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991.
Amal Badshah Khattak Aurang Zeb Maazuulah Khan Nizakat Bibi Ihsanullah Mohammad Saeed Khattak 《Food chemistry》2007,103(1):115-120
Effects of germination time and illuminations on sprout yield, biosynthesis of ascorbic acid, cooking ability and moisture accumulation in chickpeas were significant (p ? 0.01). Green light had the highest promoting effect on the ascorbic acid level (40.59 mg/100 g) as compared to other illuminations but significantly reduced the sprout yield (188.6 g) as compared to dark, fluorescence and γ-rays illuminations with significantly high sprout yield (196 g) and imbibing moisture (51%). Cooking time was reduced by 43% due to γ-rays in un-soaked seed. Cooking time increased in all treated chickpea samples after 24 h germination and thereafter decreased significantly. Red light significantly increased the cooking time (68.44 min) followed by fluorescent (64.5 min), yellow (61.8 min) and green light (60.9 min). The results indicated that germination of chickpea under green light was an effective process in enhancing ascorbic acid content while dark, fluorescence and γ-rays were effective in promoting sprout growth and to some extent biosynthesis of ascorbic acid. 相似文献
992.
In supply chain management (SCM), multi-product and multi-period models are usually used to select the suppliers. In the real world of SCM, however, there are normally several echelons which need to be integrated into inventory management. This paper presents a hybrid intelligent algorithm, based on the push SCM, which uses a fuzzy neural network and a genetic algorithm to forecast the rate of demand, determine the material planning and select the optimal supplier. We test the proposed algorithm in a case study conducted in Iran. 相似文献
993.
Mohammad Ilyas 《Computers & Industrial Engineering》1987,13(1-4):237-241
This paper deals with internetworking aspects of local area networks (LANs) with other local area networks and/or long-haul networks. Two types of LAN topologies are considered: bus and ring. Internetworking topologies discussed in this paper include, (i) networking of ring LANs via a bus LAN, (ii) networking of ring LANs via a ring LAN, (iii) networking of bus LANs via a bus and (iv) networking of LANs to long-haul networks. Advantages and disadvantages of these topologies are discussed in terms of their performance and other features. 相似文献
994.
Mohammad Rezaul Karim Kwon Taek Lim Mu Sang Lee Ketack Kim Jeong Hyun Yeum 《Synthetic Metals》2009,159(3-4):209-213
Sulfonated polyaniline–titanium dioxide (SPAni–TiO2) hybrid composites have been synthesized by using a new strategy in one-pot system of UV-cured polymerization method. Aqueous solution of aniline and orthoanilinic acid comonomers, a free-radical oxidant and titania precursor were irradiated by UV rays. Hydrolysis and reprecipitation of the titania precursor in aqueous aniline and orthoanilic acid lead to the formation of titanium dioxide particles which in turn catalyze oxidation of comonomers to sulfonated polyaniline. The resultant SPAni–TiO2 composites were characterized by using different spectroscopy analyses like X-ray diffraction, UV–visible (UV–vis) and infrared spectroscopy. The UV–vis absorption bands revealed that SPAni–TiO2 nanocomposites are optically active and the blue-shifted peaks due to the presence of titania within the SPAni matrix. Scanning electron microscopy and transmission electron microscopy of the nanocomposite showed a uniform size distribution with spherical and granular morphology. Thermogravimetric analysis revealed that the SPAni–TiO2 composites have a good thermal stability than the pristine SPAni. 相似文献
995.
Recently, the Shuaiba Refinery of Kuwait National Petroleum Company (KNPC) conducted a test run using mixed NiMo/CoMo catalysts in one of the H–Oil reactors to verify the specifications of a CoMo catalyst. However, reduced unit performance and unstable operation were experienced. This led to the unit shut-down and process time loss. To search the causes for the different reactor behaviours, a research work was undertaken in the Petroleum Technology Department at Kuwait Institute for Scientific Research (KISR). It had found that the hydrodynamics of the mixed NiMo/CoMo and CoMo catalysts in a cold flow ebullated-bed reactor (EBR) were very different than NiMo catalyst alone. 相似文献
996.
997.
Arin Hovanessian Mohammad‐Ali Norouzi 《IEEJ Transactions on Electrical and Electronic Engineering》2016,11(Z1):S68-S77
In this paper, islanding detection in the presence of different technologies of distributed generations (DGs) is discussed. Three types of DGs, namely a synchronous generator (SG), a wind energy conversion system (WECS), and a photovoltaic (PV) system, with distribution network parameters as well as linear and nonlinear loads are simulated using the Power System Computer Aided Design/Electromagnetic Transients Including DC (PSCAD/EMTDC) software. To detect the island state, a comprehensive islanding detection algorithm based on wavelet transform (WT) and rate of change of frequency (ROCOF) relay method is considered. To determine the islanding threshold value, the voltage and frequency values of sensitive buses are sampled at regular intervals, and the signals are analyzed with WT using MATLAB. The proposed algorithm could detect the exact island state definitively with the consideration of various disturbance signals such as capacitor bank switching, induction motor switching, and the sudden disconnection of power sources and loads from different buses of the distribution network. The results of the simulation are validated with the logic of ROCOF relay islanding detection method, which determines the accuracy threshold value when the power generation and load consumption difference is negligible. In addition, the proposed algorithm based on the rested DG's output power in the islanding state can supply prioritized loads based on thier importance. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
998.
This study investigates the effect of clay addition on the broadband dielectric properties of multi‐walled carbon nanotube/polyvinylidene fluoride (MWCNT/PVDF) composites, that is, frequency range of 101−106 Hz. Different loadings of MWCNT and clay were used for the preparation of three‐phase (MWCNT/Clay/PVDF) nanocomposites via melt‐mixing method. The crystalline structure and morphology of nanocomposites were examined by employing characterization techniques such as X‐ray diffraction, transmission electron microscopy, and differential scanning calorimetry. The dielectric spectroscopy showed that introducing clay into the MWCNT/PVDF nanocomposites at a critical MWCNT concentration improved dielectric properties tremendously. It was interestingly observed that the incorporation of a specific amount of clay, that is, 1.0 wt%, into the (MWCNT/PVDF) nanocomposite at a critical MWCNT loading, that is, 0.5 wt% MWCNT, resulted in a huge increase in the dielectric permittivity (670% at 100 Hz) and a considerable reduction in the dissipation factor (68% at 100 Hz). POLYM. COMPOS., 161–167, 2016. © 2014 Society of Plastics Engineers 相似文献
999.
Mohammad Mazaheri Yousef S. Kavian Hamid Sharif Habib F. Rashvand 《Wireless Communications and Mobile Computing》2016,16(15):2406-2418
Because of the practical limitations of the energy and processing capabilities, the deployment of many Wireless Sensor Networks (WSN) is facing two main challenges of increasing network lifetime and reducing End to End Delay (EED) which become critical when the nodes are mobile and use non‐rechargeable energy sources. One way to help to extend network lifetime is using fuzzy logic in a form of artificial intelligence. To this end we propose a new routing protocol for using mobile WSNs, which holds the nodes in an equal level of energy and decreases energy dissipation of the network. An optimum path is selected based on the cost of each node to increase network lifetime. In order to lessen EED, we also attempt to design a novel zoning‐scheme for the network area. In this scheme, zonation is dynamic and works based on the Data Link (DL) position. The simulation result shows a significant improvement in lifetime and EED by proposed protocol compared with existing protocols. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
1000.
Since electricity demand is increasing continuously, it is necessary to invest in expansion of distribution network capacity. From the asset management point of view, it is necessary to encourage the private sector to invest in distribution network. To do this, distribution network managers must provide important opportunities for private sector to profit from their investments. One of the options for private sector is to invest on distributed generations (DGs). In this regard, distribution company (DisCo) must sign power purchase agreement (PPA) with DG owners (DGOs). So, optimal siting, sizing and PPA rates from economic point of view are important challenges which are considered as the main contribution of this paper. The proposed methodology of this paper applies load and price uncertainties into the planning problem. The proposed scheme involves using non-dominated sorting genetic algorithms II (NSGA II), since it attains non-dominated solutions in which DisCo and the DGO can put their personal preferences into practice. To evaluate the effectiveness of the suggested method, the computer simulations are done on a 33-bus distribution network and the results are discussed. 相似文献