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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   
13.
Neural networks and blood cell identification   总被引:1,自引:0,他引:1  
The objective of this project is to propose a method of identifying cells found in human blood and to classify them based upon their morphological features using neural networks. The project focuses on three major blood cell types, namely, erythrocytes, leukocytes and platelets. The data are collected using peripheral blood smears from clinical patients. The image acquisition requires 100x magnification on all the blood smears, the preprocessing involves the use of median and edge enhance filters; the feature extraction is done by performing the wavelet transform on the images. Finally classification of the blood cell types is done using ALOPEX and Back Propagation trained neural networks. The efficacy of both networks is then compared by comparing their outputs and number of iterations required to reach the final result.  相似文献   
14.
DC resistivity, dielectric constant, dielectric loss and positron annihilation spectra of (Ba1−x Ho x )TiO3 ceramics have been measured as a function of holmium concentration x. It has been found that the DC resistivity of (Ba1−x Ho x )TiO3 is strongly dependent on the Ho content: it decreases three orders of magnitude and reaches a minimum at x = 0.4%. Doping with 0.6% holmium increases the permittivity of BaTiO3 by approximately three times (from ∼1,300 to ∼4,000), with only a slight increase in the corresponding dielectric loss. The local electron density and defect concentration estimated using positron annihilation technique conforms well to the features found in the dielectric and resistivity measurements. The results have been discussed in terms of a mixed compensation model.  相似文献   
15.
Excessive power supply noise during test can cause overkill. This article discusses two models for supply noise in delay testing and their application to test compaction. The proposed noise models avoid complicated power network analysis, making them much faster than existing power noise analysis tools. can cause performance degradation and  相似文献   
16.
朱承彦 《电工技术》2007,(6):55-56,59
介绍了智能冷量积算仪的测量原理以及软硬件设计,该仪表适用于啤酒行业中冰水和乙二醇水溶液冷量计量,并得到成功应用,具有广阔的应用前景。  相似文献   
17.
东营市CNG公交汽车改装及加气站经济性研究   总被引:1,自引:0,他引:1  
对东营市公交汽车改装方案和建设相应的加气站进行了研究,结果表明,以2006年当地90号汽油、0号柴油和CNG价格计算,改装为柴油CNG双燃料公交车比柴油车,每天每车可节省燃料费92.24元,成本回收期为3.6个月;建一座年设计加气量为547.5万m^3、可供200-250辆汽车加气的常规开放式加气站,投资回收期为8年零8个月。改装汽车和建设加气站可利用当地丰富的天然气资源,节约石油,保护环境。  相似文献   
18.
以(L)-薄荷基氯为原料,通过薄荷基氯化镁分别与烯丙基溴、2-甲基-3-氯丙烯、1-溴-3-甲基-2-丁烯在Cul催化下发生偶联反应,首次合成了3-(1S,2S,5R)-薄荷基-1-丙烯,2-甲基-3-(1S,2S,5R)-薄荷基-1-丙烯和2-甲基-4-(1S,2S,5R)-薄荷基-2-丁烯,总收率分别为80.5%、83.1%和79.6%.探讨了影响反应的多种因素,找到了较好的合成条件,并用IR、 1HNMR和元素分析对产物进行了表征.  相似文献   
19.
This work pertains to output voltage stability of soft adjacent layer biased magnetoresistive heads with abutted permanent magnetic films for domain stabilization. A micromagnetic model has been developed to study the effect of the permanent magnet film microstructure and the micromagnetic properties of the abutted junction interface on head stability. The impact on head stability is analyzed with respect to interfacial ferromagnetic coupling across the junction interface and intergranular exchange coupling in the permanent magnet films among other film properties  相似文献   
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