• Title/Summary/Keyword: environmental changes

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Evaluation of Space-based Wetland InSAR Observations with ALOS-2 ScanSAR Mode (습지대 변화 관측을 위한 ALOS-2 광대역 모드 적용 연구)

  • Hong, Sang-Hoon;Wdowinski, Shimon
    • Korean Journal of Remote Sensing
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    • v.38 no.5_1
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    • pp.447-460
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    • 2022
  • It is well known that satellite synthetic aperture radar interferometry (InSAR) has been widely used for the observation of surface displacement owing to earthquakes, volcanoes, and subsidence very precisely. In wetlands where vegetation exists on the surface of the water, it is possible to create a water level change map with high spatial resolution over a wide area using the InSAR technique. Currently, a number of imaging radar satellites are in operation, and most of them support a ScanSAR mode observation to gather information over a large area at once. The Cienaga Grande de Santa Marta (CGSM) wetland, located in northern Colombia, is a vast wetland developed along the Caribbean coast. The CGSM wetlands face serious environmental threats from human activities such as reclamation for agricultural uses and residential purposes as well as natural causes such as sea level rise owing to climate change. Various restoration and protection plans have been conducted to conserve these invaluable environments in recognition of the ecological importance of the CGSM wetlands. Monitoring of water level changes in wetland is very important resources to understand the hydrologic characteristics and the in-situ water level gauge stations are usually utilized to measure the water level. Although it can provide very good temporal resolution of water level information, it is limited to fully understand flow pattern owing to its very coarse spatial resolution. In this study, we evaluate the L-band ALOS-2 PALSAR-2 ScanSAR mode to observe the water level change over the wide wetland area using the radar interferometric technique. In order to assess the quality of the interferometric product in the aspect of spatial resolution and coherence, we also utilized ALOS-2 PALSAR-2 stripmap high-resolution mode observations.

The Interrelationship between Riparian Vegetation and Hydraulic Characteristics during the 2020 Summer Extreme Flood in the Seomjin-gang River, South Korea (2020 여름 섬진강 대홍수시 하안식생과 수리 특성의 상호관계)

  • Lee, Cheolho;Lee, Keonhak;Kim, Hwirae;Baek, Donghae;Kim, Won;Kim, Daehyun;Lee, Hyunjae;Woo, Hyoseop;Cho, Kang-Hyun
    • Ecology and Resilient Infrastructure
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    • v.8 no.2
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    • pp.79-87
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    • 2021
  • Because active interactions occur among vegetation, hydrology, and geomorphology in riparian systems, any changes in one of these factors can significantly affect the other two. In this study, we evaluated these interactions at four sites (two in Gajeong and two in Hahan) along the Seomjin-gang River that was substantially devastated by an extreme flood in 2020. We examined the relationship between the riparian vegetation and the hydraulic characteristics of the flood using remote sensing, hydraulic modeling, and field surveys combined. The evaluation results showed that the floods caused a record-breaking rise of up to 43.1 m above sea level at the Yeseong-bridge stage gauge station (zero elevation 27.4 m) located between the Gajeong and Hahan sites, with the shear stress being four times higher in Hahan than in Gajeong. Additionally, the water level during the flood was estimated to be a maximum of 1 m higher depending on the location in the presence of riparian plants. Furthermore, both sites underwent extensive biological damage due to the flood, with 78-80% loss in vegetation, with preferential damage observed in large willow species, compared to Quercus acutissima. The above findings imply that all plant species exhibit different vulnerabilities towards extreme floods and do not induce similar behavior towards events causing a disturbance. In conclusion, we developed strategies for effectively managing riparian trees by minimizing flood hazards that could inevitably cause damage.

Evaluation of Rice Protein Content Variation on Cultivation and Environmental Conditions (재배 및 환경조건에 따른 쌀 단백질 함량 변동 평가 )

  • Yun-Ho, Lee;Jeong-Won, Kim;Jae-Hyeok, Jeong;Woon-Ha, Hwang;Hyeon-Seok, Lee;Seo-Yeong, Yang;Chung-Keun, Lee
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.24 no.4
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    • pp.267-274
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    • 2022
  • The effect of year, varieties, nitrogen application, and transplant time were examined in relation to rice of protein. An experiment was conducted using 12 rice varieties to investigate the effect of management and weather conditions on brown rice protein of during the filling stage. The transplanting time was set to be three groups including early, medium, and late timing. The nitrogen application was set to be 0 N kg / 10a, 9N kg / 10a and 18 N kg / 10a to examine the effect of fertilizer management on protein content. Field experiments were conducted in three growing seasons including 2019, 2020, and 2021. The brown rice of protein content were 5.7%, 5.9%, and 6.6% under early, medium, and late transplanting time conditions, respectively. The protein content differ by variety. For example, Chucheong, Hopum, Ilpum, Mipum, Odae, Saenuri, and Saeilmi had more than 6.1%, and Chindeul, Shindongjin, Samkwang, Unkwang, Younhojinmi were less than 6.1%. Nitrogen content was 5.7% for 0kgN /10a, 6.1% for 9kgN /10a, and 6.8% for 18kgN /10a. The contribution of the characteristics to the protein content was highest in nitrogen content (38.8%), followed by transplanting time (13.7%), variety (8.2%), and year (3.5%). The average temperature for 20 days after heading time was the highest (9.3%), followed by sunshine duration (3.9%) and solar radiation (3.5%). Our results revealed that brown rice protein content was determined to be affected by changes in average temperature, sunshine duration and solar radiation for 20 days after heading time. This suggested that assessment of temperature and solar radiation after heading time would indicate the degree of rice quality in terms of protein.

An Exploratory Study of Professionalism on Data Management Jobs in the Public Sector: From the Perspective of Library and Information Science (공공부문 데이터 관리직무의 전문성에 대한 탐색적 연구 - 문헌정보학 관점에서 -)

  • Heejin, Park;Ji Sung, Kim
    • Journal of the Korean Society for Library and Information Science
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    • v.56 no.4
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    • pp.491-514
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    • 2022
  • Public reforms based on New Public Management have made the public sector specialized, and accordingly the role of public administration has expanded as well as the demand on professional jobs has increased. On the other hand, with the rapid development of information and communication technology, the data produced by public sector organizations has also significantly increased. This environmental changes made data management and a data management job in the public sector critical. However, there have been very few studies of conceptualizations and systematic investigations on data management jobs. Moreover, specific definitions, types or qualifications of/for a data management job or a person who do this job are rarely reflected in relevant laws and regulations. Based on the systematic literature review, this study conceptualized professionalism, identified its multiple dimensions, and draw a conceptual research framework. Focusing on the professional control on personnel management which is one of the dimensions of professionalism, relevant laws, work guidelines and job descriptions included in job openings were analyzed with regard to a data management job in the public sector. The findings are as follows. First, an assigned role and responsibility associated with a data management job have vague boundaries. Second, work guidelines and manuals only focus on the post quality control stage rather than equally addressing all the eight stages of the data lifecycle. Third, neither a data management job in the public sector nor a person who take care of this job is not appropriately defined. Therefore, a role and responsibility of/for the job and a person in charge should be reflected in the relevant laws and guidelines in a tailored way. More importantly, job analyses and evaluations should be thoroughly conducted to enhance professionalism on data management jobs in the long term.

Changes in the Linear Compressibility and Bulk Modulus of Natural Stilbite Under Pressure with Varying Pressure-Transmitting Media (천연 스틸바이트의 압력전달매개체에 따른 선형압축률 및 체적탄성률 비교 연구)

  • Hwang, Huijeong;Lee, Hyunseung;Lee, Soojin;Jung, Jaewoo;Lee, Yongmoon
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.3
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    • pp.367-376
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    • 2022
  • This study is a preliminary step to understand the reaction between various liquids and zeolite in the subduction zone environment. Stilbite, NaCa4(Al9Si27)O72·28(H2O), was selected and high pressure study was conducted on compressional behavior by the pressure-transmitting medium (PTM). Water and NaHCO3 solution that can exist in the subduction zone was used as PTM, and samples were pressurized from ambient to a maximum of 2.5 GPa. Below 1.0 GPa, both experiments show a low linear compressibility in the range of 0.001 to 0.004 GPa-1 and a high bulk modulus of 220(1) GPa. This is presumably because the structure of the stilbite becomes very dense due to insertion of water molecules or cations into the channel. On the other hand, at 1.0 GPa or higher, the trends of the two experiments are different. In the water run, the linear compressibility of the c-axis is increased to 0.006(1) GPa-1. In the NaHCO3 run, the linear compressibility of the b- and c-axis is increased to 0.006(1) GPa-1. The bulk modulus after 1.0 GPa shows values of 40(1) and 52(7) GPa in water and NaHCO3 run, respectively, confirming that stilbite becomes more compressible than that before 1.0 GPa. It is caused by the migration of cations and water molecules inside the channel, as the water molecules in the PTM start to freeze and stop to insert toward the channel at 1.0 GPa or more. In the NaHCO3 run, it is assumed that the distribution of extra-framework species inside the structure is changed by substitution of the Na+ cation. It can be expected from tendency of the relative intensity ratio of the (001) and (020) peaks which show a different from that of the water run.

Growth and Quality Characteristics of Korean Bread Wheat in Response to Elevated Temperature during their Growing Season (밀 재배기간 온도상승이 빵용 밀의 생육 및 품질 특성에 미치는 영향)

  • Chuloh Cho;Han-yong Jeong;Yurim Kim;Jinhee Park;Kyeong-Hoon Kim;Kyeong-Min Kim;Chon-Sik Kang;Jong-Min Ko;Jiyoung Shon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.67 no.4
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    • pp.234-241
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    • 2022
  • Wheat (Triticum aestivum L.) is a major staple foods and is in increasing demand in the world. The elevated temperature caused by changes in climate and environmental conditions is a major factor affecting wheat development and grain quality. The optimal temperature range for winter wheat is between 15 and 25℃, and it is necessary to study the physiological characteristic of wheat according to elevated temperatures. This study presents the effect of elevated temperature on the yield and quality of two Korean bread wheat (Baekkang and Jokyoung) in temperature gradient tunnels (TGT). Two bread wheat cultivars were grown in TGT at four different temperature conditions: T0 (control, near ambient temperature), T1 (T0+1℃), T2 (T0+2℃), (T0+2℃), T3 (T0+3℃). The period from sowing to heading stage accelerated and the number of grains per spike and grain yield reduced under T3 condition compared with those under T0 condition. Grain filling rate and grain maturity also accelerated with elevated temperature (T3). The increase in temperature led to the increase in protein contents, whereas decreased the total starch contents. These results are consistent with the decreased expression of starch synthesis genes and increased gliadin synthesis or gluten metabolism genes during the late grain filling stage. Taken together, our results suggest that the increase in temperature (T3) led to the decrease in grain yield by regulating the number of grains/spike, whereas increased the protein content by regulating the expression of starch and gliadin-related genes or gluten metabolism process genes expression. In addition, our results provide a useful physiological information on the response of wheat to heat stress.

Utilizing the Idle Railway Sites: A Proposal for the Location of Solar Power Plants Using Cluster Analysis (철도 유휴부지 활용방안: 군집분석을 활용한 태양광발전 입지 제안)

  • Eunkyung Kang;Seonuk Yang;Jiyoon Kwon;Sung-Byung Yang
    • Journal of Intelligence and Information Systems
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    • v.29 no.1
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    • pp.79-105
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    • 2023
  • Due to unprecedented extreme weather events such as global warming and climate change, many parts of the world suffer from severe pain, and economic losses are also snowballing. In order to address these problems, 'The Paris Agreement' was signed in 2016, and an intergovernmental consultative body was formed to keep the average temperature rise of the Earth below 1.5℃. Korea also declared 'Carbon Neutrality in 2050' to prevent climate catastrophe. In particular, it was found that the increase in temperature caused by greenhouse gas emissions hurts the environment and society as a whole, as well as the export-dependent economy of Korea. In addition, as the diversification of transportation types is accelerating, the change in means of choice is also increasing. As the development paradigm in the low-growth era changes to urban regeneration, interest in idle railway sites is rising due to reduced demand for routes, improvement of alignment, and relocation of urban railways. Meanwhile, it is possible to partially achieve the solar power generation goal of 'Renewable Energy 3020' by utilizing already developed but idle railway sites and take advantage of being free from environmental damage and resident acceptance issues surrounding the location; but the actual use and plan for these solar power facilities are still lacking. Therefore, in this study, using the big data provided by the Korea National Railway and the Renewable Energy Cloud Platform, we develop an algorithm to discover and analyze suitable idle sites where solar power generation facilities can be installed and identify potentially applicable areas considering conditions desired by users. By searching and deriving these idle but relevant sites, it is intended to devise a plan to save enormous costs for facilities or expansion in the early stages of development. This study uses various cluster analyses to develop an optimal algorithm that can derive solar power plant locations on idle railway sites and, as a result, suggests 202 'actively recommended areas.' These results would help decision-makers make rational decisions from the viewpoint of simultaneously considering the economy and the environment.

A Study on the Policy Proposal for the Expansion of Design Utilization in the Public Sector : Focused on the Case of the National Design Group (공공분야 디자인 활용 확대를 위한 정책제안 연구: 국민디자인단 사례를 중심으로)

  • Bang, Songhee;Kim, Taewan
    • Journal of Service Research and Studies
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    • v.13 no.3
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    • pp.160-171
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    • 2023
  • The importance of design utilization as a method for establishing policies and services in the public sector is increasing. Accordingly, Korea has introduced a public service design development method and has implemented and operated a national design group for consumer-centered policy development since 2014. This study analyzes the cases of the National Design Group to expand the use of design in the public sector and propose sustainable public service design strategies. The time range of this study is from 2014 to 2021, when the National Design Group was implemented, and the content is limited to tasks that can be found on the Gwanghwamun 1st Street website and the National Design Group casebook. This study was conducted as follows. First, we looked for implications for how to use and identify the role of design in the public policy development stage by referring to the literature on design policy and public service design, and second, based on major implications, we analyzed the task name and contents. Based on literature studies and case studies, we found implications that design can be used in various public fields, and the policy implications proposed to expand the use of sustainable design in the public sector are as follows. First, by raising awareness of service design in public policies and services, it continues to provide opportunities for the use of design to expand as a role that leads to voluntary behavioral changes of citizens beyond civic participation. Second, more active publicity is needed for the successful cases of the National Design Group, a product of the active use of public service design. Third, a more specific evaluation system should be introduced to verify the effectiveness and effectiveness of public service design. Through this, it is expected that it will greatly contribute to reducing the error in policy delivery and realizing citizen-centered public services by utilizing design for various problems facing our society.

Changes of ecological niche in Quercus serrata and Quercus aliena under climate change (갈참나무와 졸참나무의 기후변화에 따른 생태지위 변화)

  • Yoon-Seo Kim;Jae-Hoon Park;Eui-Joo Kim;Jung-Min Lee;Ji-Won Park;Yeo-Bin Park;Se-Hee Kim;Ji-Hyun Seo;Bo-Yeon Jeon;Hae-In Yu;Gyu-Ri Kim;Ju-Seon Lee;Yeon-Jun Kang;Young-Han You
    • Journal of Wetlands Research
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    • v.25 no.3
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    • pp.205-212
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    • 2023
  • This study was attempted to find out how the ecological niche and interspecies relationship of Quercus aliena and Q. serrata, which are the main constituents of potential natural vegetation along the riverside of mountains in Korea, under climate change conditions. To this end, soil moisture and soil nutrients were treated with 4 grad ients under climate change conditions with elevated CO2 and temperature, plants we re harvested at the end of the growing season, growth responses of traits were measured, ecological niche breadth and overlap were calculated, and it was compared with that of the control group(ambient condition). In addition, the relationship between the two species was analyzed by principal component analysis using trait values. As a result, the ecological niche breadth of Q. aliena was wider than that of Q. serrata under the moisture environment conditions under climate change. Under nutrient conditions, the ecological niche of the two species were similar. In addition, the ecological overlap for soil moisture of Q. aliena and Q. serrata was wider than the soil nutrient gradient under climate change. The species with traits in which the increase in ecological niche breadth due to climate change occurred more than the decrease was Q. aliena in both water and nutrient gradients. And in the responses of the population level, due to climate change, the adaptability of Q. aliena was higher than that of Q. serrata under the soil moisture condition, but the two species were similar under the nutrient condition. These results mean that the competition between the two species occurs more severely in the water environment under climate change conditions, and at that time, Q. aliena has higher adaptability than Q. serrata.

Evaluation of Road and Traffic Information Use Efficiency on Changes in LDM-based Electronic Horizon through Microscopic Simulation Model (미시적 교통 시뮬레이션을 활용한 LDM 기반 도로·교통정보 활성화 구간 변화에 따른 정보 이용 효율성 평가)

  • Kim, Hoe Kyoung;Chung, Younshik;Park, Jaehyung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.43 no.2
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    • pp.231-238
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    • 2023
  • Since there is a limit to the physically visible horizon that sensors for autonomous driving can perceive, complementary utilization of digital map data such as a Local Dynamic Map (LDM) along the probable route of an Autonomous Vehicle (AV) is proposed for safe and efficient driving. Although the amount of digital map data may be insignificant compared to the amount of information collected from the sensors of an AV, efficient management of map data is inevitable for the efficient information processing of AVs. The objective of this study is to analyze the efficiency of information use and information processing time of AV according to the expansion of the active section of LDM-based static road and traffic information. To carry out this objective, a microscopic simulator model, VISSIM and VISSIM COM, was employed, and an area of about 9 km × 13 km was selected in the Busan Metropolitan Area, which includes heterogeneous traffic flows (i.e., uninterrupted and interrupted flows) as well as various road geometries. In addition, the LDM information used in AVs refers to the real high-definition map (HDM) built on the basis of ISO 22726-1. As a result of the analysis, as the electronic horizon area increases, while short links are intensively recognized on interrupted urban roads and the sum of link lengths increases as well, the number of recognized links is relatively small on uninterrupted traffic road but the sum of link lengths is large due to a small number of long links. Therefore, this study showed that an efficient range of electronic horizon for HDM data collection, processing, and management are set as 600 m on interrupted urban roads considering the 12 links corresponding to three downstream intersections and 700 m on uninterrupted traffic road associated with the 10 km sum of link lengths, respectively.