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61.
Journal of Mechanical Science and Technology - Determining the material deformation behavior including local strain data is very useful for analyzing the forming processes. In order to measure...  相似文献   
62.
In this research, Ni3S4–NiS with starfish morphology was synthesized with a simple hydrothermal method and then hybridized with reduced graphene oxide (rGO) as a material for high-performance supercapacitors. The crystal structure and morphology of the as-prepared materials were studied by X-ray diffraction spectroscopy and electron microscopy. Uniform distribution of Ni3S4–NiS on rGO was observed from electron microscopy images. The results showed that Ni3S4–NiS/rGO with a specific capacitance of 1578 Fg-1 and discharge time of 603 s at the current density of 0.5 Ag-1 has more capacity and stability relative to Ni3S4–NiS. The cyclic stability after 5000 cycles showed that the Ni3S4–NiS/rGO electrode is stable, and 91% of its corresponding initial capacitance retained at the end of 5000 cycles. The good results in capacitance and stability of this electrode can be regarded as an improvement for the development of highly efficient and economic supercapacitors for portable electronic devices.  相似文献   
63.
Bulletin of Engineering Geology and the Environment - The current research evaluated the effect of expansive clay stabilization using a combination of cement (0, 2, 5, 8%) with electric arc furnace...  相似文献   
64.
Analysis of a crack emanating from a circular hole in a loaded plane   总被引:1,自引:0,他引:1  
The problem of a linear elastic loaded plane containing a circular hole with an arbitrary positioned edge crack is considered. The formulation is based on consideration of the dislocational pile-up in order to represent the crack, and on a fictious dislocation in the hole in order to satisfy single valued displacement requirement for the resulting stress potentials.The results are given in terms of the stress intensity factors at the crack tip for a variety of geometries. As the results indicate, at certain geometries there exists a critical crack length such that, below that value, the crack experiences an intensive growth, and, above this value, retardation of growth or crack arrest will take place.
Résumé On considère le problème d'une plaque plane linéaire élastique, mise en charge, et comportant un trou circulaire avec une fissure de bord placée de manière arbitraire. Pour la formulation, on se base sur une représentation de la fissure par un empilement de dislocations et, pour satisfaire à l'exigence de déplacement unitaire associé aux potentiels de contrainte résultants, on suppose l'existence d'une dislocation fictive dans le trou.On présente les résultats sous forme de facteurs d'intensité de contraintes correspondant à diverses géométries. Comme l'indiquent les résultats, il existe pour certaines configurations une longueur critique de fissure telle que la fissure passe par une phase de croissance intensive lorsque sa longueur en est inférieure, ou au contraire se ralentit, voire s'arrête, lorsque sa longueur est supérieure à cette longueur critique.
  相似文献   
65.
Wireless Personal Communications - Pot experiments were conducted to study the effects of different cadmium (Cd) levels (0, 75, 150, 300 and 600 mg kg?1) on the growth,...  相似文献   
66.
Neural Computing and Applications - In this study, a new cost-oriented assembly line balancing problem is proposed and formulated. A single objective function consisting of minimizing the cost...  相似文献   
67.
A novel optimization problem of carton box manufacturing industries is introduced in this paper. A mixed integer linear formulation with multiple objective functions is developed in order to determine the value of some criteria of carton raw sheets such as size, amount, and supplier under simultaneous minimization of multiple goals such as purchasing cost of raw sheets under discount policy, wastage remained from raw sheets, and quantity of surplus of carton boxes. In order to cope with the unstable market of this sector, some parameters of the proposed formulation such as demand value of the products and price given for raw sheets are assumed to be fuzzy numbers. To tackle such fuzzy multiobjective problem, first, the fuzzy problem is converted to a crisp form using the concepts of necessity‐based chance‐constrained modelling approach. Then a new hybrid form of the fuzzy programming approach is proposed to solve the obtained crisp multiobjective problem effectively. Computational experiments on a real case given by a carton box factory show the superior result of the proposed solution approach compared with the well‐known multiobjective solution methods taken from the literature.  相似文献   
68.
Neural Computing and Applications - Reservoir water saturation is an important property of tight gas reservoirs. Improper calculation of water saturation leads to remarkable errors in following...  相似文献   
69.
Seeding is a technique used to leverage population diversity in genetic algorithms. This paper presents a quick survey of different seeding approaches, and evaluates one of the promising ones called the Seeding Genetic Algorithm. The Seeding GA does not include mutation, and it has been shown to work well on some GA-hard problems with binary representation, such as the Hierarchical If-and-Only-If or Deceptive Trap. This paper investigates the effectiveness of the Seeding GA on two problems with more complex non-binary representations: capacitated lot-sizing and single-machine scheduling. The results show, with statistical significance, that the new GA is consistently outperformed by the conventional GA, and that not including mutation is the main reason why. A detailed analysis of the results is presented and suggestions are made to enhance and improve the method.  相似文献   
70.
The scalability feature of cloud computing attracts application service providers (ASPs) to use cloud application hosting. In cloud environments, resources can be dynamically provisioned on demand for ASPs. Autonomic resource provisioning for the purpose of preventing resources over-provisioning or under-provisioning is a widely investigated topic in cloud environments. There has been proposed a lot of resource-aware and/or service-level agreement (SLA)-aware solutions to handle this problem. However, intelligence solutions such as exploring the hidden knowledge on the Web users’ behavior are more effective in cost efficiency. Most importantly, with considering cloud service diversity, solutions should be flexible and customizable to fulfill ASPs’ requirements. Therefore, lack of a flexible resource provisioning mechanism is strongly felt. In this paper, we proposed an autonomic resource provisioning mechanism with resource-aware, SLA-aware, and user behavior-aware features, which is called three-dimensional mechanism. The proposed mechanism used radial basis function neural network in order to provide providence and flexibility features. The experimental results showed that the proposed mechanism reduces the cost while guarantees the quality of service.  相似文献   
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