ranking of bands through sensitivity analysis is achieved.  相似文献   

9.
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11.
ERP系统如今在各个行业已经基本实现了较为广泛的应用,但实施过程中还存在很多的问题。文章首先从ERP和知识发现技术(KDD)的时代背景与发展历程出发,结合两者的概念和相关技术及特点,分析了其部分构架和模型,对知识发现技术进行了研究,把数据仓库、知识发现和联机分析处理技术,应用到ERP中去。提出了知识发现技术在ERP上的设计方法,并在my-excel软件平台上进行了方案设计,对企业的业务流程进行了分析,实现了对ERP系统对企业管理者的决策支持。  相似文献   

12.
针对间歇性连通的移动网络环境,提出了一种新的DTN路由协议IEDR。其整合以往DTN路由算法中的设计经验,充分利用节点间相遇的机会交换数据,提高数据传达率并降低传输延迟,同时将资源开销控制在可接受的范围内。IEDR 还尝试将无线接入点作为辅助数据传播的有效途径,利用接入点间高速互联的特性为数据在广大地域内的高效传播提供便利。仿真结果表明,与一些经典路由协议相比,IEDR达到了更好的效能。  相似文献   

13.
14.
The outbreak of Severe Acute Respiratory Syndrome is the first severe and readily transmissible disease to emerge in the 21st century. Often one new infection meant tracing of several people to monitor their health conditions as well. In Singapore, several agencies coordinated their efforts to quickly bring the outbreak under control. The current breed of health-care information systems (HCIS) was not sufficient to handle new information-sharing needs during the crisis. In this paper, we take a look at the measures taken during the crisis in Singapore through a knowledge integration perspective. This perspective reveals interesting implications for HCIS.  相似文献   

15.
Medical informatics and bioinformatics: a bibliometric study.   总被引:1,自引:0,他引:1  
This paper reports on an analysis of the bioinformatics and medical informatics literature with the objective to identify upcoming trends that are shared among both research fields to derive benefits from potential collaborative initiatives for their future. Our results present the main characteristics of the two fields and show that these domains are still relatively separated.  相似文献   

16.
Li Yongliang  Xu Qiuxia 《半导体学报》2009,30(12):126001-126001-4
Wet-etch etchants and the TaN film method for dual-metal-gate integration are investigated. Both HF/HN O_3/H_2O and NH_4OH/H_2O_2 solutions can etch TaN effectively, but poor selectivity to the gate dielectric for the HF/HNO_3/H_2O solution due to HF being included in HF/HNO_3/H_2O, and the fact that TaN is difficult to etch in the NH_4OH/H_2O_2 solution at the first stage due to the thin TaO_xN_y layer on the TaN surface, mean that they are difficult to individually apply to dual-metal-gate integration. A two-step wet etching strategy using the HF/HNO_3/H_2O solution first and the NH_4OH/H_2O_2 solution later can fully remove thin TaN film with a photo-resist mask and has high selectivity to the HfSiON dielectric film underneath. High-k dielectric film surfaces are smooth after wet etching of the TaN metal gate and MOSCAPs show well-behaved C-V and J_g-V_g characteristics, which all prove that the wet etching of TaN has little impact on electrical performance and can be applied to dual-metal-gate integration technology for removing the first TaN metal gate in the PMOS region.  相似文献   

17.
李永亮  徐秋霞 《半导体学报》2009,30(12):126001-4
Wet-etch etchants and the TaN film method for dual-metal-gate integration are investigated. Both HF/HN O3/H2O and NH4OH/H2O2 solutions can etch TaN effectively, but poor selectivity to the gate dielectric for the HF/HNO3/H2O solution due to HF being included in HF/HNO3/H2O, and the fact that TaN is difficult to etch in the NH4OH/H2O2 solution at the first stage due to the thin TaOxNy layer on the TaN surface, mean that they are difficult to individually apply to dual-metal-gate integration. A two-step wet etching strategy using the HF/HNO3/H2O solution first and the NH4OH/H2O2 solution later can fully remove thin TaN film with a photo-resist mask and has high selectivity to the HfSiON dielectric film underneath. High-k dielectric film surfaces are smooth after wet etching of the TaN metal gate and MOSCAPs show well-behaved C-V and Jg-Vg characteristics, which all prove that the wet etching of TaN has little impact on electrical performance and can be applied to dual-metal-gate integration technology for removing the first TaN metal gate in the PMOS region.  相似文献   

18.
《IEEE network》2001,15(2):48-55
This article describes iSMS, a platform that integrates IP networks with the short message service in mobile telephone systems. iSMS provides a generic gateway for creating and hosting wireless data services for mobile stations. Our approach does not require any modification to the mobile telephone system architecture. The iSMS system can be quickly developed and operated by a third party or end user without involvement of mobile equipment manufacturers and telecom operators. Based on the iSMS platform, we illustrate services such as e-mail delivery/forwarding, Web access (e.g., stock and train schedule query) and handset music services. The iSMS platform and the services have been implemented for GSM networks. With iSMS, users are able to use standard GSM handsets to access wireless Internet services, while other approaches like the Wireless Application Protocol and SIM Toolkit services require function-enabled MSs  相似文献   

19.
在传统模式的虚拟导游系统中,用户只是单一的浏览信息,没有真实的互动感受.为了使虚拟导游环境更加的逼真,用户身临其境的体验,现以某校园导游系统为例,结合NPC架构模式的控制,从系统的框架设计,控制设计及实现应用等方面进行了阐述,并对该系统运行效率优化提出了解决方案.  相似文献   

20.
王坤 《信息技术》2014,(3):168-171
在传统模式的虚拟导游系统中,用户只是单一的浏览信息,没有真实的互动感受。为了使虚拟导游环境更加的逼真,用户身临其境的体验,现以某校园导游系统为例,结合NPC架构模式的控制,从系统的框架设计,控制设计及实现应用等方面进行了阐述,并对该系统运行效率优化提出了解决方案。  相似文献   

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