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81.
82.
In the future, applications will need to execute in a ubiquitous environment with varying network conditions (connectivity, bandwidth, etc.) and system constraints (e.g., power and storage). The distributed object paradigm is often used to facilitate the development of large-scale distributed applications. However, the traditional object messaging layer operates with limited awareness of underlying system and network conditions, whereas current system and network monitoring tools operate at the network layer with little awareness of application-level object communication requirements. This article explores the possibility, mechanisms and benefits of filling the gap between object messaging and system monitoring. We introduce connection abstraction as the mechanism for these two layers to communicate and exchange information. Through this integration, object messaging can proactively adapt to changing system conditions; system monitoring policies and parameters can be optimized based on interobject communication properties. 相似文献
83.
In day today's applications, it is obligatory to devise the usage of diesel in an economic and environmentally benign way. The present work was aimed at studying the performance, emission and combustion characteristics of a four-stroke diesel engine by adding n-pentane at different proportions such as 2%, 4%, 6%, 8% and 10% by volume with diesel. The performance, combustion and emission characteristics obtained from the experiment revealed that the addition of n-pentane augments the brake thermal efficiency of the engine. At full load, the brake thermal efficiency increased by 3.17% for an addition of 6% n-pentane, 4.31% for an addition of 8% n-pentane and 6.36% for an addition of 10% n-pentane. From the emission test, it was concluded that at full load, the NOx emission decreased by 8.67% for an addition of 6% n-pentane, 17.43% for an addition of 8% n-pentane and 18.09% for an addition of 10% n-pentane. 相似文献
84.
85.
Venkatasubramanian Sivakumar Gopalaraman Swaminathan Paruchuri Gangadhar Rao Thirumalachari Ramasami 《Chemical Engineering and Processing: Process Intensification》2008,47(12):2076-2083
Leather is a unique porous material, which is composed of a three-dimensional weave of tanned collagen fibre bundles. Collagen is a fibrous protein well organized in the formation of skin as building block. This paper studies the use of ultrasound in improving the diffusion process through porous skin/leather matrix. A diffusion model for leather processing has been proposed taking into account of pore characteristics in leather. Dye diffusion experiments have been carried out with leather and powdered leather to show the influence of ultrasound under two different diffusion conditions. Apparent diffusion coefficient (D) of dye through leather matrix has been calculated from the experimental dye uptake data. The results indicate that the use of ultrasound could achieve, 16.2 and 8.56 times improvement in D value for leather at 50 °C and 30 °C, respectively as compared to 2.99 and 1.55 times for powdered leather. Scanning electron microscopy (SEM) analysis of leather has also been performed which shows that fibre structure and morphology are not affected by the use of ultrasound. This study throws some light on enhanced transport through porous materials of complex nature such as skin/leather using ultrasound. 相似文献
86.
Characterization of a radiation-induced stress response communicated in vivo between zebrafish 总被引:1,自引:0,他引:1
Mothersill C Smith RW Agnihotri N Seymour CB 《Environmental science & technology》2007,41(9):3382-3387
Radiation-induced communication of stress signals between rainbow trout (Oncorhynchus mykiss W) have recently been described by this group and linked to the bystander effect. This paper addresses the question of whether another totally unrelated fish species (Danio rerio L) can demonstrate the effect and also looks at attenuation of both the bystander signal, from irradiated fish, and the bystander effect, in naive fish. The data show that zebrafish produce bystander signals, and that, as with rainbow trout these can affect na?ve (i.e., non-irradiated) fish placed in water with X-rayed fish or in water previously occupied by X-rayed fish. Skin explants from directly X-rayed fish still reduce HPV-G reporter cell growth 6 h after X-ray, but the bystander signal to na?ve fish is lost. Twelve h after X-ray the signal is lost in X-rayed fish. The bystander effect is also attenuated if induction was by placing na?ve fish in water which previously held the X-rayed fish. However, the effect is retained if induction was by placing X-rayed and na?ve fish together. This suggests the signal is not retained by water for long periods of time. Individual fish data reveal unique responses by bystander fish which could indicate varying levels of sensitivity to signal strength among individuals. 相似文献
87.
Chitosan was chemically modified by introducing xanthate group onto its backbone using carbondisulfide under alkaline conditions. The chemically modified chitosan flakes (CMC) was used as an adsorbent for the removal of cadmium ions from electroplating waste effluent under laboratory conditions. CMC was found to be far more efficient than the conventionally used adsorbent activated carbon. The maximum uptake of cadmium by CMC in batch studies was found to be 357.14 mg/g at an optimum pH of 8.0 whereas for plain chitosan flakes it was 85.47 mg/g. Since electroplating wastewater contains cyanide in appreciable concentrations, interference of cyanide ions in cadmium adsorption was found to be very significant. This problem could be easily overcome by using higher doses of CMC, however, activated carbon was not found to be effective even at higher doses. Due to the high formation constant of cadmium with xanthate and adsorption was carried out at pH 8, cations like Pb(II), Cu(II), Ni(II) and Zn(II) did not interfere in the adsorption. Dynamics of the sorption process were studied and the values of rate constant of adsorption were calculated. Desorption of the bound cadmium from CMC was accomplished with 0.01 N H(2)SO(4). The data from regeneration efficiencies for 10 cycles evidenced the reusability of CMC in the treatment of cadmium-laden wastewater. 相似文献
88.
ABSTRACT Mining integrates the skill of many engineering disciplines. Within these disciplines lies experience and expertise found in not other industry. To capture and widely apply this expertise is the challenge to developing the knowledge base expert systems The characteristics of plausible reasoning shared by medical diagnosis and mineral exploration are common, to some degree to many other evaluation tasks as well. Hence, the purpose of this paper is to illustrate, by a cast study of mining equipment selection, the general process of capturing and encoding human expertise into a mechanical realization. 相似文献
89.
Anjali Gupta M. Yunus Nalini Sankararamakrishnan 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(4):546-552
BACKGROUND: A study of the removal of arsenic from a sample of actual groundwater using crosslinked xanthated chitosan is described. RESULTS: Removal of As(III) and As(V) was studied at pH 7.5 under equilibrium and dynamic conditions. The equilibrium data were fitted to Langmuir and Freundlich adsorption models and the various model parameters evaluated. The monolayer adsorption capacity from the Langmuir model for xanthated chitosan flakes (XCF) (As(V) 20.0 ± 0.56 mg g?1; As(III) 33.0 ± 0.32 mg g?1) were lower than obtained for xanthated chitosan granules (XCB) (As(V) 36.0 ± 0.52 mg g?1; As(III) 48.0 ± 0.45 mg g?1). Adsorption of As (V) was unaffected by the presence of other anions while in the case of As(III) the presence of sulfate and silicate caused a 26.5–50.9% decrease in adsorption. A sample (940 bed volumes) of a groundwater spiked with 200 µg L?1 As(V) treated with XCF in column experiments reduced the arsenic concentration to < 10 µg L?1. The adsorbent was also successfully applied for the removal of total inorganic arsenic down to < 10 µg L?1 from real samples of arsenic‐contaminated groundwater. CONCLUSION: Xanthated chitosan was an efficient adsorbent for the removal of both forms of arsenic from groundwater under near neutral conditions. The presence of sulfur and the amino groups resulted in increased adsorption capacity of the sorbent. Copyright © 2012 Society of Chemical Industry 相似文献
90.
Emotion recognition, the most reliably validated component within the construct of emotional intelligence, is a complicated skill. Although emotion recognition skill is generally valued in the workplace, "eavesdropping," or relatively better recognition ability with emotions expressed through the less controllable "leaky" nonverbal channels, can have detrimental social and workplace consequences. In light of theory regarding positive emotion in organizations, as well as research on the consequences of perceiving negative information, the authors hypothesized and found an interaction between nonverbal channel and emotional valence in predicting workplace ratings from colleagues and supervisors. Ratings were higher for eavesdropping ability with positive emotion and lower for eavesdropping ability with negative emotion. The authors discuss implications for the complexity of interventions associated with emotional intelligence in workplace settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献