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101.
Lean philosophy: implementation in a forging company 总被引:2,自引:2,他引:0
Ajit Kumar Sahoo N. K. Singh Ravi Shankar M. K. Tiwari 《The International Journal of Advanced Manufacturing Technology》2008,36(5-6):451-462
This research addresses the implementation of lean philosophy in a forging company with a focus on radial forging production
flow lines. Here, the prime motive is to evolve and test several strategies to eliminate waste on the shop floor. In this
research, a systematic approach is suggested for the implementation of lean principles. This paper describes an application
of value stream mapping (VSM). Consequently, the present and future states of value stream maps are constructed to improve
the production process by identifying waste and its sources. Furthermore, Taguchi’s method of design of experiments is pursued
here to minimize the forging defects produced due to imperfect operating conditions. A noticeable reduction in set-up time
and work-in-process (WIP) inventory level is substantiated. Finally, we conclude with a discussion of managerial implications
and the future scope of research. 相似文献
102.
A new chromosome encoding method, named fuzzy coding, is proposed for representing real number parameters in a genetic algorithm. Fuzzy coding provides the value of a parameter on the basis of the optimum number of selected fuzzy sets and their effectiveness in terms of degree of membership. Thus, it represents the knowledge associated with each parameter and is an indirect method of encoding compared with alternatives, where the parameters are directly represented in the encoding. Fuzzy coding is described and compared with conventional binary coding, gray coding, and floating-point coding. Two test examples, along with neural identification of a nonlinear pH process from experimental data, are studied. It is shown that fuzzy coding is better than the conventional methods and is effective for parameter optimization in problems where the search space is complicated. 相似文献
103.
A. Sharma A. Agrawal 《Photonics Technology Letters, IEEE》2006,18(8):944-946
A novel split-step finite-difference method for wide-angle beam propagation is presented. The formulation allows solution of the second-order scalar wave equation without having to make the slowly varying envelope and one-way propagation approximations. The method is highly accurate and numerically efficient requiring only simple matrix multiplication for propagation. 相似文献
104.
105.
Time-series model for wireless fading channels in isotropic and nonisotropic scattering environments
An autoregressive (AR) model is presented for isotropic and nonisotropic scattering environments characterized by Rice factor 0/spl les/K相似文献
106.
M. Kangas J. Villegas N. Kumar T. Salmi D.Yu. Murzin F. Sandelin E. Harlin 《Catalysis Today》2005,100(3-4):363-366
An investigation of the effect of reaction conditions on product distribution in the skeletal isomerisation reaction of linear butenes has been carried out. The main reaction routes over ferrierite have been identified. Beside the main product isobutene, major by-product formation occurs. The unwanted reactions include dimerisation of butene to form octenes, hydrogen transfer yielding small amounts of saturated C3 and C4 hydrocarbons and disproportionation producing propene and pentenes. The most abundant by-products were pentene and propene, though these were not formed in equimolar amounts as could be expected. Oligomerisation experiments of propene over ferrierite produced large amounts of butene and pentene, revealing the presence of adsorbed nonene. The cracking of this surface species to hexene and propene is the most likely reaction route for the excess propene formation. This additional path to propene formation operates mainly at temperatures above 623 K. 相似文献
107.
V Kumar PM Carabateas JA Dority WG Earley JP Mallamo C Subramanyam LD Aimone B Ault DL DeHaven Hudkins MS Miller 《Canadian Metallurgical Quarterly》1995,38(10):1826-1830
Replacement of the pyridinium ring of 6,11-ethanobenzo[b]quinolizinium cations with thiazolium (4a and 4b) and N-methylimidazolium (4c and 4d) resulted in equipotent compounds in the [3H]TCP binding assay. The corresponding N-methyl-1,2,4-triazolium analogs were less potent in this assay. The thiazolium derivative 4b, with a Ki = 2.9 nM, is being evaluated as a possible neuroprotective N-methyl-D-aspartic acid (NMDA) antagonist. 相似文献
108.
A Notghi R Hutchinson D Kumar NB Smith LK Harding 《Canadian Metallurgical Quarterly》1994,35(7):976-981
Segmental colonic transit has been measured in 101 patients. Two MBq of 111Indium absorbed on resin pellets and encapsulated in an enteric coated capsule was given at 7 00 am. Hourly images during the first day, and three images during each subsequent day were acquired for up to three days. Using all scan and patient data the scans were categorised in one of the five patterns of colonic transit: normal, rapid, right delay, left delay, or generalised delay. The geometric centres and per cent activity at each time point was compared between the five groups of colonic transit patients to find the best time for imaging and so to distinguish the five groups. During the first day, early images did not help in diagnosis of patterns of transit, however, in the later images (six hours onwards after the ingestion of the activity) the rapid transit groups could be identified. Images at 27 and 51 hours were both required to distinguish all five groups of patients from each other. Only in the 'normal' transit patients was there some excretion of the activity during the course of the second day, otherwise there was no difference in the images taken in the course of a day (second or third day). A simplified protocol requires a minimum of three images to distinguish all five patterns of colonic transit. The activity should be ingested in the morning (7 00 am) and the first image taken at the end of the working day (8-10 hours after ingestion), the second image on the morning of the second day, and the third image during the course of the third day. This simple protocol would provide all the clinically relevant information necessary for correct classification of the colonic transit. 相似文献
109.
110.
JF DeFrance S Sands FC Schweitzer L Ginsberg JC Sharma 《Canadian Metallurgical Quarterly》1997,9(4):283-293
The purpose of this article is to deliberate the moral and legal dilemma entailed in the weapon of the labour strike as a pressure tactic on the Israeli Finance Ministry regarding job slots, budgets and, in effect, violating the collective agreement signed by the nurses and impairing patients' treatment, as opposed to refraining from striking and suffering the heavy burden of work, the lack of trained personnel, low wages, and the inability to give patients proper, high quality treatment. 相似文献