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21.
This paper derives fundamental performance bounds for statistical estimation of parametric surfaces embedded in R3. Unlike conventional pixel-based image reconstruction approaches, our problem is reconstruction of the shape of binary or homogeneous objects. The fundamental uncertainty of such estimation problems can be represented by global confidenceregions, which facilitate geometric inference and optimization ofthe imaging system. Compared to our previous work on global confidence region analysis for curves [two-dimensional (2-D) shapes], computation of the probability that the entire surface estimate lies within the confidence region is more challenging because a surface estimate is an inhomogeneous random field continuously indexed by a 2-D variable. We derive an asymptotic lower bound to this probability by relating it to the exceedence probability of a higher dimensional Gaussian random field, which can, in turn, be evaluated using the tube formula due to Sun. Simulation results demonstrate the tightness of the resulting bound and the usefulness of the three-dimensional global confidence region approach.  相似文献   
22.
Post-thyroidectomy I-131 whole-body scintigraphy is an important aspect in the management of patients with thyroid cancer. The scan is used to detect residual thyroid tissue and distant functioning metastases. Extrathyroid I-131 accumulation does not always denote metastatic disease, and several potential sources of false-positive I-131 scans have been identified. This report presents four cases of benign oral disease as a cause of false-positive I-131 uptake. Benign oral disease has not been documented previously as an important source of false-positive I-131 whole-body scans.  相似文献   
23.
The atmospheric effect on the upward radiance emerging from the atmosphere above a nonuniform surface results in a reduction of the separability between the surface classes by broadening the radiance probability distribution of each class, while narrowing the total radiance range. The atmospheric modulation transfer function (MTF) is used in Fourier transform analyses to simulate the atmospheric effect on the imagery of a nonuniform surface and to demonstrate the atmospheric effect on separability of field classes.  相似文献   
24.
Mathematical decision theory can be combined with heuristic techniques to attack Artificial Intelligence problems. As a first example, the problem of breaking an image into meaningful regions is considered. Bayesian decision theory is seen to provide a mechanism for including problem dependent (semantic) information in a general system. Some results are presented which make the computation feasible. A programming system based on these ideas and its application to road scenes is described.  相似文献   
25.
Infused design. I. Theory   总被引:3,自引:3,他引:0  
The paper introduces infused design: an approach for establishing effective collaboration between designers from different engineering fields. In infused design, the design problem representation is brought up to a mathematical meta-level, which is common to all engineering disciplines. The reasoning about the problem is then done by using mathematical terminology and tools that, due to their generality, are the same for all engineers, disregarding their background. This gives engineers an opportunity to infuse their work with knowledge, methods, and solutions shared by specialists from other engineering fields. When these knowledge, methods, and solutions cross disciplinary boundaries, they are provably relevant to any problem in another domain to which it can be transformed. The suggested meta-level consists of general discrete mathematical models, called combinatorial representations (CR). Specific mathematical basis for the combinatorial representations chosen in this paper is graph theory although other representations are possible. We explain the theory of infused design and carefully contrast it with other approaches. This comparison clearly demonstrates the advantages of infused design and its potential. We conclude with several practical issues related to the introduction of infused design into practice and briefly discuss the role of information systems in infused design. A companion paper includes several examples that demonstrate the details of infused design.
Offer ShaiEmail:
  相似文献   
26.
Data for 2,069 managers from 4 regions (9 countries) taken from the International Research Groups on Management data bank and dealing with a simulation of negotiations, were contrasted with known industrial conflict patterns in the 4 regions. The importance of individual commitment to group strategy in affecting the simulation results regarding the time of negotiation and the bargaining issues was related to cultural differences. Possible implications of cultural differences to the study of managerial behavior in resolving industrial disputes are discussed. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
27.
Cranes have come to symbolize building construction itself. They perform indispensable services in moving materials and components vertically and horizontally. Used since antiquity, their history is interrelated with the development of new power sources that replaced man and mule, first steam and later internal combustion, diesel, and electric engines. Mobile cranes can be rapidly deployed to lift heavy loads. New models with telescoping booms and all-terrain travel capability, compact urban machines, and even hybrids with tower cranes are beginning to replace the familiar lattice boom truck cranes. Mobile cranes have dominated the North American market, but a cultural change appears to be taking place toward tower cranes for building projects. Tower cranes, common in Europe for decades, are globally gaining in popularity with surging real estate developments. Ideal for dense urban environments and coming with a small footprint, they are available in a growing diversity of sizes and configurations. Sophisticated electronic controls and operator assistance devices are enhancing their safe and productive operation. While cranes occupy a central role on midrise and high-rise building projects, they operate in conjunction with other types of supporting equipment that are an essential part of the overall equipment array on today’s industrialized construction sites.  相似文献   
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My method is better!   总被引:1,自引:1,他引:0  
  相似文献   
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