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231.
Educational reform in Singapore: from quantity to quality 总被引:1,自引:1,他引:0
Pak Tee Ng 《Educational Research for Policy and Practice》2008,7(1):5-15
In 2004, Prime Minister Lee called teachers to “teach less” so that students might “learn more”. In 2005, the Ministry of
Education clarified this philosophical statement to mean transforming learning from quantity to quality—“more quality and
less quantity” in education. This is in line with the national vision of ‘Thinking Schools, Learning Nation’. This policy
initiative, which began in 2004, is set to change the fundamental nature of education in Singapore. This article discusses
this initiative, its major implications for schools in Singapore and the challenges to be addressed in the implementation
of the policy. In particular, the article discusses the issues of understanding an engaged learning paradigm, establishing
signposts for the shift from quantity to quality and the difficulties of system-wide transformation. The challenge for schools
is to go beyond the form of the initiative to bring real, substantial and sustainable educational change through this movement. 相似文献
232.
Shen-Ping Xiao Hong-Hai Lian Kok Lay Teo Hong-Bing Zeng Xiao-Hu Zhang 《Journal of The Franklin Institute》2018,355(17):8857-8873
This paper discusses the problem of synchronization for delayed neural networks using sampled-data control. We introduce a new Lyapunov functional, called complete sampling-interval-dependent discontinuous Lyapunov functional, which can adequately capture sampling information on both intervals from to and from to . Based on this Lyapunov functional and an improved integral inequality, less conservative conditions are derived to ensure the stability of the synchronization error system, leading to the fact that the drive neural network is synchronized with the response neural network. The desired sampled-data controller is designed in terms of solutions to linear matrix inequalities. A numerical example is provided to demonstrate that the proposed approaches are effective and superior to some existing ones in the literature. 相似文献
233.
Chia Weng Boon Chee Wei Neo David Chew Chiat Ng Victor Chee Wee Ong 《浙江大学学报(A卷英文版)》2018,19(4):255-265
The design of rock support for a typical horseshoe shaped tunnel with considerations of it being excavated into a twin arch tunnel was studied using the distinct element method (DEM). Two different competent rock covers, i.e. 4 m and 7.5 m above the tunnel crown, were analysed. The results are relevant to the granitic geological unit in Singapore which has a weathering profile with rockhead found at some locations to be only 20–35 m below ground level and undulating, leaving limited rock cover for some sections along tunnels of similar depth. The verification of the adequacy of competent rock cover is important to ensure that the choice of ground support is suitable, particularly when the tunnel is excavated using the drill-and-blast method. In the opening geometry analysed in this study, a side drift is excavated adjacent to the first tunnel to create a twin arch opening. This creates a pillar between the openings during the intermediate construction stage. The influence of excavating the side drift on the support of the first opening was studied. We found that the bolt forces in the pillar approximately doubled during the excavation of the side drift, which may have been due to the rock joint inclinations and adopted strength parameters. This paper shows how DEM analyses may be used to complement conventional empirical rock mass classifications to design rock supports. Limitations of the pressure relaxation approach to model 3D effects in 2D are acknowledged. 相似文献
234.
Leo Ng Simon M. Rosalie Dorianne Sherry Wei Bing Loh Andreas M. Sjurseth Shrikant Iyengar 《Journal of sports sciences》2018,36(19):2210-2216
Research has revealed that field hockey drag flickers have greater odds of hip and lumbar injuries compared to non-drag flickers (DF). This study aimed to compare the biomechanics of a field hockey hit and a specialised field hockey drag flick. Eighteen male and seven female specialised hockey DF performed a hit and a drag flick in a motion analysis laboratory with an 18-camera three-dimensional motion analysis system and a calibrated multichannel force platform to examine differences in lower limb and lumbar kinematics and kinetics. Results revealed that drag flicks were performed with more of a forward lunge on the left lower limb resulting in significantly greater left ankle dorsiflexion, knee, hip and lumbar flexion (Ps<0.001) compared to a hit. Drag flicks were also performed with significantly greater lateral flexion (P < 0.002) and rotation of the lumbar spine (P < 0.006) compared to a hit. Differences in kinematics lead to greater shear, compression and tensile forces in multiple left lower limb and lumbar joints in the drag flick compared to the hit (P < 0.05). The biomechanical differences in drag flicks compared to a hit may have ramifications with respect to injury in field hockey drag flickers. 相似文献
235.
A microfluidic dynamic fluorescence-activated interface control system was developed for lab-on-a-chip applications. The system consists of a straight rectangular microchannel, a fluorescence excitation source, a detection sensor, a signal conversion circuit, and a high-voltage feedback system. Aqueous NaCl as conducting fluid and aqueous glycerol as nonconducting fluid were introduced to flow side by side into the straight rectangular microchannel. Fluorescent dye was added to the aqueous NaCl to work as a signal representing the interface position. Automatic control of the liquid interface was achieved by controlling the electroosmotic effect that exists only in the conducting fluid using a high-voltage feedback system. A LABVIEW program was developed to control the output of high-voltage power supply according the actual interface position, and then the interface position is modified as the output of high-voltage power supply. At last, the interface can be moved to the desired position automatically using this feedback system. The results show that the system presented in this paper can control an arbitrary interface location in real time. The effects of viscosity ratio, flow rates, and polarity of electric field were discussed. This technique can be extended to switch the sample flow and droplets automatically. 相似文献
236.
This paper investigates the phenomenon of Faradaic charging in ac electrokinetics. Faradaic reactions were suggested as a key effect responsible for the reversal of pumping direction in ac micropumps. However, this hypothesis has yet to be proven convincingly and directly. Here we present an ion detection strategy to determine the production of ions through Faradaic hydrolytic reactions originating from direct application of voltage to electrolytic solutions during ac electrokinetics. Experiments were performed with symmetrical planar electrodes aligned along a microfluidic channel. Fluorescein, a pH-dependent dye, was employed as the pH indicator for the detection of ion production. Images were captured for analysis at various voltage levels. From analyzing the fluorescence intensity and its distribution, it can be concluded that the production of ions from hydrolytic reactions takes place and increases with the ac voltage. The coefficient of deviation indicates a significant enhancement at ac voltage above 11 Vpp. Lastly, we demonstrate a strategy using dc-biased ac electrokinetics to achieve controllability in direction and magnitude of the net fluid flow in pumping application. 相似文献
237.
We used national data to study the longitudinal effects of several variables on choice of Holland (1997) social type college majors versus other majors. We examined these effects for four of the five major U.S. racial/ethnic groups, Asian/Pacific Islanders, Hispanics, Blacks, and Whites. Effects of mathematics scores and gender on choice of social majors were fairly consistent across racial/ethnic groups, whereas effects of reading scores and SES differed across racial/ethnic groups. Results for Whites were most consistent with Holland's theoretical formulations regarding the effects of variables on choice of social-type educational/occupational environments. 相似文献
238.
239.
240.
Ng’asike John Teria 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2019,65(1):19-46
International Review of Education - Despite setting high hopes on education, very few pastoral nomad children in Kenya transition from primary education to secondary education. This article argues... 相似文献