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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
4.
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
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
5.
S Liang Y Ohtsuki J Iwata M Furihata E Ido H Sonobe 《Canadian Metallurgical Quarterly》1996,50(5):279-283
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
6.
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.
Watabe H Hatazawa J Ishiwata K Ido T Itoh M Iwata R Takahashi T Hatano K Nakamura T 《IEEE transactions on medical imaging》1995,14(4):688-696
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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9.
We present a new theory for photogenerated carrier escape rates from single quantum wells, as a function of an applied electric field, that includes thermionic emission, direct tunneling, and tunneling via thermal occupation of upper subbands, and compare the results for GaAs/AlxGa1-xAs quantum wells with recent experiments. We account for the two dimensional (2D) density of states below the barrier, assume thermal equilibrium of carriers within the well, allow for the possibility of strain in the well and/or barrier, and include the contribution to electron thermionic emission from indirect conduction band minima. Our expressions for thermionic emission reduce, in the limit of large well width, to those derived by assuming a three-dimensional (3D) density of states. The results for electron emission from GaAs/AlxGa1-xAs quantum wells with x=0.2 and x=0.4 barriers at room temperature agree well with experiment. For wells with x=0.2 barriers, thermally assisted tunneling overtakes thermionic emission around 40 kV/cm, while for wells with x=0.4 barriers thermionic emission from the L valley conduction band minima dominates for fields less than 70 kV/cm. For holes we show that the escape rates are very sensitive to the in-plane effective masses, and results using simple expressions for the in-plane masses that do not include light/heavy-hole mixing agree poorly with experiment. The agreement with experiment is improved using in-plane masses that include light/heavy-hole mixing, particularly for wells with high barriers. We suggest that agreement with experiment would be improved by using more accurate in-plane hole masses for all of the subbands 相似文献
10.
A simple screening procedure for heterotrophic nitrifying bacteria with oxygen-tolerant denitrification activity 总被引:4,自引:0,他引:4
Matsuzaka E Nomura N Nakajima-Kambe T Okada N Nakahara T 《Journal of Bioscience and Bioengineering》2003,95(4):409-411
Various naturally occurring strains of heterotrophic nitrifying bacteria were isolated by enrichment culture using acetamide as the C and N source, and 21 strains were identified as heterotrophic nitrifiers. Using a new simple procedure, these 21 strains were also investigated for the ability to carry out denitrifcation in the presence of oxygen. Several of the nitrifying strains were found to exhibit a distinct activity that allows for denitrifcation via nitrite (NO2-) in the presence of oxygen, indicating that they have an oxygen-tolerant denitrifcation system. A wide variety of bacteria possessing both nitrification and denitrifcation capabilities in the presence of oxygen were isolated and partially characterized by using the simple screening combinatorial procedure described in this paper. 相似文献