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排序方式: 共有988条查询结果,搜索用时 15 毫秒
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Madhab Chandra Tripathy Debasmita Mondal Karabi Biswas Siddhartha Sen 《International Journal of Circuit Theory and Applications》2015,43(6):776-792
The present work reports the realization of an analog fractional‐order phase‐locked loop (FPLL) using a fractional capacitor. The expressions for bandwidth, capture range, and lock range of the FPLL have been derived analytically and then compared with the experimental observations using LM565 IC. It has been observed that bandwidth and capture range can be extended by using FPLL. It has also been found that FPLL can provide faster response and lower phase error at the time of switching compared to its integer‐order counterpart. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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The aim of the present paper is to review the recent progress in the synthesis of in situ particle reinforced aluminum composites
using thermal, mechanical and combined mechanical-thermal activation of aluminothermic reduction reactions. The combination
of combustion synthesis (CS) and mechanosynthesis (MS) is the most recent development in the processing of advanced materials
like micro and nano aluminum based composites. The combined mechanical thermal synthesis (MTS) has widened the possibilities
for both CS and MS. MTS holds great potential for commercial viability and offers exciting processing route for the synthesis
of advanced materials. Enhanced reaction kinetics and extended concentration limits in MTS are demonstrated by illustrating
the synthesis of aluminum based nanocomposite involving Al–CeO2. 相似文献
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A three dimensional model of the BTA deep-hole machining system is presented by modelling each of the components separately and later combining to represent the total system. A model for the interaction between the workpiece and the cutting tool is also included. Such a model can determine the response of any component of the machine tool as well as the individual influence on the system performance. Based on this, physical models representing the three working methods in the BTA process can be studied, from which stochastic differential equations are derived to represent the resultant force system on the machine tool
A physical model for the stationary workpiece and rotating cutting tool working method is developed. The assumed modes method along with the Lagrange' equation is used to obtain the stochastic differential equation to represent the influence of axial force and torque, in order to obtain the response of the system under the action of the axial force and torque to predict the stability behaviour. 相似文献
A physical model for the stationary workpiece and rotating cutting tool working method is developed. The assumed modes method along with the Lagrange' equation is used to obtain the stochastic differential equation to represent the influence of axial force and torque, in order to obtain the response of the system under the action of the axial force and torque to predict the stability behaviour. 相似文献
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Amiya S. Sanyal Joydeb Mukerji Siddhartha Bandyopadhyay 《Journal of the American Ceramic Society》1991,74(9):2312-2314
Mössbauer spectra of the products obtained by carbothermal reduction and distribution of silica in the presence of iron in the temperatures range 1200o to 1540o were studied. The preponderance of β- Si3 N4 over the α form at a higher reaction temperature were assumed to be related to the formation of an Fe-Si-N liquid. The liquid did not alter its composition with the variation of reduction-temprature, Iron had no effect on the reaction mechanism below 1300o C. 相似文献
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S.K. Marik D.V.H. Rao A. Bhatnagar R.C. Pant A.C. Tikku S. Sankar 《Nuclear Engineering and Design》2006,236(7-8):730-746
Cirus, a 40 MW t, vertical tank type research reactor, having wide range of research facilities, was commissioned in the year 1960. This research reactor, situated at Mumbai, India has been operated and utilized extensively for isotope production, material testing and neutron beam research for nearly four decades. With a view to assess the residual life of the reactor, detailed ageing studies were carried out during the early 1990s. Based on these studies, refurbishment of Cirus for its life extension was taken up. During refurbishment, additional safety features were incorporated in various systems to qualify them for the current safety standards. This paper gives the details of the operating experiences, utilization of the reactor along with methodologies followed for carrying out detailed ageing studies, refurbishment and safety upgradation for its life extension. 相似文献
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Recursive algorithms for implementing digital image filters 总被引:1,自引:0,他引:1
Ferrari LA Sankar PV Shinnaka S Sklansky J 《IEEE transactions on pattern analysis and machine intelligence》1987,(3):461-466
The B-spline functions are used to develop recursive algorithms for the efficient implementation of two-dimensional linear digital image filters. These filters may be spatially varying. The B-splines are used in a representation of the desired point spread function. We show that this leads to recursive algorithms and hardware implementations which are more efficient than either direct spatial domain filter realizations or FFT implementations. The Z-transform is used to develop a discrete version of Duhamel's theorem. A computer architecture for B-spline image filters is proposed and a complexity analysis and comparison to other approaches is provided. 相似文献
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The article investigates an integrated multi-layer supply chain model consisting of supplier, manufacturer and retailer while supply disruption, machine breakdown, safety stock, maintenance breakdown occur simultaneously. At beginning of the production, manufacturer keeps some raw materials in stock received from second supplier at high price, as safety stock due to supply disruption of first supplier. Corrective maintenance is done immediately to restore its normal stage when machine breakdown occurs. Stock out situations at manufacturer and retailer are considered due to disruption of production for machine breakdown. The integrated expected costs of the chain in centralized (collaborating) and decentralized (Stakelberg approach) system are compared. A numerical example and its sensitivity analysis are provided to test feasibility of the model. 相似文献