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Effect of an Offshore Fish Culture System on the Benthic Polychaete Community (외해가두리 양식이 저서다모류군집에 미치는 영향)

  • Jung, Rae-Hong;Yoon, Sang-Pil;Kim, Youn-Jung;Lee, Won-Chan;Hong, Sok Jin;Park, Sung-Eun;Oh, Hyung Taik
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.18 no.4
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    • pp.195-205
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    • 2013
  • Excessive input of organic matters from fish cage farming has been considered as one of the major factors disturbing benthic ecosystem, especially in semi-enclosed coastal waters. Recently offshore aquaculture in the vicinity of Jeju-do has been introduced to minimize that kind of negative impact. This study was conducted to investigate the ecological impacts of offshore aquaculture on the macrobenthic polychaete communities. A total of ten sampling works were carried out for 28 months, spanning from 10 days after starting giving feed to 3 months after stopping giving feed. During the study period, mean current velocity was quite strong with the range of 50 cm/s to 70 cm/s. TOC of surface sediment was constantly low. Significant changes in polychaete community were detected just three months after starting giving feed, which were the increase of the number of species and density at all stations. Up to 18 months after the start of farming, the amount of feed provided played an important role in the fluctuation of the number of species and density, especially at 0 m and 10 m stations. After reducing the amount of feed provided, dominance of some opportunistic species within 10 m distance from fish cages still lasted to the end of aquaculture. However, opportunistic species disappeared 3 months after the end of farming, which indicated the sign of recovery from the disturbance. From these results, the amount of food input and the period of cultivation were critical factors disturbing polychaete community and ensuing changes in this offshore and oligotrophic waters as well. In addition, study on the changes of polychaete community structure before and after fish farming showed more detailed changes in benthic ecological state than geochemical approach did.

Dietary Risk Assessment for Polycyclic Aromatic Hydrocarbons in Foods (식품중 Polycyclic Aromatic Hydrocarbons의 위해성평가)

  • 이효민;윤은경;박경아;김윤희;정소영;권기성;김명철;송인상;이철호
    • Journal of Food Hygiene and Safety
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    • v.19 no.1
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    • pp.1-8
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    • 2004
  • This study was executed to determine the cumulative dietary risk of PAHs exposed by food ingestion. Food samples including barbecued beef, barbecued pork, grilled chicken, ham, bacon and vegetable oil which were collected from food markets. These samples were saponified, extracted and cleaned up to purify PAHs, and then the purified sample solutions were analyzed by HPLC-FL. Generally, the levels of total PAHs in barbecued beef (0.2 ppb), bacon (0.3 ppb), barbecued pork (0.7 ppb), ham (0.8 ppb), and vegetable oil (1.2 ppb) were low, whereas the level of total PAHs in grilled chicken (9.3 ppb) was significantly high. For the exposure assessment of PAHs due to food ingestion, PAHs levels converted into TEQ$_{BaP}$, the average body weight for 20-73 age group and consumed levels of food proposed from report on the National Health and Nutrition Survey were used. The estimated lifetime average daily intake of dietary PAHs was 4.32${\times}$10$^{-4}$ $\mu\textrm{g}$-TEQ$_{BaP}$kg/day as the mean value. The dietary risk adjusted to cancer potency of benzo(a)pyrene as 7.3 (mg/kg/day)$^{-1}$ was 3.44${\times}$10$^{-6}$ based on current data.ata.

Change of asparagine content in soybean sprouts by variety, root growth, and cultivation period (콩나물의 품종, 뿌리발생 및 재배일수에 따른 asparagine 함량 변이)

  • Jeong, Yeon-Shin;Park, Hee Joon;Dhakal, Krishna Hari;Lee, Jeong-Dong;Lee, In-Jung;Hwang, Young-Hyun
    • Current Research on Agriculture and Life Sciences
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    • v.26
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    • pp.63-69
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    • 2008
  • The varietal difference, effect of root amounts and cultivation duration on the asparagine content of soybean sprouts, which is known to have the excellent detoxifying effect of ethanol, were investigated for developed varieties and indigenous sprout lines to establish cultivation methods of increasing the asparagine content and to develop soybean varieties having high asparagine content. Some of the research results obtained are summarized as follows; 1. Range and mean of asparagine content of 174 germplasm were 0.38~1.67% and 0.99%, respectively, on fresh weight basis. 2. Developed sprout-soybean varieties showed somewhat higher asparagine content of 1.29% than that of indigenous sprout lines of 0.96% on fresh weight basis. 3. No significant difference in asparagine content among the seed size groups was recognized though the highest asparagine content, 1.02% on fresh weight basis was observed in the seed size of 8.1~10.0g/100 seeds. 4. Among the seed coat color groups, soybean of brown seed coat color showed the highest asparagine content (1.15%) on fresh weight basis. No difference was observed among other groups of seed coat color. 5. Range of asparagine content of 174 varieties was 4.08~6.24% on dry weight basis. Soybean varieties that showed high asparagine content were Dawonkong, Sobacknamulkong, Sowonkong, and Somyungkong, with the contents of 6.24%, 6.21%, 5.95%, and 5.85%, respectively. 6. Amount of roots which have the highest asparagine content out of sprout parts was greatly increased up to 10 days of sprout cultivation. 7. Highly significant difference in asparagne content of sprout was recognized between those grown for five and ten days, with the asparagine content of 0.68% and 1.21%, respectively, on fresh weight basis. 8. Asparagine content of hypocotyle part was also highly proportional to days to cultivation; it increased from 2.91% at 2 days of cultivation to 15.68% on fresh weight basis at 14 days of cultivation.

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A Study on the Correspondence and the Autonomy between the Act on the Guarantee of Rights of and Support for Persons with Developmental Disabilities and the Similar Ordinances of the Local Governments (발달장애인 권리보장 및 지원에 관한 법률과 지방자치단체 유사조례 간의 연계성과 자치성에 관한 연구)

  • Jeon, Jihye;Lee, Sehee
    • 한국사회정책
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    • v.25 no.2
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    • pp.367-402
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    • 2018
  • This study analyzed the relationship between the act on the guarantee of rights of and support for persons with developmental disabilities(Act for PWDD) and the similar ordinance of the local governments based on this law and focused on the correspondence(the rate of reflection) and the autonomy(differentiation). As of October 2017, 63 local government regulations and Act for PWDD were analyzed in this study. The results of the analysis are as follows: First, the rate of reflection in the ordinance of Act for PWDD was different according to the clause. In the aspect of emphasizing welfare support, the agreement between local ordinance and rate was high. While the Act for PWDD emphasized the rights of persons with developmental disabilities, there was little information about their right in the ordinance of local governments. This is evidence that current ordinance is based on the protective point of view for people with developmental disabilities. In the future, policy measures will be needed to ensure that respect for decision-making by persons with developmental disabilities and rights guarantees are included in the bylaws. Second, there is a provision that the rate of ordinance reflection is 0%, which may be guaranteed by other laws in the area, so it does not mean the absence of related system in the region, but there is possibility of institutional blind spot. In the future, consideration should be given to the complementarity of other legal systems in the area with developmental disabilities, so that persons with developmental disabilities should not be placed in institutional blind spots. Third, the autonomy(differentiation) of local ordinance was examined from the contents aspect and the administrative aspect to help practical implementation. The differentiation between the ordinances vary. Emphasizing the responsibilities of the head of the organization, emphasizing the fact-finding survey, setting up the welfare committee, or adding local needs were included to the ordinance. Local governments considering the enactment of ordinances in the future should refer to these cases and establish enactable local ordinances that take advantage of the characteristics of local autonomy.

Analysis of Microclimate Impact According to Development Scenarios of Vacant Land in Downtown Seoul - A Comparison of Wind Speed and Air Temperature - (서울 도심 공지의 개발 시나리오에 따른 미기후 영향 분석 - 풍속 및 기온 비교 -)

  • Baek, Jiwon;Park, Chan;Park, Somin;Choi, Jaeyeon;Song, Wonkyong;Kang, Dain;Kim, Suryeon
    • Journal of Environmental Impact Assessment
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    • v.30 no.2
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    • pp.105-116
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    • 2021
  • In the city of high population density crowded with buildings, Urban Heat Island (UHI) is intensified, and the city is vulnerable to thermal comfort. The maintenance of vacant land in downtown is treated as a factor that undermines the residential environment, spoils the urban landscape, and decreases the economic vitality of the whole region. Therefore, this study compared the effects on microclimate in the surrounding area according to the development scenarios targeting the vacant land in Songhyeon-dong, Jongno-gu, Seoul. The status quo, green oriented, building oriented and green-building mediation scenarios were established and ENVI-met was used to compare and analyze the impact of changes in wind speed, air temperature and mean radiant temperature (MRT) within 1 km of the target and the target site. The result of inside and 1 km radius the targeted area showed that the seasonal average temperature decreased and the wind speed increased when the green oriented scenario was compared with the current state one. It was expected that the temperature lowered to -0.73 ℃ or increased to 1.5 ℃ in summer, and the wind speed was affected up to 210 meters depending on the scenario. And it was revealed that green area inside the site generally affects inside area, but the layout and size of the buildings affect either internal and external area. This study is expected to help as a decision-making support tool for developing Songhyeon-dong area and to be used to reflect the part related to microclimate on the future environmental effects evaluation system.

Effects of Climatic Factors on the Nationwide Distribution of Wild Aculeata (Insecta: Hymenoptera) (전국 야생 벌목 분포에 대한 기후요인 영향 연구)

  • Yu, Dong-Su;Kwon, Oh-Chang;Shin, Man-Seok;Kim, Jung-Kyu;Lee, Sang-Hun
    • Korean Journal of Environment and Ecology
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    • v.36 no.3
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    • pp.303-317
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    • 2022
  • Climate change caused by increased greenhouse gas emissions can alter the natural ecosystem, including the pollination ecosystem and agricultural ecology, which are ecological interactions between potted insects and plants. Many studies have reported that populations of wild bees, including bees and wasps (BW), which are the key pollinators, have gradually declined due to climate change, leading to adverse impacts on overall biodiversity, ultimately with agribusinesses and the life cycle of flowering plants. Therefore, we could infer that the rising temperature in Korean Peninsula (South Korea) due to global warming has led to climate change and influenced the wild bee's ecosystem. In this study, we surveyed the distributional pattern of BW (Superfamily: Apoidea, Vespoidea, and Chrysidoidea) at 51 sites from 2017 (37 sites) to 2018 (14 sites) to examine the effects of climatic factors on the nationwide distribution of BW in South Korea. Previous literature has confirmed that their distribution according to forest climate zones is significantly correlated with mean and accumulative temperatures. Based on the result, we predicted the effects of future climate changes on the BW distribution that appeared throughout South Korea and the species that appeared in specific climate zones using Shared Socioeconomic Pathways (SSPs). The distributions of wild BW predicted by the SSP scenarios 2-4.5 and 5-8.5 according to the BIOMOD species distribution model revealed that common and endemic species will shift northward from the current habitat distribution by 2050 and 2100, respectively. Our study implies that climate change and its detrimental effect on the ecosystem is ongoing as the BW distribution in South Korea can change, causing the change in the ecosystem in the Korean Peninsula. Therefore, immediate efforts to mitigate greenhouse gas emissions are warranted. We hope the findings of this study can inspire further research on the effects of climate change on pollination services and serve as the reference for making agricultural policy and BW conservation strategy

Simulation Analysis of Urban Heat Island Mitigation of Green Area Types in Apartment Complexes (유형별 녹지 시뮬레이션을 통한 아파트 단지 내 도시열섬현상 저감효과 분석)

  • Ji, Eun-Ju;Kim, Da-Been;Kim, Yu-Gyeong;Lee, Jung-A
    • Journal of the Korean Institute of Landscape Architecture
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    • v.51 no.3
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    • pp.153-165
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    • 2023
  • The purpose of this study is to propose effective scenarios for green areas in apartment complexes that can improve the connection between green spaces considering wind flow, thermal comfort, and mitigation of the urban heat island effect. The study site was an apartment complex in Godeok-dong, Gangdong-gu, Seoul, Korea. The site selection was based on comparing temperatures and discomfort index data collected from June to August 2020. Initially, the thermal and wind environment of the current site was analyzed. Based on the findings, three scenarios were proposed, taking into account both green patches and corridor elements: Scenario 1 (green patch), Scenario 2 (green corridor), and Scenario 3 (green patch & corridor). Subsequently, each scenario's wind speed, wind flow, and thermal comfort were analyzed using ENVI-met to compare their effectiveness in mitigating the urban heat island effect. The study results demonstrated that green patches contributed to increased wind speed and improved wind flow, leading to a reduction of 31..20% in the predicted mean vote (PMV) and 68.59% in the predicted percentage of dissatisfied (PET). On the other hand, green corridors facilitated the connection of wind paths and further increased wind speed compared to green patches. They proved to be more effective than green patches in mitigating the urban heat island, resulting in a reduction of 92.47% in PMV and 90.14% in PET. The combination of green patches and green corridors demonstrated the greatest increase in wind speed and strong connectivity within the apartment complex, resulting in a reduction of 95.75% in PMV and 95.35% in PET. However, patches in narrow areas were found to be more effective in improving thermal comfort than green corridors. Therefore, to effectively mitigate the urban heat island effect, enhancing green areas by incorporating green corridors in conjunction with green patches is recommended. This study can serve as fundamental data for planning green areas to mitigate future urban heat island effects in apartment complexes. Additionally, it can be considered a method to improve urban resilience in response to the challenges posed by the urban heat island effect.

A study of analytical method for Benzo[a]pyrene in edible oils (식용유지 중 벤조피렌 분석법 비교 연구)

  • Min-Jeong Kim;jun-Young Park;Min-Ju Kim;Eun-Young Jo;Mi-Young Park;Nan-Sook Han;Sook-Nam Hwang
    • Analytical Science and Technology
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    • v.36 no.6
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    • pp.291-299
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    • 2023
  • The benzo[a]pyrene in edible oils is extracted using methods such as Liquid-liquid, soxhlet and ultrasound-assisted extraction. However these extraction methods have significant drawbacks, such as long extraction time and large amount of solvent usage. To overcome these drawbacks, this study attempted to improve the current complex benzo[a]pyrene analysis method by applying the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method that can be analyzed in a simple and short time. The QuEChERS method applied in this study includes extraction of benzo[a]pyrene into n-hexane saturated acetonitrile and n-hexane. After extraction and distribution using magnesium sulfate and sodium chloride, benzo[a]pyrene is analyzed by liquid chromatography with fluorescence detector (LC/FLR). As a result of method validation of the new method, the limit of detection (LOD) and quantification (LOQ) were 0.02 ㎍/kg and 0.05 ㎍/kg, respectively. The calibration curves were constructed using five levels (0.1~10 ㎍/kg) and coefficient (R2) was above 0.99. Mean recovery ratio was ranged from 74.5 to 79.3 % with a relative standard deviation (RSD) between 0.52 to 1.58 %. The accuracy and precision were 72.6~79.4 % and 0.14~7.20 %, respectively. All results satisfied the criteria ranges requested in the Food Safety Evaluation Department guidelines (2016) and AOAC official method of analysis (2023). Therefore, the analysis method presented in this study was a relatively simple pretreatment method compared to the existing analysis method, which reduced the analysis time and solvent use to 92 % and 96 %, respectively.

The study of heavy rain warning in Gangwon State using threshold rainfall (침수유발 강우량을 이용한 강원특별자치도 호우특보 기준에 관한 연구)

  • Lee, Hyeonjia;Kang, Donghob;Lee, Iksangc;Kim, Byungsikd
    • Journal of Korea Water Resources Association
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    • v.56 no.11
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    • pp.751-764
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    • 2023
  • Gangwon State is centered on the Taebaek Mountains with very different climate characteristics depending on the region, and localized heavy rainfall is a frequent occurrence. Heavy rain disasters have a short duration and high spatial and temporal variability, causing many casualties and property damage. In the last 10 years (2012~2021), the number of heavy rain disasters in Gangwon State was 28, with an average cost of 45.6 billion won. To reduce heavy rain disasters, it is necessary to establish a disaster management plan at the local level. In particular, the current criteria for heavy rain warnings are uniform and do not consider local characteristics. Therefore, this study aims to propose a heavy rainfall warning criteria that considers the threshold rainfall for the advisory areas located in Gangwon State. As a result of analyzing the representative value of threshold rainfall by advisory area, the Mean value was similar to the criteria for issuing a heavy rain warning, and it was selected as the criteria for a heavy rain warning in this study. The rainfall events of Typhoon Mitag in 2019, Typhoons Maysak and Haishen in 2020, and Typhoon Khanun in 2023 were applied as rainfall events to review the criteria for heavy rainfall warnings, as a result of Hit Rate accuracy verification, this study reflects the actual warning well with 72% in Gangneung Plain and 98% in Wonju. The criteria for heavy rain warnings in this study are the same as the crisis warning stages (Attention, Caution, Alert, and Danger), which are considered to be possible for preemptive rain disaster response. The results of this study are expected to complement the uniform decision-making system for responding to heavy rain disasters in the future and can be used as a basis for heavy rain warnings that consider disaster risk by region.

Development and evaluation of Pre-Parenthood Education Program for high school students based on Home Economics subject (고등학생을 위한 가정교과 기반 예비부모교육 프로그램 개발 및 평가)

  • Noh, Heui-Yeon;Cho, Jae Soon;Chae, Jung Hyun
    • Journal of Korean Home Economics Education Association
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    • v.29 no.4
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    • pp.161-193
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    • 2017
  • The purpose of this study was to develop and evaluate pre-parenthood education program(PPEP) based on Home Economics(HE) subject for high school students. The development and evaluation of PPEP based on HE subject in this study followed ADDIE model except implementation through 4 processes such as analysis, design, development, and evaluation. First, program development directions were set in three aspects such as 'general development', 'contents', and 'teaching and learning methods'. Themes of the program are 11 in total such as '1. Parenting, what is being a parent', '2. Choosing your spouse, happy marital relationship, the best gift to your children', '3. Pregnancy and birth, a moving meeting with a new life', '4. Taking care of a new born infant for 24 hours', '5. Taking care of infants, relationship with my lovely baby, attachment', '6. Taking care of young children, my child from another planet', '7. Parents and children in healthy family', '8. Parent-child relationship, wise parents to make effective interaction with their children', '9. Parents safety manager at home,', '10. Practice to take care of infants', and '11. Practice of community nurturing support service development'. In particular, learning activities of the program have major characteristics such as 1) utilization of cases including practice problems related to parenting, 2) community exchange activities utilizing learned knowledge and techniques, 3) actual life project activities utilizing learning contents related with parenting, 4) activities inducing positive changes in current life of high school students, and 5) practice activities for the necessities of life such as food, clothing and shelter supporting development of children. Second, the program was developed according to the design. Teaching-learning plans and materials for 17 classes were developed according to 11 themes. The developed plans include class flow and teacher's reference. It starts with receiving a class-related message from a virtual child at the introduction stage and ended with replying to the message by summarizing contents of the class and making a promise as a parent-to-be. That is the basic frame of class flow. Learning materials included various plans and reports necessary for learning activities and they are prepared in details so that they can be play the role of textbooks in regular curriculum. Third, evaluation of developed program was executed by a 5 point Likert scale survey on 13 HE experts on two aspects of program development process and program development results. In the evaluation of development process, mean value was 4.61 and index of content validity was 97.4%. For development results, mean value was 4.37 and index of content validity was 86.9%. These values showed that validity in the development process and results in this study was highly secured and confirmed that PPEP based on HE was appropriate and valid to enhance parent qualifications of high school learners.