A statistical comparison of the CO₂ measurements at Cape St. James and Station "P", Canada     

K. HIGUCHI  V. HUDEC  N. B. A. TRIVETT  C. W. YUEN  D. CHAN  C. S. WONG 《Tellus. Series B, Chemical and physical meteorology》1995,47(1-2):4-16

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Growth and photosynthesis of Chlorella strains from polar,temperate and tropical freshwater environments under temperature stress     

Kok-Keong LEE  Phaik-Eem LIM  Sze-Wan POONG  Chiew-Yen WONG  Siew-Moi PHANG  John BEARDALL 《中国海洋湖沼学报》2018,(4)

Elevated temperatures as a consequence of global warming have significant impacts on the adaptation and survival of microalgae which are important primary producers in many ecosystems. The impact of temperature on the photosynthesis of microalgae is of great interest as the primary production of algal biomass is strongly dependent on the photosynthetic rates in a dynamic environment. Here, we examine the effects of elevated temperature on Chlorella strains originating from different latitudes, namely Antarctic, Arctic, temperate and tropical regions. Chlorophyll fluorescence was used to assess the photosynthetic responses of the microalgae. Rapid light curves(RLCs) and maximum quantum yield( F_v/F_m) were recorded. The results showed that Chlorella originating from different latitudes portrayed different growth trends and photosynthetic performance. The Chlorella genus is eurythermal, with a broad temperature tolerance range, but with strain-specific characteristics. However, there was a large overlap between the tolerance range of the four strains due to their "eurythermal adaptivity". Changes in the photosynthetic parameters indicated temperature stress. The ability of the four strains to reactivate photosynthesis after inhibition of photosynthesis under high temperatures was also studied. The Chlorella strains were shown to recover in terms of photosynthesis and growth(measured as Chl a) when they were returned to their ambient temperatures. Polar strains showed faster recovery in their optimal temperature compared to that under the ambient temperature from which they were isolated.  相似文献   

Use of artificial flood events to demonstrate the invalidity of simple mixing models     

TOMMY S. W. WONG 《水文科学杂志》2013,58(5):833-837

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Influence of upstream inflow on wave celerity and time to equilibrium on an overland plane     

TOMMY S. W. WONG 《水文科学杂志》2013,58(2):195-205

Abstract

Based on the kinematic wave equations, formulae for the wave celerity along an overland plane subject to uniform rainfall excess and with a constant upstream inflow together with the corresponding average wave celerity and time to equilibrium for the entire plane are derived. The formulae are further developed in terms of both the Darcy-Weisbach resistance coefficient and the Manning resistance coefficient. By comparing the wave celerities, the average wave celerities and the time to equilibrium for planes with and without upstream inflow show that the upstream inflow causes the wave celerity and the average wave celerity to be faster and the times to equilibrium to be shorter. The effect of upstream inflow is greater with increasing inflow, but the marginal effect decreases with increasing inflow. The effect is greatest for laminar flow and least for turbulent flow. For the wave celerity, the effect is also greatest at the upstream end of the plane and least at the downstream end of the plane.  相似文献   

遥感技术在土地调查与动态监测中的应用综述   总被引：1，自引：0，他引：1  

翁玉坤  刘排英  王鹏生 《北京测绘》2009,(3):60-62

从土地利用现状调查和动态监测的技术流程入手，以融合成图和土地动态监测为重点，对流程中各个步骤作了明确简要的介绍，并系统地介绍了现代遥感技术在土地调查应用方面的优势和不足。  相似文献   

Climatic effect on DMS producers in the NE sub-Arctic Pacific: ENSO on the upper ocean     

CHI-SHING WONG  SHAU-KING EMMY WONG  ANGELICA PEÑA  MAURICE LEVASSEUR 《Tellus. Series B, Chemical and physical meteorology》2006,58(4):319-326

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Application of Multi-Scale Tracking Radar Echoes Scheme in Quantitative Precipitation Nowcasting     

WANG Gaili  WONG Waikin  LIU Liping  WANG Hongyan 《大气科学进展》2013,30(2):448-460

A new radar echo tracking algorithm known as multi-scale tracking radar echoes by cross-correlation(MTREC) was developed in this study to analyze movements of radar echoes at different spatial scales.Movement of radar echoes,particularly associated with convective storms,exhibits different characteristics at various spatial scales as a result of complex interactions among meteorological systems leading to the formation of convective storms.For the null echo region,the usual correlation technique produces zero or a very small magnitude of motion vectors.To mitigate these constraints,MTREC uses the tracking radar echoes by correlation(TREC) technique with a large "box" to determine the systematic movement driven by steering wind,and MTREC applies the TREC technique with a small "box" to estimate small-scale internal motion vectors.Eventually,the MTREC vectors are obtained by synthesizing the systematic motion and the small-scale internal motion.Performance of the MTREC technique was compared with TREC technique using case studies:the Khanun typhoon on 11 September 2005 observed by Wenzhou radar and a squall-line system on 23 June 2011 detected by Beijing radar.The results demonstrate that more spatially smoothed and continuous vector fields can be generated by the MTREC technique,which leads to improvements in tracking the entire radar reflectivity pattern.The new multi-scale tracking scheme was applied to study its impact on the performance of quantitative precipitation nowcasting.The location and intensity of heavy precipitation at a 1-h lead time was more consistent with quantitative precipitation estimates using radar and rain gauges.  相似文献   

Temporal and spatial distribution of dimethylsulfide in the subarctic northeast Pacific Ocean: a high-nutrient–low-chlorophyll region     

C. S. WONG  S. E. WONG  W. A. RICHARDSON  G. E. SMITH  M. D. ARYCHUK  J. S. PAGE 《Tellus. Series B, Chemical and physical meteorology》2005,57(4):317-331

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Temporal variations in the partial pressure and flux of CO₂ at ocean station P in the subarctic northeast Pacific Ocean     

C. S. WONG  Y.-H. CHAN 《Tellus. Series B, Chemical and physical meteorology》1991,43(2):206-223

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Towards a framework for learning with GIS: The case of Urban World, a hypermap learning environment based on GIS     

DEREK THOMPSON  FRANCIS E LINDSAY  PAUL E DAVIS  DAVID W S WONG 《Transactions in GIS》1997,2(2):151-167

Off-the-shelf GIS toolboxes are inadequate for pedagogic purposes. Urban World , an Arc View application, attempts to address this shortcoming by including special features designed to foster student progress towards a better understanding of urban environments. This paper provides context for the Urban World system in an active, authentic learning environment for students of urban geography and planning at junior and senior levels in undergraduate curricula at universities in the United States. The paper describes the rationale for, and implementation of, several components of Urban World : a special graphid user interface; productivity tools for facilitating the acquisition of practical skills of mapping and spatial analysis; tools for accessing, undertaking, and submitting homework assignments in a paper-less class; and various devices for assisting students to undertake spatial reasoning. GIS are Seen as an enabling technology for improving understanding by means of engaging students in empirical analysis. Spatial problem solvers and decision makers reach sound conclusions by employing reasoning skills applied to well-formed databases; scientific research makcs progress with sound reasoning of many types. The effective teaching and learning about the geography of our world requires a strong foundation of spatid reasoning.  相似文献