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41.
Bikram K. Bahinipati Arun Kanda S.G. Deshmukh 《Computers & Industrial Engineering》2009,57(3):880-895
This paper aims to provide a generic quantitative model to comprehensively assess the degree of collaboration with individual horizontal collaboration initiatives with a view to check feasibility for satisfying the customer requirements. The analytic hierarchy process–fuzzy logic model (AHP–FLM) approach is chosen for developing the model, a method that is often used to tackle complex strategic decision making that calls for subjective judgment based on well-established logical reasoning, rather than on simple feeling and intuition. In the process, the complex and unstructured problem for ‘compatibility test’ is broken down into elements, and then a customized hierarchy structure is set up to demonstrate the relationship between different hierarchy levels and among these elements. Each element may have a different level of importance for the horizontal collaboration. A fuzzy rule based collaboration intensity index (CII) is developed to build up the relationships among these evaluation attributes. Synthesizing the generic relative importance and the forecasted degree of collaboration, the proposed approach can determine the success of the collaboration initiative. An illustrative example of a semiconductor industry supply chain (SSC) member that intends to partner with a potential and competing candidate enterprise is developed to demonstrate the applicability of the proposed fuzzy strategic alliance selection framework and to measure the effectiveness of a horizontal collaboration initiative. 相似文献
42.
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
43.
Machining feature-based similarity assessment algorithms for prismatic machined parts 总被引:4,自引:0,他引:4
This paper presents algorithms for identifying machined parts in a database that are similar to a given query part based on machining features. In this paper we only consider parts that are machined on 3-axis machining centers. We utilize reduced feature vectors consisting of machining feature access directions, feature types, feature volumes, feature dimensional tolerances and feature group cardinality as a basis for assessing shape similarity. We have defined a distance function between two sets of reduced feature vectors to assess the similarity between them from the machining effort point of view. To assess the similarity between the two parts, one set of reduced feature vectors is transformed in space using rigid body transformations with respect to the other set such that the distance between them is minimized. The distance between the two sets of aligned reduced feature vectors is used as a measure of similarity between the two parts. The existing machined parts are rank ordered based on the value of the distance with respect to the query part. The cost of previously machined parts that have a very small distance from the query part can be used as a basis for estimating the cost of machining the new part. 相似文献
44.
Lubrication is critical for minimizing wear in mechanical systems that operate for extended time periods. Developing lubricants that can be used in engineering systems without replenishment – particularly those that are environmentally friendly – is very important for increasing the functional lifetime of mechanical components. In the present investigation, extended duration pin-on-disk experiments were carried out to determine the relative performance of a wide range of lubricant combinations in a commercial brake valve assembly. In the experiments, the lubricants were initially applied to the disk surface but were not replenished over a sliding distance of more than 6000 m. The experimental results revealed that the environmentally friendly lubricant boric acid was highly ineffective for reducing the wear in the surfaces tested. When combined with a commercial transmission fluid, however, the boric acid mixture proved to be highly effective in terms of both friction and wear performance. Based on the success of the combined lubricant experiments, the boric acid was then mixed with canola oil to form a completely natural lubricant combination. Based on further pin-on-disk experiments, this lubricant combination yielded the best wear performance of all the lubricants tested. The importance of these results, as related to the use of the natural lubricant combination in other engineering systems such as sheet metal stamping, was subsequently ascertained and discussed. 相似文献
45.
46.
LP Ormerod A Charlett C Gilham JH Darbyshire JM Watson 《Canadian Metallurgical Quarterly》1998,53(3):176-181
Refractory hypotension with end-organ hypoperfusion is an ominous feature of inflammatory shock. In the past fifteen years, nitric oxide (a diffusible, short-lived product of arginine metabolism) has been found to be an important regulatory molecule in several areas of metabolism, including vascular tone control. Vascular endothelial cells constitutively produce low levels of nitric oxide that regulate blood pressure by mediating adjacent smooth-muscle relaxation. In an inflammatory shock state, cytokines, like interleukin-1 and tumor necrosis factor-alpha, induce a separate, high-output form of the enzyme that synthesizes nitric oxide in both endothelial and smooth-muscle cells. The ensuing high rates of nitric oxide formation result in extensive smooth-muscle relaxation, pressor refractory vasodilation, and--ultimately--shock. The concept of the pathogenesis of inflammatory shock explains many limitations of current therapies and may foster the development of new interventions to mitigate the effects of nitric oxide overproduction in this syndrome. 相似文献
47.
LP Nielsen T Bjerke MB Christensen M Skamling CG Peterson N Mygind R Dahl 《Canadian Metallurgical Quarterly》1998,53(8):778-785
BACKGROUND: The purpose was to study activation markers of the eosinophil granulocytes in seasonal allergic rhinitis, and the impact of topical steroid therapy thereupon. METHODS: Sixty-three rhinitis patients with monoallergy to grass were examined before and at peak pollen season. Blood eosinophil count, eosinophil cationic protein (ECP), and eosinophil peroxidase (EPO) in serum and nasal lavage fluid were measured. During the season, patients were randomized to treatment with intranasal fluticasone propionate 0.1 mg o.d. (n=26), 0.2 mg o.d. (n=25), or placebo (n=12). Six healthy persons served as controls. RESULTS: During the season, all parameters, except nasal lavage ECP, increased in the placebo group (P<0.001-P<0.05). Significant differences were seen between the steroid groups and the placebo group for all parameters (P<0.001-P<0.05). Higher eosinophil count (P<0.05), serum EPO (P<0.02), and nasal lavage EPO (P<0.05) were found in patients before season than in controls. The following winter, 44 patients returned for repeated measurement. Lower levels of nasal lavage EPO were observed for patients than levels at the beginning of the season (P<0.0001). CONCLUSIONS: Intranasal fluticasone propionate reduced inflammation of the nasal mucosa, demonstrated locally by nasal lavage ECP and EPO, and systemically by blood eosinophils, serum ECP, and serum EPO. EPO seemed more sensitive than ECP as indicator of allergic inflammation. EPO demonstrated some perennial eosinophil activity in hay fever patients, increasing locally during spring. 相似文献
48.
49.
The antennal lobes (ALs), the primary olfactory centers, of the moth Manduca sexta are sexually dimorphic. Only ALs of males possess the macroglomerular complex (MGC), the site of primary processing of information about the female's sex pheromone. To understand the development of identified, odor-specific olfactory glomeruli, we investigated the cellular events involved in the morphogenesis of the MGC by means of various fluorescence staining techniques and laser-scanning confocal microscopy. The MGC lies near the entrance of the antennal nerve into the AL of the adult male and comprises three glomeruli, the globular cumulus and two toroidal structures. The MGC forms during early stages of metamorphic adult development through a stereotyped sequence of coordinated changes in MGC-specific receptor axons, glial cells, and early-ingrowing projection neurons of the medial group of AL neurons. The MGC divisions are the earliest glomeruli to form in the male AL, and their basic organization is established within about 3 days after ingrowth of the first sensory axons. Despite their special anatomical features, the MGC glomeruli develop in a manner similar to that of the ordinary glomeruli. Comparison of the ALs of males and females reveals that two relatively large and early-developing glomeruli that are situated dorsolaterally in the female AL appear to be female-specific. Development of the sexually dimorphic glomeruli diverges immediately after the ingrowth of the first olfactory receptor axons, resulting in the formation of these large glomeruli in females and the MGC in males. 相似文献
50.
During fifties there were at most few tens of persons in this country who believed in the future of computers and cybernetics. One group of such enthusiasts, headed by Antonín Svoboda, was working at a construction of the first Czech computer SAPO. The other group tried to analyse, anticipate, and prepare in advance various applications for the new systemic conceptions and for the information processing machines. Members of both groups met for discussions which opened prospects to the future and influenced many of other activities for a long time. At the early sixties, the Czechoslovak Cybernetic Society was established at the Czechoslovak Academy of Sciences and in 1962 the Main Problem Committee for the Medical Cybernetics was founded at the Department of Health. It coordinated majority of the research programmes in the medical cybernetics and informatics. In 1967-1969 the Committee prepared an extensive project of a medical information system (ZIS), but its accomplishment was finally blocked by the then authorities. However, interests for that topics kept growing and the new working places equipped with available computer technology were formed at the health and clinical centres. The first tentative lectures in medical cybernetics and biocybernetics at our faculty were introduced into the students curricula in the late sixties. Thematically, medical cybernetics subsequently differentiated into the medical informatics, simulations of biological and medical systems, and the biosignal analysis. The growing interest enabled to hold conferences since the middle of seventies, some of which were held periodically, sometimes with international participation. It is not possible in brevity to include the whole spectrum to those goal-directed activities nor to appraise adequately their future significance. 相似文献