Distribution,interoperability,interactivity,component are four main features of distributed GIS.Based on the principle of hypermap,hypermedia and distributed database,the paper comes up with a kind of distributed spat...Distribution,interoperability,interactivity,component are four main features of distributed GIS.Based on the principle of hypermap,hypermedia and distributed database,the paper comes up with a kind of distributed spatial data model which is in accordance with those features of distributed GIS.The model takes catalog service as the outline of spatial information globalization,and defines data structure of hypermap node in different level.Based on the model,it is feasible to manage and process distributed spatial information,and integrate multi_source,heterogeneous spatial data into a framework.Traditionally,to retrieve and access spatial data via Internet is only by theme or map name.With the concept of the model,it is possible to retrieve,load,and link spatial data by vector_based graphics on the Internet.展开更多
The aim of the international project “Global Land Ice Measurements from Space (GLIMS)" headed by the US Geological Survey is to establish a world wide glacier inventory based on satellite imagery.This data set w...The aim of the international project “Global Land Ice Measurements from Space (GLIMS)" headed by the US Geological Survey is to establish a world wide glacier inventory based on satellite imagery.This data set will form a first digital baseline study for future glacier monitoring.The presented GIS_based glacier inventory for King George Island is a case study for the area of the Antarctic Peninsula.In the database of the glacier inventory topographic information,specific glaciological parameters as well as metadata will be included.The topographic data consists of drainage basin limits,basin areas,altitudinal ranges,perimeters and mean lengths.Glaciological data sets should comprise information on glacier retreat in different periods,glacier velocities,ice thickness and bedrock topography as well as derived parameters.Modelled and measured mass balance parameters could be included as additional data layers.In particular,these metadata records must comprise background information on data accuracy and data sources and should be compatible with a future data model for the King George Island GIS (KGIS).Three examples illustrate that the GLIMS database will not only contain information valuable for glaciological applications,but also other environmental studies on the island will benefit from this standardised remote sensing data sets.Therefore,a very close link between the data models of KGIS and GLIMS has to be established to enable these synergisms.Finally,better access to historic aerial photography would enable a continuous record of glacier retreat from the beginning of the 1950’s onward.展开更多
An improved topographic database for King George Island,one of the most frequently visited regions in Antarctica,is presented.A first step consisted in combining data from differential GPS surveys gained during the au...An improved topographic database for King George Island,one of the most frequently visited regions in Antarctica,is presented.A first step consisted in combining data from differential GPS surveys gained during the austral summers 1997～1998 and 1999～2000,with the current coastline from a SPOT satellite image mosaic,topographic information from existing maps and from the Antarctic Digital Database.From this data sets,a digital terrain model (DTM) was generated using Arc/Info GIS.In a second step,a satellite image map at the scale 1∶100 000 was assembled from contour lines derived from the DTM and the satellite mosaic.A lack of accurate topographic information in the eastern part of the island was identified.Additional topographic surveying or SAR interferometry should be used to improve the data quality in that area.The GIS integrated database will be indispensable for glaciological and climatological studies and administrative and scientific purposes.In future,the application of GIS techniques will be mandatory for environmental impact studies and environmental monitoring as well as for management plans on King George Island.展开更多
After Donald Trump was elected US president,his controversial foreign policy disrupted the world situation,bringing about a series of disagreements and disputes with Germany and with Europe as a whole.As the two major...After Donald Trump was elected US president,his controversial foreign policy disrupted the world situation,bringing about a series of disagreements and disputes with Germany and with Europe as a whole.As the two major powers in the West,Germany and the United States,in a state of dispute,will have multiple effects.These disputes undoubtedly show that the German-US relations are undergoing a major adjustment and reorientation.We must also realize that disputes between Germany and the United States have alienated relations between the two countries.However,the foundation on the overall Western values between the two countries has not changed.They still have a great deal of common ground on politics,economy and security.Therefore,these disagreements and disputes will not lead to the collapse of German-US relations.Cooperation vs.controversy,control vs.independence,further equalization and alienation of the two countries will characterize future developments in German-US relations.展开更多
HUNAN’S“king of mask changing” is the 70-year-old Zeng Jingui. He spent most of his working life in Chinese opera,and has brought this passion into his retirement. The 70-year-old operates an opera mask workshop fr...HUNAN’S“king of mask changing” is the 70-year-old Zeng Jingui. He spent most of his working life in Chinese opera,and has brought this passion into his retirement. The 70-year-old operates an opera mask workshop from his two-room apartment. It is crammed with thousands of different-sized facemasks seen in traditional Chinese operas.展开更多
The Trump administration's hostile trade actions against China since the beginning of this year violate World Trade Organization rules. To protect the free trade world economic system, China has stood up to fight ...The Trump administration's hostile trade actions against China since the beginning of this year violate World Trade Organization rules. To protect the free trade world economic system, China has stood up to fight this trade bullying. When the US administration continued with harsher actions, the escalation in trade friction increased the potential harm for both countries. China has been very clear that Trump's trade tariffs cannot improve the bilateral trade imbalance. Tit-for-tat ought to be a last resort but China is open to talking. Now the ball is in Trump's court. As two big,influential economies, China and the US should calm down and go back to negotiating table to avoid a trade war trap. Bullying is only one approach President Trump can choose, but arbitrary threats are no solution.展开更多
基金ProjectsupportedbyCNSFforLIESMARSGrant (No .9871 0 66)
文摘Distribution,interoperability,interactivity,component are four main features of distributed GIS.Based on the principle of hypermap,hypermedia and distributed database,the paper comes up with a kind of distributed spatial data model which is in accordance with those features of distributed GIS.The model takes catalog service as the outline of spatial information globalization,and defines data structure of hypermap node in different level.Based on the model,it is feasible to manage and process distributed spatial information,and integrate multi_source,heterogeneous spatial data into a framework.Traditionally,to retrieve and access spatial data via Internet is only by theme or map name.With the concept of the model,it is possible to retrieve,load,and link spatial data by vector_based graphics on the Internet.
文摘The aim of the international project “Global Land Ice Measurements from Space (GLIMS)" headed by the US Geological Survey is to establish a world wide glacier inventory based on satellite imagery.This data set will form a first digital baseline study for future glacier monitoring.The presented GIS_based glacier inventory for King George Island is a case study for the area of the Antarctic Peninsula.In the database of the glacier inventory topographic information,specific glaciological parameters as well as metadata will be included.The topographic data consists of drainage basin limits,basin areas,altitudinal ranges,perimeters and mean lengths.Glaciological data sets should comprise information on glacier retreat in different periods,glacier velocities,ice thickness and bedrock topography as well as derived parameters.Modelled and measured mass balance parameters could be included as additional data layers.In particular,these metadata records must comprise background information on data accuracy and data sources and should be compatible with a future data model for the King George Island GIS (KGIS).Three examples illustrate that the GLIMS database will not only contain information valuable for glaciological applications,but also other environmental studies on the island will benefit from this standardised remote sensing data sets.Therefore,a very close link between the data models of KGIS and GLIMS has to be established to enable these synergisms.Finally,better access to historic aerial photography would enable a continuous record of glacier retreat from the beginning of the 1950’s onward.
文摘An improved topographic database for King George Island,one of the most frequently visited regions in Antarctica,is presented.A first step consisted in combining data from differential GPS surveys gained during the austral summers 1997～1998 and 1999～2000,with the current coastline from a SPOT satellite image mosaic,topographic information from existing maps and from the Antarctic Digital Database.From this data sets,a digital terrain model (DTM) was generated using Arc/Info GIS.In a second step,a satellite image map at the scale 1∶100 000 was assembled from contour lines derived from the DTM and the satellite mosaic.A lack of accurate topographic information in the eastern part of the island was identified.Additional topographic surveying or SAR interferometry should be used to improve the data quality in that area.The GIS integrated database will be indispensable for glaciological and climatological studies and administrative and scientific purposes.In future,the application of GIS techniques will be mandatory for environmental impact studies and environmental monitoring as well as for management plans on King George Island.
文摘After Donald Trump was elected US president,his controversial foreign policy disrupted the world situation,bringing about a series of disagreements and disputes with Germany and with Europe as a whole.As the two major powers in the West,Germany and the United States,in a state of dispute,will have multiple effects.These disputes undoubtedly show that the German-US relations are undergoing a major adjustment and reorientation.We must also realize that disputes between Germany and the United States have alienated relations between the two countries.However,the foundation on the overall Western values between the two countries has not changed.They still have a great deal of common ground on politics,economy and security.Therefore,these disagreements and disputes will not lead to the collapse of German-US relations.Cooperation vs.controversy,control vs.independence,further equalization and alienation of the two countries will characterize future developments in German-US relations.
文摘HUNAN’S“king of mask changing” is the 70-year-old Zeng Jingui. He spent most of his working life in Chinese opera,and has brought this passion into his retirement. The 70-year-old operates an opera mask workshop from his two-room apartment. It is crammed with thousands of different-sized facemasks seen in traditional Chinese operas.
文摘The Trump administration's hostile trade actions against China since the beginning of this year violate World Trade Organization rules. To protect the free trade world economic system, China has stood up to fight this trade bullying. When the US administration continued with harsher actions, the escalation in trade friction increased the potential harm for both countries. China has been very clear that Trump's trade tariffs cannot improve the bilateral trade imbalance. Tit-for-tat ought to be a last resort but China is open to talking. Now the ball is in Trump's court. As two big,influential economies, China and the US should calm down and go back to negotiating table to avoid a trade war trap. Bullying is only one approach President Trump can choose, but arbitrary threats are no solution.
