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211.
Anthony J. Sadar 《Science & Education》2018,27(1-2):233-235
212.
Donghui Zhang 《Frontiers of Education in China》2018,13(3):448-450
213.
Heidi Omdal 《Journal of Educational Change》2018,19(1):103-129
The being together intervention intends to raise teacher capacity in Norwegian Early Childhood Education and Care (ECEC) institutions and promote social and emotional development in preschoolers by implementing an authoritative (warm and predictable) adult style in the institution. An authoritative adult balances between building up high quality interactions with children, while at the same time having a predictable structure with clear norms and social expectations in the learning environment. The purpose of this study was to investigate what helped the ECEC institutions to successfully implement the program principles and core components, and what were the challenges. The staff groups of seven Norwegian ECEC institutions in different municipalities who took part in the innovation were interviewed at the beginning and before the end of the first year of implementation. Data analysis identified five success criteria in the implementation process; strong commitment to the authoritative adult style, strong focus on the implementation process, advanced support systems, highly involved leaders, and a collective orientation. These elements resulted in a shared vision and an academically grounded practice in the ECEC institutions. Staff members without formal professional training and a lack of written documentation in the ECEC institutions should be given more consideration in further improvement of the capacity building. 相似文献
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217.
CHEN Xiao-fei ZOU Xue-cheng LIN Shuang-xi LIU Zheng-lin JIN Hai 《浙江大学学报(A卷英文版)》2007,8(8):1346-1350
An integrated laser diode driver(LDD) driving an edge-emitting laser diode was designed and fabricated by 0.35 μm BiCMOS technology. This paper proposes a scheme which combines the automatic power control loop and temperature com-pensation for modulation current in order to maintain constant extinction ratio and average optical power. To implement tem-perature compensation for modulation current,a novel circuit which generates a PTAT current by using the injecting base current of a bipolar transistor in saturation region,and alternates the amplifier feedback loop(closed or not) to control the state of the current path is presented. Simulation results showed that programmed by choice of external resistors,the IC can provide modu-lation current from 5 mA to 85 mA with temperature compensation adjustments and independent bias current from 4 mA to 100 mA. Optical test results showed that clear eye-diagrams can be obtained at 155 Mbps,with the output optical power being nearly constant,and the variation of extinction ratio being lower than 0.7 dB. 相似文献
218.
WANG Chi-yu ZOU Jun FU Xin YANG Hua-yong 《浙江大学学报(A卷英文版)》2007,8(9):1422-1428
The characteristics of the fluidic flowmeter,which is a combination of impinged concave wall and bistable fluid amplifier,is investigated by experimental studies and numerical simulations. The numerical approaches are utilized to examine the time dependent flow field and pressure field inside the proposed flowmeter. The effect of varying structural parameters on flow characteristics of the proposed fluidic flowmeter is investigated by computational simulations for the optimization. Both the simulation and experimental results disclose that the hydrodynamic vibration,with the same intensity,frequency and 180° phase shift,occurs at axisymmetric points in the feedback channel of the fluidic flowmeter. Using the structural combination of impinged concave wall and bistable fluid amplifier and differential signal processing technique,a novel fluidic flowmeter with excellent immunity and improved sensibility is developed. 相似文献
219.
CHEN Zu-yu 《浙江大学学报(A卷英文版)》2007,8(11):1712-1724
The solution of a slope stability problem can be approached by its least upper-bound and maximum lower-bound with high accuracy. The limit equilibrium methods that employ vertical slices imply a lower bound of the factor of safety. It has been successfully extended to the area of active earth pressure analysis that accounts for different input of locations of earth pressure applications. Those methods that employ slices with inclined interfaces give an upper-bound approach to the stability analysis. It enjoys a sound mechanical background and is able to provide accurate solutions of soil plasticity. It has been successfully extended to the area of bearing capacity analysis in which various empirical coefficients are no longer necessary. The 3D upper- and lower-bound methods under this framework have been made possible and show great potential for solving various engineering problems. 相似文献
220.
TOPCU Ilker Bekir BILIR Turhan 《浙江大学学报(A卷英文版)》2007,8(11):1725-1730
In recent years, the usages of by-products and wastes in industry have become more important. The importance of the sustainable development is also of increasing. The utilizations of wastes, as mineral admixture or fine aggregate, reduce the consumption of the natural resources and improve the durability of concrete. In this study, the effect of the fineness on the high temperature and sulphate resistances of concrete mortar specimens, produced with ground granulated blast-furnace slag (GBFS) replacing cement, is investigated. The compressive and flexural strength test results for all series related to durability effects, exposing temperature and solutions, exposure times for these durability effects, slag content and fineness are discussed. Conse- quently, the optimum slag contents are determined for producing the sulphate and high temperature resistant mortars. 相似文献