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1.
The bipartite edge frustration of a graph G, denoted by φ(G), is the smallest number of edges that have to be deleted from G to obtain a bipartite spanning subgraph of G. This topological index is related to the well-known Max-cut problem, and has important applications in computing stability of fullerenes. In this paper, the bipartite edge frustration of an infinite family of fullerenes is computed. Moreover, this quantity for four classes of graphs arising from a given graph under different types of edge subdivisions is investigated.  相似文献   
2.
The circle formed in the course of surveying the movement from idea to work—which makes the act of creation—and from work to idea—which is concerned with the sphere of thinking, cognition and perception—leads to the formation of culture and civilization. Formation of any civilization is a direct result of interaction between ideas and forms. If there is no idea, there will be no form, and if there is no form, promotion of idea will be meaningless. From the ancient time, the religious-mythical idea, as a whole idea, has been leading to other ideas including philosophical, mystical and political ideas. Architecture, as a historical form, has been the outcome of interactions between the triple ideas proposed under the religious idea. In this study, an attempt is made to explain the role of each idea in the creation of architectural works of Achaemenid civilization by defining them. It also aims to review the historical form of the Achaemenid era, which was based on a philosophical-political idea, in order to investigate the role of this period in relation to architectural form which is addressed with a kind of pluralism. In other words, the main objective was to clarify the interaction between the prevailing notion of time and architectural works.  相似文献   
3.
Evolutions rooted in technology in market arena, business, and demands reforms in supply chain and consequently more demands for created value by end user are among factors causing reforms on management of supply chain. Integrity of supply chain activities and utilized technologies is an essential factor to survive competitions in the market. Organizations, therefore, need to adopt policies to coordinate themselves with new arena in market and electronic commerce. Despite bad news from Iran tail industries about unplanned production, the industry is still in growing path. In addition to easy access to mineral resources and low-energy costs, which have made it quite reasonable to invest in the industry, state tariff policies for imported tail products have made new investment chances in the industry. As a result, Iran recently won a position among five leading counties in world tail industry. However, knowing about high profit margin in tail industries, many countries have stepped into the market and through producing high-quality products have intensified competition in the market. This study tries to identify and assess IT indexes in Iran tail industry’s supply chain and hopes to take a step forward to gain better market position in international market by prioritizing the indexes using fuzzy logic.  相似文献   
4.
In this study, we report on the effects of cellulose fibres of different particle size on changes to dough water absorption and rheology; and on effects of fibre on starch and gluten, separately, at different levels of fibre incorporation (0.1–10%). Water absorption and dough‐mixing properties were affected with fibre incorporation, with 40‐μm fibre incorporation resulting in greater absorption values. Dough stickiness and extensibility were affected by cellulose fibre particle size, and decreased with increasing fibre addition. Flour or starch and fibre mixtures were evaluated using a Micro ViscoAmlyoGraph (MVAG), and the resulting gel firmness was measured using a texture analyzer. MVAG peak and final viscosities of flour samples decreased with increasing fibre content. Starch–fibre interactions followed a similar trend as flour–fibre treatments. Gluten–fibre interactions were also measured using a Gluten Peak Tester on flour–fibre and gluten–fibre mixtures. Cellulose fibre enhanced the kinetics of gluten aggregation.  相似文献   
5.
Melody Search (MS) Algorithm as an innovative improved version of Harmony Search optimization method, with a novel Alternative Improvisation Procedure (AIP) is presented in this paper. MS algorithm mimics performance processes of the group improvisation for finding the best succession of pitches within a melody. Utilizing different player memories and their interactive process, enhances the algorithm efficiency compared to the basic HS, while the possible range of variables can be varied going through the algorithm iterations. Moreover, applying the new improvisation scheme (AIP) makes algorithm more capable in optimizing shifted and rotated unimodal and multimodal problems than the basic MS.In order to demonstrate the performance of the proposed algorithm, it is successfully applied to various benchmark optimization problems. Numerical results reveal that the proposed algorithm is capable of finding better solutions when compared with well-known HS, IHS, GHS, SGHS, NGHS and basic MS algorithms. The strength of the new meta-heuristic algorithm is that the superiority of the algorithm over other compared methods increases when the dimensionality of the problem or the entire feasible range of the solution space increases.  相似文献   
6.
A low phosphorus electroless nickel coating of Ni-2.5?wt-%P alloy and a composite coating of Ni-5?wt-%P-SiC were prepared on A356 aluminium alloy substrates using two types of electroless bath solutions, an alkaline bath for low phosphorus and acidic for composite plating. The coatings morphologies have been characterised using optical and scanning electron microscopy. In addition, X-ray diffraction, microhardness, reciprocating wear testing and adhesion tests have been conducted to characterise structure and mechanical properties of the resulting coatings. The results obtained revealed that a crack-free and homogeneous coating could be produced using an optimum bath formulation. The maximum thickness of the composite coatings was 50?µm, the thickness of coatings tested. The composite coating was more resistant to wear in comparison to the low phosphorus nickel one, but had lower adhesion.  相似文献   
7.
Pure and rosemary-extract-doped hybrid nanostructure coatings have been generated using sols synthesized via acid catalyzed hydrolysis and condensation of methacryloxypropyltrimethoxysilane (TMSM) and tetraethoxysilane (TEOS) at the molar ratio of 1: 1, in combination with rosemary extract. Coatings have been deposited on stainless steel (SS) 304L substrates by spin coating followed by curing at room temperature for 24 h in air and characterized. The morphology, composition and adhesion of hybrid sol-gel coatings have been examined by SEM, EDX and pull-off test, respectively. Addition of high additive concentrations (0.1%) did not disorganize the sol-gel network. Direct pull-off test recorded a mean coating-substrate bonding strength larger than 23.21 MPa for the hybrid sol-gel coating. Corrosion testing of coatings on SS 304L was studied by potentiodynamic polarization measurements and electrochemical impedance spectroscopy after 1 h and 21 days exposure to the physiological saline solution. The corrosion resistances of hybrid rosemary-extract-doped coatings after 1 h and 21 days exposure to the physiological saline solution were higher than that of pure hybrid silica coatings, both of which had thicknesses ranging lower than 100 nm. Also the electrochemical beha-viors of doped coating were studied by potentiodynamic polarizations tests in 3.5% NaCl media and the results were shown that this system is applicable in industry.  相似文献   
8.
The authors present two optimization models for decision support tools for selecting available programs in the market. Information on reliability and cost of the available programs are considered as basic criteria for the selection. These models apply to software packages that consist of several programs where each, upon execution, performs a different function as required by the user. The objective is to maximize the average reliability of the software package, considering the tradeoff between reliability and cost of the programs. In model one, redundancy of the programs is not considered; thus, the authors select one program for each function. In model two, redundancy is considered: thus, the authors identify the optimal set of programs for each function. They begin with a discussion of the underlying concepts that rationalize the composition of the models  相似文献   
9.
Association rule mining is an active data mining research area. However, most ARM algorithms cater to a centralized environment. In contrast to previous ARM algorithms, we have developed a distributed algorithm, called optimized distributed association mining, for geographically distributed data sets. ODAM generates support counts of candidate itemsets quicker than the other DARM algorithms and reduces the size of average transactions, data sets, and message exchanges.  相似文献   
10.
The void formation and plastic deformation micromechanisms of a cold-rolled DP600 steel during tensile loading were studied by scanning electron microscopy(SEM) and electron backscatter diffraction(EBSD).The SEM observations revealed that the main void nucleation mechanism in the DP600 steel is decohesion at the ferrite-martensite interfaces.The voids were mostly observed between the closely spaced martensite islands situated at the boundaries of relatively finer ferrite grains.The EBSD results indicated a strain gradient developed from the ferrite-martensite and ferrite-ferrite interfaces into the interior of ferrite grains during the tensile deformation,which led to a stress concentration at these interfaces.Moreover,it was demonstrated that local misorientation inside the finer ferrite grains surrounded by martensite islands was higher than that for the coarser ferrite grains,which made the former more prone to void initiation.  相似文献   
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