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Wireless Personal Communications - The rapid development of Information and Communication Technology and the growing number of devices connected to the Internet make the Internet of Things (IoT) as... 相似文献
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Software reliability is one of the most important quality attributes of commercial software. During software testing, software reliability growth models (SRGMs) are commonly used to describe the phenomenon of failure occurrence and/or fault removal which consequently enhancements software reliability. Large software systems are developed by integrating a number of relatively small and independent modules, which are tested independently during module testing phase. The amount of testing resource available is limited which is desired to be consumed judiciously so as to optimize the testing process. In this paper we formulate a resource allocation problem of minimizing the cost of software testing under available amount of testing resource, given a reliability constraint. We use a flexible SRGM considering testing effort which, depending upon the values of parameters, can describe either exponential or S-shaped failure pattern of software modules. A systematic and sequential Algorithm is proposed to solve the optimization problem formulated. Numerical examples are given to illustrate the formulation and solution procedures. Sensitivity analysis is performed to examine the behavior of some parameters of SRGM with most significant influence. 相似文献
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(续接本刊2007年第7期第36页)2电子废物管理方式和立法提案2.1延伸生产者责任制延伸生产者责任制(EPR)作为废物管理的新模式得以广泛推广。OECD将EPR定义为一种新的环境制度,在该制度下,生产者对其产品的责任延伸到产品销售后的整个生命周期,包括最终处置(OECD,2001)。与污染者付费原则一致, 相似文献
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Girish M. Deshmukh Aparna Shete Deepali M. Pawar 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2013,88(3):432-436
BACKGROUND: Oxidative absorption of hydrogen sulfide into a solution of ferric chelates is studied in a stirred cell glass reactor. The experiments were performed to investigate the degradation of chelates sodium salt of nitrilotriacetic acid (NTA) (Merck), ethylenediaminetetraacetic acid diadisodium salt (EDTA) and diethylenetriaminepentaacetic acid (DTPA) at 313 K, pH 6, iron concentration 10 000 g L?1 and Fe:chelate molar ratio 1:2. RESULTS: Oxidative absorption of hydrogen sulfide into a solution of Fe‐NTA was found to be more successful, therefore, further experiments with 10%, 50% and 100% concentrations of hydrogen sulfide were performed. It was shown that this process is applicable for removal of low and high concentrations of hydrogen sulfide. The effect of antioxidants using sodium thiosulfate was also studied in order to minimize degradation of NTA. The kinetics were studied and it was observed that the reaction appeared to be first order in ferric chelate with rate constants for 100, 50 and 10% hydrogen sulfide concentration: 0.035, 0.013 and 0.019 h?1, respectively. CONCLUSIONS: Gas sweetening processes have commercial importance in natural gases, refinery of gases and biogas processing. Desulphurization and cleaning (i.e. removal of H2S and CO2) of petroleum gas and biogas is important to make the gas methane rich and to increase the calorific value of fuel. The same techniques of desulphurization and cleaning can be used for treating natural gas or petroleum gas. The desulphurization and cleaning processes can minimize the atmospheric emission of gases like SOx, NOx and CO. As the iron chelate based process is based on the principle of redox reaction of metal chelate with hydrogen sulfide, this method is very useful for desulphurization of petroleum gas and biogas. This work studied the effective use of Fe‐NTA solution for removal of high to low concentrations of H2S as found in biogas and industrial waste gases. © 2012 Society of Chemical Industry 相似文献
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Single and binary mixtures of aqueous extracts of red sandalwood (RSW) with aqueous extract of other natural dyes like manjistha (MJ), jackfruit wood (JFW), marigold (MG), sappan wood (SW) and babool (BL) in different proportions are applied on bleached jute fabric for its dyeing after double pre-mordanted with myrobolan and aluminium sulphate applied in sequence under optimised conditions of mordanting with effects of use of different proportions of binary mixture of selective natural dyes on colour strength and other colour. Parameters and colour fastness properties have been investigated. Compatibility of selective binary mixture of dyes was also judged by a relatively newer colour index parameter established earlier from this laboratory. Binary of mixture of RSW and MJ is found to be most compatible with rating 4 (in 0–5 scale), and mixture of RSW:MG and RSW:JFW is found to have average compatibility having rating 3. Dyed fabric samples have also been further treated with cationic dye-fixing agents namely N-cetyl-N-trimethylammonium bromide (CTAB), cetrimide and Sandofix-HCF to improve wash fastness. Treatment with 2% CTAB or Sandofix-HCF improves the wash fastness to nearly 1 unit. Treatment with 1% benztriazole improves the light fastness of natural dyed jute textiles nearly half to one unit. The possible chemistry and mechanisms for such improvement in wash fastness by CTAB and improvement of light fastness by benztriazole for jute have also been discussed to explain the observed effects. 相似文献
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Vikas Goel Deepali Gautam Amit Gupta Sachin Kumar 《International Journal of Communication Systems》2019,32(16)
Wireless broadcasting is the new emerging standard for disseminating the information. It also exploits the feature of mobile computing environment, i.e., an asymmetric environment where the bandwidth of downloading is much higher than the bandwidth of uploading. Due to the small devices, created to hold the feature of portability, various difficulties are imposed on the system. The mobile client follows some energy restricted traits to be efficient. Those traits are access time and tuning time. Access time basically tells the efficiency of the system by specifying how fast a user may get data. But tuning time measures the battery life of the device. In this paper, we have proposed (1, Xm) method to deal with these. Here, Xm basically implies the XML data passing on to the multiple channels. In this technique, we have sent data by indexing onto two different channels: index and data channel. We have analyzed the performance of the proposed indexing technique. To prove its validity, the improved results are compared with the former indexing techniques analytically and experimentally. 相似文献
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The behaviour of heterobifunctional reactive dyes, containing a monochlorotriazine and a vinyl sulphone group, on silk has been investigated. Maximum exhaustion and fixation were obtained in a neutral medium at 90d? C. The addition of sodium sulphate was found to promote the exhaustion of reactive dyes at pH values above the isoelectric point of silk. A reduction in the solubility of dyed silk indicated that crosslinks were formed with bifunctional reactive dyes. 相似文献
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Anjali Arora Deepti Gupta Deepali Rastogi Mohan Gulrajani 《Coloration Technology》2012,128(5):350-355
The roots of Arnebia nobilis have traditionally been used as a colorant in food and cosmetic preparations. The deep red colour obtained is attributed to the presence of shikonin and its isomer alkannin and their derivatives. In this study, five colouring components were extracted from the roots of A. nobilis. These were separated and purified chromatographically and characterised using various spectrophotometric techniques. Three of the five components were identified. The major component was found to be alkannin β, β‐dimethylacrylate [5,8‐dihydroxy‐2‐(1′‐β, β‐dimethylacryloxy‐4′‐methylpent‐3′‐enyl)‐1,4‐naphthoquinone], accounting for nearly 25% of the total colouring matter. Alkannin acetate [2‐(1′‐acetoxy‐4′‐methylpent‐3′‐enyl)‐5,8‐dihydroxy‐1,4‐naphthoquinone] made up ca. 8% and shikonin [(5,8‐dihydroxy‐4′‐methylpent‐3′‐enyl)‐1,4‐naphthoquinone] contributed ca. 6% of the colouring matter. Polyester was dyed pink, nylon was dyed blue and all other substrates acquired a purple hue under similar dyeing conditions. The dyed fabrics showed excellent wash, rub and perspiration fastness; however, light fastness was found to be poor. 相似文献
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This paper presents the use of artificial neural network for performance analysis of a semi transparent hybrid photovoltaic thermal double pass air collector for four weather conditions (a, b, c and d type) of New Delhi. The MATLAB 7.1 neural networks toolbox has been used for defining and training of ANN for calculations of thermal energy, electrical energy, overall thermal energy and overall exergy. The ANN model uses ambient air temperature, global solar radiation, diffuse radiation and number of clear days as input parameters for four weather conditions. The transfer function, neural network configuration and learning parameters have been selected based on highest convergence during training and testing of network. About 2000 sets of data from four weather stations (Bangalore, Mumbai, Srinagar, and Jodhpur) have been given as input for training and data of the fifth weather station (New Delhi) has been used for testing purpose. It has been observed that the best transfer function for a given configuration is logsig. The feedforward back-propagation algorithm has been used in this analysis. Further the results of ANN model have been compared with analytical values on the basis of root mean square error. 相似文献
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Yu Cheng Pavlina Vechtova Zoltan Fussy Jan Sterba Zuzana Linhartov Marek Rodina Vladimíra Tu
kov David Gela Azin Mohagheghi Samarin Ievgen Lebeda Miaomiao Xin Songpei Zhang Deepali Rahi Otomar Linhart 《International journal of molecular sciences》2021,22(11)
The purpose of the current study was to analyze phenotypic and functional characteristics of common carp (Cyprinus carpio) spermatozoa during in vitro aging and to investigate whether global DNA methylation is affected by sperm aging. Milt was collected from five individual males, stored in vitro on ice in a refrigerator for up to 96 h post stripping (HPS) and used to fertilize eggs with intervals of 1, 24 and 96 h. Computer-assisted sperm analysis and a S3e Cell Sorter was employed to determine the spermatozoa phenotypic characteristics (motility, velocity, concentration and viability). In addition, pH and osmolality of the seminal fluid and the capacity of the spermatozoa to fertilize, hatching rate and health of the resulting embryos were examined at different aging times. Whole-genome bisulfite sequencing was used to compare the global and gene-specific DNA methylation in fresh and aged spermatozoa. The results demonstrated that spermatozoa aging in common carp significantly affects their performance and thus the success of artificial fertilization. The methylation level at the cytosine-phosphate-guanine (CpG) sites increased significantly with 24 HPS spermatozoa compared to the fresh group at 1 HPS and then decreased significantly at 96 HPS. A more detailed investigation of gene specific differences in the DNA methylation was hindered by incomplete annotation of the C. carpio genome in the public databases. 相似文献