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31.
Moacir Godinho Filho Antonio Gilberto Marchesini Jan Riezebos Nico Vandaele Gilberto Miller Devós Ganga 《国际生产研究杂志》2017,55(17):4891-4911
The main goal of this research is to identify whether companies that have implemented the Quick Response Manufacturing (QRM) approach have full knowledge of the QRM principles or have merely applied the elements (principles and tools) that have a close relationship with Lean Manufacturing. Based on a review of the literature regarding the QRM principles, an exploratory survey was conducted for over 20 manufacturing companies from Brazil, Europe and the USA that operate in an Engineer or Make to Order environment system and explicitly have conducted QRM journeys. The results of the present study show that (i) the surveyed companies have difficulty knowing and applying some of the exclusive elements of this approach, even if they started implementing QRM several years ago; (ii) the surveyed companies’ knowledge degree over QRM exclusive elements is apparently higher among US-based companies due to better trained employees and better dissemination and awareness of the QRM exclusive elements; and (iii) a mentality based on productivity, low costs and due date delivery was identified as the main barrier for companies to achieve a higher knowledge degree regarding QRM. 相似文献
32.
Wireless Personal Communications - Recent trends and clustered technology in the IT industries create usage of various hand-held computing devices like mobile phones, digitizer, modem, tablets etc.... 相似文献
33.
Representation and reasoning of actions is a wide spread area in the domain of Artificial Intelligence. The representation involves natural language instructions, which are based on the linguistic concepts and the reasoning methodology deals with the logical structures. In the computational domain, several theories pertaining to the state-space approach have been proposed to represent and reason out actions. Considering these aspects, this paper provides an account of work from the viewpoint of linguistics, logic and action representation formalisms. Based on this study, this paper then proposes a seven axes categorization scheme, that can be used to compare and analyze different theories. 相似文献
34.
Swamy Savvemala Girimanchanaika Dukanya Dukanya Ananda Swamynayaka Divya Maldepalli Govindachar Mahendra Madegowda Ganga Periyasamy Kanchugarakoppal Subbegowda Rangappa Vijay Pandey Peter E. Lobie Basappa Basappa 《International journal of molecular sciences》2021,22(20)
The design and development of a small molecule named NPB [3-{(4(2,3-dichlorophenyl)piperazin-1-yl}{2-hydroxyphenyl)methyl}-N-cyclopentylbenzamide], which specifically inhibited the phosphorylation of BAD at Ser99 in human carcinoma cells has been previously reported. Herein, the synthesis, characterization, and effect on cancer cell viability of NPB analogs, and the single-crystal X-ray crystallographic studies of an example compound (4r), which was grown via slow-solvent evaporation technique is reported. Screening for loss of viability in mammary carcinoma cells revealed that compounds such as 2[(4(2,3-dichlorophenyl)piperazin-1-yl][naphthalen-1-yl]methyl)phenol (4e), 5[(4(2,3-dichlorophenyl)piperazin-1-yl][2-hydroxyphenyl)methyl)uran-2-carbaldehyde (4f), 3[(2-hydroxyphenyl][4(p-tolyl)piperazin-1-yl)methyl)benzaldehyde (4i), and NPB inhibited the viability of MCF-7 cells with IC50 values of 5.90, 3.11, 7.68, and 6.5 µM, respectively. The loss of cell viability was enhanced by the NPB analogs synthesized by adding newer rings such as naphthalene and furan-2-carbaldehyde in place of N-cyclopentyl-benzamide of NPB. Furthermore, these compounds decreased Ser99 phosphorylation of hBAD. Additional in silico density functional theory calculations suggested possibilities for other analogs of NPB that may be more suitable for further development. 相似文献
35.
Proper design of helium systems with large number of components and involved configurations such as helium liquefiers/refrigerators requires the use of tools like process simulators. The accuracy of the simulation results, to a great extent, depends on the accuracy of property data. For computation of thermodynamic properties of helium, the 32-parameter MBWR equation of state proposed by McCarty and Arp [1] is widely used. However, it is computationally involved, makes the simulation process more time-consuming and sometimes leads to computational difficulties such as numerical oscillations, divergence in solution especially, when the process operates over a wide thermodynamic region and is constituted of many components. Substituting MBWR EOS by simpler equations of state (EOS(s)) at selected thermodynamic planes, where the simpler EOS(s) have the similar accuracy as that of MBWR EOS may enhance ease of computation. In the present paper, the methodology to implement this concept has been elucidated with examples of steady state and dynamic simulation of helium liquefier/refrigerator based on Collins cycle. The above concept can be applied to thermodynamic analysis of other process cycles where computation of fluid property is involved. 相似文献
36.
In this work, the presence of biogenic amines (BAs) was correlated with the type of wine grape culture (traditional or organic) and their concentration in the different stages of winemaking (must, alcoholic fermentation [AF] and malolactic fermentation [MLF]). The formation of BA occurred mainly during MLF in which the percentages for putrescine, cadaverine, phenylethylamine, histamine, and tyramine were 100%, 70%, 13%, 61%, and 44% for the wines produced with traditional grapes and 100%, 94%, 25%, 88%, and 13% for the wines produced with organic grapes, respectively. In general, these latter wines exhibited a lower concentration of total amines. The principal component analysis and partial least-square discriminate analysis indicated that the generation of BA has a certain behavioral pattern in the wines analyzed, which is associated with the different stages of wine production and with the type of culture (traditional or organic) used in the wine grapes. Practical Application: Chemometrics tools can be useful as a method of characterization and classification in a global overview of the process variables involved in the development of toxic chemicals in foods, such as the production of BA in wine. 相似文献
37.
Rajavel Vijayakumar Murugesan Rajkumar Parthasarathi Sridhar Sethuraman Pitchumani 《Journal of Applied Electrochemistry》2012,42(5):319-324
The effect of the anode and cathode flow field depths on the performance of a single cell Direct methanol fuel cell (DMFC)
of 45 cm2 active area were experimentally investigated. Double serpentine flow fields (DSFFs) with varying channel depth namely, 0.2,
0.4, 0.6, 0.8, and 1 mm but with fixed channel and rib width each of 1 mm on both anode and cathode were designed, fabricated,
and tested. The experimental study involved measurement of pressure drops across anode and cathode flow field plates, polarization,
and carbon dioxide concentration measurements at various current densities. The mass transport at both anode and cathode were
found to increase with increase in pressure drop across the flow field on account of reduced channel depth from 1.0 to 0.4 mm
at all current densities. However, further decrease to a channel depth of 0.2 mm was found to be counter-productive with different
phenomena operating on either side viz., increased CO2 slug length on the anode flow channel and increased methanol crossover on the cathode side. Hence, the maximum performance
for DMFCs was observed for a channel depth of 0.4 mm on anode and cathode flow fields. A decrease in flow field channel depth
at cathode was found to increase the methanol crossover due to convective mass transfer effect. 相似文献
38.
Parthasarathi Bera Michael Rajamathi M. S. Hegde P. Vishnu Kamath 《Bulletin of Materials Science》2000,23(2):141-145
Mass spectrometric analysis of gases evolved during thermal decomposition of divalent metal hydroxides, hydroxysalts and hydrotalcites
show that all these compounds undergo dehydration in the temperature range 30 <T < 220°C followed by decomposition at temperatures above 250°C. The latter step involves simultaneous deanation and dehydroxylation
of the layers. Our observations conclusively prove that alternative mechanisms which envisage CO2 evolution due to deanation at lower temperatures proposed by Kanezaki to be wrong. 相似文献
39.
S. K. Choudhury Ganga Raju 《International Journal of Machine Tools and Manufacture》2000,40(6):887-898
This paper presents the effects of spindle rotational speed and feed rate on the crater wear along the lip of a drill. A theoretical model has been developed to correlate the cutting parameters with crater wear through the cutting forces. A series of experiments was conducted to study the performance of the drilling process in terms of drill wear and the effects of cutting parameters on it. The experiments were planned using the concept of a central composite rotatable design for three factors. An empirical relationship between crater wear and the cutting parameters at any point on the lip has been developed. The correlation coefficient between the experimentally measured and empirically calculated values of crater wear was found to be 0.9821. Crater wear has been recommended for acceptance as a performance index owing to the relative ease with which it can be measured and the fact that, at higher speeds, crater wear is more significant than flank wear. Close relationships between the experimental and theoretical results were found. 相似文献
40.
Kamalesh Pal Amitava Mukherjee Md. Motin Seikh Parthasarathi Bera Arup Gayen 《Ceramics International》2021,47(10):14798-14808
Synthesis of nanocrystalline pristine and Mn-doped calcium copper titanate quadruple perovskites, CaCu3?xMnxTi4?xMnxO12 (x = 0, 0.5, and 1.0) by modified citrate solution combustion method has been reported. Powder X-ray diffraction patterns attest the phase purity of the perovskite materials. Average particle sizes of all the materials obtained from the Scherrer's formula are in the range of 55–70 nm. The specific surface areas for all the perovskites obtained from BET isotherms are found to be low as expected for the condensed oxide systems and fall in the range of 13–17 m2 g?1. Transmission electron microscopy studies show a reduction in particle size of CaCu3Ti4O12 with increase in Mn doping. Ca and Ti are present in +2 and +4 oxidation states in all the materials as demonstrated by X-ray photoelectron spectroscopy analyses. Cu2+ gets reduced in CaCu3Ti4O12 with higher Mn content. Mn is observed to be present only in +3 oxidation state. All the materials have been examined to be active in CO oxidation as well as H2 production from methanol steam reforming. CaCu3Ti4O12 with ~14 at.% Mn is found to show best catalytic activities among these materials. A comprehensive analysis of the catalytic activities of these perovskites toward CO oxidation and H2 production from MSR reveal the cooperative activity of copper-manganese in the doped perovskites and it is more effective at lower manganese content. 相似文献