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Metallurgical and Materials Transactions A - In this work, the growth of conductive AlN thin films by plasma-assisted reactive evaporation at different filament-to-substrate distances was presented... 相似文献
63.
Masoud Rabbani Fariborz Jolai Neda Manavizadeh Farzad Radmehr Babak Javadi 《The International Journal of Advanced Manufacturing Technology》2012,58(5-8):709-722
We propose a bi-objective cell formation problem with demand of products expressed in a number of probabilistic scenarios. To deal with the uncertain demand of products, a framework of two-stage stochastic programming model is presented. The proposed model considers minimizing the sum of the miscellaneous costs (machine constant cost, expected machine variable cost, cell fixed-charge cost, and expected intercell movement cost) and expected total cell loading variation. Because of conflicting objectives, we develop a two-phase fuzzy linear programming approach for solving bi-objective cell formation problem. To show the effectiveness of the proposed approach, numerical examples are solved and the results are compared with the two existing approaches in the literature. The computational results show that the proposed fuzzy method achieves lower objective functions as well as higher satisfaction degrees. 相似文献
64.
Taheri Amir Masoud Mahdavi-Nasab Homayoun 《Multimedia Tools and Applications》2018,77(23):31095-31114
Multimedia Tools and Applications - Constant increasing of visual information necessitates most efficient image compression schemes for saving storage space or reducing required transmission... 相似文献
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Hadi Zamanifard Tooran Alizadeh Caryl Bosman Eddo Coiacetto 《Journal of Urban Design》2019,24(3):340-364
This paper presents an index for measuring experiential qualities (EQs) of urban public spaces through users’ perspective. The index is underpinned by interrelated qualities of comfort, diversity and vitality, inclusiveness, and image and likeability. It is then applied to two public spaces in the Australian city of Brisbane: Queen Street Mall and South Bank Parklands. The index extends the user-centred measuring tools and can be used by practitioners, authorities and scholars to highlight users’ needs and concerns. Findings from case spaces revealed deficiencies and provided a deeper insight into EQs through integrating urban design qualities, perception and management measuring items. 相似文献
67.
Hossein Ahmadzadeh Ellips Masehian Masoud Asadpour 《Journal of Intelligent and Robotic Systems》2016,81(3-4):317-357
Employing Modular Robotic Systems (MRS) in different application domains confronts a large number of challenging problems in design, optimization, and planning, and so identifying characteristics of such problems is an important step toward finding proper solution approaches for them. In this paper, we address this issue and provide a comprehensive study on MRS through a structured survey about MRS characteristics and their applications. A novel framework called MITE is proposed to characterize both the properties and applications of MRS from four perspectives of Module, Information, Task, and Environment, based on more than 120 domain-specific features, supplemented by a mapping scheme for describing the interrelations of the four basic aspects of the Task component, namely, Application (for describing high-level tasks such as navigation and rescue), Behavior (for referring to constitutive behaviors like locomotion and manipulation which bring about Applications), Goal (for characterizing the way Behaviors are accomplished), and Operation (for designating activities specific to modular robots, such as self-reconfiguration and gait control). Also, by providing a methodical review on modular robotics, the paper deals with some analyses on recent trends, research gaps and challenges, as well as open problems in the field of MRS. 相似文献
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Mahin Baladi Movlud Valian Maryam Ghiyasiyan-Arani Masoud Salavati-Niasari 《International Journal of Hydrogen Energy》2021,46(40):21026-21039
Hydrogen storage technology is one of the most challenging issues due to the increasing demand for fossil fuel replacement and the reduction of greenhouse gas emissions. In the current paper, the main aim is one-step and eco-friendly preparation of DyFeO3-ZnO nanocomposites using Barberry fruit extract as natural precursor (with the role of both fuel and capping agent) to compare with various conventional carboxylic acids. To further examine, the effect of different parameters like calcination temperature and the type of the chelating agent was scrutinized to acquire optimum shape, structure, morphology and size of the obtained products. This is the first effort on the investigation of the hydrogen storage capacity of DyFeO3-ZnO nanocomposites in terms of role of morphology. The electrochemical hydrogen storage capacity of obtained DyFeO3-ZnO nanocomposites was studied mediated by chronopotentiometry charge-discharge methods in KOH medium. The synthesis of nanocomposites in the presence of chemical or natural capping agent (carboxylic acids or Barberry fruit extract) led to different morphologies which affects to the electrochemical performance. As a result, the electrode which is provided by plate-like DyFeO3-ZnO nanocomposites performed 600.11 mAh/g discharge capacity compared with other samples. Based on the obtained results, DyFeO3-ZnO nanocomposites can be promising compounds to improve the electrochemical performance of hydrogen storage. 相似文献
69.
Polyvinylpolypyrrolidone-supported chlorosulfonic acid has been successfully applied to perform one-pot reaction of arylaldehydes, urea, ethylacetoacetate, or cyclic 1,3-diketo compounds under solvent-free condition at 70°C to provide a series of dihydropyrimidinones and octahydroquinazolin-2,5-diones in good to excellent yields. The method offers several advantages such as high yield, short reaction time, simple workup, easy preparation, and reusability of the catalyst. The [PVPP-SO3H]+Cl? catalyst was characterized via Fourier transform infrared spectroscopy (FT-IR) and thermal gravimetric analysis (TGA). Moreover, the catalyst could be recycled several times without significant loss of its catalytic activity. Clean methodologies, easy work-up procedure, high yield, and simple preparation of the catalyst are some advantages of this article. 相似文献
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