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101.
An understanding of human factors and ergonomics facilitates the design of artefacts, tasks and environments that fulfil their users’ physical and cognitive requirements. Research in these fields furthers the goal of efficiently accommodating the desired percentage of user populations through enhanced awareness and modelling of human variability. Design for sustainability (DfS) allows for these concepts to be leveraged in the broader context of designing to minimise negative impacts on the environment. This paper focuses on anthropometry and proposes three ways in which its consideration is relevant to DfS: reducing raw material consumption, increasing usage lifetimes and ethical human resource considerations. This is demonstrated through the application of anthropometry synthesis, virtual fitting, and sizing and adjustability allocation methods in the design of an industrial workstation seat for use in five distinct global populations. This work highlights the importance of and opportunities for using ergonomic design principles in DfS efforts. Practitioner Summary: This research demonstrates the relevance of some anthropometry-based ergonomics concepts to the field of design for sustainability. A global design case study leverages human variability considerations in furthering three sustainable design goals: reducing raw material consumption, increasing usage lifetimes and incorporating ethical human resource considerations in design. 相似文献
102.
We report the fluorescence properties of Sm3+-doped lead telluroborate glasses of composition PbF2.TeO2.H3BO3.Sm2O3 as a function of Sm3+ concentration. A Judd-Ofelt scheme was used to determine the intensity parameters and radiative properties of Sm3+ ion. The emission and decay measurements were carried out at 402 nm excitation. Beyond 1.0 mol% Sm3+ concentration, the luminescence quenching is observed. The decay curves of 4G5/2 level are well fitted to a single exponential function. The evaluated radiative properties suggest that the 4G5/2 → 6H7/2 transition is responsible for reddish-orange luminescence which might be used in the development of visible lasers. 相似文献
103.
104.
The simulation model of a transcritical CO2 heat pump dryer presented in Part 1 has been first validated with available experimental data in this part and then used to simulate the heat pump dryer to study the variation of performance parameters such as heating COP, moisture extraction rate, and specific moisture extraction rate. The validation with experimental data shows that the model slightly over predicts the system performance. The possible reasons for the difference between experimental and numerical results are explained. Simulation results show the effect of key operating parameters such as bypass air ratio, re-circulation air ratio, dryer efficiency, ambient condition (temperature and relative humidity), and air mass flow rate. Results show that unlike bypass air ratio and ambient relative humidity, the effect of dryer efficiency, recirculation air ratio, ambient temperature, and air mass flow rate are very significant as far as the system performance is concerned. 相似文献
105.
106.
S. Sathish S. Chaterjee O. N. Awasthi E. S. R. Gopal 《Journal of Low Temperature Physics》1986,63(5-6):423-429
The electron-electron scattering contribution to the ultrasonic attenuation in potassium at low temperatures is evaluated using the Landau Fermi liquid theory. The scattering function is evaluated using the approximation suggested by MacDonald and Geldart. The results are compared with theoretically evaluated electron-phonon scattering contributions. The results show that the electron-electron scattering contribution is of the same order as the electron-phonon scattering contribution in the 2–5 K range. Below 2 K the electron-electron scattering predominates. 相似文献
107.
Anil Kumar Mandeep Kaur Rajeev Kumar Pinaki Ranjan Sengupta Vasantha Raman Gopal Bhatia Kedar Nath Sood 《Journal of Materials Science》2010,45(5):1393-1400
Carbon–copper composites with varying copper to carbon ratio of 0.66–1.5 (by weight) were developed from coal-tar-pitch-derived
green coke (as such or modified with natural graphite) as carbon source and electrolytic grade copper powder at different
heat treatment temperatures (HTTs) of 1000–1400 °C. The physical, mechanical, and electrical properties differ depending upon
the HTT and also on copper to carbon ratio (Cu/C). The composites prepared at HTT of 1100 °C having Cu/C ratio of 0.66 and
0.9 exhibited a high bending strength of 150 and 140 MPa, bulk density of 2.63 and 2.81 gm/cm3, electrical resistivity of 1.6 and 0.96 m Ω cm and shore hardness of 88 and 84, respectively, in spite of well-known inadequate
wettability between copper and carbon. Increasing the temperature from 1100 °C for processing of the composites deteriorated
the properties mainly due to the loss of copper through melting above 1100 °C as revealed by X-ray, scanning electron microscopy,
thermal analysis and EDAX studies. 相似文献
108.
A variety of iron-metallated functional porphyrins have been synthesized and their catalytic activity to oxidize polycyclic aromatic hydrocarbons, (PAHs) using hydrogen peroxide as oxidant was investigated. It was found that iron-metallated porphyrins bearing strong electronegative groups at β-pyrrolic positions show an exceptionally high catalytic efficiency. 相似文献
109.
MP Fried J Kleefield H Gopal E Reardon BT Ho FA Kuhn 《Canadian Metallurgical Quarterly》1997,107(5):594-601
Image-guided surgery has recently been described in the literature as a useful technology for improved functional endoscopic sinus surgery localization. Image-guided surgery yields accurate knowledge of the surgical field boundaries, allowing safer and more thorough sinus surgery. We have previously reviewed our initial experience with The InstaTrak System. This article presents a multicenter clinical study (n=55) that assesses the system's capability for localizing structures in critical surgical sites. The purpose of this paper is to present quantitative data on accuracy and performance. We describe several new advances including an automated registration technique that eliminates the redundant computed tomography scan, compensation for head movement, and the ability to use interchangeable instruments. 相似文献
110.
Assessment of depression in adolescents using the Center for Epidemiologic Studies Depression Scale.
Roberts Robert E.; Andrews Judy A.; Lewinsohn Peter M.; Hops Hyman 《Canadian Metallurgical Quarterly》1990,2(2):122
Operating characteristics of the Center for Epidemiologic Studies Depression Scale (CES-D) were examined by using data from 4 samples of students in Grades 9–12. The CES-D was found to have good internal consistency and test–retest reliability. Dimensionality was comparable to that found for adults. Structure varied little by order of assessment (Trial 1 of Trial 2), age, or gender. Salience of items, in terms of rank order of mean item scores, was remarkably similar to that reported for college and general adult samples. With the standard cutoff score of 16 or more, half of the high school students were classified as depressed. There was a pronounced gender effect, with proportionately more women reporting depressive symptoms across the 4 samples. Although it appears that the CES-D scale may be appropriate for use with adolescents, the issues of stability of scores over time, appropriate cutoff scores, and usefulness in detecting cases of clinical depression remain unresolved. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献