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51.
矩阵方程AX-BY=Z的最小二乘中心对称解及其最佳逼近 总被引:1,自引:0,他引:1
本文研究矩阵方程AX-BY=Z的最小二乘中心对称解,给出了AX-BY=Z的最小二乘中心对称解的表达式,导出了AX-BY=Z有中心对称解的条件。讨论了在AX-BY=Z的最小二乘中心对称解集合中求与给定矩阵最佳逼近的解,并将所得结果应用于研究一类中心对称矩阵的广义特征值反问题。 相似文献
52.
对常州梳篦传统工艺产业的现状进行分析和阐述,提出以产品系统设计理念对常州梳篦产业产品企划、产品造型设计、产品制造工艺设计和产品商品化设计各部分作全面改造的构想. 相似文献
53.
基于MATLAB的模糊神经网络高压直流输电换流控制器的研究 总被引:1,自引:0,他引:1
在研究模糊逻辑控制技术、神经网络技术和高压直流输电(HVDC)系统的基础上,从原理上说明,对换流器两侧都采用模糊神经网络控制能有效地提高交流一直流(AC/DC)系统的动态特性和恒定性。整流侧和逆变侧分别提取直流线路电流、电压误差及其变化率作为模糊控制器的输入,输出作为神经网络的输入,分别控制电流和电压。用MATLAB对一典型12脉冲桥高压直流输电系统在传统控制和模糊神经控制下分别进行仿真。结果表明。与传统控制方法相比,当直流线路或者单相交流线路发生接地故障时。模糊神经控制能改善换流站直流电流和直流电压的恒定性,而且提高了交直流系统的暂态稳定性,并且双侧模糊逻辑控制要比单侧模糊逻辑控制效果好。 相似文献
54.
A multidisciplinary approach integrating method of identification of customer satisfaction needs (CSNs), the House of Quality (HoQ) chart of quality function deployment (QFD), theory of innovation problem solving (TRIZ) and fuzzy group decision-making theory for ergonomic product innovative design and evaluation in the early design stages was proposed. An integrated model and the approach procedures consists of four steps. In step 1, identification of CSNs is based on a data source triangulation approach, questionnaire survey, 5-point liner numeric rating scale, factor analysis, and Cronbach’s coefficient alpha statistic are utilized to guarantee that the CSNs are complete and reliable. In step 2, a correlation matrix is built to identify the critical ergonomic design areas and the key problems are established by analysis of the negative relationships obtained from interrelationship half-matrix at the roof of the HoQ. In step 3, to solve the problems, TRIZ main tools and contradiction analysis are utilized. Several innovative alternatives are generated by combining appropriate Inventive Principles of TRIZ, the critical ergonomic design areas and the ergonomic design principles. In step 4, a general and easy fuzzy group decision-making method for evaluating of the best design alternatives is presented. A case study of the integrated kitchen stove innovative design and evaluation is conducted to demonstrate the applicability of the proposed approach. 相似文献
55.
The effects of high hydrostatic pressure (HHP) treatment on the structural, allergenicity and functional properties of ginkgo seed protein (GSP) were investigated. GSP was treated under pressures of 100, 200, 300, 400, 500, 600 and 700 MPa. Western blotting and ELISA assay revealed that HHP treatment at pressure ranges from 300 up to 700 MPa can significantly reduce the allergenicity of GSP. Meanwhile, SDS-PAGE, MALDI-TOF-MS, CD spectra, fluorescence spectra and UV absorption spectra analysis revealed that, after HHP treatment, the GSP disintegrated into proteins with small molecular weights ranging from 4 to 30 kDa; the secondary structures of α-helices and β-sheet were largely destroyed and turned into random coil; and the UV absorption intensity, surface hydrophobicity and sulfhydryl group (SH) content of GSP were significantly increased. Moreover, the HHP-treated GSP showed markedly improved heat stability and emulsifying properties compared to the untreated GSP.Industrial relevanceAs a traditional food and medicine source, the seeds of Ginkgo biloba were used in china for several thousand years. Ginkgo seeds could be added to desserts, glazed fruit, beverages and tipple, also ginkgo seeds, as a traditional Chinese medicinal material, have been recorded in the Compendium of Materia Medical. Research shows that ginkgo seeds have a relatively high content (10%–15%) of proteins, which possess rich and reasonable composition of amino acids, and much higher content of essential amino acids than the recommended FAO/WHO standard, belonging to the high-quality protein. Ginkgo seeds proteins (GSP) have many biological activities, including anti-oxidation, anti-aging, anti-tumor, and anti-bacterial, so it has high value of nutrition and medicine. However, eating GSP could result in allergic reaction to humans, infant, or children are more sensitive to GSP, the clinical symptoms such as nausea, vomiting, bellyache, diarrhea, dysphoria, exanimation, convulsions, dyspnea, and mydriasis, and sometimes even death can occur.In the study, we used the method of high hydrostatic pressure (HHP) treatments, which can significantly improve the functional properties and reduce the antigenicity of GSP. After the HHP treatment, GSP can be transformed into proteins with small molecular weights ranging from 4 to 30 kDa, the antigenicity of GSP can be reduced by more than 95%, and the heat stability and emulsifying properties of GSP can be markedly improved. Thus, this study is very helpful for designing the hypoallergenic and improved functional GSP, which could have a relevant practical application for their use as base ingredients of food. 相似文献
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58.
Polymers with redox properties are electroactive macromolecules containing localized sites or groups that can be oxidized (loss of electrons) and reduced (gain of electrons). This review highlights trends in the chemistry, characterization and application of polymers with redox properties. In the first part, we overview the synthetic advances in the design of innovative redox polymers. Special attention is given to state-of-art techniques for the characterization of redox polymers and their important properties are also explained. The last part is devoted to the redox polymers applied in energy and medicine. First, the main redox polymers investigated in energy technologies such as batteries, supercapacitors, solar cells, biofuel cells or thermoelectric cells are reviewed. Second, the emerging applications of redox polymers in medicine technologies such as drug delivery, biosensors, actuators or smart surfaces are explained in detail. 相似文献
59.
Cao Zhifu Fei Qingguo Jiang Dong Wu Shaoqing 《Journal of Mechanical Science and Technology》2017,31(2):759-769
Journal of Mechanical Science and Technology - Substructure method has been widely applied in dynamic analysis of complex structures due to high computational efficiency. On the basis of Residual... 相似文献
60.