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1.
Nowadays, the web service has become the emerging communication technology where the interaction of each user is performed through the World Wide Web. However, the performance of the web service mechanism is degraded due to security flaws that occur throughout the Internet.. The user or service requester may not attain the relevant web service for their requirement. To overcome this problem, the newly developed multi-objective based Cuckoo Search (MCS) algorithm is proposed in this article. Initially, the input query model was built by the query keyword that is provided by the service requester. Then, the given query is matched with the database that hosts the web services that relates to input query. Among the various services, the user has to select the appropriate web service using the proposed algorithm. The MCS algorithm is newly designed by combining the Cuckoo Search algorithm and the QoS parameter based multiple objectives. Additionally, the new mathematical model of fitness is evaluated by the multi-objective parameters. Finally, the proposed algorithm exploits the fitness value to select the relevant web service for the user query. The experimental results are validated and performance is analyzed by the parameters of precision, recall, and F-measure. Thus, 86.6% of precision value was obtained by the proposed method, which ensured provision of the appropriate web service.  相似文献   
2.
The use of diverse knowledge sources in text recognition and in correction of letter substitution errors in words of text is considered. Three knowledge sources are defined: channel characteristics as probabilities that observed letters are corruptions of other letters, bottom-up context as letter conditional probabilities (when the previous letters of the word are known), and top-down context as a lexicon. Two algorithms, one based on integrating the knowledge sources in a single step and the other based on sequentially cascading bottom-up and top-down processes, are compared in terms of computational/storage requirements and results of experimentation.  相似文献   
3.
Polyelectrolyte complex (PEC) membranes composed of chitosan (CS) and poly(methacrylic acid) (PMAA) were prepared by mixing the polymer solutions in different ratios. The chemical interaction and crystallinity of the resulting PEC membranes were respectively analyzed by Fourier transform infrared spectroscopy (FTIR) and wide‐angle X‐ray diffraction (WAXD). Differential scanning calorimetry (DSC) was used to characterize the thermal properties of the membranes. The membranes thus obtained were subjected to pervaporation (PV) separation of water‐dioxane mixtures. Among the PEC membranes, membrane containing 30 wt% ratio of PMAA (M‐3) exhibited the highest separation selectivity of 840 with a flux of 12.07 × 10?2 kg/m2h at 30°C at 15 wt% of water in the feed. By the incorporation of NaY zeolite into PEC up to 5 wt%, we have been able to overcome the trade‐off phenomenon existing between flux and selectivity in PV process. From the temperature dependent diffusion and permeation values, the Arrhenius activation parameters were estimated. The resulting activation energy values obtained for water permeation (Epw) are much lower than those of dioxane permeation (Epo), suggesting that the developed membranes have higher separation efficiency for water‐dioxane system. Based on the heat of sorption (ΔHs) values, the mode of sorption was discussed. POLYM. ENG. SCI., 56:715–724, 2016. © 2016 Society of Plastics Engineers  相似文献   
4.
Structure, morphology, and electrical properties of 10 mol% of Nb2O5-activated yttrium barium titanate (BT) Ba(60-z)Ti(40-x)NbzYxO3 (BTY10Nb10), barium titanate (BT), and 10 mol% of Y2O3-activated BT were explored with calcination and sintering temperatures of 1000°C at 8 h and 1200°C at 6 h, respectively. The thermogravimetric and differential scanning calorimetry (TG–DSC) analysis reported that the total weight loss and residual mass of BT at 1300°C were 16.8 and 83.2%, respectively. The X-ray diffraction (XRD) pattern confirmed that BTY10Nb10 ceramics containing the BaNbO3 phase were developed. A Raman band of BT at 307 cm–1 unveiled a blue shift slightly for BTY10 to 298 cm–1 and for BTY10Nb10 to 306 cm–1. Average pore area of the ferroelectric BTY10Nb10 was found to be 6.96 nm for the total scanning electron microscopy (SEM) image area of 20.31 nm. Formation of BT nanorods analyzed from transmission electron microscopy (TEM) has been reported in three samples that regulate surface roughness. Moreover, Nyquist diagram of BTY10Nb10 shows two overlapping semicircles as a function of frequency. Nanorod structures led to change the morphology and surface roughness. Recoverable energy storage density and energy storage efficiency were estimated as 2.63 µJ/cm3 and 57%, and BTY10Nb10 ferroelectric showed potential for energy storage applications due to changes in surface morphology and porosity.  相似文献   
5.
Potassium is deposited as kainite and/or carnallite by solar evaporation of sea and inland bitterns, respectively. The solubility of this natural kainite in water was found to be at 20 g magnesium chloride per 100 g water as against at 27.5 g obtained with synthetic kainite. As a result, the equilibrium data available from conventional phase diagrams were found to be not applicable for the conversion of kainite to potassium schoenite, an intermediate product to obtain potassium sulphate. Therefore applicability of the system K2Cl2-MgSO4-H2O to natural kainite was investigated and equilibria in reactions in slurries and optimum yields were worked out.  相似文献   
6.
The electrochromic (EC) behavior of fibrous reticulated WO3 films prepared from ammonium tungstate precursor by pulsed spray pyrolysis method was investigated. All the films were prepared using identical technological parameters and a thorough investigation of the electrochromic properties of the films deposited at 300 °C is reported. The structural properties were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochromic and optical properties were measured using cyclic voltammetry and ultraviolet (UV)-visible spectrophotometry. The films are amorphous and have a fibrous reticulate-like morphology having micron-size circular rings. The films show high transparency in the visible range and the optical band gap energy is about 3.1 eV. Electrical measurements show that the resistivity monotonically decreases as temperature increases, which indicates thermal hopping transport. The activation energy for hopping transport is of the order 4×10−4 eV. The electrochromic coloration efficiency (CE) is found to be 34 cm2/C at 630 nm.  相似文献   
7.
Mother liquor compositions during the solar evaporation of marine bitterns have been compared with corresponding isothermal equilibria in the NaCl-KCl-MgCl2-MgSO4-H2O system. The compositions indicate that on solar evaporation of bitterns, potassium is deposited solely in the form of kainite, and that co-deposition of free sylvite and epsomite does not take place. It is also shown that during solar evaporation, the concentration of potassium is relatively low and that of magnesium relatively high, resulting in a more efficient precipitation of potassium in solar evaporation than in the forced or isothermal evaporation of sea water or of pure salts.  相似文献   
8.
Materials with magneto-electric (ME) properties are of great importance because of their demand in electronic industries. Three dimensional nano-particles of the ME-composites having the general formula (1-x)CoCr0.3Fe1.7O4(CCFO)+(x)BaTiO3(BTO) (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) were obtained by comprising the piezoelectric-BTO and piezomagnetic-CCFO phases. The individual phases of CCFO and BTO were synthesized separately by ultrasonic irradiation assisted sonochemical and sol-gel routs. X-ray diffraction patterns (XRD) confirmed the well-crystalline nature of both the phases. BTO and CCFO phases were under tensile strain as confirmed by the variation in lattice constants with varying proportion of BTO and CCFO. An energy-dispersive X-ray spectroscopy spectrum confirmed the phase purity of the samples and stoichiometric concentration of elements. Magnetic properties were investigated by M ? H loop measurements and dielectric properties by using RF impedance analyzer. Dielectric constant increased with the increasing percentage of BTO. The maximum value of ME coefficient (24.7 mV/cm?Oe) is observed for the 60%CCFO+40%BTO sample. The obtained results were discussed in the light of grain size, strain and the basic properties of the individual phases. The prepared materials can be applicable in electronic devices where high magneto-electric coefficient is desirable.  相似文献   
9.
10.
A well designed production system secures environmental and internal fit. Environmental fit in a production system refers to alignment of manufacturing decisions to the external settings such as product and market. Internal fit implies that manufacturing decisions are mutually supportive. This paper develops a framework to analyse congruence of manufacturing decision areas in a production system. The framework considers six broad manufacturing decision areas. Based on the literature review, 54 decision types and alternative decision choices for each decision type are identified. The subjective and/or objective constructs to measure decision type are presented which should be useful in designing construct and in data gathering to conduct empirical research. Using the proposed framework, many research questions concerning the settings of several decision types for a specific type of production system can be generated and empirically tested.  相似文献   
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