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1.
This paper describes a new formalism for inheritance systems, based on the formal semantics of set expressions. Using the formalism, it is possible to define new semantic classes by arbitrary set expressions operating on previously defined classes. Thus generalizing bothIS-A links andIS-NOT-A links and adding the set intersection operation. We present an efficient algorithm which follows these definitions to deduce the properties implied by the inheritance network, i.e., the properties of the classes containing a given element. The application which motivated the development of the formalism, namely semantic disambiguation of natural language, is also described.  相似文献   
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Two empirical judgment phenomena appear to contradict each other. In the revision-of-opinion literature, subjective probability (SP) judgments have been analyzed as a function of objective probability (OP) and generally have been found to be conservative, that is, to represent underconfidence. In the calibration literature, analyses of OP (operationalized as relative frequency correct) as a function of SP have led to the opposite conclusion, that judgment is generally overconfident. Reanalysis of 3 studies shows that both results can be obtained from the same set of data, depending on the method of analysis. The simultaneous effects are then generated and factors influencing them are explored by means of a model that instantiates a very general theory of how SP estimates arise from true judgments perturbed by random error. Theoretical and practical implications of the work are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Optimal control (OC) methodology is used to develop a control policy for a batch-operated solar sludge dryer with ventilation as the dominant control. Batch performance criteria and instantaneous optimization criteria are developed for two economic environments: quota limited and capital limited. The general formulation, as well as simplifications resulting from the multiplicative form of the evaporation (drying) rate model, are presented. The multiplicative form results in a single constant number, called here “control intensity,” which is used to guide the on-line control decisions. These decisions turn out to be independent of the dry solids content (DSC) of the sludge. Further simplification, by assuming a strictly constant weather, is used to demonstrate the general effects of the economic and physical (weather) environment on the solution.

The OC approach is used to address, via simulation under realistic weather conditions, several design, operation, and pricing problems. In particular, the following have been considered: sizing of the ventilation fans, determination of a fair fee for sludge disposal, finding the best final DSC, and evaluating the effect of the price of electricity. Regarding the particular location represented by the data, it has been shown that the installed capacity of the ventilation fans should be increased and that there seems to be sufficient economic incentive for solar drying.  相似文献   
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Epithelioid hemangioendothelioma is a relatively rare lesion. Although its histogenesis has been well described, its immunohistochemical characteristics remain controversial. A case of epithelioid hemangioendothelioma of the soft tissue of the right leg in a 67-year-old Chinese woman is reported. Histologic findings of intracytoplasmic lumina in the tumor cells and positive immunostaining for vimentin, factor VIII-related antigen. CD34 and Ulex europaeus agglutinin 1 (UEA-1) were obtained, demonstrating differentiation of the tumor cells to endothelial cells, although staining for antibodies to cytokeratins AE1/AE3 and CAM5.2 was weak. CD34 as well as Factor VIII-related antigen is a useful marker of endothelial differentiation in this tumor. A review of the literature is also presented.  相似文献   
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不久前,我刚好有机会参加了一个医疗论坛,会议开幕演讲吸引了我的注意,因为会议上现场示范了如何以黑客手法侵入胰岛素泵。这场会议十分具有启发性,它让我们看到了黑客如何通过无线连接,从远端入侵存在安全漏洞的医疗设备。  相似文献   
7.
We proposed a new method (;linearized method') to analyze neuroleptic ligand-receptor specific binding in a human brain using positron emission tomography (PET). We derived the linear equation to solve four rate constants, k(3), k(4), k(5), k(6) from PET data. This method does not demand a radioactivity curve in plasma as an input function to the brain, and can perform fast calculations in order to determine rate constants. We also tested the nonlinearized method including nonlinear equations which is a conventional analysis using plasma radioactivity corrected for ligand metabolites as an input function. We applied these methods to evaluate dopamine D(2) receptor specific binding of [(11)C] YM-09151-2. The value of B(max)/K(d)=k(3)/k (4) obtained by the linearized method was 5.72+/-3.1 which was consistent with the value of 5.78+/-3.4 obtained by the nonlinearized method.  相似文献   
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DNA is considered to be a promising biomolecule as a template and scaffold for arranging and organizing functional molecules on the nanoscale. The construction and evaluation of DNAs containing multiple functional molecules that are useful for optoelectronic devices and sensors has been studied. In this paper we report the efficient incorporation of perylenediimide (PDI) units into DNA by using abasic sites both as binding sites and as reactive sites and the construction of PDI stacks within the DNA structure, accomplished through the preorganization of the PDI units in the hydrophobic pocket within the DNA. Our approach could become a valuable method for construction of DNA/chromophore hybrid structures potentially useful for the design of DNA‐based devices and biosensors.  相似文献   
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In the field of the scaling-up of communication networks, numbers of communication stations (nodes) and the corresponding communication links (edges) are increasing rapidly. The reliability of the networks then becomes important. To keep the reliability of the networks, the connectivity (invulnerability) of the networks should not decrease. In this article, a method of increasing the nodes of a graph with a constant connectivity is proposed, and some examples of graph extension are shown to realize the extended networks. This work was presented in part at the 11th International Symposium on Artificial Life and Robotics, Oita, Japan, January 23–25, 2006  相似文献   
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