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11.
A computer program for calculating the Mie scattering of electromagnetic radiation by a sphere is described. The program will evaluate, amongst other parameters, the Mie scattering functions am and bm, the extinction, scattering, back-scattering, absorption and radiation pressure efficiencies, the intensity functions, I1 and I2 and the polarisation ratios . The program can be made available to other users and computations can be commissioned on a repayment basis. A library of results is being established.  相似文献   
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In the global market place, many companies have had to adapt their strategies to meet significant challenges. A strategy adopted by some companies has been international expansion via acquisitions. The need for expert knowledge to determine an appropriate company to acquire has been complicated by the sheer size of the global market place. The costs associated with this in relation to time and personnel have created the need for a computerised expert system to be developed. This paper endeavours to show how a proposed fuzzy based system can assist in the identification of a company for acquisition. The authors discuss the manipulation of the magnitude of fuzzy membership functions to communicate priorities within the system. The fuzzy system is designed to assist financial experts in identifying a suitable company for acquisition in the corporate acquisition process. This includes the deliberate weighting of certain inputs and results above others in the decision-making process. The system attempts to learn and simulate the human precedence given to particular financial statistics in company analysis. The system uses the magnitude of the fuzzy membership functions to reflect the human precedence given to each financial ratio. This enables a particular company's strengths and weakness to be considered while concurrently considering their significance and relevance to the acquiring organisation. The system will enable a larger number of companies to be analysed in a more time and cost-effective manner. The development of this system is intended to illustrate that a fuzzy system can aid the financial experts of an acquiring organisation in the global acquisition process.  相似文献   
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Pattern selection methods have been traditionally developed with a dependency on a specific classifier. In contrast, this paper presents a method that selects critical patterns deemed to carry essential information applicable to train those types of classifiers which require spatial information of the training data set. Critical patterns include those edge patterns that define the boundary and those border patterns that separate classes. The proposed method selects patterns from a new perspective, primarily based on their location in input space. It determines class edge patterns with the assistance of the approximated tangent hyperplane of a class surface. It also identifies border patterns between classes using local probability. The proposed method is evaluated on benchmark problems using popular classifiers, including multilayer perceptrons, radial basis functions, support vector machines, and nearest neighbors. The proposed approach is also compared with four state-of-the-art approaches and it is shown to provide similar but more consistent accuracy from a reduced data set. Experimental results demonstrate that it selects patterns sufficient to represent class boundary and to preserve the decision surface.  相似文献   
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GY Han  GQ Shi  LT Qu  JY Yuan  FE Chen  PY Wu 《Polymer International》2004,53(10):1554-1560
N‐Substituted pyrrole derivatives with chiral side groups have been synthesized and electrochemically polymerized in acetonitrile containing tetrabutylammonium perchlorate (TBAClO4) and (S)‐(+)‐camphor‐10‐sulfonic acid ((S)‐(+)‐CSA) or (R)‐(?)‐camphor‐10‐sulfonic acid ((R)‐(?)‐CSA). The resulting N‐substituted polypyrrole films were characterized by cyclic voltammetry, infrared, Raman and X‐ray photoelectron (XPS) spectroscopies. XPS results demonstrated that the as‐grown polymer films are preferably doped by CSA anions when the monomer and the CSA anion have the same optical rotation dispersion (ORD). Furthermore, the conductivities of the polymers synthesized in the media containing CSA with the same ORD of the corresponding monomers were measured to be about 2–10 times higher than those of polymers obtained from electrolytes without CSA. Copyright © 2004 Society of Chemical Industry  相似文献   
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The effects of the indolehallucinogen psilocybin, a mixed 5-HT2 and 5-HT1 agonist, on regional cerebral glucose metabolism were investigated in 10 healthy volunteers with PET and [F-18]-fluorodeoxyglucose (FDG) prior to and following a 15- or 20-mg dose of psilocybin. Psychotomimetic doses of psilocybin were found to produce a global increase in cerebral metabolic rate of glucose (CMRglu) with significant and most marked increases in the frontomedial and frontolateral cortex (24.3%), anterior cingulate (24.9%), and temporomedial cortex (25.3%). Somewhat smaller increases of CMRglu were found in the basal ganglia (18.5%), and the smallest increases were found in the sensorimotor (14.7%) and occipital cortex (14.4%). The increases of CMRglu in the prefrontal cortex, anterior cingulate, temporomedial cortex, and putamen correlated positively with psychotic symptom formation, in particular with hallucinatory ego disintegration. The present data suggest that excessive 5-HT2 receptor activation results in a hyperfrontal metablic pattern that parallels comparable metabolic findings associated with acute psychotic episodes in chronic schizophrenics and contrasts with the hypofrontality in chronic schizophrenic patients.  相似文献   
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This paper presents a number of case histories illustrating the benefits and costs of certain types of engineering measurement and testing, with a focus on strain‐gauged land‐based structures. The benefits are described mainly in terms of safety, economy and environment. The costs are related to the amount of data collected and processed. The paper concludes with some technical and financial guidance for clients, owners, consultants and contractors who may be considering these types of activities.  相似文献   
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