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971.
972.
Mantak?YuenEmail author Patrick?S.?Y.?Lau Queenie?A.?Y.?Lee Norman?C.?Gysbers Raymond?M.?C.?Chan Ricci?W.?Fong Y.?B.?Chung Peter?M.?K.?Shea 《Asia Pacific Education Review》2012,13(1):55-63
This study explored the concept of school connectedness and the factors that may influence its development with a sample of
Chinese adolescents. Six focus groups involving 52 high school students were conducted using a set of predetermined discussion
topics. Results indicated that the students fully understood the notion of school connectedness and could identify a number
of key influences affecting its development. These factors could be grouped under several domains including teacher care,
peer relations, broader school relationships, school disciplinary policies and practices, activities within the school’s guidance
and counseling program, and opportunities for talent development. The students were also able to suggest practical strategies
that schools might introduce to enhance and strengthen students’ acquisition of connectedness to school. The implications
from the findings are discussed with particular reference to implementing comprehensive school guidance and counseling program
in Hong Kong. 相似文献
973.
Ali Balc? Murat ?zdemir ?i?dem Apayd?n Fatmanur ?zen 《Asia Pacific Education Review》2012,13(1):137-146
The aim of this study is to analyse organizational corruption and to determine its level of relation to attitude towards work,
work ethics and organizational culture. The data in study have been collected from 441 public high school teachers employed
in the central districts of Ankara in the school year of 2008–2009. Data have been collected through ‘Scale for Organizational
Corruption’, ‘Scale for Attitude towards Work’, ‘Scale for Work Ethics’ and ‘Scale for Organizational Culture’, all of which
were developed by the researchers in this study. Correlation and regression analysis techniques have been used in analysing
the data. It is concluded from the study that there is a significant, though at an average level, relation between organizational
corruption, organizational culture and work ethics and that there is a negative significant relation, though at a low level,
between organizational corruption and attitude towards work. It is also concluded that the variables for attitude towards
work, work ethics and organizational culture explain 38% of the variation in organizational corruption. 相似文献
974.
975.
976.
研究了范畴£中具有泛分解的态射 f pgq?关于对称态射,??的加权 Moore-Penrose 逆,并给出了其存在的充要条件及其表达式. 相似文献
977.
衡水市中小企业经过近30年的发展,取得了突破性的进展,已成为衡水经济发展的主导力量。但是与先进地区相比较,还存在着一定的差距,加快发展已成为当务之急。作者对此进行了探讨,提出来如下建议:大力发展产业集聚区;培育龙头企业;拓宽资金来源,破解融资瓶颈;优化发展环境;积极发展新兴产业。 相似文献
978.
A type of hollow cylinder joints connected with H-shaped beams is proposed for spatial structures. Based on von Mises yield
criterion and perfect elasto-plasticity model, a series of finite element models of the joints is established, in which the
effect of geometric nonlinearity is taken into account. Then mechanical behavior and load-carrying capacity of the joints
were investigated, which were subjected to axial load, in- and out-plane bending moments, and their combinations. The results
show that the ultimate loads of the joints are determined by the maximum displacement. Furthermore, the case of one joint
connected with multiple beams was discussed. Experiments on a set of typical full-scale joints were conducted to understand
the structural behavior and the failure mechanism of joint, and also to validate the finite element models. Finally, the practical
calculation method was established through finite elements analysis (FEA) results and numerical fitting. The results show
that the joints are more ductile and materially economical than welded hollow spherical joints, and the practical calculation
method can provide a reference for direct design and the revision of relevant design codes. 相似文献
979.
Al?Emran?IsmailEmail author Ahmad?Kamal?Ariffin Shahrum?Abdullah Mariyam?Jameelah?Ghazali Mohammed?Abdulrazzaq Ruslizam?Daud 《浙江大学学报(A卷英文版)》2012,13(1):1-8
This paper discusses stress intensity factor (SIF) calculations for surface cracks in round bars subjected to combined torsion
and bending loadings. Different crack aspect ratios, a/b, ranging from 0.0 to 1.2 and relative crack depths, a/D, ranging from 0.1 to 0.6 were considered. Since the loading was non-symmetrical for torsion loadings, a whole finite element
model was constructed. Then, the individual and combined bending and torsion loadings were remotely applied to the model.
The equivalent SIF method, F*EQ, was then used explicitly to combine the individual SIFs from the bending and torsion loadings. A comparison was then carried
out with the combined SIF, F*FE, obtained using the finite element analysis (FEA) under similar loadings. It was found that the equivalent SIF method successfully
predicted the combined SIF for Mode I. However, discrepancies between the results determined from the different approaches
occurred when F
III was involved. It was also noted that the predicted F*FE using FEA was higher than the F*EQ predicted through the equivalent SIF method due to the difference in crack face interactions. 相似文献
980.
Xiao-hong?Han Yu?Qiu Ying-jie?Xu Men-yuan?Zhao Qin?WangEmail author Guang-ming?Chen 《浙江大学学报(A卷英文版)》2012,13(2):132-139
In this paper, a new ternary non-azeotropic mixture of HFC-161/125/143a (0.15/0.45/0.40 in mass fraction), as a promising
mixed refrigerant to R404A, is presented. The ozone depletion potential (ODP) of the new refrigerant is zero and its basic
thermodynamic properties are similar to those of R404A, but its global warming potential (GWP) is much smaller than those
of R507A and R404A. Meanwhile, theoretical calculations show that, under the working condition I (the average evaporation
temperature: −23 °C, the average condensing temperature: 43 °C, the superheat temperature: 28 °C, the subcooling temperature:
5 °C), the volumetric refrigerating effect and specific refrigerating effect of the new mixture are 2.33% and 15.48% higher,
respectively, than those of R404A. The coefficient of performance (COP) of the new mixture is 5.19% higher than that of R404A
and the pressure ratio of the new mixture is 0.82% lower than that of R404A. Equally, under the working condition II (the
average evaporation temperature: −40 °C, the average condensing temperature: 35 °C, the superheating temperature: 30 °C, the
subcooling temperature: 5 °C), the volumetric refrigerating effect and specific refrigerating effect of the new mixture are
2.24% and 20.58% higher, respectively, than those of R404A. The COP of the new mixture is 4.60% higher than that of R404A
and the pressure ratio of the new mixture is similar to that of R404A. The performances of the new mixture and R404A are compared
in a vapor compressor refrigeration apparatus originally designed for R404A under several working conditions (condensing temperatures:
35–45 °C, evaporation temperatures: −40–−20 °C). Experimental results show that the new mixture can obtain a higher COP, by
6.3% to 12.1%, and a lower pressure ratio, by 1.8% to 6.6%, compared to R404A; although the discharge temperature of the new
mixture is slightly higher than that of R404A. The advantages of the new mixture will be further verified in the actual system. 相似文献