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121.
Yanqing Ji Hao Ying John Yen Shizhuo Zhu Daniel C. Barth‐Jones Richard E. Miller R. Michael Massanari 《国际智能系统杂志》2007,22(8):827-845
Discovering unknown adverse drug reactions (ADRs) in postmarketing surveillance as early as possible is highly desirable. Nevertheless, current postmarketing surveillance methods largely rely on spontaneous reports that suffer from serious underreporting, latency, and inconsistent reporting. Thus these methods are not ideal for rapidly identifying rare ADRs. The multiagent systems paradigm is an emerging and effective approach to tackling distributed problems, especially when data sources and knowledge are geographically located in different places and coordination and collaboration are necessary for decision making. In this article, we propose an active, multiagent framework for early detection of ADRs by utilizing electronic patient data distributed across many different sources and locations. In this framework, intelligent agents assist a team of experts based on the well‐known human decision‐making model called Recognition‐Primed Decision (RPD). We generalize the RPD model to a fuzzy RPD model and utilize fuzzy logic technology to not only represent, interpret, and compute imprecise and subjective cues that are commonly encountered in the ADR problem but also to retrieve prior experiences by evaluating the extent of matching between the current situation and a past experience. We describe our preliminary multiagent system design and illustrate its potential benefits for assisting expert teams in early detection of previously unknown ADRs. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 827–845, 2007. 相似文献
122.
TM1300多媒体DSP的百兆以太网通信接口的设计实现 总被引:1,自引:0,他引:1
主要研究TM1300多媒体数字信号处理器(DSP)在pSOS嵌入式操作系统下的100 Mbit/s高速以太网接口的设计与实现.硬件方面,介绍了TM1300系统与RTL8139以太网驱动芯片通过PCI总线互连的实现方式,重点介绍了其中PCI仲裁器的设计和PCI配置空间地址的设置方法;软件方面,介绍了在DSP端内嵌的pSOS操作系统下开发软件驱动RTL8139芯片的方法,重点描述了pSOS的pNA 网络组件的NI接口、RTL8139芯片收发数据的控制方式、驱动程序的发送缓存管理、TM1300访问PCI空间的途径以及内存与数据缓存一致性等要点.最后从速率、可靠性、效率3个方面对实现的以太网通信接口进行了测试,给出了详细的实测结果.测试结果显示,与基于RTL8029芯片开发的以太网接口相比,各项性能均有较大提高. 相似文献
123.
Several types of reinforced Nb3Sn wires have been developed to prevent reduction of superconducting properties by applying a strong electromagnetic force. To fabricate a cryocooled magnet using those reinforced wires, we experimentally measured the minimum quench energy (MQE) under cryocooled conditions of some reinforced Nb3Sn wires. As a result, it became clear that thermal stability expressed as MQE was controlled by the temperature margin between the temperature of the operating condition and the transition temperature from superconductivity to normal. Using the FEM analysis, it was realized that the cause of the decline in thermal stability for the reinforced wires was the low thermal conductivity of the reinforced materials. 相似文献
124.
Yun‐Hwei Shen 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(5):581-586
A novel strategy of sweep coagulation to treat low turbidity water is presented herein. Study findings demonstrated that an Na+‐saturated bentonite with medium cation exchange capacity (CEC) resulted in significant turbidity removal at a bentonite dosage of 30 mg dm?3. Bentonite dispersion with fully delaminated platelets tended to undergo a more porous type of coagulation with intense face‐to‐face interactions of platelets and effectively entrapped TiO2 particles in band‐type structures. This type of coagulation usually results in a large volume of settled flocs with a fluffy structure and excellent turbidity removal efficiency for sweep coagulation. The sign and magnitude of electrical charge on TiO2 particles has a minor effect on the efficiency of sweep coagulation. Copyright © 2005 Society of Chemical Industry 相似文献
125.
Hung‐Yee Shu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(3):273-280
Liquid–liquid two‐phase epoxidation from cyclohexene and cyclooctene in aqueous potassium peroxymonosulfate (commercially available as Oxone®) solution was studied as an application in pollution prevention. To avoid potential emissions of volatile organic compounds an aqueous solution was employed to replace the usual chlorinated solvents used in epoxide production. A droplet column reactor and stirred tank reactor were used to investigate two‐phase synthesis of epoxide. An aqueous Oxone® solution was used to oxidize a dispersion of alkene droplets and form epoxide. The study of aqueous epoxidation in both reactors showed that the epoxidation of alkenes can be represented as a first order reaction with respect to alkene. The salting out effect of Oxone® concentration was studied in both reactors and found to be very similar at optimal conditions. In comparing the two reactors, it was found that the droplet column reactor produces larger quantities of product per unit reactor volume for the same reaction time. The objective of this study is to provide an alternative reactor design and synthesis route that can meet pollution prevention goals. Copyright © 2004 Society of Chemical Industry 相似文献
126.
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128.
MRI fuzzy segmentation of brain tissue using neighborhood attraction with neural-network optimization. 总被引:11,自引:0,他引:11
Shan Shen William Sandham Malcolm Granat Annette Sterr 《IEEE transactions on information technology in biomedicine》2005,9(3):459-467
Image segmentation is an indispensable process in the visualization of human tissues, particularly during clinical analysis of magnetic resonance (MR) images. Unfortunately, MR images always contain a significant amount of noise caused by operator performance, equipment, and the environment, which can lead to serious inaccuracies with segmentation. A robust segmentation technique based on an extension to the traditional fuzzy c-means (FCM) clustering algorithm is proposed in this paper. A neighborhood attraction, which is dependent on the relative location and features of neighboring pixels, is shown to improve the segmentation performance dramatically. The degree of attraction is optimized by a neural-network model. Simulated and real brain MR images with different noise levels are segmented to demonstrate the superiority of the proposed technique compared to other FCM-based methods. This segmentation method is a key component of an MR image-based classification system for brain tumors, currently being developed. Index Terms-Improved fuzzy c-means clustering (IFCM), magnetic resonance imaging (MRI), neighborhood attraction, segmentation. 相似文献
129.
Patricio Toro Raúl Quijada Omar Murillo Mehrdad Yazdani‐Pedram 《Polymer International》2005,54(4):730-734
The mechanical, morphological behavior and water absorption characteristics of polypropylene (PP) and silica, or PP and rice‐husk, composites have been studied. The silica used in this study as filler was a commercial type produced from soluble glass or rice husks. The compatibilizing effect of PP grafted with monomethyl itaconate (PP‐g‐MMI) and/or with vinyltriethoxysilane (PP‐g‐VTES) as polar monomers on the mechanical properties and water absorption was also investigated. In general, a high loading of the studied fillers in the polymer matrix increases the stiffness and the water absorption capacity. This effect is more noticeable in the tensile modulus of the PP/silica composite with PP‐g‐VTES as compatibilizer. However, the increase of the rice‐husk charge as a natural filler in the PP matrix decreases the stiffness, and in the presence of PP‐g‐MMI as compatibilizer in PP/rice‐husk, the tensile modulus and water absorption of the composite were improved. The better adhesion and phase continuity in the PP/silica and PP/rice‐husk composites with different compatibilizers was confirmed by the morphological study. Copyright © 2004 Society of Chemical Industry 相似文献
130.
A. Alt Dr.‐Ing. H. Mertens U. Arz L. Blessing C. Berger 《Materialwissenschaft und Werkstofftechnik》2007,38(5):402-409
High cycle fatigue of bolted connections Extensive tests regarding the influences on the fatigue of bolt‐nut‐connections of preloading with torsion, of preloading with yielding, of loading with superimposed bending and of the tested lot are processed. These influences are not yet known according to VDI 2230. New testing devices were designed for these tests, which allow a far less expensive operation and may easily be used for bolts of diameters up to M100 and testing frequencies up to 1000 Hz. The validity of fatigue resistance according to VDI 2230 is specified with respect to the test results. The determined influence of the tested lots is unexpectedly high. The manufacturing process of bolts should be improved to minimize this influence. 相似文献