The electromagnetic radiation characteristic of the Koch fractal dipole antenna is analyzed, the logical assumption that the current along the Koch fractal dipole antenna obeys sine distribution is demonstrated, and t...
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The electromagnetic radiation characteristic of the Koch fractal dipole antenna is analyzed, the logical assumption that the current along the Koch fractal dipole antenna obeys sine distribution is demonstrated, and the approximate expression of the magnetic vector potential of the Koch fractal dipole antenna is obtained. Using the magnetic vector potential, the far electromagnetic field is simulated, and the simulated results are compared with those obtained from the traditional symmetrical dipole antenna. For electrically large or electrically equivalent antennas, the results indicate that the electrical length of the Koch fractal dipole antenna has little influence on the radiation patterns. By using of this conclusion, the size of antennas can be reduced, as well as the least gain of antenna is satisfied. Therefore, it will be good for analytical design of multi-band and multi-functional antennas using fractal geometries. Finally, the rationalities of formulas and computations are validated by CST simulation.
Since graphene was discovered,much knowledge about its performance has been reported,but the introduction of new nanostructured materials in the industry requires a previous and intense analysis,not only of its intrin...
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Since graphene was discovered,much knowledge about its performance has been reported,but the introduction of new nanostructured materials in the industry requires a previous and intense analysis,not only of its intrinsic properties,but also of its interaction with adjacent *** interfacial effects between Graphene and other materials have been found to impoverish its
Focused on scale problems, this study demonstrated the importance of scale system selection, and necessity of scale system evaluation. The mutually exclusivity of complete consistency under different scale systems has...
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ISBN:
(纸本)9781618040169
Focused on scale problems, this study demonstrated the importance of scale system selection, and necessity of scale system evaluation. The mutually exclusivity of complete consistency under different scale systems has been proved using mathematical contradiction method, and conclusions with practical significances has been obtained through experimental method in this study that the exponential scale is more reasonable than other scales in reciprocal scale system. Although there are some errors exist in the method used by this study, there are also certain practical significances for the analysis that how to increase the accuracy of AHP method.
There are many uncertainties in multiple-attribute decision making problems so that the reliability and correctness of decision making results depend on the scientifically and reasonably confirmation of attribute weig...
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ISBN:
(纸本)9781618040169
There are many uncertainties in multiple-attribute decision making problems so that the reliability and correctness of decision making results depend on the scientifically and reasonably confirmation of attribute weights. Combination assigning method based on optimal eigenvectors which uses multi-objective optimization to integrate subjective and objective weightings was presented in the study so that the limitations of both subjective assigning method and objective assigning method have been overcome. Furthermore, decision making model based on TOPSIS method was also established to obtain more reasonable and scientific method of weightings confirmation method for multi-attribute decision making problems.
When conducting researches upon stratagem problems under the meta-synthetic integrated environment of stratagem research (SR) with the combination of qualitative and quantitative methods, we have designed comprehensiv...
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ISBN:
(纸本)9781618040169
When conducting researches upon stratagem problems under the meta-synthetic integrated environment of stratagem research (SR) with the combination of qualitative and quantitative methods, we have designed comprehensive evaluation service which takes the argumentation and evaluation procedure as its framework and establishes an analytical model for evaluation based on an evaluation index system to do data acquisition and mining among various evaluation resources, all of which helps realize the practical purpose of providing auxiliary information for quantitative decision making in the stratagem researches.
Data accessing service is designed to meet the needs of searching and utilizing various data in the meta-synthetic integrated environment of stratagem research (SR) and meanwhile data fuzzy mining engine is supposed t...
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ISBN:
(纸本)9781618040169
Data accessing service is designed to meet the needs of searching and utilizing various data in the meta-synthetic integrated environment of stratagem research (SR) and meanwhile data fuzzy mining engine is supposed to refine the collected data to make them useful for the stratagem research. Also, for accessing and utilizing database, data accessing API is designed, which provides a uniform interface for all data accessing requests and with mapping function gets all data address and accessing transparent.
Multi-project and multi-attribute decision making can be characterized as a process of overall coordination and optimization. Through the application analysis of decision making, the analysis process of decision makin...
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ISBN:
(纸本)9780889868939
Multi-project and multi-attribute decision making can be characterized as a process of overall coordination and optimization. Through the application analysis of decision making, the analysis process of decision making are projected on basis of targets, methods and evaluation;then with the combination of qualitative and quantitative methods and consideration of the features of exponential model, interval ergodic analysis method is proposed and finally established. The evaluation model to be structured on basis of the method gets multiple projects and attributes involved, and conducts ergodic calculation on condition of the given target criteria and certain region of each attribute so as to get the evaluation of the multiple projects accomplished. At last, a case study is provided in order to further elaborate the application of the analysis procedures of decision making and the interval ergodic analysis method in the multi-project and multi-attribute decision making.
A new algorithm (called CPMPSO for short), in which PSO with constraint-preserving mechanism is used as a global search algorithm and PSO itself is used as local search one, is proposed in this paper to solve mixed-va...
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Constrained optimization problems compose a large part of real-world applications. More and more attentions have gradually been paid to solve this kind of problems. An improved particle swarm optimization (IPSO) algor...
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Differential Evolution (DE) is a simple and efficient numerical optimization method. Most DE variants in the literature adopt fixed population size. This paper incorporates into DE the mechanisms of lifetime and extin...
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