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This paper introduces and evaluates a new class of knowledge model, the recursive Bayesian multinet (RBMN), which encodes the joint probability distribution of a given database. RBMNs extend Bayesian networks (BNs) as well as partitional clustering systems. Briefly, a RBMN is a decision tree with component BNs at the leaves. A RBMN is learnt using a greedy, heuristic approach akin to that used by many supervised decision tree learners, but where BNs are learnt at leaves using constructive induction. A key idea is to treat expected data as real data. This allows us to complete the database and to take advantage of a closed form for the marginal likelihood of the expected complete data that factorizes into separate marginal likelihoods for each family (a node and its parents). Our approach is evaluated on synthetic and real-world databases. 相似文献
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An experimental study of the effects produced by different parameters of the heat-quenching cycle permitted the optimization of the properties typical of these martensitic stainless steels: hardness and corrosion resistance. The results obtained demonstrate that the heating temperatures currently used in industrial quenching treatment of these steels should be modified. 相似文献
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BACKGROUND: Arteriovenous malformations (AVMs) are an abnormal communication between arterial and venous structures. Pelvic AVMs have been infrequently described in the literature and represent an uncommon cause of a palpable pelvic mass. CASE: A case of pelvic AVM with ureteral obstruction occurred. The location and radiologic appearance of the AVM suggested a complex adnexal mass. During exploration and resection of the mass, significant bleeding was encountered. The diagnosis of AVM was made only retrospectively, with histologic examination of the specimen. CONCLUSION: AVMs are an uncommon and unique cause of pelvic pathology. Preoperative diagnosis will alert the surgeon as to the technically difficult resection that may be encountered and to the massive bleeding that can be associated with their removal. 相似文献
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Traditionally, companies used to view themselves as separate entities and did not devote efforts to collaborate with other echelons of the extended enterprise. This even happened at multi-site companies owning different plants that belonged to the same supply chain. However, manufacturing facilities of the same supply chain should intensively share information and coordinate planning and scheduling tasks in order to get a globally optimized solution. This paper discusses some specific characteristics of the planning and scheduling problem in the extended enterprise including an analysis of a case study, and reviews the available state-of-the-art research studies in this field. Most studies suggest that integrated approaches can have a significant impact on the system performance, in terms of lower production costs, and less inventory levels. The paper provides some conclusions and suggestions of future works. 相似文献
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BE Gilbert C Knight FG Alvarez C Waldrep JR Rodarte V Knight WL Eschenbacher 《Canadian Metallurgical Quarterly》1997,156(6):1789-1793
Cyclosporine A (CsA) in liposomes of dilauroylphosphatidylcholine (DLPC), containing 118 micrograms of CsA/L of aerosol with a particle size of 1.6 to 1.7 micron diameter, was inhaled by 10 nonsmoking, normal volunteers each for 45 min. Aerosol was administered through an Aerotech II nebulizer (CIS-US, Inc., Bedford, MA) mouthpiece. Eight of the 10 volunteers had tracheal irritation and intermittent coughing following exposure. FEV1 and FVC values were mildly reduced, but returned to normal in 1 h. Blood chemical and hematologic values were unchanged at any time point after as opposed to before inhalation. Nine of the 10 volunteers later inhaled DLPC only, administered through the nebulizer mouthpiece. There was no change in FEV1 or FVC values, and there was no coughing or tracheal irritation. Subsequently, five of the volunteers who had previously had respiratory reactions inhaled CsA-DLPC liposome aerosol for 45-min, but through a mouth-only face mask. There was no tracheal irritation, coughing, or changes in spirometric measures. Blood concentrations of CsA at 15 min after the 45-min inhalation with a face mask averaged 83 +/- 42 ng/ml (mean +/- SD). At 24 h after treatment, CsA was undetectable in blood of the initial 10 volunteers. These studies indicate that CsA-DLPC liposome aerosol can be safely explored as a treatment for patients with moderately severe asthma. 相似文献
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Pedro Jacobi 《突发事故与危机管理杂志》1997,5(3):131-139
This article describes and analyzes the main environmental problems that affect the city of Sao Paulo. The article views the impacts of the local dynamics of urbanization and its effects on daily life. The discussion is centered on the complexity of the environmental management processes and the implementation of conventional and non-conventional policies and programmes to prevent environmental degradation. Possible solutions to alleviate the effects of floods and climate factors on households are debated as well as the possibilities of formulating more participatory oriented policies to engage citizens in the knowledge of environmental risks. These issues represent a very complex challenge to the urban government of Sao Paulo. 相似文献