The North Korea nuclear challenge,urgent on the US foreign policy agenda since Donald Trump took office,has prompted unilateral,bilateral and multilateral moves to address rising tension on the peninsula.The underlyin...The North Korea nuclear challenge,urgent on the US foreign policy agenda since Donald Trump took office,has prompted unilateral,bilateral and multilateral moves to address rising tension on the peninsula.The underlying logic of US policy,which in November placed the DPRK back on the list of state sponsors of terrorism,promotes negotiation by imposing Maximum Pressure and by enlisting China's support.Possibly,North Korea will return to negotiations with its nuclear and missile development suspended temporarily.Other possibilities are a stalemate with North Korea joining the ranks of countries with credible nuclear deterrent,or an emerging crisis that escalates to military or other conflict.The lingering uncertainty is central to northeast Asia security.展开更多
Studies on long-term change of cropland is of great significance to the utilization of land resources and the implementation of scientific agricultural policies. The Korean Peninsula, adjacent to China, plays an impor...Studies on long-term change of cropland is of great significance to the utilization of land resources and the implementation of scientific agricultural policies. The Korean Peninsula, adjacent to China, plays an important role in the international environment of Northeast Asia. The Korean Peninsula includes South Korea and North Korea—two countries that have a great difference in their institutions and economic developments. Therefore, we aim to quantify the spatiotemporal changes of croplands in these two countries using Landsat Thematic Imager(TM) and Operational Land Imager(OLI) imagery, and to compare the differences of cropland changes between the two countries. This paper take full advantage of ODM approach(object-oriented segmentation and decision-tree classification based on multi-season imageries) to obtain the distribution of croplands in 1990 and 2015. Results showed that the overall classification accuracy of cropland data is 91.10% in 1990 and 92.52% in 2015. The croplands were mainly distributed in areas with slopes that were less than 8° and with elevations that were less than 300 m in the Korean Peninsula. However, in other region(slope > 8° or elevation > 300 m), the area and proportion of North Korea's croplands were significantly higher than that of South Korea. Croplands significantly increased by 15.02% in North Korea from 1990 to 2015. In contrast, croplands in South Korea slightly decreased by 1.32%. During the 25 years, policy shift, economic development, population growth, and urban sprawl played primary roles for cropland changes. Additionally, the regional differences of cropland changes were mainly due to different agriculture policies implemented by different countries. The achievements of this study can provide scientific guidance for the protection and sustainability of land resources.展开更多
Bases on studies of bryophytes collecled by Cao Tong in August 1997 from North Kolea, 81 species belonging to 52 genera, 26 families of mosses and 16 species belonging to 12 genera, 10 families of hepatics are recorde...Bases on studies of bryophytes collecled by Cao Tong in August 1997 from North Kolea, 81 species belonging to 52 genera, 26 families of mosses and 16 species belonging to 12 genera, 10 families of hepatics are recorded. Among these, 6 rpeciec and 1 form are new to bryoflora of the Korean Peninsula. These are : Campylopus gracilis (Mitt.) Jaeg.,Grimmia leavigata (Brid.) Brid., Okamura hakoniensis f. mutiflagellifera (Okam.) Nog., Orthotrchum erubescens C. Muell.,Scapania verrucosa Heeg., Schistidum strictum (Turn.) Loeske ex O. Maort. and Schistidium subconfertum (Broth.)Deguchi.展开更多
Due to considerable deforestation in North Korea,there is a need to plan forest restoration programs based on scientific forest management.In this study,a methodology was developed for estimating the site index values...Due to considerable deforestation in North Korea,there is a need to plan forest restoration programs based on scientific forest management.In this study,a methodology was developed for estimating the site index values of six major tree species and the forest productivity potential.The site index values of these tree species were derived in South Korea using the Chapman-Richards equation.These values were used with data from the 6th National Forest Inventory,which included 20 types of edaphic,topographic,and climatic factors,and random forest analysis—a widely used machine learning technique for spatial prediction—to develop a new model for estimating the site index values of these species across South Korea.The prediction accuracy of this model was evaluated using the root mean square error.The results show that the prediction accuracy was high,with a root mean square error of~1m.Moreover,the importance of the variables related to climate and geography was generally high.The proposed site index estimation model for six tree species was applied across North Korea,and its effectiveness tested by comparing the estimated values with those reported in literature from North Korea.The differences between the model outputs and recorded data in the northern alpine regions were presumably due to the lack of data for high-altitude regions in South Korea.This model is based on the determination of the suitability of tree species in restoration efforts.Therefore,it can contribute to the evaluation of forest productivity in North Korea and may help plan efficient forest restoration programs.展开更多
The objective of this study was to investigate the epidemiology of bovine Piroplasms infections in the Rasǒn area of North Korea.The survey was carried out by light microscopic examination of Giemsa-stained blood sme...The objective of this study was to investigate the epidemiology of bovine Piroplasms infections in the Rasǒn area of North Korea.The survey was carried out by light microscopic examination of Giemsa-stained blood smears,PCR,and phylogenetic evolution analysis of 128 blood samples collected from the Rasǒn area.The results showed that the infection rates of the small and large parasites were about 2.5 and 1.5% on average,respectively,in all Theileria sergenti and Babesia ovatapositive blood smears by microscopic examination of blood smears.The detection rate of T.sergenti Giemsa-stained smears was 43.75%,while that with PCR was 67.97%.The detection rate of B.ovata Giemsa-stained smears was 49.21%,while that with PCR was 71.88%.The sequence and phylogenetic analysis of DNA showed 98.84% homology between the 18S rRNA gene sequences of T.sergenti isolates from North Korean and that of Yanbian state from China,indicating the closest genetic relationship between both of them.Moreover,100% homology was shown between the 18S rRNA gene sequence of B.ovata isolates from North Korea and the published sequence AY081192 of GenBank,indicating the closest genetic relationship between both of them.This survey confirmed that Ras n is the endemic area of T.sergenti and B.ovata in North Korea.展开更多
The 2nd U.S.-North Korea Summit between U.S.President Donald Trump and North Korean leader Kim Jong Un was held in Hanoi,Vietnam on February 27 and 28,2019.However,no agreement was made despite high expectations befor...The 2nd U.S.-North Korea Summit between U.S.President Donald Trump and North Korean leader Kim Jong Un was held in Hanoi,Vietnam on February 27 and 28,2019.However,no agreement was made despite high expectations before the summit.The author of this paper,who was involved in the press conference following the summit as an interpreter for a Japanese TV program in Tokyo,recognized that Trump,who often criticizes some media outlets,calling them“fake news”,handled the press respectfully.To answer the question why there is a gap between his attitudes toward various media outlets,this paper examines the interactions between the president and all 21 reporters who were allowed to ask him questions during the Hanoi press conference,focusing on their questions,the organizations they belonged to,and some personal details.President Trump’s extremely well-calculated media strategy is then revealed.展开更多
The use of sanctions to coerce Pyongyang into abandoning its nuclear weapons and related programs is not working. North Korea continues to survive and expands its nuclear and missile capabilities. It is time for the U...The use of sanctions to coerce Pyongyang into abandoning its nuclear weapons and related programs is not working. North Korea continues to survive and expands its nuclear and missile capabilities. It is time for the US to construct a more successful North Korea strategy by applying a smart power strategy before the North Koreans can operationalize their nuclear ICBMs within the next several years. If and when that occurs, the US will inevitably consider the use of force to resolve the North Korean nuclear issue, but that will be too costly for the US and its allies. Washington must do all it can to avoid another war on the Asian mainland. The only practical uses of force are as defensive and enhanced deterrence measures to protect the US and its allies against North Korean nuclear and conventional provocations. Instead, the US should call for an immediate freeze of North Korea＇s nuclear and missile programs and demonstrate its willingness to co-exist with Pyongyang, Only by accepting co-existence with Pyongyang, Washington has an opportunity to persuade Beijing and Moscow to join its efforts with Seoul and Tokyo to denuclearize North Korea. It is time to engage North Korea by accepting it as it is and exercising strategic patience of a different kind to achieve US aims.展开更多
The calling activity of anurans is influenced by environmental variables and calls produced by syntopic amphibians,among other variables.Some variables have a strong influence,such as temperature and predation dilutio...The calling activity of anurans is influenced by environmental variables and calls produced by syntopic amphibians,among other variables.Some variables have a strong influence,such as temperature and predation dilution,while others may have a periodical influence such as the moon cycle.Here,we hypothesised that the calling activity of the Suweon treefrog,Dryophytes suweonensis,is restricted by specific environmental variables but reinforced by the calling activity of specific syntopic anurans.Within the criteria set by the experimental design,D.suweonensis calling activity was significantly influenced by moon phase,temperature,date,time to sunset and the calling activity of Pelophylax nigromaculatus and D.japonicus.These variables are expected to be related to chorus size,predation,breeding phenology and competition,suggesting a broad plasticity in the calling activity of the species.展开更多
Located on the border of Jilin Province of China and Samjiyon County under Ryanggang Province of North Korea,Changbai Mountain is adjacent to the southeast North Korea.Changbai Mountain is also called Beakdu Mountain ...Located on the border of Jilin Province of China and Samjiyon County under Ryanggang Province of North Korea,Changbai Mountain is adjacent to the southeast North Korea.Changbai Mountain is also called Beakdu Mountain because of the white pumice stones and snow accumulation on its peak.As the highest mountain in the northeast,Changbai Mountain is known as the“Ridge of Northeast”.展开更多
文摘The North Korea nuclear challenge,urgent on the US foreign policy agenda since Donald Trump took office,has prompted unilateral,bilateral and multilateral moves to address rising tension on the peninsula.The underlying logic of US policy,which in November placed the DPRK back on the list of state sponsors of terrorism,promotes negotiation by imposing Maximum Pressure and by enlisting China's support.Possibly,North Korea will return to negotiations with its nuclear and missile development suspended temporarily.Other possibilities are a stalemate with North Korea joining the ranks of countries with credible nuclear deterrent,or an emerging crisis that escalates to military or other conflict.The lingering uncertainty is central to northeast Asia security.
基金Under the auspices of Key Deployment Project of Chinese Academy of Sciences(No.KZZD-EW-08-02)
文摘Studies on long-term change of cropland is of great significance to the utilization of land resources and the implementation of scientific agricultural policies. The Korean Peninsula, adjacent to China, plays an important role in the international environment of Northeast Asia. The Korean Peninsula includes South Korea and North Korea—two countries that have a great difference in their institutions and economic developments. Therefore, we aim to quantify the spatiotemporal changes of croplands in these two countries using Landsat Thematic Imager(TM) and Operational Land Imager(OLI) imagery, and to compare the differences of cropland changes between the two countries. This paper take full advantage of ODM approach(object-oriented segmentation and decision-tree classification based on multi-season imageries) to obtain the distribution of croplands in 1990 and 2015. Results showed that the overall classification accuracy of cropland data is 91.10% in 1990 and 92.52% in 2015. The croplands were mainly distributed in areas with slopes that were less than 8° and with elevations that were less than 300 m in the Korean Peninsula. However, in other region(slope > 8° or elevation > 300 m), the area and proportion of North Korea's croplands were significantly higher than that of South Korea. Croplands significantly increased by 15.02% in North Korea from 1990 to 2015. In contrast, croplands in South Korea slightly decreased by 1.32%. During the 25 years, policy shift, economic development, population growth, and urban sprawl played primary roles for cropland changes. Additionally, the regional differences of cropland changes were mainly due to different agriculture policies implemented by different countries. The achievements of this study can provide scientific guidance for the protection and sustainability of land resources.
文摘Bases on studies of bryophytes collecled by Cao Tong in August 1997 from North Kolea, 81 species belonging to 52 genera, 26 families of mosses and 16 species belonging to 12 genera, 10 families of hepatics are recorded. Among these, 6 rpeciec and 1 form are new to bryoflora of the Korean Peninsula. These are : Campylopus gracilis (Mitt.) Jaeg.,Grimmia leavigata (Brid.) Brid., Okamura hakoniensis f. mutiflagellifera (Okam.) Nog., Orthotrchum erubescens C. Muell.,Scapania verrucosa Heeg., Schistidum strictum (Turn.) Loeske ex O. Maort. and Schistidium subconfertum (Broth.)Deguchi.
基金supported by the National Institute of Forest Science(Project No.FM0800-2019-05)。
文摘Due to considerable deforestation in North Korea,there is a need to plan forest restoration programs based on scientific forest management.In this study,a methodology was developed for estimating the site index values of six major tree species and the forest productivity potential.The site index values of these tree species were derived in South Korea using the Chapman-Richards equation.These values were used with data from the 6th National Forest Inventory,which included 20 types of edaphic,topographic,and climatic factors,and random forest analysis—a widely used machine learning technique for spatial prediction—to develop a new model for estimating the site index values of these species across South Korea.The prediction accuracy of this model was evaluated using the root mean square error.The results show that the prediction accuracy was high,with a root mean square error of~1m.Moreover,the importance of the variables related to climate and geography was generally high.The proposed site index estimation model for six tree species was applied across North Korea,and its effectiveness tested by comparing the estimated values with those reported in literature from North Korea.The differences between the model outputs and recorded data in the northern alpine regions were presumably due to the lack of data for high-altitude regions in South Korea.This model is based on the determination of the suitability of tree species in restoration efforts.Therefore,it can contribute to the evaluation of forest productivity in North Korea and may help plan efficient forest restoration programs.
基金supported by the National Natural Science Foundation of China (30560112, 30960278)Natural Science Foundation of Jilin Province of China (201115230)
文摘The objective of this study was to investigate the epidemiology of bovine Piroplasms infections in the Rasǒn area of North Korea.The survey was carried out by light microscopic examination of Giemsa-stained blood smears,PCR,and phylogenetic evolution analysis of 128 blood samples collected from the Rasǒn area.The results showed that the infection rates of the small and large parasites were about 2.5 and 1.5% on average,respectively,in all Theileria sergenti and Babesia ovatapositive blood smears by microscopic examination of blood smears.The detection rate of T.sergenti Giemsa-stained smears was 43.75%,while that with PCR was 67.97%.The detection rate of B.ovata Giemsa-stained smears was 49.21%,while that with PCR was 71.88%.The sequence and phylogenetic analysis of DNA showed 98.84% homology between the 18S rRNA gene sequences of T.sergenti isolates from North Korean and that of Yanbian state from China,indicating the closest genetic relationship between both of them.Moreover,100% homology was shown between the 18S rRNA gene sequence of B.ovata isolates from North Korea and the published sequence AY081192 of GenBank,indicating the closest genetic relationship between both of them.This survey confirmed that Ras n is the endemic area of T.sergenti and B.ovata in North Korea.
文摘The 2nd U.S.-North Korea Summit between U.S.President Donald Trump and North Korean leader Kim Jong Un was held in Hanoi,Vietnam on February 27 and 28,2019.However,no agreement was made despite high expectations before the summit.The author of this paper,who was involved in the press conference following the summit as an interpreter for a Japanese TV program in Tokyo,recognized that Trump,who often criticizes some media outlets,calling them“fake news”,handled the press respectfully.To answer the question why there is a gap between his attitudes toward various media outlets,this paper examines the interactions between the president and all 21 reporters who were allowed to ask him questions during the Hanoi press conference,focusing on their questions,the organizations they belonged to,and some personal details.President Trump’s extremely well-calculated media strategy is then revealed.
文摘The use of sanctions to coerce Pyongyang into abandoning its nuclear weapons and related programs is not working. North Korea continues to survive and expands its nuclear and missile capabilities. It is time for the US to construct a more successful North Korea strategy by applying a smart power strategy before the North Koreans can operationalize their nuclear ICBMs within the next several years. If and when that occurs, the US will inevitably consider the use of force to resolve the North Korean nuclear issue, but that will be too costly for the US and its allies. Washington must do all it can to avoid another war on the Asian mainland. The only practical uses of force are as defensive and enhanced deterrence measures to protect the US and its allies against North Korean nuclear and conventional provocations. Instead, the US should call for an immediate freeze of North Korea＇s nuclear and missile programs and demonstrate its willingness to co-exist with Pyongyang, Only by accepting co-existence with Pyongyang, Washington has an opportunity to persuade Beijing and Moscow to join its efforts with Seoul and Tokyo to denuclearize North Korea. It is time to engage North Korea by accepting it as it is and exercising strategic patience of a different kind to achieve US aims.
基金financially supported by research grants from the National Research Foundation of Korea (2017R1A2B2003579)the Rural Development Administration (PJ012285) to Y JANGa grant from the French Rotary Club Lectoure-Fleurance to A Borzée。
文摘The calling activity of anurans is influenced by environmental variables and calls produced by syntopic amphibians,among other variables.Some variables have a strong influence,such as temperature and predation dilution,while others may have a periodical influence such as the moon cycle.Here,we hypothesised that the calling activity of the Suweon treefrog,Dryophytes suweonensis,is restricted by specific environmental variables but reinforced by the calling activity of specific syntopic anurans.Within the criteria set by the experimental design,D.suweonensis calling activity was significantly influenced by moon phase,temperature,date,time to sunset and the calling activity of Pelophylax nigromaculatus and D.japonicus.These variables are expected to be related to chorus size,predation,breeding phenology and competition,suggesting a broad plasticity in the calling activity of the species.
文摘Located on the border of Jilin Province of China and Samjiyon County under Ryanggang Province of North Korea,Changbai Mountain is adjacent to the southeast North Korea.Changbai Mountain is also called Beakdu Mountain because of the white pumice stones and snow accumulation on its peak.As the highest mountain in the northeast,Changbai Mountain is known as the“Ridge of Northeast”.
