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双向反馈教学法在教学中的应用
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作者 汤兴林 《商情》 2011年第49期41-41,共1页
双向反馈教学法是师生双方在融洽合作的气氛中,由教师指导学生系统的、创造性的学习,应用知识和总结学习结果为目标,借以检查教学实践效果,提高教学质量的一种集讲解式、启发式、研讨式、练习式、自学式为一体的综合方法。
关键词 双向反馈教学法 设问型 猜想 比较
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Role based access control design using Triadic concept analysis 被引量:9
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作者 Ch.Aswani Kumar S.Chandra Mouliswaran +1 位作者 LI Jin-hai C.Chandrasekar 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第12期3183-3191,共9页
Role based access control is one of the widely used access control models.There are investigations in the literature that use knowledge representation mechanisms such as formal concept analysis(FCA),description logics... Role based access control is one of the widely used access control models.There are investigations in the literature that use knowledge representation mechanisms such as formal concept analysis(FCA),description logics,and Ontology for representing access control mechanism.However,while using FCA,investigations reported in the literature so far work on the logic that transforms the three dimensional access control matrix into dyadic formal contexts.This transformation is mainly to derive the formal concepts,lattice structure and implications to represent role hierarchy and constraints of RBAC.In this work,we propose a methodology that models RBAC using triadic FCA without transforming the triadic access control matrix into dyadic formal contexts.Our discussion is on two lines of inquiry.We present how triadic FCA can provide a suitable representation of RBAC policy and we demonstrate how this representation follows role hierarchy and constraints of RBAC on sample healthcare network available in the literature. 展开更多
关键词 access control concept lattice role based access control role hierarchy triadic context triadic concept analysis
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An improved adaptive response surface method for structural reliability analysis 被引量:10
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作者 刘霁 李云 《Journal of Central South University》 SCIE EI CAS 2012年第4期1148-1154,共7页
The response surface method(RSM) is one of the main approaches for analyzing reliability problems with implicit performance functions.An improved adaptive RSM based on uniform design(UD) and double weighted regression... The response surface method(RSM) is one of the main approaches for analyzing reliability problems with implicit performance functions.An improved adaptive RSM based on uniform design(UD) and double weighted regression(DWR) was presented.In the proposed method,the basic principle of the iteratively adaptive response surface method is applied.Uniform design is used to sample the fitting points.And a double weighted regression system considering the distances from the fitting points to the limit state surface and to the estimated design points is set to determine the coefficients of the response surface model.Compared with the conventional approaches,the fitting points selected by UD are more representative,and a better approximation in the key region is also observed with DWR.Numerical examples show that the proposed method has good convergent capability and computational accuracy. 展开更多
关键词 response surface structural reliability uniform design weighted regression
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Empirical Research on Mobile Phone Reading Based on User Behavior Analysis
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作者 Chen Mei Tian Shuge +1 位作者 Wang Mingyan Li Hongyan 《International English Education Research》 2015年第8期1-5,共5页
Based on the technology acceptance model (TAM) as the foundation, according to the function of mobile phone reading, the hardware design characteristics, software design characteristics, perceived entertainment, per... Based on the technology acceptance model (TAM) as the foundation, according to the function of mobile phone reading, the hardware design characteristics, software design characteristics, perceived entertainment, perceived risk and perceived price, adding them to the user behavior model, and modify the TAM model. By self-designed questionnaire, taking college students for social mobile phone reading using behavior survey, using SPSS19.0, AMOS21.0 to validate modified TAM model. The empirical results show that hardware design characteristics, software design characteristics, perceived ease of use have significant positive influence on user behavior, while perceived entertainment, perceived risk, have no significant influence on user behavior, behavior Intention has positive influence on user actual behavior. 展开更多
关键词 Mobile phone reading Technology acceptance model Behavior Intention Actual behavior
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Mega Container Ships, Pros, Cons and Its Implication Recession
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作者 Capt. Sherif Helmy Capt. Ahmed Shrabia 《Journal of Shipping and Ocean Engineering》 2016年第5期284-290,共7页
The size of container vessels has grown up in the past ten years and the trend prospect to be continued, according to analysis almost half of current ships order is for vessels exceeding 12,000 TEU's. Mega vessels ha... The size of container vessels has grown up in the past ten years and the trend prospect to be continued, according to analysis almost half of current ships order is for vessels exceeding 12,000 TEU's. Mega vessels have advantages to liners and for holding down the coast of ocean shipping but also raising concerns among vessel operation, insurance and they require for infrastructure adaptations and productivity level. Moreover further increase in ship size could result negative impacts and crises in recession. 展开更多
关键词 Pros CONS global economy.
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Bayesian Method Reliability of Flight Simulator
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作者 WANG Li XIONG Jing 《International English Education Research》 2017年第1期76-78,共3页
This paper introduces the basic viewpoints and characteristics of Bayesian statistics. Which provides a theoretical basis for solving the problem of small sample of flight simulator using Bayesian method. A series of ... This paper introduces the basic viewpoints and characteristics of Bayesian statistics. Which provides a theoretical basis for solving the problem of small sample of flight simulator using Bayesian method. A series of formulas were derived to establish the Bayesian reliability modeling and evaluation model for flight simulation equipment. The two key problems of Bayesian method were pointed out as follows: obtaining the prior distribution of WeibuU parameter, calculating the parameter a posterior distribution and parameter estimation without analytic solution, and proposing the corresponding solution scheme. 展开更多
关键词 Small sample data Flight simulation equipment Reliability modeling Bayesian method Weibull parameter
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A surrogate-based optimization algorithm for network design problems 被引量:2
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作者 Meng LI Xi LIN Xi-qun CHEN 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2017年第11期1693-1704,共12页
Network design problems (NDPs) have long been regarded as one of the most challenging problems in the field of transportation planning due to the intrinsic non-convexity of their bi-level programming form. Furthermo... Network design problems (NDPs) have long been regarded as one of the most challenging problems in the field of transportation planning due to the intrinsic non-convexity of their bi-level programming form. Furthermore, a mixture of continuous/discrete decision variables makes the mixed network design problem (MNDP) more complicated and difficult to solve. We adopt a surrogate-based optimization (SBO) framework to solve three featured categories of NDPs (continuous, discrete, and mixed-integer). We prove that the method is asymptotically completely convergent when solving continuous NDPs, guaranteeing a global optimum with probability one through an indefinitely long run. To demonstrate the practical performance of the proposed framework, numerical examples are provided to compare SBO with some existing solving algorithms and other heuristics in the literature for NDP. The results show that SBO is one of the best algorithms in terms of both accuracy and efficiency, and it is efficient for solving large-scale problems with more than 20 decision variables. The SBO approach presented in this paper is a general algorithm of solving other optimization problems in the transportation field. 展开更多
关键词 Network design problem Surrogate-based optimization Transportation planning HEURISTICS
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Hyperbolically Shaped Centrifugal Compressor
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作者 Romuald Puzyrewski Pawel Flaszy■ski 《Journal of Thermal Science》 SCIE EI CAS CSCD 2003年第3期214-218,共5页
Starting from the classical centrifugal compressor, cone shaped in meridional cross section, two modifications are considered on the basis of results from 2D and 3D flow models. The first modification is the change of... Starting from the classical centrifugal compressor, cone shaped in meridional cross section, two modifications are considered on the basis of results from 2D and 3D flow models. The first modification is the change of the meridional cross section to hyperbolically shaped channel. The second modification, proposed on the basis of 2D axisymmetric solution, concerns the shape of blading. On the strength of this solution the blades are formed as 3D shaped blades, coinciding with the recent tendency in 3D designs. Two aims were considered for the change of meridional compressor shape. The first was to remove the separation zone which appears as the flow turns from axial to radial direction. The second aim is to uniformize the flow at exit of impeller. These two goals were considered within the frame of 2D axisymmetric model. Replacing the cone shaped compressor by a hyperbolically shaped one, the separation at the corner was removed. The disc and shroud shape of the compressor was chosen in the way which satisfies the condition of most uniform flow at the compressor exit. The uniformity of exit flow from the rotor can be considered as the factor which influences the performance of the diffuser following the rotor. In the 2D model a family of stream surfaces of S1 type is given in order to find S2 surfaces which may be identified with the midblade surfaces of compressor blading. A computation of 3D type has been performed in order to establish the relations between 2D and 3D models in the calculation of flow parameters. In the presented example the 2D model appears as the inverse model which leads to 3D shape of blading whereas the 3D model has been used for the direct solution. In the presented example the confrontation of two models, 2D and 3D, leads to a better understanding of the application of these models to the design procedure. 展开更多
关键词 centrifugal compressor blading design inverse problem axisymmetrical model.
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BILEVEL PROGRAMMING MODEL AND SOLUTION METHOD FOR MIXED TRANSPORTATION NETWORK DESIGN PROBLEM 被引量:4
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作者 Haozhi ZHANG·Ziyou GAOSchool of Traffic and Transportation,Beijing Jiaotong University,Beijing 100044,China China Urban SustainableTransport Research Centre,China Academy of Transportation Sciences,Beijing 100029,China. 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2009年第3期446-459,共14页
By handling the travel cost function artfully, the authors formulate the transportation mixed network design problem (MNDP) as a mixed-integer, nonlinear bilevel programming problem, in which the lower-level problem... By handling the travel cost function artfully, the authors formulate the transportation mixed network design problem (MNDP) as a mixed-integer, nonlinear bilevel programming problem, in which the lower-level problem, comparing with that of conventional bilevel DNDP models, is not a side constrained user equilibrium assignment problem, but a standard user equilibrium assignment problem. Then, the bilevel programming model for MNDP is reformulated as a continuous version of bilevel programming problem by the continuation method. By virtue of the optimal-value function, the lower-level assignment problem can be expressed as a nonlinear equality constraint. Therefore, the bilevel programming model for MNDP can be transformed into an equivalent single-level optimization problem. By exploring the inherent nature of the MNDP, the optimal-value function for the lower- level equilibrium assignment problem is proved to be continuously differentiable and its functional value and gradient can be obtained efficiently. Thus, a continuously differentiable but still nonconvex optimization formulation of the MNDP is created, and then a locally convergent algorithm is proposed by applying penalty function method. The inner loop of solving the subproblem is mainly to implement an Ml-or-nothing assignment. Finally, a small-scale transportation network and a large-scale network are presented to verify the proposed model and algorithm. 展开更多
关键词 Bilevel programming network design optimal-value function penalty function method
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Product Family Hierarchical Associated Design and Its Hierarchical Optimization
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作者 Gang Du Jianzhong Wang 《Journal of Systems Science and Information》 2009年第3期245-252,共8页
After reviewing the literature and methodology-related issues within the field of product family design, a deficiency in the current design and development of product family is pointed out. The concept of hierarchical... After reviewing the literature and methodology-related issues within the field of product family design, a deficiency in the current design and development of product family is pointed out. The concept of hierarchical associated design is proposed in this article, according to the deficiency~ and the methods and models for realizing the notion above are described. A two-dimensional analytical model is constructed based on the composing levels and developing processes of product family. The optimization models to hierarchical associated design problems are grouped into two categories: overall-local and key-subordinate. The algorithms of the models are discussed in this paper 展开更多
关键词 product family design hierarchical optimization the two-dimensional framework
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