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71.
N. Chandra Shekhar K. Venkatasubbaiah N. R. Kandukuria 《European Journal of Engineering Education》2012,37(6):575-591
Measuring overall service quality (OSQ) is gaining prominence in higher education due to the increased competition among engineering education institutions (EEIs) and growing awareness about value for money among the public. Determination of OSQ on certain institutional aspects is done by various agencies throughout the world. Each system uses a different set of weighted indicators to measure the overall service quality of institutions. Five service quality factors, namely professionalism, integrated education, facilities, responsiveness and empathy are considered in the study. Trapezoidal fuzzy numbers are used to determine the aggregate weights of the factors to handle the vagueness present in the linguistic values of the stakeholders’ subjective opinions. Final weights of the factors are assessed by taking the distances of each factor between Fuzzy Positive Ideal Rating and Fuzzy Negative Ideal Rating. An illustrative study is presented to determine the OSQ of EEIs. The results help to focus on the factors which need immediate attention to enhance the quality of EEIs. 相似文献
72.
To elucidate a higher rate of premature cardiovascular disease (CVD) in Asian Indian descendants (Roma) in Slovakia, we investigated frequency distribution, correlates and relationship of lipoprotein(a) [Lp(a)] to family CVD risk factors in Roma children and their Caucasian neighbors. The study sample consisted of 607 healthy children aged 7–18 years (55% Roma, 48% male) as part of the biracial (Roma–Caucasian) Slovak Lipid Community Study. Overall, frequency distribution data of Lp(a) were highly skewed to low concentrations, with markedly higher Lp(a) levels in Roma than in Caucasian children (median and range, mg/dL: 14.5; 0–159.2 vs 6.2; 0–112.3, P < 0.001), regardless of age and gender. Lp(a) was positively correlated with apo B (0.159, P = 0.004) in Roma, and LDL cholesterol (0.170, P = 0.005) in Caucasian children. In addition, daily income of the family was negatively related with Lp(a) in Roma (−0.134, P = 0.036) while positively in Caucasians (0.136, P = 0.047). For both race groups, no significant association was found between Lp(a) and age, body mass index, mean arterial pressure, smoking, and physical activity. Also, no significant relationships were examined between serum Lp(a) levels >30 mg/dL in children and family CVD risk factors, except for diabetes mellitus in parents of Caucasian origin (OR 4.46; 95%CI: 1.23–16.20). In a multivariate analysis, daily income, LDL cholesterol or apo B explained ~7% of the variance of Lp(a). This study suggests a significantly higher serum Lp(a) levels in Roma than in Caucasian children and a small effect, in general, of relevant CVD risk factors on the variation of Lp(a) levels in childhood. 相似文献
73.
Benson KR 《Endeavour》2000,24(2):59-62
The modern discipline of biology was formed in the 20th century from roots deep in the natural-history tradition, which dates from Aristotle. Not surprisingly, therefore, ecology can also be traced to natural history, especially its 19th-century tradition emphasizing the adaptive nature of organisms to their environment. During the 20th century, ecology has developed and matured from pioneering work on successional stages to mathematically rich work on ecosystem energetics. By the end of the century, ecology has made a return to its natural-history heritage, emphasizing the importance of the integrity of ecosystems in considering human interactions with the environment. 相似文献
74.
R.M. Lichtenstein 《Journal of The Franklin Institute》1975,299(5):380
75.
Dynamic problems of axially moving materials as exemplified by strings in textile industry and band saws, belts and chains in mechanical machinery have recently received some attention (1–15). In the present study, the parametric resonance of an axially accelerated beam is investigated. The beam which has encastré ends is subjected to a periodic root force as shown in Fig. 1. The object of the investigation is to identify regions of instability of this system for various combinations of the excitation frequency and amplitude of the axial oscillations. 相似文献
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