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161.
This paper deals with design and development of a generative computer-aided process planning (CAPP) system for prismatic components and named PSG-CAPP. The proposed CAPP system has been divided into three modules. The first module is concerned with feature extraction. The second and third modules deal with planning the set-up, machine selection, cutting tool selection, cutting parameter selection, and generation of process plan sheet. The whole CAPP system is developed using Visual Basic 6.0 as front end and Oracle 7.3 as back end. The SolidWorks98 plus has been used for modelling, and feature extraction has been implemented using a program written in Visual Basic 6.0. The speciality of the developed CAPP system is that it is linked with the CAD module and it extracts the majority of features automatically prior to process planning. The developed CAPP system has been tested with aerospace components. The main feature of the proposed CAPP system is its ability to handle a variety of prismatic components and generate process plans for them. A case study has been included to highlight the potential of the CAPP system. ID="A1"Correspondance and offprint requests to: Professor P. V. Mohanram, Department of Mechanical Engineering, PSG College of Technology, Peelamedu, Coimbatore 641004, India. E-mail: msadaiah@yahoo.com  相似文献   
162.
The Journal of Supercomputing - Cloud users can acquire resources in the form of virtual machines (VMs) instances for computing. These instances can be on-demand, reserved and spot instances....  相似文献   
163.
Wireless Personal Communications - Cluster analysis is a commonly used technique by investors to create a diversified portfolio. The approach aims at maximizing returns for a tolerable degree of...  相似文献   
164.
Wireless Personal Communications - In this paper, a rack shaped two radiator element multiple input multiple output (MIMO) dielectric resonator antenna (DRA) is reported with improved axial ratio...  相似文献   
165.
Visual shape parameters and aesthetic aspects of a product are one of the crucial factors for the success of a product in the market. The type and the value of the shape parameters plays an important role in visual appearance of a product and designers tends to be critical while deciding these parameters. The aesthetic aspect of a product has been matter of concern for researchers with its electromechanical design. The Kano model has been found to be a useful tool to establish the relationship between performance criteria and customer satisfaction. To achieve the desired customer satisfaction weight of each product criteria is determined by using Kano model. This study presents an integrative design approach combining the Kano model, Taguchi method and grey relation analysis to obtain the optimal combination of shape parameters and aesthetic aspects. Prioritized criteria of aesthetic attributes have been abstracted through proposed methodology. A case study has been presented to evolve a profile of a car.  相似文献   
166.
Water Resources Management - Climate change leads to the extreme occurrence of events, water-related disasters, and pressure on existing water resources. The water resource is important for the...  相似文献   
167.
The present paper deals with flow visualization studies and the effect of tongue area on the performance of the volute casings of centrifugal machines with a swirling flow free from jets and wakes at their inlet. The flow visualization studies by wool tuft movements were conducted in the volute channel as well as in the exit diffuser and interpreted according to Moore and Kline[1]. Flow separation was observed at high inlet swirl angles near the volute tongue as well as in the exit diffuser. It was found that the volute performance was strongly dependent on the tongue area at low and high inlet swirl angles.  相似文献   
168.
Water uptake by plants is one of the major components of water balance of the vadose zone that greatly influences the contaminant and moisture movement in variably saturated soils. In this study, a nonlinear macroscopic root water uptake model that includes the impact of soil moisture stress is developed. The model incorporates the spatial and temporal variation of root density in addition to the dynamic root depth considerations. The governing moisture flow equation coupled with the water extraction by plants term is solved numerically by an implicit finite-difference method. The simulation is performed for various physical scenarios subjected to different boundary conditions. The model is tested first without considering the water uptake and results are compared with observed data available in the literature for two cases. A nonlinear water uptake term is subsequently incorporated in the model which is then simulated for corn crop for constant root depth under various characteristic moisture availability environments. Results show that the water extraction rate is closely related to the soil moisture availability in addition to the root density. The plants are observed to extract moisture mainly from the upper root dense soil profile when water content is in an optimal range, otherwise, the peak of the uptake moves to other soil layers where the moisture is easily available. Finally, the model is applied to a corn field and simulated results are validated with field data. The simulated moisture content for 2 months of crop growing season shows a reasonably good agreement with the observed data.  相似文献   
169.
Recent developments in the synthesis of prostaglandins and analogues   总被引:2,自引:0,他引:2  
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170.
Aziridines undergo ring opening smoothly with various arylamines in 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([bmim]BF4) or 1‐butyl‐3‐methylimidazolium hexafluorophosphate ([bmim]PF6) ionic liquids under mild and neutral conditions to afford the corresponding vicinal‐diamines in excellent yields with high regioselectivity. The recovered activated ionic liquids are recycled for four to five runs with no loss of activity.  相似文献   
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