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41.
Fisher’s “Nile” example is a classic that involves a bivariate random variable (X,Y) having a joint probability density function given by f(x,y;𝜃) = exp(?𝜃x?𝜃?1y), 0<x,y<∞, where 𝜃>0 is a single unknown parameter. We develop (i) fixed-width and (ii) fixed-accuracy confidence intervals for 𝜃 with a preassigned confidence coe?cient. In problem (i), we develop a purely sequential estimation strategy along with its asymptotic properties. In problem (ii), we determine that a fixed-sample-size estimation strategy will su?ce and yet the requisite sample size would have to be found. We have done that both exactly as well as approximately and we report that for all practical purposes the approximations nearly provide the exact sample size whether it is small, moderate, or large. The last problem we address is bounded-accuracy fixed-sample-size estimation of P𝜃{X>Y}. All theoretical properties are adequately validated by large-scale simulations. 相似文献
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Theory of Constraints developed by E. M. Goldratt was initially applied to production scheduling and later to various areas such as Operations, Finance and Measures, Project Management, Marketing, Sales, Managing People, Strategy and Tactics. However, these applications were in engineering industries and products. The Strategic Thinking Processes of Theory of Constraints are designed to help combat an enormous problem faced by organizations--the tendency of organizations and their management to study, construct and implement solutions in isolation. In this case study, we applied the Theory of Constraints' Strategic Thinking Process in one of the leading integrated poultry businesses in India to identify and overcome the policy constraints in the business. After overcoming the policy constraints, overwhelming improvements in throughput and Inventories were observed. 相似文献
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Manjima Bhattacharya Riya Chakraborty Arjun Dey Ashok Kumar Mandal Anoop Kumar Mukhopadhyay 《Ceramics International》2013,39(2):999-1009
The present experiments were focused on nanoindentation behaviour and the attendant “micro-pop-in” in a dense (~95% of theoretical) coarse-grain (~20 μm) alumina ceramic as a function of loading rate variations at three constant peak loads in the range of 105–106 μN. Based on the experimental results here we report for the first time, to the best of our knowledge, an increase in intrinsic nano scale contact resistance as well as the nanohardness with the loading rate. These observations were explained in terms of the correlation between the nanoscale plasticity and shear stress active just underneath the nanoindenter. 相似文献
46.
Reductionin Listeria monocytogenes,Salmonella enterica and Escherichia coli O157:H7 in vitro and on tomato by sophorolipid and sanitiser as affected by temperature and storage time 下载免费PDF全文
Ocen M. Olanya Dike O. Ukuku Daniel K.Y. Solaiman Richard D. Ashby Brendan A. Niemira Sudarsan Mukhopadhyay 《International Journal of Food Science & Technology》2018,53(5):1303-1315
Increased consumption of produce by consumers has been attributed to perceived health benefits of postharvest produce. Pathogen control is crucial because periodic occurrences and contamination of tomato and leafy greens have exacerbated food safety risks for consumers. We investigated the effects of temperatures (5 and 25 °C), storage time (30 min and 24 h) for inactivation of Listeria monocytogenes, Salmonella enterica and Escherichia coli O157:H7 by sophorolipid (SL‐p) produced fermentatively using palmitic acid as a co‐substrate at different concentrations in vitro. Reduction in pathogenic bacteria on grape tomato by SL‐p, sanitiser (Lovit) and combinations of SL‐p and sanitiser was determined. Temperature and storage time significantly (P < 0.05) affected pathogen inactivations by SL‐p as pathogen reductions were greater at 25 °C and 24 h than at 5 °C and 30 min of storage. L. monocytogenes was the most sensitive to SL‐p treatment as reductions of 5 log relative to untreated controls were attained at 0.12% of SL‐p. Significant reductions in S. enterica (1.91–3.85 logs) and E. coli O157:H7 (0.87–4.09 logs) were recorded at 2–5% of SL‐p. Lower populations of Salmonella and E. coli O157:H7 were inactivated than L. monocytogenes. On grape tomato, pathogen populations inactivated increased at higher SL‐p levels at 25 °C. Sanitiser and sanitiser + SL‐p reduced bacterial populations on tomato by 5.29–5.76 logs and 0.71–3.3.66 logs, respectively. These results imply the interactions of temperature, storage time and SL‐p significantly (P < 0.05) affected pathogen strain reductions. The combination of SL‐p with sanitiser led to synergistic effect on E. coli O157:H7, but not L. monocytogenes and S. enterica. 相似文献
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Riya Chakraborty Arjun Dey Anoop Kumar Mukhopadhyay 《Metallurgical and Materials Transactions A》2010,41(5):1301-1312
To understand how hardness, the key design parameter for applications of brittle solids such as glass concerning contact deformation,
is affected by loading rate variation, nanoindentation with a Berkovich tip was used to measure the nanohardness of a 330-μm-thick soda-lime-silica glass as a function of loading rate (1 to 1000 mN·s−1). The results showed for the very first time that, with variations in the loading rate, there was a 6 to 9 pct increase in
the nanohardness of glass up to a threshold loading rate (TLR), whereafter it did not appreciably increase with further increase
in loading rate. Further, the nanohardness data showed an indentation size effect (ISE) that obeyed the Meyer’s law. These
observations were explained in terms of a strong shear stress component developed just beneath the nanoindenter and the related
shear-induced deformation processes at local microstructural scale weak links. The significant or insignificant presence of
shear-induced serrations in load depth plots and corresponding scanning electron microscopic evidence of a strong or mild
presence of shear deformation bands in and around the nanoindentation cavity supported such a rationalization. Finally, a
qualitative picture was developed for different deformation processes induced at various loading rates in glass. 相似文献
49.
Arjun DeySamit Kumar Nandi Biswanath Kundu Chandrasekhar KumarPrasenjit Mukherjee Subhasis RoyAnoop Kumar Mukhopadhyay Mithlesh Kumar SinhaDebabrata Basu 《Ceramics International》2011,37(4):1377-1391
Here we report a comparative study of the healing kinetics of surgically created artificial defects in the tibia of New Zealand white rabbits. Comparison of the healing kinetics was made for uncoated conventional SS316L intramedullary pins, and the same pins with microplasma sprayed (MIPS) pure hydroxyapatite (HAp) and beta-tri calcium phosphate (β-TCP) coatings. After thorough material characterizations including XRD, FTIR, SEM, etc., MIPS coated pins were implanted to such animals. Serum biochemistry, radiology and fluorochrome labelling were used to evaluate the comparative healing kinetics of these implants in vivo. In comparison to those of the uncoated pins, the pins coated with both MIPS HAp and β-TCP showed significant increment of alkaline phosphatase up to 15th postoperative day, insignificant changes in serum phosphorus and calcium with uneventful healing of bone defect. There was development of Havarsian canals and well-defined peripherally placed osteoblasts along with evidence of angiogenesis and comparatively more new bone formation in the defect site. On a comparative scale, the performance of the β-TCP coated intramedullary pins was much better than that of the pure HAp coated pins than the uncoated intramedullary pins. 相似文献
50.
In this contribution, we report the analysis and interpretation of the mechanical property measurements for a new class of SiAlON ceramic. The hardness and indentation fracture toughness were measured on the hot pressed Ba-doped S-SiAlON ceramic using Vickers indentation at varying loads (up to 300 N). An important observation was that all the investigated S-SiAlON exhibited the characteristic rising R-curve behavior with a maximum toughness of up to 10–12 MPa m1/2 for ceramics, hot pressed both at 1700 and 1750 °C. Crack deflection by large elongated S-phase grains and crack bridging by β-Si3N4 needles has been found to be the major toughening mechanisms for the observed high toughness. Theoretical estimates, using a toughening model based on crack bridging and deflection by platelet shaped ‘S’-phase grains and β-Si3N4 needles, reveal the interfacial friction of around 200 MPa. Careful analysis of the indentation data reveals the average (apparent) hardness modestly increases with indent load in all S-SiAlON samples, with more significant effect for S-SiAlON, hot pressed at 1600 °C. This effect has been analyzed in the light of the established model of ‘indentation-induced cracking’ phenomenon. Our experimental results suggest that a modest combination of average hardness of 15 GPa and indentation toughness of around 12 MPa m1/2 could be achieved in Ba-S-SiAlON ceramic and further improvement requires microstructural tailoring. 相似文献