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101.

This paper presents a novel hybrid technique for the solution of economic load dispatch problem with valve point loading effect using Nelder–Mead (NM) simplex method and pattern search (PS) algorithm. Strength of globalized NM optimization algorithm has been employed to explore the search space for near optimal solution, and PS algorithm is used in combination with a search space reduction strategy, incorporating the principles of selection and stochastic reproduction, to fine-tune the result. The proposed technique has been applied to three different systems having 3, 13 and 40 generating units to demonstrate the application for small to large load dispatch set-up. The efficacy of the design scheme is established from comparison of the results with the state-of-the-art solvers, and it is found that the proposed scheme gives the best result in terms of mean cost while the average computational time is less than most of the reported methods.

  相似文献   
102.
In this article, a stochastic technique has been developed for the solution of nonlinear Riccati differential equation of fractional order. Feed-forward artificial neural network is employed for accurate mathematical modeling and learning of its weights is made with heuristic computational algorithm based on swarm intelligence. In this scheme, particle swarm optimization is used as a tool for the rapid global search method, and simulating annealing for efficient local search. The scheme is equally capable of solving the integer order or fractional order Riccati differential equations. Comparison of results was made with standard approximate analytic, as well as, stochastic numerical solvers and exact solutions.  相似文献   
103.
Carbazole, the well-known electron donor and hole-transporting organic light-emitting molecule was modified into 1,5-bis[N-carbazolyl]pentane (1,5-BNCP) by introducing the saturated pentane spacer. Such insertion fixed the certain space between growing polymer chains and demonstrated π–π stacking effect over its morphology and structure. Its contribution in improving the thermal stability and photosensitization was also investigated. The FT-IR and 1H NMR was used to characterize monomer. Morphology of subsequently polymerized material was seen under SEM. The position of polymerization and structural change were studied by FT-IR and XRD, respectively. Thermal study with reference to glass transition temperature and stability was analyzed by DSC and TGA. Optical properties of monomer and polymer were investigated by UV–visible and photoluminescent spectrophotometer. The material was found crystalline, thermally stable, highly photosensitized and white light emitter.  相似文献   
104.
Multimedia Tools and Applications - Information hiding is an active area of research where secret information is embedded in innocent-looking carriers such as images and videos for hiding its...  相似文献   
105.
The current investigations are presented to solve the fractional order HBV differential infection system (FO-HBV-DIS) with the response of antibody immune using the optimization based stochastic schemes of the Levenberg-Marquardt backpropagation (LMB) neural networks (NNs), i.e., LMBNNs. The FO-HBV-DIS with the response of antibody immune is categorized into five dynamics, healthy hepatocytes (H), capsids (D), infected hepatocytes (I), free virus (V) and antibodies (W). The investigations for three different FO variants have been tested numerically to solve the nonlinear FO-HBV-DIS. The data magnitudes are implemented 75% for training, 10% for certification and 15% for testing to solve the FO-HBV-DIS with the response of antibody immune. The numerical observations are achieved using the stochastic LMBNNs procedures for soling the FO-HBV-DIS with the response of antibody immune and comparison of the results is presented through the database Adams-Bashforth-Moulton approach. To authenticate the validity, competence, consistency, capability and exactness of the LMBNNs, the numerical presentations using the mean square error (MSE), error histograms (EHs), state transitions (STs), correlation and regression are accomplished.  相似文献   
106.
Today's consumers demand clean-label healthy products to which no artificial preservatives have been added. Distribution of fresh, safe raw meat or meat products requires reduced numbers of bacteria on its surface when it leaves the processing plant under strict maintenance of low temperatures throughout the supply chain. Means of controlling or even improving the food integrity aim to decontaminate the carcasses or products during or at the end of the production line. In the past decades, high-pressure processing (HPP) has been investigated as an alternative non-thermal preservation technology to match all these demands without compromising safety. HPP treatments could efficiently inactivate the vegetative microorganisms (related to foodborne diseases), but not spores. However, the combination of several non-thermal and conventional preservation techniques under the so-called hurdle technology has been explored to enhance their efficiency.  相似文献   
107.
Multimedia Tools and Applications - Term mismatch is a serious problem effecting the performance of information retrieval systems. The problem is more severe in biomedical domain where lot of term...  相似文献   
108.
Selective encryption techniques are usually used with resource limited communication infrastructure and devices like wireless networks and mobile devices, to reduce computational burden in securing large video data. This technique of securing a subset of data and hence reducing computation is usually considered a compromise on security. Similarly, if the data is not properly selected then the encryption procedure will result in compression inefficiency and format non-compliance. In this research work, these requirements of reduced computation with increased security, format compliance and compression efficiency are addressed. The security issue is addressed by carefully selecting the substitution boxes for the block cipher in use. For compression efficiency and compliance to the format the video data is selected such that the statistical and structural characteristics are preserved. In order to increase the security, different chaotic based substitution boxes, that are an integral part and the only nonlinear operation of the block ciphers, were studied for cryptographic strengths. The selected substitution boxes were used for permutation of selected video data and its encryption by integrating the S-box with the Advanced Encryption Standard and H.264/AVC. The video data selected to be secured, consist of discrete cosine transform coefficients; signs of trailing ones and non-zero transform coefficients. The discrete cosine transform coefficients were permuted using the selected S-box while the signs of trailing ones and non-zero transform coefficients were fully encrypted using AES with the modified S-box. Simulation results showed considerable visual degradation in the decoded video. It is also shown that the compression efficiency and format compliance was not compromised while keeping the computational load at minimum.  相似文献   
109.
Ag@polycarbazole coaxial nanocables (CNCs) have been successfully fabricated by the oxidative polymerization of carbazole over Ag nanowires (NWs) in acetonitrile. The morphology of Ag NWs and CNCs was studied by employing a transmission electron microscope (TEM) and a scanning electron microscope (SEM), which showed them to be a monodisperse material. The thickness of the polymer sheath was found to be 5 nm to 8 nm by observation under a high-resolution transmission electron microscope (HR-TEM). Energy dispersive X-ray spectroscopy (EDS), FT-IR and Raman measurements were used to characterize the polymer sheath, which demonstrated it to be a carbon material in polycarbazole form. X-ray photoelectron spectroscopy (XPS) was used for an interfacial study, which revealed that Ag surface atoms remained intact during polymer growth. In the end, zeta potential showed that the dispersion stability of Ag NWs increased due to polymer encapsulation, which is significant to obtain a particular alignment for anisotropic measurement of electrical conductivity.  相似文献   
110.
Lysozyme is a commercially valuable enzyme, and is applied in many fields, concerning products such as foods, drugs, and the like. In this work, lysozyme was isolated and purified from buffalo milk using sephadex G-50 and cation exchanger carboxymethyl cellulose. Lysozyme active fractions from buffalo milk were assayed against Gram positive substrate Micrococcus luteus at 450 nm and a decline in absorbance of 0.001 per min was observed. The optimum activity of lysozyme (158.3 ± 1.7 units/mL) was at 7.5 pH and 37°C temperature. Lysozyme activity at pasteurization temperatures 62.5°C, 30 min and 75°C, 15 s were (156.08 ± 1.03 and 156 ± 2 units/mL) not affected significantly; however, 47% activity of lysozyme was reduced at 100°C for 5 min. Antibacterial susceptibility testing of lysozyme (chicken egg white lysozyme and buffalo milk lysozyme) was performed on Micrococcus luteus (ATCC 4698) and Escherichia coli (ATCC 25235). Both lysozymes showed no inhibition effect against Escherichia coli.  相似文献   
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