With abundant wind resources and high pressure imposed on en-vironmental protection, wind power development has a promising future. Butdue to intermittent nature, wind power can bring into full play only if being con-...With abundant wind resources and high pressure imposed on en-vironmental protection, wind power development has a promising future. Butdue to intermittent nature, wind power can bring into full play only if being con-nected into power grid to ensure its supply reliability and continuity, aswell as operational economy. However, technical and market barriers haveprevented wind power from integrating into power grid. To foster wind powerdevelopment, these barriers should be removed by both government incentivepolicies and sophisticated technologies.展开更多
为归纳长江口深水航道台风期骤淤的发生规律及特征,分析了发生骤淤时刻的气象条件与对应的波浪条件。研究发现,牛皮礁站的波能与骤淤具有较好的相关性;从台风路径上分析,长江口东侧过境台风对航道的骤淤影响显著。结合历史台风路径,选取...为归纳长江口深水航道台风期骤淤的发生规律及特征,分析了发生骤淤时刻的气象条件与对应的波浪条件。研究发现,牛皮礁站的波能与骤淤具有较好的相关性;从台风路径上分析,长江口东侧过境台风对航道的骤淤影响显著。结合历史台风路径,选取3个典型路径的台风,选择藤田-高桥圆形经验风场和CFSR(climate forecast system reanalysis)风场的混合风场复演了台风场,然后采用SWAN模型模拟了不同路径台风期间的波况,最后以牛皮礁站的浅水波能流为判别参数,分析不同路径台风对长江口深水航道骤淤的影响。研究表明长江口东侧过境的台风是较易产生较大波能并进一步诱发骤淤的典型台风路径,这一分析结果与2010年以来的骤淤实测台风路径结果吻合。展开更多
History has brought us into a significant moment when the majority of the human kind has taken up resi-dence in urban settlements. The focus of global urbanization has shifted to the developing world and the center of...History has brought us into a significant moment when the majority of the human kind has taken up resi-dence in urban settlements. The focus of global urbanization has shifted to the developing world and the center of manufacturing is no longer confined to the Global North. This paper provides a periodical assessment of the current status of China's urban transformation in the global context of a shifting emphasis of industrialization and urbaniza-tion. China's phenomenal urban transformation deserves a special attention not only because of its unparalleled scale and speed but also because of its distinct trajectory of growth that does not conform to normal theoretical ex-pectations. The results of assessment revealed an urban economy with remarkable hybridity, a society that is in-creasingly stratified, polarized, and segregated, and a juxtaposed urban space undergoing restless and pervasive transformation. A decentering world should entail a decentering knowledge production. A critical reflection upon the Chinese patterns and processes of urban transformation has identified 4 main issues with great potentials for inno-vative knowledge production, namely: 1) privatization and economic development; 2) state, society, and space; 3) urbanization of capital, labor, and land; and 4) the environment and Chinese political ecology. The paper closes with the remark that a rapidly transforming urban China has presented itself as a fertile and resourceful testing ground for critical and innovative geographic enquiries.展开更多
The SMOS(soil moisture and ocean salinity) mission undertaken by the European Space Agency(ESA) has provided sea surface salinity(SSS) measurements at global scale since 2009.Validation of SSS values retrieved from SM...The SMOS(soil moisture and ocean salinity) mission undertaken by the European Space Agency(ESA) has provided sea surface salinity(SSS) measurements at global scale since 2009.Validation of SSS values retrieved from SMOS data has been done globally and regionally.However,the accuracy of SSS measurements by SMOS in the China seas has not been examined in detail.In this study,we compared retrieved SSS values from SMOS data with in situ measurements from a South China Sea(SCS) expedition during autumn 2011.The comparison shows that the retrieved SSS values using ascending pass data have much better agreement with in situ measurements than the result derived from descending pass data.Accuracy in terms of bias and root mean square error(RMS) of the SSS retrieved using three different sea surface roughness models is very consistent,regardless of ascending or descending orbits.When ascending and descending measurements are combined for comparison,the retrieved SSS using a semi-empirical model shows the best agreement with in situ measurements,with bias-0.33 practical salinity units and RMS 0.74.We also investigated the impact of environmental conditions of sea surface wind and sea surface temperature on accuracy of the retrieved SSS.The SCS is a semi-closed basin where radio frequencies transmitted from the mainland strongly interfere with SMOS measurements.Therefore,accuracy of retrieved SSS shows a relationship with distance between the validation sites and land.展开更多
文摘With abundant wind resources and high pressure imposed on en-vironmental protection, wind power development has a promising future. Butdue to intermittent nature, wind power can bring into full play only if being con-nected into power grid to ensure its supply reliability and continuity, aswell as operational economy. However, technical and market barriers haveprevented wind power from integrating into power grid. To foster wind powerdevelopment, these barriers should be removed by both government incentivepolicies and sophisticated technologies.
文摘为归纳长江口深水航道台风期骤淤的发生规律及特征,分析了发生骤淤时刻的气象条件与对应的波浪条件。研究发现,牛皮礁站的波能与骤淤具有较好的相关性;从台风路径上分析,长江口东侧过境台风对航道的骤淤影响显著。结合历史台风路径,选取3个典型路径的台风,选择藤田-高桥圆形经验风场和CFSR(climate forecast system reanalysis)风场的混合风场复演了台风场,然后采用SWAN模型模拟了不同路径台风期间的波况,最后以牛皮礁站的浅水波能流为判别参数,分析不同路径台风对长江口深水航道骤淤的影响。研究表明长江口东侧过境的台风是较易产生较大波能并进一步诱发骤淤的典型台风路径,这一分析结果与2010年以来的骤淤实测台风路径结果吻合。
基金Under the auspices of the Research Grants Council of the Hong Kong Special Administrative Region, China (No. GRF HKU-747509H)Mrs. Li Ka Shing Fund for Contemporary China Studies Strategic Research Theme (No. HKU-20388025)the Small Project Funding of the University of Hong Kong (No. HKU-10400706)
文摘History has brought us into a significant moment when the majority of the human kind has taken up resi-dence in urban settlements. The focus of global urbanization has shifted to the developing world and the center of manufacturing is no longer confined to the Global North. This paper provides a periodical assessment of the current status of China's urban transformation in the global context of a shifting emphasis of industrialization and urbaniza-tion. China's phenomenal urban transformation deserves a special attention not only because of its unparalleled scale and speed but also because of its distinct trajectory of growth that does not conform to normal theoretical ex-pectations. The results of assessment revealed an urban economy with remarkable hybridity, a society that is in-creasingly stratified, polarized, and segregated, and a juxtaposed urban space undergoing restless and pervasive transformation. A decentering world should entail a decentering knowledge production. A critical reflection upon the Chinese patterns and processes of urban transformation has identified 4 main issues with great potentials for inno-vative knowledge production, namely: 1) privatization and economic development; 2) state, society, and space; 3) urbanization of capital, labor, and land; and 4) the environment and Chinese political ecology. The paper closes with the remark that a rapidly transforming urban China has presented itself as a fertile and resourceful testing ground for critical and innovative geographic enquiries.
基金Supported by the National Natural Science Foundation of China(Nos.41006110,41106155)
文摘The SMOS(soil moisture and ocean salinity) mission undertaken by the European Space Agency(ESA) has provided sea surface salinity(SSS) measurements at global scale since 2009.Validation of SSS values retrieved from SMOS data has been done globally and regionally.However,the accuracy of SSS measurements by SMOS in the China seas has not been examined in detail.In this study,we compared retrieved SSS values from SMOS data with in situ measurements from a South China Sea(SCS) expedition during autumn 2011.The comparison shows that the retrieved SSS values using ascending pass data have much better agreement with in situ measurements than the result derived from descending pass data.Accuracy in terms of bias and root mean square error(RMS) of the SSS retrieved using three different sea surface roughness models is very consistent,regardless of ascending or descending orbits.When ascending and descending measurements are combined for comparison,the retrieved SSS using a semi-empirical model shows the best agreement with in situ measurements,with bias-0.33 practical salinity units and RMS 0.74.We also investigated the impact of environmental conditions of sea surface wind and sea surface temperature on accuracy of the retrieved SSS.The SCS is a semi-closed basin where radio frequencies transmitted from the mainland strongly interfere with SMOS measurements.Therefore,accuracy of retrieved SSS shows a relationship with distance between the validation sites and land.
