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31.
The present paper discusses the role of cabs and the presence of other men in the cab in manufacturing respectability for the unmarried women agents of call centers in India. The night shift, an intrinsic part of work, at call centers in India demands mobility and access to public space during nights for its women employees. The paper elaborates how the relation between gender and space is evolving in the backdrop of the presence of someone trusted, through a shift from private patriarchy to public patriarchy for the women agents while accessing the public space. The paper is based on a total of sixty-one qualitative interviews conducted with unmarried women call center employees and parents based in Gurgaon, India.  相似文献   
32.
The ability to select the larger of two quantities ranging from 1 to 5 (relative numerousness judgment [RNJ[) and the ability to select the larger of two pairs of quantities with each pair ranging from 1 to 8 (summation) were evaluated in young, middle-aged, and older adult orangutans (7 Pongo pygmaeus abelii and 2 Pongo pygmaeus pygmaeus). Summation accuracy and RNJ were similar to those of previous reports in apes; however, the pattern of age-related differences with regard to these tasks was different from that previously reported in gorillas. Older orangutans were less accurate than the young and middle-aged for RNJ, and summation accuracy was equivalent among age groups. Evidence was found to suggest that the young and middle-aged based their selection of the largest quantity pair on both quantities within each pair during the summation task. These results show a relationship between subject age and the quantitative abilities of adult orangutans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
33.
In this contribution we derive a computational Bayesian approach to NARMAX model identification. The identification algorithm exploits continuing advances in computational processing power to numerically obtain posterior distributions for both model structure and parameters via sampling methods. The main advantage of this approach over other NARMAX identification algorithms is that for the first time model uncertainty is characterised as a byproduct of the identification procedure. The algorithm is based on the reversible jump Markov chain Monte Carlo (RJMCMC) procedure. Key features of the approach are (i) sampling of unselected model terms for testing for inclusion in the model (the birth move), which encourages global searching of the model term space, (ii) sampling of previously selected model terms for testing for exclusion from the model—a naturally incorporated pruning step (the death move), which leads to model parsimony, and (iii) estimation of model and parameter distributions, which are naturally generated in the Bayesian framework. We present a numerical example to demonstrate the algorithm and a comparison with a forward regression method: the results show that the RJMCMC approach is competitive and gives useful additional information regarding uncertainty in both model parameters and structure.  相似文献   
34.
Low ambient concentrations of trace metals including Zn may limit phytoplankton productivity in the North American Great Lakes. The microalgae Chlorella sp. UTCC 522 (Chlorophyta) and Cyclotella sp. UTCC 520 (Heterokontophyta), indigenous to the Great Lakes, were assayed for their Zn requirement and the ability for Co and Cd to metabolically substitute for Zn under conditions in which Zn bioavailability was limiting cell growth. Bioassays were conducted in the laboratory using chemically defined media and the metal buffer EDTA to control the free-ion concentrations of Zn2+ (10−15.3−10−10 mol/L), Cd2+ (10−15.1−10−10 mol/L), and Co2+ (10−14−10−10 mol/L). Influence of the metals on the phytoplankton was measured by the effect on specific growth rate. Both microalgae required Zn and could use Co and Cd as Zn substitutes; Cd was used less-effectively, although to a greater extent by the diatom Cyclotella than by the chlorophyte, Chlorella. The observed ability of the phytoplankton to use Cd and Co as Zn substitutes suggests that microalgae play an important role in the geochemical cycling of Zn, Cd and Co in large lakes, and the mobilization of Cd in lake ecosystems impacted by pollution.  相似文献   
35.
One of the commercial challenges today in the gem industry is to quickly identify the origin of color in pink diamonds — natural, treated and synthetic by use of standard and advanced gemological instruments.An analytical technique that is used by many gem labs involves UV fluorescence. The principle factors in the technique are the excitation wavelengths and the emission spectra. No systematic study of fluorescence of pink natural diamonds, pink treated and pink synthetic diamonds has been undertaken. This study is mainly focused on using fluorescence techniques to characterize pink diamonds and to compile a reference library of emission spectra. Longwave (LW) and shortwave (SW) fluorescence of 365, 254 and 220 nm illumination were used in a custom built microscope with a fluorescence camera to record images and a spectrometer to record spectral data with which to establish a correlation with the cause of color.Other advanced instruments (CL imaging, UV–VIS–NIR, FTIR, PL spectroscopy and electrical conductance) were used to establish additional criteria for distinguishing natural, treated and synthetic pink diamonds and to find a correlation with the “EGL USA CIS (Cross-reference Identification System) fluorescence method”.  相似文献   
36.
The effect of alcohol on identification accuracy is potentially an important topic. This study examined the effects of alcohol consumption on identification accuracy from showups, the identification procedure most likely to be used by police with intoxicated witnesses. The blood alcohol level of people exposed to a target was measured. In the target-present showup condition, blood alcohol level was not significantly related to correct identification rate. In the target-absent showup condition, the higher the blood alcohol level, the more people were likely to make a false identification. Implications for law enforcement and future research directions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
37.
Gas leakage rate through reinforced concrete shear walls: Numerical study   总被引:6,自引:2,他引:4  
Unlined reinforced concrete shear walls are often used as ‘tertiary boundaries’ in the United States Department of Energy (DOE) to house dangerous gases. An unanticipated event, such as an earthquake, may cause gases stored inside the walls to disperse into the environment resulting in excess pollution. To address this concern, in this paper, a methodology to numerically predict the gas leakage rate through these shear walls under lateral loading conditions is proposed. This methodology involves finite element and flow rate analysis. Strain distributions are obtained from the finite element analysis, and then used to simulate the crack characteristics on the concrete specimen. The flow rate through the damaged concrete specimen is then estimated using flow rate formulas available from the literature. Results from an experimental specimen are used to evaluate the methodology, and particularly its robustness in the flow rate estimation.  相似文献   
38.
39.
We report transmittance and conductivity measurements of aluminum-doped zinc oxide films grown by atomic layer deposition. The results show that the films have 80–90% transmittance in the visible region and good transmittance in the infrared. To our knowledge, this is the first time that the transmittance of aluminum-doped zinc oxide is reported to extend beyond 2500–5000 nm. Following annealing, an optimal sheet resistance of 25 Ω/□ was obtained for a 575 nm thick film with a carrier density of 2.4 × 1020 cm?3 without compromising the transmittance in the visible regime.  相似文献   
40.
When developing an indicator to detect temperature heterogeneities in a high pressure (HP) vessel, the temperature sensitivity and the broadness of the application window have to be weighed against each other. In this study, the potential of a Bacillus amyloliquefaciens α-amylase (BAA)-based indicator for mild pasteurization conditions was evaluated. Solvent engineering was successfully used to reach two objectives: (i) to shift the pressure,temperature-stability of BAA in the HP pasteurization range; (ii) to differentiate the pressure,temperature-range of BAA inactivation from the pressure,temperature-range of inactivation of a previously developed Bacillus subtilis α-amylase (BSA)-based indicator system (1 g/L – 0.05 M MES pH 5.0), towards milder processing conditions. The BAA-system (0.1 g/L – 0.1 M MES pH 5.0) was kinetically calibrated and modeled under static conditions. As these model parameters were inadequate to predict the residual α-amylase activity of BAA under dynamic conditions correctly, parameters were determined under dynamic conditions and subsequently successfully validated on an independent dynamic data set. Based on the kinetic model and parameters valid under dynamic conditions, isorate contour plots for different inactivation levels were constructed, demonstrating clearly the different application windows of the BAA- and BSA-systems.  相似文献   
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