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21.
Journal of Signal Processing Systems - Segmentation of thigh tissues (muscle, fat, inter-muscular adipose tissue (IMAT), bone, and bone marrow) from magnetic resonance imaging (MRI) scans is useful...  相似文献   
22.

The edge computing model offers an ultimate platform to support scientific and real-time workflow-based applications over the edge of the network. However, scientific workflow scheduling and execution still facing challenges such as response time management and latency time. This leads to deal with the acquisition delay of servers, deployed at the edge of a network and reduces the overall completion time of workflow. Previous studies show that existing scheduling methods consider the static performance of the server and ignore the impact of resource acquisition delay when scheduling workflow tasks. Our proposed method presented a meta-heuristic algorithm to schedule the scientific workflow and minimize the overall completion time by properly managing the acquisition and transmission delays. We carry out extensive experiments and evaluations based on commercial clouds and various scientific workflow templates. The proposed method has approximately 7.7% better performance than the baseline algorithms, particularly in overall deadline constraint that gives a success rate.

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23.
Different approaches have been used to convert the waste materials into a clean syngas or other chemicals such as methanol. Among them, pyrolysis is a good candidate to produce the synthesis gas and volatile matters for industrial and refinery applications. In this work, we studied the kinetic and chemical behavior of three Iranian waste oils through a kinetic model and an experimental study. The experiments carried out in a micro-FB reactor, which is a good option for low emissions. Results showed that the reaction temperature and reaction rate are two of the most important factors for maximum conversion level of fuel. Results also showed an optimum value for reaction rate. The modeling results validated against the experimental measurements and found to be in good agreements.  相似文献   
24.
Water separated from crude oil and wastewater discharge from petroleum oil refineries contains significant quantity of dissolved hydrocarbons. Polycyclic aromatic hydrocarbons (PAHs) are major toxicants in wastewater of refineries. It is difficult to treat wastewater containing PAHs due to their recalcitrant property and low solubility. Conventional techniques for the treatment of wastewater are still a concern of toxicity. Electrochemical oxidation process has been found to be a favorable for treating wastewater. Electrodes with high stability and electrocatalytic activity are important factors for a successful electrochemical oxidation of toxic organics in wastewater. In this study titanium anodes were coated with tin, antimony and iridium oxide mixture from their respective salts by thermal decomposition method. FESEM and XRD used for surface characterization of Ti/SnO2–Sb2O5–IrO2 anode. Quantification of PAHs was done using GC–MS. Results confirm the presence of respective oxides on anode surface. Their electrocatalytic capability was tested for degradation of 16 priority PAHs in aqueous solution. Results reveal the complete degradation of naphthalene, acenaphthylene, acenaphthene and fluorene without using NaCl electrolyte. While in the presence of NaCl naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene and pyrene were completely removed. About 98% of total PAHs removal was found at all initial pH values 3, 6, and 9 in the presence of electrolyte. Current study will be helpful in improving quality of petroleum industry wastewater containing PAHs.  相似文献   
25.
Analytical expressions are obtained for predicting the harmonic and intermodulation performance of R-LED series networks. These expressions are in terms of the ordinary Bessel functions with arguments depenedent on the modulation index.  相似文献   
26.
In the present research work, a non-edible oil source Cucumis melo var. agrestis(wild melon) was systematically identified and studied for biodiesel production and its characterization. The extracted oil was 29.1% of total dry seed weight. The free fatty acid value of the oil was found to be 0.64%, and the single-step alkaline transesterification method was used for conversion of fatty acids into their respective methyl esters. The maximum conversion efficiency of fatty acids was obtained at 0.4 wt% Na OH(used as catalyst), 30%(methanol to oil, v/v) methanol amount, 60 ℃ reaction temperature,600-rpm agitation rate and 60-min reaction time. Under these optimal conditions, the conversion efficiency of fatty acid was 92%. However, in the case of KOH as catalyst, the highest conversion(85%) of fatty acids was obtained at 40%methanol to oil ratio, 1.28 wt% KOH, 60 ℃ reaction temperature, 600-rpm agitation rate and 45 min of reaction time.Qualitatively, biodiesel was characterized through Fourier transform infrared spectroscopy(FTIR) and gas chromatography and mass spectroscopy(GC–MS). FTIR results demonstrated a strong peak at 1742 cm~(-1), showing carbonyl groups(C=O)of methyl esters. However, GC–MS results showed the presence of twelve methyl esters comprised of lauric acid, myristic acid, palmitic acid, non-decanoic acid, hexadecanoic acid, octadecadienoic acid and octadecynoic acid. The fuel properties were found to fall within the range recommended by the international biodiesel standard, i.e., American Society of Testing Materials(ASTM): flash point of 91 ℃, density of 0.873 kg/L, viscosity of 5.35 c St, pour point of-13 ℃, cloud point of-10 ℃, total acid number of 0.242 mg KOH/g and sulfur content of 0.0043 wt%. The present work concluded the potential of wild melon seed oil as excellent non-edible source of bioenergy.  相似文献   
27.
Mobile Networks and Applications - In Wireless Sensor Networks (WSNs), energy-efficient routing is required to conserve the scarce resources of these networks. Various energy-efficient routing...  相似文献   
28.

In this paper, an algorithm is proposed for detection and joint estimation of parameters of multiple targets using rotating antenna array. This paper is sequel to our previous work addressing a two element antenna array only. Joint estimation of number of targets, the targets’ range, Doppler and their directions of arrivals is carried while the effects of antenna rotation are compensated for a multi element linear array. The effectiveness of the algorithm is verified by the simulation results carried out for an eight element array. The proposed algorithm is able to resolve targets with same range and Doppler. The computations of the proposed algorithm are calculated and comparison is also given with other algorithms.

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29.
Wireless Personal Communications - The number of aged and disabled people has been increasing worldwide. To look after these people is a big challenge in this era. However, scientists overcome the...  相似文献   
30.
The mobile cloud computing (MCC) has enriched the quality of services that the clients access from remote cloud‐based servers. The growth in the number of wireless users for MCC has further augmented the requirement for a robust and efficient authenticated key agreement mechanism. Formerly, the users would access cloud services from various cloud‐based service providers and authenticate one another only after communicating with the trusted third party (TTP). This requirement for the clients to access the TTP during each mutual authentication session, in earlier schemes, contributes to the redundant latency overheads for the protocol. Recently, Tsai et al have presented a bilinear pairing based multi‐server authentication (MSA) protocol, to bypass the TTP, at least during mutual authentication. The scheme construction works fine, as far as the elimination of TTP involvement for authentication has been concerned. However, Tsai et al scheme has been found vulnerable to server spoofing attack and desynchronization attack, and lacks smart card‐based user verification, which renders the protocol inapt for practical implementation in different access networks. Hence, we have proposed an improved model designed with bilinear pairing operations, countering the identified threats as posed to Tsai scheme. Additionally, the proposed scheme is backed up by performance evaluation and formal security analysis.  相似文献   
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