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排序方式: 共有998条查询结果,搜索用时 109 毫秒
911.
Ashok Kumar Goel Suresh C. Saxena Surekha Bhanot 《International journal of systems science》2013,44(10):709-722
This paper deals with a fast and computationally simple Successive Over-relaxation Resilient Backpropagation (SORRPROP) learning algorithm which has been developed by modifying the Resilient Backpropagation (RPROP) algorithm. It uses latest computed values of weights between the hidden and output layers to update remaining weights. The modification does not add any extra computation in RPROP algorithm and maintains its computational simplicity. Classification and regression simulations examples have been used to compare the performance. From the test results for the examples undertaken it is concluded that SORRPROP has small convergence times and better performance in comparison to other first-order learning algorithms. 相似文献
912.
Sumita Shekhawat Pratibha Sekra V. K. Saxena J. S. Saini D. Bhatnagar 《国际射频与微波计算机辅助工程杂志》2011,21(4):407-412
A novel dual‐frequency broadband design of a single‐layer single‐feed circular microstrip antenna with an off‐centered Y‐slot is demonstrated in this communication. By selecting a suitable location of the Y‐slot in the circle, the proposed antenna on glass epoxy FR‐4 substrate not only resonates efficiently at two closely spaced frequencies (2.736 and 2.868 GHz) but also offers improved bandwidth (210 MHz or 7.5%) in comparison with a conventional circular microstrip patch antenna (~2%). From the measured results, almost identical broadside radiation patterns are obtained at two resonant frequencies, and the variation of less than 1 dBi in gain values is achieved in the frequency range where broadband behavior is observed. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011. 相似文献
913.
Lokesh Kumar Saxena P. K. Jain 《The International Journal of Advanced Manufacturing Technology》2012,62(1-4):385-404
In a global dynamic environment, there is a need to develop organizations and facilities significantly more flexible and responsive. This work proposes an integrated model of dynamic cellular manufacturing and supply chain design with consideration of various issues such as multi-plant locations, multiple markets, multi-time periods, reconfiguration, etc. The model objective was to minimize the sum of various costs such as facility/plant to market transportation cost, part holding cost at a facility/plant, part outsourcing cost, machine procurement cost, machine maintenance overhead cost, machine repair cost, production loss cost due to machine breakdown, machine operation cost, setup cost, tool consumption cost, inter-cell travel cost, intra-cell travel cost, and system reconfiguration cost for the entire planning time horizon. To study the model, three procedures—LINGO, artificial immune system, and hybrid artificial immune system—are used to perform computational experiment on some problems from existing literature. The best result generally is found by the hybrid artificial immune system algorithm. 相似文献
914.
“Secure Device Pairing” or “Secure First Connect” is the process of bootstrapping a secure channel between two previously unassociated devices over some (usually wireless) human-imperceptible communication channel. Absence of prior security context and common trust infrastructure open the door for the so-called Man-in-the-Middle and Evil Twin attacks. Mitigation of these attacks requires some level of user involvement in the device pairing process. Prior research yielded a number of technically sound methods relying on various auxiliary human-perceptible out-of-band channels, e.g., visual, acoustic and tactile. Such methods engage the user in authenticating information exchanged over the human-imperceptible channel, thus defending against MiTM attacks and forming the basis for secure pairing.This paper reports on a comprehensive and comparative evaluation of notable secure device pairing methods. This evaluation was obtained via a thorough analysis of these methods, in terms of both security and usability. The results help us identify methods best-suited for specific combinations of devices and human abilities. This work is an important step in understanding usability in one of the rare settings where a very wide range of users (not just specialists) are confronted with modern security technology. 相似文献
915.
R L Kalra H Kaur S Sharma S K Kapoor S S Chakraborty R B Kshirasagar R C Vaidya R B Sagade S B Shirolkar T S Dikshith R B Raizada M K Srivastava V Singh K V Nagarja K M Appaiah M A Srinivasa M U Rani S N Rao G S Toteja J Dasgupta P K Ghosh B N Saxena 《Food Additives & Contaminants》1999,16(10):411-417
Under a multicentre study conducted by the Indian Council of Medical Research, 2205 samples of dairy milk were collected from rural and urban areas of 12 states representing different geographical regions of India. These samples were analysed for residues of DDT and different isomers of HCH by gas-liquid chromatography. Analytical quality assurance between various participating laboratories was ensured through analysis of check samples. The residues of DDT and HCH were detected in more than 80% of samples analysed. Concentrations of DDT residues, alpha-HCH, beta-HCH, gamma-HCH and delta-HCH exceeded their maximum residue limits prescribed by the Ministry of Health and Family Welfare of the Indian Government in 37, 21, 42, 28 and 4% of the samples, respectively. Median values of DDT and HCH found in dairy milk in India were more than the corresponding values reported from most other countries. The results showed significant variations in the incidence as well as level of these contaminants in dairy milk from different regions of the country. 相似文献
916.
S. P. Koiry Vibha Saxena Dayanand Sutar S. Bhattacharya D. K. Aswal S. K. Gupta J. V. Yakhmi 《应用聚合物科学杂志》2007,103(1):595-599
Polyindole fibers upto a length of 1000 μm and ~ 25 μm in diameter have been reproducibly synthesized by interfacial polymerization, which was performed at a stationary interface of aqueous (FeCl3 solution)/organic (indole in dichloromethane) biphasic system. On the other hand, disturbing the aqueous/organic interface by constant stirring of solution—termed as bulk polymerization—resulted in globular (average size ~ 2 μm) polyindole. The results of Fourier transform infrared spectroscopy revealed that polymerization takes place at carbon atoms located at positions 2 and 3 in indole monomer, and this has explained origin of different polyindole morphology obtained in interfacial and bulk polymerization. Cyclic voltammograms recorded as a function of scan rate indicated a high electroactivity of the synthesized polyindole. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 595–599, 2007 相似文献
917.
The Industrial Assessment Center (IAC) at the University of Wisconsin-Milwaukee has worked with more than 500 manufacturing companies to identify energy and productivity saving opportunities for small and medium sized companies. The most common saving recommendations are summarized. The implementation rates of the recommendations were only about 40%. The logistic regression analysis is used to investigate the factors that affect the implementation rates of the recommendations in 147 manufacturing plants from seven different types of industries. Six possible factors affecting the implementation rates of the recommendations are investigated; payback period, sales, number of employees, plant area, annual working hours, and the industry type. It is determined that each type of industry deals differently with implementing the recommendations. Furthermore, the recommendation type (energy or productivity) and payback period are the main factors that affect the implementation rates. It was also found that the companies which run on full capacity or work more hours are less likely to implement the recommendations. 相似文献
918.
Software-implemented EDAC protection against SEUs 总被引:1,自引:0,他引:1
In many computer systems, the contents of memory are protected by an error detection and correction (EDAC) code. Bit-flips caused by single event upsets (SEU) are a well-known problem in memory chips; EDAC codes have been an effective solution to this problem. These codes are usually implemented in hardware using extra memory bits and encoding/decoding circuitry. In systems where EDAC hardware is not available, the reliability of the system can be improved by providing protection through software. Codes and techniques that can be used for software implementation of EDAC are discussed and compared. The implementation requirements and issues are discussed, and some solutions are presented. The paper discusses in detail how system-level and chip-level structures relate to multiple error correction. A simple solution is presented to make the EDAC scheme independent of these structures. The technique in this paper was implemented and used effectively in an actual space experiment. We have observed that SEU corrupt the operating system or programs of a computer system that does not have any EDAC for memory, forcing the system to be reset frequently. Protecting the entire memory (code and data) might not be practical in software. However this paper demonstrates that software-implemented EDAC is a low-cost solution that provides protection for code segments and can appreciably enhance the system availability in a low-radiation space environment 相似文献
919.
Thomas W. Custer Kuruthachalam Kannan Lin Tao Abhinav R. Saxena Bill Route 《Journal of Great Lakes research》2009
In 2007 archived great blue heron (Ardea herodias) eggs collected from Indiana Dunes National Lakeshore, IN, (Indiana Dunes) in 1993 were analyzed for 11 perfluorinated compounds (PFCs) and 7 polybrominated diphenyl ethers (PBDEs). Concentrations of perfluorooctane sulfonate, the major contributor to total PFC concentrations, were below the toxicity thresholds estimated for bobwhite quail (Colinus virginianus) and mallards (Anas platyrhynchos), but within the toxicity threshold estimated for white leghorn chickens (Gallus domesticus). The ranking of PBDE congener concentrations by percent concentration (PBDE-47 > -99 > -100 > -153 > -154 > -28 > -183) was consistent with the Penta-PBDE formulation. Total PBDE concentrations in great blue heron eggs from Indiana Dunes were elevated and probably reflect local contamination from highly urbanized and industrialized inputs into Lake Michigan. Polybrominated diphenyl ether concentrations were within levels associated with altered reproductive behavior in other avian species and based on trends in other Great Lakes birds are probably higher today. 相似文献
920.
Bhupendra Singh Ken Subhajit Aich V. K. Saxena 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(20):2458-2466
This work presents the results obtained from the experimental study on the effects of KOH treatment and its combustion behavior of high sulfur Indian coal. Coal was treated with 5–20% KOH (v/v) concentration for 6–24 h reaction time to identify the effects of KOH treatment on coal properties. Experimental results showed that upto 36.79% of total sulfur can be removed from coal with 20% KOH concentration and 24 h contact time at atmospheric condition. However, gross calorific value of coal decreased from 6800 to 6084 kcal/kg due to removal of combustibles from coal. Combustion characteristics of treated coal were assessed by Thermo-gravimetric analysis/ Differential thermo-gravimetric (TGA/DTG analysis). Further various combustion kinetic parameters like ignition temperature, peak temperature, burnout temperature, activation energy (E), and pre-exponential factor (A) are estimated. Experimental results show that the ignition temperature of coal decreased from 321°C to 252°C, peak temperature decreased from 459°C to 409°C due to changes in the coal matrix after desulfurization. The activation energy of coal calculated decreased from 79 to 45 kJ/mol due to desulfurization using 20% KOH concentration and 24 h reaction time. 相似文献