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91.
92.
Hiroyuki Sato Hernán Aguirre Kiyoshi Tanaka 《Annals of Mathematics and Artificial Intelligence》2013,68(4):197-224
In this work, we analyze variable space diversity of Pareto optimal solutions (POS) and study the effectiveness of crossover and mutation operators in evolutionary many-objective optimization. First we examine the diversity of variables in the true POS on many-objective 0/1 knapsack problems with up to 20 items (bits), showing that variables in POS become noticeably diverse as we increase the number of objectives. We also verify the effectiveness of conventional two-point and uniform crossovers, Local Recombination that selects mating parents based on proximity in objective space, and two-point and uniform crossover operators which Controls the maximum number of Crossed Genes (CCG). We use NSGA-II, SPEA2, IBEA ??+? and MSOPS, which adopt different selection methods, and many-objective 0/1 knapsack problems with $n=\{100,250,500,750,\mbox{1,000}\}$ items (bits) and m?=?{2,4,6,8,10} objectives to verify the search performance of each crossover operator. Simulation results reveal that Local Recombination and CCG operators significantly improve search performance especially for NSGA-II and MSOPS, which have high diversity of genes in the population. Also, results show that CCG operators achieve higher search performance than Local Recombination for m?≥?4 objectives and that their effectiveness becomes larger as the number of objectives m increases. In addition, the contribution of CCG and mutation operators for the solutions search is analyzed and discussed. 相似文献
93.
Robust control method for the inverted pendulum system with structured uncertainty caused by measurement error 总被引:1,自引:1,他引:0
In this article, we propose a design method for an inverted pendulum system with a structured uncertainty. We consider that
such an uncertainty is caused by a measurement error in the rotation angle of the pendulum and effects on the system structure
that cannot be included in the nominal elements. For the uncertain system obtained, we apply an integral tracking control
and the guaranteed cost control to design a robust, stable, tracking control system. Finally, we show the effectiveness of
our method through a numerical example. 相似文献
94.
Adaptation is a fundamental property of human perception. Recently, it was found that there are two opposite types of adaptation to repetitive stimuli with a temporal difference. In this article, we construct an integrative model of adaptation. We model the perception as a Bayesian inference, and represent the two types of adaptation as changes in the likelihood function and the prior distribution in the Bayesian inference. We examine our model analytically and show how the types of adaptation depend on model parameters. 相似文献
95.
Kaneko K Inoke K Sato K Kitawaki K Higashida H Arslan I Midgley PA 《Ultramicroscopy》2008,108(3):210-220
The growth mechanism and morphology of Ge precipitates in an Al-Ge alloy was characterized by a combination of in-situ transmission electron microscopy, high-resolution transmission electron microscopy and three-dimensional electron tomography. Anisotropic growth of rod-shaped Ge precipitates was observed by in-situ transmission electron microscopy over different time periods, and faceting of the precipitates was clearly seen using high-resolution transmission electron microscopy and three-dimensional electron tomography. This anisotropic growth of rod-shaped Ge precipitates was enhanced by vacancy concentration as proposed previously, but also by surface diffusion as observed during the in-situ experiment. Furthermore, a variety of precipitate morphologies was identified by three-dimensional electron tomography. 相似文献
96.
S Nakajima N Shuke T Aburano S Ishikawa J Sato I Sakata T Takemura 《Canadian Metallurgical Quarterly》1994,31(11):1379-1383
We synthesized four new tumor imaging agents, 99mTc-labeled metalloporphyrins (99mTc-STA-R12, -STA-R21, -STA-RN101 and -ATN-12) for the tumor imaging. We compared the differences of tumor imaging potency among these agents in CDF1 mice implanted with colon 26 tumor. Tumor images with these agents were obtained by using digital gamma-camera (RC135-E, Hitachi, Tokyo) and the biodistributions were analyzed by computerized medical radionuclide imageanalyser (RP-200, Hitachi, Tokyo). The highest tumor organ ratio and the excellent tumor image were obtained by 99mTc-STA-R12 (13,17-Bispropanyl aspartic acid-3-ethenyl-8-[N,N',N",N"-tetrakis (carboxylmethyl-2,7,12,18-tetramethyl-porphyrinato]-manga nes e(III). The maximum concentration of 99mTc-STA-R12 in tumor tissue was observed at around 120 minutes after i.v. injection. On the contrary, the uptake rates of other organs and tissues such as liver, brain, muscle, lung, bone and blood continuously decreased. The rapid accumulation of STA-R12 in cancer tissue and the clearance from other tissue suggested a potential usefulness of this compound for tumor imaging agent. 相似文献
97.
We experimentally found the unexpected phenomena of scattering in laminated polarization splitters (LPS's) composed of a-Si:H-SiO(2) multilayer and studied its mechanism. The scattering phenomena strongly depend on the incident angle and polarization of the incident light. To reduce the scattering loss in LPS's, a multilayer with flat layer boundaries is fabricated with rf bias sputtering. As a result, the insertion loss of the LPS is reduced to ~ 1 × 10(-3) dB/ μm, which is acceptable for practical uses. 相似文献
98.
M. Nakao Y. Hatamura T. Sato K. Koyano K. Ichiki H. Sangu M. Hatakeyama T. Kobata K. Nagai 《Microsystem Technologies》1995,1(3):124-128
In order to make micro 3-D structures, we are designing a table-sized factory, namely Nano Manufacturing World (NMW). In NMW, we challenged to use a new process fused by semiconductor process for preciseness and machine process for 3-dimensionality. In order to realize the new process, we designed three new mechanisms in this paper: multi-face shape making beam, co-focus rotational robot and micro mechanical tools. Through an evaluation to actually make a micro Gojunoto with the mechanisms, we confirmed their validities for functions of integration of 3-D shape construction and assembly. 相似文献
99.
A data-driven design method for a cascade control system is proposed. The cascade control system consists of inner and outer loops, where the control interval of the outer loop is an integer multiple of the inner loop; hence, the system is a dual-rate system. In the proposed method, controllers in the inner and outer loops are designed based on one-shot data. In such a dual-rate cascade system, since the controllers are designed using different data-rate signals, the lifting technique is applied to align the dual-rate data. To show its effectiveness, the proposed method is compared with a conventional single-rate cascade control method, and numerical simulations and experiments are presented to examine servo and regulation performance. 相似文献
100.
AIM: To introduce the "starlight" test which was devised to check binocular vision in normal conditions of seeing in a rapid, easy, and cost effective manner and to estimate the possibility of its clinical use in screening the binocular visual field of patients. METHOD: The Bagolini striated glass test consists of optically plano lenses with imperceptible parallel scratches that barely blur the environment but produce two perpendicular luminous stripes (right eye stripe of 45 degrees and left eye stripe of 135 degrees) when subjects with normal binocular vision view one light source. Unlike the original Bagolini test, the starlight test uses three light sources in horizontal or vertical lines according to the testing purposes and the subject is asked to fixate upon the centre light. Through Bagolini glasses, the subject observes the resulting grid-like pattern and the state of binocular visual field of the subject can be roughly estimated. RESULTS: Normal subjects and patients with strabismus, visual field loss from intracranial diseases, glaucoma, retinitis pigmentosa, and functional visual loss were examined using the starlight test and findings from each case were discussed. CONCLUSIONS: The starlight test, which was made by hand at a low cost, is a simple test that can be used clinically. It provides information about the state of binocular vision of patients in normal conditions of seeing. It is also useful because it enables the examiner to share similar experiences with the examinee. The results suggest it can be effective in visual field screening. 相似文献