This paper is a comprehensive discussion about a few theoretical issues of historical strata analysis, that is, uniformitarianism and neogramarian hypothesis,catastrophism and borrowing, wendu and ba-id^u readings, na...This paper is a comprehensive discussion about a few theoretical issues of historical strata analysis, that is, uniformitarianism and neogramarian hypothesis,catastrophism and borrowing, wendu and ba-id^u readings, native stratum, identification of loan strata and native stratum, influence and borrowing, and real time and apparent time.展开更多
The spatial resolution of source data, the impact factor selection on the grid model and the size of the grid might be the main limitations of global land datasets applied on a regional scale. Quantitative studies of ...The spatial resolution of source data, the impact factor selection on the grid model and the size of the grid might be the main limitations of global land datasets applied on a regional scale. Quantitative studies of the impacts of rasterization on data accuracy can help improve data resolution and regional data accuracy. Through a case study of cropland data for Jiangsu and Anhui provinces in China, this research compared data accuracy with different data sources, rasterization methods, and grid sizes. First, we investigated the influence of different data sources on gridded data accuracy. The temporal trends of the History Database of the Global Environment （HYDE）, Chinese Historical Cropland Data （CHCD）, and Suwan Cropland Data （SWCD） datasets were more similar. However, differ- ent spatial resolutions of cropland source data in the CHCD and SWCD datasets revealed an average difference of 16.61% when provin- cial and county data were downscaled to a 10 x 10 km2 grid for comparison. Second, the influence of selection of the potential arable land reclamation rate and temperature factors, as well as the different processing methods for water factors, on accuracy of gridded datasets was investigated. Applying the reclamation rate of potential cropland to grid-processing increased the diversity of spatial distri- bution but resulted in only a slightly greater standard deviation, which increased by 4.05. Temperature factors only produced relative disparities within 10% and absolute disparities within 2 km2 over more than 90% of grid cells. For the different processing methods for water factors, the HYDE dataset distributed 70% more cropland in grid cells along riverbanks, at the abandoned Yellow River Estuary （located in Binhai County, Yancheng City, Jiangsu Province）, and around Hongze Lake, than did the SWCD dataset. Finally, we ex- plored the influence of different grid sizes. Absolute accuracy disparities by unit area for the year 2000 were within 0.1 km2 at a 1 km2 grid size, a 25% improvement over the 10 km2 grid size. Compared to the outcomes of other similar studies, this demonstrates that some model hypotheses and grid-processing methods in international land datasets are truly incongruent with actual land reclamation proc- esses, at least in China. Combining the model-based methods with historical empirical data may be a better way to improve the accuracy of regional scale datasets. Exploring methods for the above aspects improved the accuracy of historical crop/and gridded datasets for finer regional scales.展开更多
In recent years,relations between Japan and the Republic of Korea(hereafter referred to as South Korea)have become tense,giving rise to economic and trade frictions between them,and plunging their bilateral relationsh...In recent years,relations between Japan and the Republic of Korea(hereafter referred to as South Korea)have become tense,giving rise to economic and trade frictions between them,and plunging their bilateral relationship to an all-time low.The disputes between Japan and South Korea have exhibited the features of endurance,expansion in disputing areas,and a frequent switch from defense to offense or vice versa on both sides.The fast deteriorating relationship between Japan and South Korea has resulted from multiple factors that interact in an entangled way,including mutually enhancing old and new grievances and discontent over historical issues,the adjustment of foreign policies by Japan and South Korea,the rise of nationalist emotions in both countries,US adjustment of its alliance policy towards the Asia-Pacific,and structural competition in forming the regional order.As the structural contradictions between Japan and South Korea appear hard to overcome,the potential for the tense relationship between the two countries to persist is mounting,and this will lead to new repercussions on the regional order.展开更多
文摘This paper is a comprehensive discussion about a few theoretical issues of historical strata analysis, that is, uniformitarianism and neogramarian hypothesis,catastrophism and borrowing, wendu and ba-id^u readings, native stratum, identification of loan strata and native stratum, influence and borrowing, and real time and apparent time.
基金Under the auspices of National Natural Science Foundation of China(No.41471156,41501207)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA05080102)Special Fund of National Science and Technology of China(No.2014FY130500)
文摘The spatial resolution of source data, the impact factor selection on the grid model and the size of the grid might be the main limitations of global land datasets applied on a regional scale. Quantitative studies of the impacts of rasterization on data accuracy can help improve data resolution and regional data accuracy. Through a case study of cropland data for Jiangsu and Anhui provinces in China, this research compared data accuracy with different data sources, rasterization methods, and grid sizes. First, we investigated the influence of different data sources on gridded data accuracy. The temporal trends of the History Database of the Global Environment （HYDE）, Chinese Historical Cropland Data （CHCD）, and Suwan Cropland Data （SWCD） datasets were more similar. However, differ- ent spatial resolutions of cropland source data in the CHCD and SWCD datasets revealed an average difference of 16.61% when provin- cial and county data were downscaled to a 10 x 10 km2 grid for comparison. Second, the influence of selection of the potential arable land reclamation rate and temperature factors, as well as the different processing methods for water factors, on accuracy of gridded datasets was investigated. Applying the reclamation rate of potential cropland to grid-processing increased the diversity of spatial distri- bution but resulted in only a slightly greater standard deviation, which increased by 4.05. Temperature factors only produced relative disparities within 10% and absolute disparities within 2 km2 over more than 90% of grid cells. For the different processing methods for water factors, the HYDE dataset distributed 70% more cropland in grid cells along riverbanks, at the abandoned Yellow River Estuary （located in Binhai County, Yancheng City, Jiangsu Province）, and around Hongze Lake, than did the SWCD dataset. Finally, we ex- plored the influence of different grid sizes. Absolute accuracy disparities by unit area for the year 2000 were within 0.1 km2 at a 1 km2 grid size, a 25% improvement over the 10 km2 grid size. Compared to the outcomes of other similar studies, this demonstrates that some model hypotheses and grid-processing methods in international land datasets are truly incongruent with actual land reclamation proc- esses, at least in China. Combining the model-based methods with historical empirical data may be a better way to improve the accuracy of regional scale datasets. Exploring methods for the above aspects improved the accuracy of historical crop/and gridded datasets for finer regional scales.
文摘In recent years,relations between Japan and the Republic of Korea(hereafter referred to as South Korea)have become tense,giving rise to economic and trade frictions between them,and plunging their bilateral relationship to an all-time low.The disputes between Japan and South Korea have exhibited the features of endurance,expansion in disputing areas,and a frequent switch from defense to offense or vice versa on both sides.The fast deteriorating relationship between Japan and South Korea has resulted from multiple factors that interact in an entangled way,including mutually enhancing old and new grievances and discontent over historical issues,the adjustment of foreign policies by Japan and South Korea,the rise of nationalist emotions in both countries,US adjustment of its alliance policy towards the Asia-Pacific,and structural competition in forming the regional order.As the structural contradictions between Japan and South Korea appear hard to overcome,the potential for the tense relationship between the two countries to persist is mounting,and this will lead to new repercussions on the regional order.
