Pub Date : 2021-04-01DOI: 10.3741/JKWRA.2021.54.4.255
K. Baek
Mixing characteristics of the longitudinal/transverse directions is inevitably different in rivers with a large aspect ratio. Particularly complex mixing behavior occurs in the area of the confluence where tributaries and main streams of different concentrations meet, and it is necessary to accurately implement such mixing characteristics by assigning appropriate values of longitudinal and transverse dispersion coefficients. In this study, the mixing behavior according to the different values in the longitudinal/transverse dispersion coefficient was analyzed by using the two-dimensional model (RAMS) at the confluence where three rivers (the Nakdong River, the Geumho River, and the Jincheon Creek) meet. Firstly the longitudinal and transverse dispersion coefficients were calibrated and validated based on the electrical conductivity (EC) acquired from field measurements. Through the calibration and validation, it was shown that the longitudinal dispersion coefficient was about 25 times larger than the transverse dispersion coefficient in this area. Then assuming that a hazardous substance (phenol) was introduced into the upper boundaries of the Geumho River and the Jincheon Creek due to an accidental spill, the concentration of phenol arrived at the water intake facilities was calculated by using the calibrated numerical model. As a result, characteristics such as time and peak concentration of hazardous substances reaching the water intake facilities were very different according to the ratio of the longitudinal/transverse dispersion coefficient values. In fact, this is an example that the selection of the dispersion coefficients can affect decision-making such as stopping water intake during an appropriate time at the facilities, when if phenol is introduced into a river. In the end, when using a two-dimensional mixing model in a river, it was confirmed that the provision of an appropriate value of the longitudinal/transverse dispersion coefficient was an important factor.
{"title":"Evaluation of longitudinal / transverse dispersion coefficients and prediction of concentration at river confluence in two-dimensional solute transport analysis","authors":"K. Baek","doi":"10.3741/JKWRA.2021.54.4.255","DOIUrl":"https://doi.org/10.3741/JKWRA.2021.54.4.255","url":null,"abstract":"Mixing characteristics of the longitudinal/transverse directions is inevitably different in rivers with a large aspect ratio. Particularly complex mixing behavior occurs in the area of the confluence where tributaries and main streams of different concentrations meet, and it is necessary to accurately implement such mixing characteristics by assigning appropriate values of longitudinal and transverse dispersion coefficients. In this study, the mixing behavior according to the different values in the longitudinal/transverse dispersion coefficient was analyzed by using the two-dimensional model (RAMS) at the confluence where three rivers (the Nakdong River, the Geumho River, and the Jincheon Creek) meet. Firstly the longitudinal and transverse dispersion coefficients were calibrated and validated based on the electrical conductivity (EC) acquired from field measurements. Through the calibration and validation, it was shown that the longitudinal dispersion coefficient was about 25 times larger than the transverse dispersion coefficient in this area. Then assuming that a hazardous substance (phenol) was introduced into the upper boundaries of the Geumho River and the Jincheon Creek due to an accidental spill, the concentration of phenol arrived at the water intake facilities was calculated by using the calibrated numerical model. As a result, characteristics such as time and peak concentration of hazardous substances reaching the water intake facilities were very different according to the ratio of the longitudinal/transverse dispersion coefficient values. In fact, this is an example that the selection of the dispersion coefficients can affect decision-making such as stopping water intake during an appropriate time at the facilities, when if phenol is introduced into a river. In the end, when using a two-dimensional mixing model in a river, it was confirmed that the provision of an appropriate value of the longitudinal/transverse dispersion coefficient was an important factor.","PeriodicalId":224359,"journal":{"name":"Journal of Korea Water Resources Association","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122215214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-04-01DOI: 10.3741/JKWRA.2021.54.4.229
S. Chae
This study projected the monthly precipitation for RCP4.5 and RCP8.5 of the MIROC5 and SSP2-4.5 and SSP5-8.5 of MIROC6 GCMs using observations of the historical period (1970 to 2005) of 21 stations in Korea, and then compared the performance before and after bias correction using 6 evaluation indicators. In addition, using the bias corrected GCM’s scenarios, annual precipitation, summer precipitation and winter precipitation in near future period (2021-2060) and far future period (2061-2100) were calculated. Furthermore, the variability of future projection was quantified using the standard deviation and interquartile range values of future precipitation. As a result the rate of change of precipitation was greater in the northern region than in the southern region and in the far future rather than the near future. The variability in the projection were also concluded to be larger in the northern region than that in the southern regions.
{"title":"Comparison of MIROC5 and MIROC6 projections for precipitation over South Korea","authors":"S. Chae","doi":"10.3741/JKWRA.2021.54.4.229","DOIUrl":"https://doi.org/10.3741/JKWRA.2021.54.4.229","url":null,"abstract":"This study projected the monthly precipitation for RCP4.5 and RCP8.5 of the MIROC5 and SSP2-4.5 and SSP5-8.5 of MIROC6 GCMs using observations of the historical period (1970 to 2005) of 21 stations in Korea, and then compared the performance before and after bias correction using 6 evaluation indicators. In addition, using the bias corrected GCM’s scenarios, annual precipitation, summer precipitation and winter precipitation in near future period (2021-2060) and far future period (2061-2100) were calculated. Furthermore, the variability of future projection was quantified using the standard deviation and interquartile range values of future precipitation. As a result the rate of change of precipitation was greater in the northern region than in the southern region and in the far future rather than the near future. The variability in the projection were also concluded to be larger in the northern region than that in the southern regions.","PeriodicalId":224359,"journal":{"name":"Journal of Korea Water Resources Association","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130189818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-04-01DOI: 10.3741/JKWRA.2021.54.4.265
Jingyeom Kim
The Hwanggang Dam in North Korea is located upstream of the Imjin River which is a shared river on the border. It is known to have a reservoir capacity of 350 million cubic meters, which is about 1.5 times larger than Paldang Dam in South Korea, and releases a discharge largely for generating hydroelectric power and partly for transferring to the Yesung River basin. Due to the special national security issues in the region, data sharing between the south and north Koreas is not made, and flood damage risk due to heavy storm and unauthorized discharge is remained in the south Korean-side downstream region. However, It is still difficult to forecast the flood because the operating information of the Hwanggang Dam is not shared. In this study, a dam inflow and reservoir water level change modeling system was constructed using lumped hydrological model and reservoir operation algorithm based on AutoROM. Dam inflow was verified indirectly using remotely sensed water level derived by Sentinel-2 optical satellite and 10m high-resolution terrain map. Coefficient of determination (R2) derived as 0.76 for water level changing from Jan. 2017 to Aug. 2020.
{"title":"Estimation of ungauged Hwanggang dam inflow using Sentinel-2 optical satellite imagery","authors":"Jingyeom Kim","doi":"10.3741/JKWRA.2021.54.4.265","DOIUrl":"https://doi.org/10.3741/JKWRA.2021.54.4.265","url":null,"abstract":"The Hwanggang Dam in North Korea is located upstream of the Imjin River which is a shared river on the border. It is known to have a reservoir capacity of 350 million cubic meters, which is about 1.5 times larger than Paldang Dam in South Korea, and releases a discharge largely for generating hydroelectric power and partly for transferring to the Yesung River basin. Due to the special national security issues in the region, data sharing between the south and north Koreas is not made, and flood damage risk due to heavy storm and unauthorized discharge is remained in the south Korean-side downstream region. However, It is still difficult to forecast the flood because the operating information of the Hwanggang Dam is not shared. In this study, a dam inflow and reservoir water level change modeling system was constructed using lumped hydrological model and reservoir operation algorithm based on AutoROM. Dam inflow was verified indirectly using remotely sensed water level derived by Sentinel-2 optical satellite and 10m high-resolution terrain map. Coefficient of determination (R2) derived as 0.76 for water level changing from Jan. 2017 to Aug. 2020.","PeriodicalId":224359,"journal":{"name":"Journal of Korea Water Resources Association","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130203881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-04-01DOI: 10.3741/JKWRA.2021.54.4.217
Taeuk Kang
Baseflow constitutes most of the streamflow during the dry season and it is an important factor for stream management. In this study, four techniques for separating baseflow from the streamflow were applied to two target areas to examine the applicability. The baseflow separation techniques used in the analysis are all graphical methods, which are fixed interval method (FIM), sliding interval method (SIM), local minimum method (LMM), and PART programs based on the N-day method. The target areas are the Daeri and Cheongsong stage stations in the Nakdong River Basin where the streamflow was measured continuously for 5 years. We evaluated the appropriateness of the results for baseflow separation methods by examining the indexes for model assessment (NSE, PBIAS, RSR), baseflow index, and shape of baseflow separated from a flood hydrograph. It was analyzed that the FIM, SIM, and LMM methods included some errors in separating the baseflow from streamflow, whereas the PART program results were found to be the best.
{"title":"Case study on application of graphical method for baseflow separation","authors":"Taeuk Kang","doi":"10.3741/JKWRA.2021.54.4.217","DOIUrl":"https://doi.org/10.3741/JKWRA.2021.54.4.217","url":null,"abstract":"Baseflow constitutes most of the streamflow during the dry season and it is an important factor for stream management. In this study, four techniques for separating baseflow from the streamflow were applied to two target areas to examine the applicability. The baseflow separation techniques used in the analysis are all graphical methods, which are fixed interval method (FIM), sliding interval method (SIM), local minimum method (LMM), and PART programs based on the N-day method. The target areas are the Daeri and Cheongsong stage stations in the Nakdong River Basin where the streamflow was measured continuously for 5 years. We evaluated the appropriateness of the results for baseflow separation methods by examining the indexes for model assessment (NSE, PBIAS, RSR), baseflow index, and shape of baseflow separated from a flood hydrograph. It was analyzed that the FIM, SIM, and LMM methods included some errors in separating the baseflow from streamflow, whereas the PART program results were found to be the best.","PeriodicalId":224359,"journal":{"name":"Journal of Korea Water Resources Association","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130137197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-04-01DOI: 10.3741/JKWRA.2021.54.4.241
Ock-Jae Jang
Drought is a natural disaster which is hard to recognize its onset and termination and to estimate the damage from the events which occurred in the past and are expected in near future. While the drought indices or their frequencies are widely applied to explain the severity of each event in the existing studies, decision-makers and stakeholders (the public) may have trouble in understanding the results due to the unfamiliar expression with statistical values. In this study, therefore, the methodology for assessment and forecast of drought severity based on the amount of water shortage from the water balance analysis was be placed at the center of the discussion. Firstly, in order to improve the existing analysis for drought assessment adopted in the National Water Resources Plan, alternative methods have been suggested to estimate the amount of water demand in each sub-basin using the land use map, and in an aspect of water supply, reservoirs and underground water are included in the simulation of MODSIM-DSS. The relationship between drought severity from the simulated water shortage in the study area and the values of SPEIs (SPEI 6 = estimated for 6 months winter and spring season, SPEI 3 = estimated for 3 months summer season) has been analyzed by the Decision tree. Due to this achievement, at the end of the spring season, every year the forecast for the drought severity will be available with the quantitatively estimated water shortage, and it will be helpful to activate the drought mitigation measures before the disaster occurs.
{"title":"Methodology for assessment and forecast of drought severity based on the water balance analysis","authors":"Ock-Jae Jang","doi":"10.3741/JKWRA.2021.54.4.241","DOIUrl":"https://doi.org/10.3741/JKWRA.2021.54.4.241","url":null,"abstract":"Drought is a natural disaster which is hard to recognize its onset and termination and to estimate the damage from the events which occurred in the past and are expected in near future. While the drought indices or their frequencies are widely applied to explain the severity of each event in the existing studies, decision-makers and stakeholders (the public) may have trouble in understanding the results due to the unfamiliar expression with statistical values. In this study, therefore, the methodology for assessment and forecast of drought severity based on the amount of water shortage from the water balance analysis was be placed at the center of the discussion. Firstly, in order to improve the existing analysis for drought assessment adopted in the National Water Resources Plan, alternative methods have been suggested to estimate the amount of water demand in each sub-basin using the land use map, and in an aspect of water supply, reservoirs and underground water are included in the simulation of MODSIM-DSS. The relationship between drought severity from the simulated water shortage in the study area and the values of SPEIs (SPEI 6 = estimated for 6 months winter and spring season, SPEI 3 = estimated for 3 months summer season) has been analyzed by the Decision tree. Due to this achievement, at the end of the spring season, every year the forecast for the drought severity will be available with the quantitatively estimated water shortage, and it will be helpful to activate the drought mitigation measures before the disaster occurs.","PeriodicalId":224359,"journal":{"name":"Journal of Korea Water Resources Association","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134111335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-01DOI: 10.3741/JKWRA.2021.54.3.181
Dongwook Ko
{"title":"Application of 3D point cloud modeling for performance analysis of reinforced levee with biopolymer","authors":"Dongwook Ko","doi":"10.3741/JKWRA.2021.54.3.181","DOIUrl":"https://doi.org/10.3741/JKWRA.2021.54.3.181","url":null,"abstract":"","PeriodicalId":224359,"journal":{"name":"Journal of Korea Water Resources Association","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116278626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-01DOI: 10.3741/JKWRA.2021.54.3.145
Dongwook Kim
{"title":"Evaluating meteorological and hydrological impacts on forest fire occurrences using partial least squares-structural equation modeling: a case of Gyeonggi-do","authors":"Dongwook Kim","doi":"10.3741/JKWRA.2021.54.3.145","DOIUrl":"https://doi.org/10.3741/JKWRA.2021.54.3.145","url":null,"abstract":"","PeriodicalId":224359,"journal":{"name":"Journal of Korea Water Resources Association","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131887504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-01DOI: 10.3741/JKWRA.2021.54.3.157
Heechan Han
{"title":"Application of sequence to sequence learning based LSTM model (LSTM-s2s) for forecasting dam inflow","authors":"Heechan Han","doi":"10.3741/JKWRA.2021.54.3.157","DOIUrl":"https://doi.org/10.3741/JKWRA.2021.54.3.157","url":null,"abstract":"","PeriodicalId":224359,"journal":{"name":"Journal of Korea Water Resources Association","volume":"503 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123422610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-01DOI: 10.3741/JKWRA.2021.54.3.203
Taesun Lee
In the present study, hydrologic data and topographical data from 2010 to 2019 were collected from three gauging stations placed in the watershed of Naeseong stream to determine changes and rates of changes in rainfall, water level & mean velocity, and water level & discharge, together with changes in rates of erosion and deposition at cross-sections of the river. Besides, effects of regulated and non-regulated rivers according to the presence of artificial regulation of flow rate of the river via artificial structure located at Seo stream (Yeongju si (Wolhogyo) station), the tributary free from construction of dams, were compared and analyzed. Results of analyses conducted in the present study revealed vegetational establishment and landforming due to increasing area of vegetational sandbar evolved in the flood plain (intermediateor highwater level) by the drought sustained from 2013 to 2015. Continuous erosion of river bed was appeared because of narrowed flow area with low water level and increased velocity and tractive force on river bed.
{"title":"Analysis of changes in cross section and flow rate due to vegetation establishment in Naeseong stream","authors":"Taesun Lee","doi":"10.3741/JKWRA.2021.54.3.203","DOIUrl":"https://doi.org/10.3741/JKWRA.2021.54.3.203","url":null,"abstract":"In the present study, hydrologic data and topographical data from 2010 to 2019 were collected from three gauging stations placed in the watershed of Naeseong stream to determine changes and rates of changes in rainfall, water level & mean velocity, and water level & discharge, together with changes in rates of erosion and deposition at cross-sections of the river. Besides, effects of regulated and non-regulated rivers according to the presence of artificial regulation of flow rate of the river via artificial structure located at Seo stream (Yeongju si (Wolhogyo) station), the tributary free from construction of dams, were compared and analyzed. Results of analyses conducted in the present study revealed vegetational establishment and landforming due to increasing area of vegetational sandbar evolved in the flood plain (intermediateor highwater level) by the drought sustained from 2013 to 2015. Continuous erosion of river bed was appeared because of narrowed flow area with low water level and increased velocity and tractive force on river bed.","PeriodicalId":224359,"journal":{"name":"Journal of Korea Water Resources Association","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132772444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-01DOI: 10.3741/JKWRA.2021.54.3.191
Jongyun Na
Rivers have been damaged due to rapid urbanization, and river management has been carried out focusing on flow and flood control functions. Recently, interest in river restoration, emphasizing the environmental aspects of rivers, is increasing, but the beginning of river restoration requires an appropriate evaluation of the environmental flow required for the ecosystem. This study analyzed the effects on the habitat of the river ecosystem by estimating the changes in flow regime and environmental flow following the construction of the Buhang dam in Gamcheon, the first tributary of the Nakdong River. To evaluate the environmental flow, the dominant species of Gamcheon, Zacco Platypus, and the protected species Squalidus gracilis majime, and riparian vegetation were selected, and the environmental flow was calculated using the HEC-EFM (Ecosystem Function Model). The evaluated environmental flow was linked with hydraulic analysis and GIS platform, and habitat area change and habitat connectivity analysis before and after dam construction were performed by spatial habitat analysis in the river. Based on the results of this study, it can be used as a river restoration project and a dam operation plan considering the river environment through the calculation of environmental flow and habitat connectivity analysis to improve the habitat of the river ecosystem.
{"title":"Assessment of the environmental flow and habitat of the river ecosystem through ecosystem function model","authors":"Jongyun Na","doi":"10.3741/JKWRA.2021.54.3.191","DOIUrl":"https://doi.org/10.3741/JKWRA.2021.54.3.191","url":null,"abstract":"Rivers have been damaged due to rapid urbanization, and river management has been carried out focusing on flow and flood control functions. Recently, interest in river restoration, emphasizing the environmental aspects of rivers, is increasing, but the beginning of river restoration requires an appropriate evaluation of the environmental flow required for the ecosystem. This study analyzed the effects on the habitat of the river ecosystem by estimating the changes in flow regime and environmental flow following the construction of the Buhang dam in Gamcheon, the first tributary of the Nakdong River. To evaluate the environmental flow, the dominant species of Gamcheon, Zacco Platypus, and the protected species Squalidus gracilis majime, and riparian vegetation were selected, and the environmental flow was calculated using the HEC-EFM (Ecosystem Function Model). The evaluated environmental flow was linked with hydraulic analysis and GIS platform, and habitat area change and habitat connectivity analysis before and after dam construction were performed by spatial habitat analysis in the river. Based on the results of this study, it can be used as a river restoration project and a dam operation plan considering the river environment through the calculation of environmental flow and habitat connectivity analysis to improve the habitat of the river ecosystem.","PeriodicalId":224359,"journal":{"name":"Journal of Korea Water Resources Association","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131385225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：