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71.
72.
A typical or conventional workstation for a repetitive drill press operation was evaluated and subsequently redesigned by incorporating the concepts and principles of work design and ergonomics. The production task comprised of drilling four holes on a prepared steel plate. A methods–time measurement (MTM) analysis was conducted to eliminate unnecessary motions and improve the necessary (work) motions involved in task performance. The specific features of the redesigned workstation were specially designed equipment (jig, fixture, etc.), a suitable adjustable chair, proper work height, a placement of tools/equipment within reach envelope, and a comprehensive operator training method. An experimental investigation was conducted to evaluate and test the redesigned workstation in terms of operator productivity (production quantity and quality output) and satisfaction. The increases in quantity (number of holes drilled) and quality (number of good holes drilled) output were 22 and 50%, respectively, for the redesigned workstation compared to the typical or conventional workstation. The high improvement in quality output (50%) could be attributed to the improved design of the jig and fixture and the comprehensive operator training method, which emphasizes the quality aspect of production output. The improvement in operator satisfaction (scores) were highly significant. This investigation has demonstrated the beneficial effect of a combined work design and ergonomics approach, especially for the redesign of a workstation for a repetitive drill press operation. © 2007 Wiley Periodicals, Inc. Hum Factors Man 17: 395–410, 2007. 相似文献
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74.
Long-period fibre gratings in specially designed birefringent few-mode fibres are used to demonstrate spectrally flat polarisers with bandwidths of 10 nm and polarisation extinction levels of 20 dB. This is enabled by the special dispersive properties of few-mode fibres, yielding fibre polarisers with performance approaching that of bulk-optic devices. 相似文献
75.
This study examines the role of ArginMax, a natural daily dietary supplement, on male sexual function. 25 subjects diagnosed with mild to moderate erectile dysfunction were evaluated over a 4-week period while on ArginMax. Of the 21 subjects that completed the study, 88.9% improved in ability to maintain erection during sexual intercourse and 75.0% improved in satisfaction with their overall sex life. No significant side effects were noted. 相似文献
76.
The classical stochastic analog of the deterministic linear system in engineering is the linear system driven by white noise. As the promise of artificial neural networks in modeling nonlinear systems continues to grow, the need for a stochastic analog with quantitative foundations for analysis and synthesis will increase. This paper presents recent work in this direction, examining recurrent neural nets (RNN driven by white noise. We examine the effect of noise on the typical continuous-time RNN model. First, we perform qualitative analysis establishing uniform boundedness of moments of the neuron states over time. To enable practical application, however, it is necessary to relate these properties to useful measures that can be estimated. We thus subsequently derive bias and variance measures for the noisy RNN with respect to the corresponding deterministic RNN. This has significant practical implications, since net design is nonminimal in the sense that several nets can solve the same problem. The results allow the user to evaluate given RNN for noise performance. The designer can use these results to constrain the design space so that the design satisfies performance specifications whenever possible. An example is provided using the measures derived in this paper to predetermine the best among several RNN designs for a given problem. 相似文献
77.
Kundu Abhijit Adhikari Saikat Das Arnima Kanjilal Maitreyi Ray Mukherjee Moumita 《Microsystem Technologies》2021,27(2):569-584
Microsystem Technologies - Photo-sensors are integral part of different bio-medical diagnostic equipment. Each type of bio-molecules possess unique spectral fingerprint in visible wavelength region... 相似文献
78.
Sinha Swati Shaw Siddharth Biswas Kunal De Debashis Das Samir Chandra Sarkar Angsuman Bandyopadhyay Jaya 《Microsystem Technologies》2021,27(11):4087-4100
Microsystem Technologies - Single-Walled Carbon Nanotubes (SWCNTs) are widely used as potential carriers in drug delivery systems. The objective of this work was to observe the effects of pristine,... 相似文献
79.
This article reports the design and development of high power, low cross‐polarization, and high efficiency circularly polarized microstrip patch array antenna at S‐band, proposed for Indian Regional Navigation Satellite System payload. A novel feeding mechanism for truncated corner square patch based on square coaxial line for broadband impedance matching is discussed. Sequential rotation scheme for axial ratio improvement in an array is implemented. High power handling margins in critical regions of square coaxial line for multipaction breakdown is brought out. Measured 19 dB return loss bandwidth of array antenna is 15.6%. Axial ratio of 0.78 dB over global coverage is achieved in the desired frequency band of operation. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2012. 相似文献
80.
Haris B?C G. Pradhan A. Misra S. R. M. Prasanna R. K. Das R. Sinha 《International Journal of Speech Technology》2012,15(4):441-453
In this paper we describe the collection and organization of the speaker recognition database in Indian scenario named as IITG Multivariability Speaker Recognition Database. The database contains speech from 451 speakers speaking English and other Indian languages both in conversational and read speech styles recorded using various sensors in parallel under different environmental conditions. The database is organized into four phases on the basis of different conditions employed for the recording. The results of the initial studies conducted on a speaker verification system exploring the impact of mismatch in training and test conditions using the collected data are also included. A copy of this database can be obtained from the authors by contacting them. 相似文献