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71.
The mobility of African students beyond national territories has become common worldwide. However, the underlying reasons motivating students to leave their countries of origin in pursuit of higher education in other developing nations and why these factors are important have not been fully explored. This study attempts to explore why and how African students travel to the United Arab Emirates for higher education. A push-pull factor theory of the international student’s choice of destination is developed to identify factors influencing the choices made by these students. The analytic hierarchy process is used to examine the relative importance of these factors. The findings of this quantitative study indicate that learning environment and geographic proximity are the two most important factors for African students, while other factors have a moderate impact. The findings contribute to a deeper and more comprehensive understanding of the needs and choices of existing and potential students from this continent, with a view to applying a segmentation approach to attract these students. 相似文献
72.
This paper presents a class of time-frequency distributions (TFDs) characterized by time-lag kernels which are functions of time only. If the parameters of the time-only kernels are properly chosen, their corresponding TFDs, the T-distributions, are more efficient than their two-dimensional counterparts in terms of cross-terms suppression while keeping a high-energy concentration (resolution) around the IF law of non-stationary signals. The proposed class is a subclass of Cohen's Class of quadratic TFDs. We have shown that separable time-lag kernels should be lag-independent (or time-only) for best resolution. In addition, non-parametric amplitude estimation is possible directly from the T-distributions in case of FM signals, a property that is not verified by other TFDs. Two examples of the T-distributions are given and their performance is compared to other TFDs with numerical examples using synthetic and real-life signals. 相似文献
73.
S. F. Shaukat Ph. D. Ya-Ming Dong Ph. D. M. Hussain R. Farooq Guang-Yuan Li 《上海大学学报(英文版)》2002,6(1):45-49
Up-conversion processes for the blue, green and red emissions were found two-photon phenomenon, known as the cooperative phenomenon.
This phenomenon was assisted by Nd3+ → Yb3+ → Ho3+ energy transfer. The strong green emission due to the Ho3+ : (5F4, 5S2)→ 5I8 transitions was observed in Nd3+-Ho3+ co-doped ZrF4-based fluoride glasses under 800 nm excitation. As an attempt to enhance Ho3+ up-conversion luminescences in the Nd3+ – Ho3+ co-doped ZrF4-based glasses, Yb3+ ions were added to the glasses. As a result it was found that, in 800 nm excitation of 60 ZrF4. 30BaF2. (8-x)LaF3. lNdF3. xYbF3. 1HoF3 glasses (x=0 to 7), sensitized up-conversion luminescences are observed at around 490 nm (blue), 545 nm (green), and 650 nm (red), which
correspond to the Ho3+ : 5F3 → 5I8, ( 5F4, 5S2)→5I8 and 5F5→ 5I8 transitions respectively. The intensities of the green and red emissions in a 3 mol % YbF3-containing glass were about 50 times stronger than those glasses without YbF3. This is based on sensitization due to Yb3+ ions. In particular, the green emission was extremely strong and the Nd3+-Yb3+-Ho3+ co-doped ZrF4-based glasses have a high possibility of realizing a green up-conversion laser glass. In this paper the up-conversion mechanism
in the glasses is discussed in detail. 相似文献
74.
75.
B. Shailaja G. Jagadeesh Tajamul Hussain M. P. J. S. Anandaraj 《Indian journal of clinical biochemistry : IJCB》1996,11(2):165-167
With a view to gain an insight into the regulation of calcium activated neutral protease by its endogenous inhibitor, the inhibitor was quantitated in platelets and lymphocytes of Duchenne muscular dystrophy patients and controls by dot immunoblot procedure using polyclonal antibodies against the inhibitor. A two fold increase in inhibitor levels was observed in lymphocytes but no significant increase in inhibitor levels in platelets from Duchenne muscular dystrophy. These results suggest that different regulatory mechanisms of modulation of CANP operate in these two cell types in Duchenne muscular dystrophy. 相似文献
76.
P. Aruna Prabhavathi Tajamul Hussain G. N. Mallikarjuna Rao MP JS Anandaraj 《Indian journal of clinical biochemistry : IJCB》2002,17(1):94-98
The efficacy of two intragenic polymorphic markers of factor VIII gene has been examined in Andhra Pradesh population with
a view to confirm/revise the strategy for carrier detection that would be precise and economical. The haemophilia A carrier
was detected using Bcl I and Xba I polymorphic sites in intron 18 and 22 respectively. The cumulative efficiency of these
two sites for detection of carriers is 100% since all 15 families tested were informative for one of these polymorphisms,
thus confirming their usefulness for factor VIII gene mutations found in Andhra Pradesh. 相似文献
77.
A.V. Balakrishnan Amjad M. Tuffaha Iylene Patino Oleg Melnikov 《Journal of The Franklin Institute》2014
We present a methodology for calculating flutter speeds of a high aspect ratio flying wing articulated with point masses in inviscid air flow. This highly flexible wing configuration typically models a HALE (High Altitude Long Endurance) UAV (Unmanned Aerial Vehicle) type aircraft. To demonstrate the procedure, we perform flutter analysis on an actual articulated wing model and we investigate the dependence of the flutter speed on the number of loads mounted onto the structure and the number of panels comprising the flying wing for both varying and constant span. The results show that the flutter speed decreases as more panels and point masses are incorporated into the flying wing. On the other hand, the number of point masses mounted onto the structure has a small effect on the flutter speed if the wing span is kept constant. 相似文献
78.
Immunogenicity of formaldehyde and binary ethylenimine inactivated infectious bursal disease virus in broiler chicks 总被引:2,自引:2,他引:0
Habib M Hussain I Irshad H Yang ZZ Shuai JB Chen N 《Journal of Zhejiang University. Science. B》2006,7(8):660-664
Infectious bursal disease virus (IBDV) was inactivated by two different chemicals-formaldehyde and binary ethylenimine (BEI). Formaldehyde was used at 0. 1% and 0.2%, while BEI was used at concentrations of 0.001 and 0.002 mol/L. These four vaccines were tested for their efficiency in generating humoral immune response in different groups of broiler chicks. Both BEI-inactivated vaccines gave relatively higher antibody titers and were almost twice as efficient as formaldehyde-inactivated ones. 相似文献