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71.
72.
Jiang Lei Ding Yang Xue Xialin Zhou Sensen Li Cheng Zhang Xiaoke Jiang Xiqun 《Nano Research》2018,11(11):6062-6073
Nano Research - Developing multifunctional nanoparticles to support new therapy models is a promising and challenging task to address the current dilemma on antitumor treatment. Herein, we... 相似文献
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Xue-hai Yuan Hong-xing Li E. Stanley Lee 《Computers & Mathematics with Applications》2010,59(9):3117-3129
In this paper, a new kind of intuitionistic fuzzy subgroup theory, which is different from that of Ma, Zhan and Davvaz (2008) [22], [23], is presented. First, based on the concept of cut sets on intuitionistic fuzzy sets, we establish the neighborhood relations between a fuzzy point and an intuitionistic fuzzy set . Then we give the definitions of the grades of belonging to , quasi-coincident with , belonging to and quasi-coincident with and belonging to or quasi-coincident with , respectively. Second, by applying the 3-valued Lukasiewicz implication, we give the definition of -intuitionistic fuzzy subgroups of a group for , and we show that, in 16 kinds of -intuitionistic fuzzy subgroups, the significant ones are the -intuitionistic fuzzy subgroup, the -intuitionistic fuzzy subgroup and the -intuitionistic fuzzy subgroup. We also show that is a -intuitionistic fuzzy subgroup of if and only if, for any , the cut set of is a 3-valued fuzzy subgroup of , and is a -intuitionistic fuzzy subgroup (or -intuitionistic fuzzy subgroup) of if and only if, for any (or for any ), the cut set of is a 3-valued fuzzy subgroup of . At last, we generalize the -intuitionistic fuzzy subgroup, -intuitionistic fuzzy subgroup and -intuitionistic fuzzy subgroup to intuitionistic fuzzy subgroups with thresholds, i.e., -intuitionistic fuzzy subgroups. We show that is a -intuitionistic fuzzy subgroup of if and only if, for any , the cut set of is a 3-valued fuzzy subgroup of . We also characterize the -intuitionistic fuzzy subgroup by the neighborhood relations between a fuzzy point and an intuitionistic fuzzy set . 相似文献
75.
在现有的基于傅里叶描绘子的CBIR系统中,为了提高检索速度,一般需要舍去物体轮廓经傅里叶变换后的大部分高频分量.当物体轮廓在细节部分具有较高能量时,此方法不具备有效性.为尽可能保证检索准确率并兼顾检索速度,在原有傅里叶描绘子上进行扩展,避免直接舍去高频分量,引入Fisher判别分析法将描绘子映射到子空间进行降维,并保证... 相似文献
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Fong-Ching Yuan 《Expert systems with applications》2009,36(1):829-837
A right expansion strategy can bring a company more market shares and profits, and hence increase shareholders’ equities. However, limited financial resources and various uncertainties require business practitioners to achieve their goals while controlling the risks incurred at an acceptable level. Therefore, justification of expansion investments is an important and complex topic in industry. The traditional investment analysis tools such as net present value (NPV) often tend to undervalue investment decisions. We formulate the expansion investments using real options, and develop a financial model to assess the option value. Monte Carlo simulation is considered a good way to estimate the value of the option. This valuation gives decision makers a way to choose the appropriate expansion strategy based on an integrated view of the market dynamics, but optimization is still a difficult problem to resolve. This paper presents a model of optimization under uncertainty combining system simulation with GA-based optimization to resolve the expansion problem. An industry case is used to demonstrate the application of real options to value expansion investment by using simulation–optimization. This approach also provides some new insights for the real options theory. 相似文献
78.
Ming‐Huei Chen 《Creativity & Innovation Management》2009,18(4):269-277
Personal connections, also called guanxi in Chinese culture, are embedded within a network of interdependent social exchanges, providing access to resources, information and supports, therefore facilitating performance. Building guanxi networks means building social networks. Project teams are commonly used as fundamental units in organizations, partly in order to generate more creative ideas, and so this paper evaluates how project teams use their guanxi networks within and outside of their teams and across boundaries to stimulate their creative performance. Fifty‐four product development project teams with 293 members from high‐tech Taiwanese firms participated in this study. Findings suggested that, in a guanxi culture such as Taiwan's, in order to facilitate a project team's creative performance, the most important task is to develop a more cohesive social unit before the team extends its external networks, since Chinese culture regards people first as members of groups, and secondly as individuals. 相似文献
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80.
Yuan Chen Guiping Liu Zheyi Zhang Shujuan Hou 《Structural and Multidisciplinary Optimization》2017,56(2):455-472
With the rapid development of the vehicle industry, crashworthiness has become a crucial aspect in vehicle body design. In fact, crashworthiness is a multivariable optimization design problem for a vehicle body, regardless of structure or material. However, when crashworthiness involves a large number of design variables, including both material and structure variables, it is more difficult to deal with. In this paper, an integrated design technique for materials and structures of vehicle body under crash safety consideration is suggested. First, a finite element model of the vehicle body is established according to relevant vehicle safety standards. Then, the material parameters of the vehicle body are set as analytical factors for factor screening. Next, significant factors are obtained using a three-level saturated design integrated with multi-index comprehensive balance analysis and the MaxUr (3) method, with an improved evaluation method. These screened material parameters along with the corresponding continuous variables of the structure, are considered as the design variables of the integrated design of the vehicle body. Both the weight and the crashworthiness properties are set as the design objectives. Optimal Latin hypercube sampling and radius basis functions are utilized to construct highly accurate surrogate models. Furthermore, the non-dominated sorting genetic algorithm II is implemented to seek the optimal solutions. Finally, two cases considering the roof module and the frontal module of a vehicle body are analyzed to verify the proposed method. 相似文献