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Science Bulletin 2005年第16期 141-144页

作者： ZHANG Tiebang1, CHEN Yungui1, FU Hao1, TENG Baohua2, TANG Yongbai1 & TU Mingjing1 1. School of Materials Science and Engineering, Sichuan University, Chengdu 610065, China 2. Department of Physics, National University of singapore, singapore 117542, Republic of singapore

The giant magnetocaloric effect Gd5Si2Ge2 alloy was prepared with 99wt% low purity commercial Gd. Pow-der XRD and magnetic measurements showed that the Gd5Si2Ge2 alloy annealed at 1200℃ for 1 h had a significant magnetic- crystallographic first order phase transition at about 270 K. The maximal magnetic entropy change is 17.55 J·kg?1·K?1 under a magnetic field change of 0―5 T. The distinct increase of magnetic entropy change belongs to the first-order phase transition from the orthorhombic Gd5Si4-type to the monoclinic Gd5Si2Ge2-type after high temperature heat-treatment.

关键词： magnetic refrigerant Gd5Si2Ge2 magnetocaloric effect.

A THIRD-ORDER BOUSSINESQ MODEL APPLIED TO NONLINEAR EVOLUTION OF SHALLOW-WATER WAVES

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Journal of Hydrodynamics 2000年第2期12卷 107-126页

作者： Zhang Ying long CCM MINDEF, Department of Mech. and Prod. Eng., National University of singapore, 10 Kent Ridge Crescent, singapore 119260 Zhu Song ping Department of Mathematics, the University of Wollongong, Wollongong, NSW 2522, Australia Natl Univ of singapore Singapore Singapore

The conventional Boussinesq model is extended to the third order in dispersion and nonlinearity. The new equations are shown to possess better linear dispersion characteristics. For the evolution of periodic waves over a constant depth, the computed wave envelops are spatially aperiodic and skew. The model is then applied to the study of wave focusing by a topographical lens and the results are compared with Whalin′s (1971) experimental data as well as some previous results from the conventional Boussinesq model. Encouragingly, improved agreement with Whalin′s experimental data is found. [WT5”HZ]

关键词： shallow water waves nonlinearity evolution third order Boussinesq model

Storage and Spatial Variation of Phosphorus in Paddy Soils of China

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Pedosphere 2009年第6期19卷 790-798页

作者： LIN Jin-Shi SHI Xue-Zheng LU Xi-Xi YU Dong-Sheng WANG Hong-Jie ZHAO Yong-Cun SUN Wei-Xia State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 2100(78 (China) Department of Geography National University of Singapore 119260 (Singapore) Graduate University of the Chinese Academy of Sciences Beijing 100049 (China) College of Resources and Environment Fujian Agriculture and Forestry University Fuzhou 350002 (China)

Due to the growing concern about the agricultural phosphorus (P) losses pollution, an in-depth understanding of P in paddy soils of China would be helpful in providing a national perspective of the environmental impact of P cycling and fertility on China's farms. In this study, we evaluated the P storage and the P density of paddy soils in China, characterized the spatial variations of P among the subgroups of paddy soils and soil regions in China, and evaluated the P data using GIS-based analysis, which included a newly compiled 1:1 000 000 digital soil map of China, and using 1 490 soil profiles. The available and total P densities of paddy soils were 6.7 and 698.5 g m -3 , respectively. Overall in China, the total P storage within 1 m of paddy soils was estimated to be 330.2 Tg. The P density of paddy soils varied substantially with subgroups due to the different soil water regimes such as groundwater table and soil drainage. The P availability in paddy soils, especially in surface layer, was higher in high temperature and precipitation areas. Further research is needed to examine more anthropogenic impact factors, such as increasing use of chemical fertilizer.

关键词： paddy soil database paddy soil subgroups phosphorus density phosphorus pool

Rate-oriented perceptual image coding using contrast-based quantization

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Chinese Optics Letters 2010年第4期8卷 381-383页

作者：余卫宇田菁 School of Electronic and Information Engineering South China University of Technology School of Electrical and Electronic Engineering Nanyang Technological University

A new image coding approach is proposed by controlling the quantization step via minimizing the perceptual distortions（in terms of image＇s contrast measurement）.The proposed method is a rate-oriented contrast-based approach,which is in contrast to the conventional quality-oriented contrast-based image *** algorithm achieves a higher perceptual quality performance against several methods developed previously.

关键词： Visual communication

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中国针灸 1995年第S2期15卷 228-229页

作者： Lee Kimleong(singapore Chinese physicians’ Association).

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Simulations of explosion-induced damage to underground rock chambers

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Journal of Rock Mechanics and Geotechnical Engineering 2011年第1期3卷 19-29页

作者： G.W.Ma1,H.Hao1,F.Wang2 1 School of Civil and Resource Engineering,The University of Western Australia,Crawley,WA 6009,Australia 2 Defense Science and Technology Agency,singapore,109679,singapore School of Civil and Resource Engineering The University of Western Australia Crawley WA 6009 Australia Defense Science and Technology Agency Singapore 109679 Singapore

A numerical approach is presented to study the explosion-induced pressure load on an underground rock chamber wall and its resultant damage to the rock *** simulations are carried out by using a modified version of the commercial software *** different criteria,i.e.a peak particle velocity (PPV) criterion,an effective strain (ES) criterion,and a damage criterion,are employed to examine the explosion-induced damaged zones of the underground rock *** results show that the charge chamber geometry,coupling condition and charge configuration affect significantly the dynamic pressure exerted on the rock chamber *** the chamber is *** inaccurate approximation of pressure boundary ignoring the influences of these factors would result in an erroneous prediction of damaged area and damage intensity of the charge *** PPV criterion yields the largest damaged zone while the ES criterion gives the smallest *** presented numerical simulation method is superior in consideration of the chamber geometry,loading density,coupling condition and rock *** predicted damage intensity of rock mass can be categorized quantitatively by an isotropic damage *** separation distance of adjacent chambers for a specific charge weight is also estimated.

关键词： underground explosion rock damage numerical simulation safe separation distance

China's Economy in 2007/2008:Coping with Problems of Runaway Growth

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China & World Economy 2008年第2期16卷 1-18页

作者： John Wong East Asian Institute National University of SingaporeSingaporeSingapore

Fuelled by high domestic investment and rapid export expansion, China ＂s economy grew by ll.4 pereent in 2007, the highest increase since 1994 and the fifth eonseeutive year of double-digit growth. Such spectacular growth performance is unprecedented in the world＇s economic history. However, the Chinese Government is again worried about a possible ＂hard landing＂for the economy, as no economy can sustain very strong growth for extremely long period without overheating. Cracks in China ＂s economy are indeed emerging. The eonsumer priee index shot up to 6.9percent in November 2007, the highest level in a decade, with the annual inflation for 2007 rising to 4.S pereent, well above the government＇s ＂comfort level＂ of 3 percent. This prompted China＇s top leadership to declare that reducing economic overheating and curbing inflation would be the top poliey priorities for 2008. To contain such cost-push inflation, the government has to tackle its root causes, such as excessive liquidity, which is caused by the undervaluation of the renminbi, which in turn is attributable to China＇s chronic external and internal maeroeeonomie imbalances~ High growth is likely to continue in 2008, at around l O pereent, with inflation of S-6 pereent expected, despite the anticipated tighter maeroeeonomie control measures and the more troubled external economic environment （e.g. the expected US economic slowdown）. Regardless, China ＂s fundamental problems associated with runaway growth will largely remain. In addition, if the US economy slips into a serious recession, the Chinese economy will not be able to deeouple from it and escape unscathed.

关键词： high growth domestic demand overheating inflation recession

Rational points and zeta functions of some curves over finite fields

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Science China Mathematics 2010年第11期53卷 2855-2863页

作者： WANG Long1, & LUO JinQuan2,3 1Department of Mathematical Sciences, Tsinghua University, Beijing 100084, China 2School of Mathematical Sciences, Yangzhou University, Yangzhou 225002, China 3Division of Mathematical Sciences, School of Physical and Mathematical Sciences, Nanyang Technology University, 637371, singapore 1. Department of Mathematical Sciences Tsinghua University Beijing 100084 China2. School of Mathematical Sciences Yangzhou University Yangzhou 225002 China3. Division of Mathematical Sciences School of Physical and Mathematical Sciences Nanyang Technology University Singapore 637371 Singapore

In this paper we study the number of rational points on some curves over finite fields. Moreover, zeta functions of the associated function fields are evaluated explicitly.

关键词： exponential sum rational point rational place zeta function

Retrieval of suspended sediment concentrations in the turbid water of the Upper Yangtze River using Landsat ETM+

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Science Bulletin 2007年第S2期 273-280页

作者： WANG JianJun~(1+) LU XiXi~1 ZHOU Yue~2 1 Department of Geography,National University of singapore,10 Kent Ridge Crescent,119260 singapore 2 Department of Environmental Science,Kunming University of Science and Technology,Kunming 650093,China

For the remote areas like the Longitudinal Range-Gorge Region(LRGR),it is hard to measure the sus- pended sediment concentrations(SSC).This study attempted to estimate SSC by employing the three atmospheric correction methods:COST,iCOST(modified from COST)and TZB5(newly proposed). TZB5 can more accurately determine the atmospheric transmittance along the sun-ground surface path (TAUz)from the solar zenith angle(TZ),and it uses Band 5 to eliminate the path radiance of Bands 1—*** water surface reflectance at Band 4 obtained using TZB5 has a stronger relation with SSC within the range of 0-3000 mg/*** developed algorithms could accurately estimate SSC directly from ETM+ Images in the turbid Upper Yangtze River,and were also effective in the Middle Yangtze River.

关键词： image-based atmospheric correction suspended sediment concentration(SSC) Landsat ETM+image turbid water the Upper Yangtze River