The Evolving Policy Debate on Border Closure in Korea

Su-Jin Kang,Jihyun Moon,Heewon Kang,Heekyoung Nam,Sangwoo Tak,Sung-Il Cho 대한예방의학회 2020 Journal of Preventive Medicine and Public Health Vol.53 No.5

302 Copyright © 2020 The Korean Society for Preventive Medicine J Prev Med Public Health 2020;53:302-306 • https://doi.org/10.3961/jpmph.20.213 The Evolving Policy Debate on Border Closure in Korea SuJin Kang1, Jihyun Moon2, Heewon Kang1, Heekyoung Nam3, Sangwoo Tak1, Sung-il Cho1,3 1Institute of Health and Environment, Seoul National University, Seoul, Korea; 2Samsung Advanced Institute of Health Science and Technology, Sungkyunkwan University, Seoul, Korea; 3Department of Public Health Sciences, Graduate School of Public Health, Seoul National University, Seoul, Korea Brief Report Objectives: In this paper, we aimed to investigate the evolving debate over border closure in Korea during the coronavirus disease 2019 (COVID-19) pandemic, to address the main themes associated with border closure, and to discuss the factors that need to be considered when making such decisions. Methods: We collated and reviewed previously conducted review studies on border closures during infectious disease outbreaks to derive relevant themes and factors. Results: According to our systematic review on border closures and travel restrictions, the effects of such containment efforts are limited. We suggest considering the following factors when determining whether to impose border closure measures: (1) disease characteristics, (2) timeliness of implementation, (3) transmission delay and the basic reproduction number, (4) globalization and pandemics, and (5) social and economic costs. Conclusions: Our assessment indicates that the effects of border closures are at best temporary and limited. Alternative measures must be contemplated and implemented to suppress the spread of COVID-19 in particular and infectious diseases more broadly.

栽植密度에 따른 油菜의 生育, 靑刈收量 및 粗成分 變化

趙南棋,劉哲受,姜榮吉,宋昌吉,趙榮一 濟州大學校 亞熱帶農業硏究所 1999 亞熱帶農業硏究 Vol.16 No.-

ABSTRACT Four cultivars of rape were grown at 5 planting densities in Cheju volcanic soil to investigate the effects of planting density on major agronomic characters of forage rape. Hallayuchae flowered earliest (180 days) while Sparta latest(191 days). Days to flowering was reduced as planting density was decreased. The average plant height of Sparta was 162.2cm and that of Ramon and Youngsanyuchae was 158.4 and 138.6cm, respectively. In 10 X 10cm planting density plot, plant height was 152.5cm and it was gradually decreased as planting density was decreased. The number of branches, stem diameter, leaf length and leaf width of Ramon was greatest, while those of Hallayuchae were least. These variables were increased as planting density was decreased. Fresh forage yield (5,719kg/10a) and dry matter yield (1,229kg/10a) for lOxlOcm planting density plot, were greatest, but those were gradually decreased as planting density was decreased and those for 30 X 30cm planting density plot were 4,232kg/10a and 906kg/10a respectively. Crude protein yield and total digestable nutrient (TDN) per lOa was positively correlated with fresh forage yield and dry matter yield. Sparta produced the greatest fresh forage, and Hallayuchae produced the smallest. Sparta had the highest SPAD reading value, and Hallayuchae had the lowest. SPAD reading was reduced in proportion to increased planting density. Sparta had greater crude protein yield, and crude fat, nitrogen free extract (NFE) and TDN contents and Youngsanyuchae and Hallayuchae had lower contents while Youngsanyuchae and Hallayuchae had greater crude fiber and crude ash contents and Sparta had lower contents. Crude protein yield, and crude fat. NFE and TDN contents were decreased as planting density was decreased, while crude fiber and crude ash contents were increased as planting density was decreased.

플라이애시를 다량 사용한 콘크리트의 수화발열 특성과 압축강도 특성에 관한 실험적 연구

조규현,박무영,백민수,김우재,임남기,정상진 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2

This study is for the great quantity use of fly-ash. For the producing of high volume concrete from the use of fly-ash, the method of replacement between bonding agents and fine aggregate by fly-ash at the slt was used that the adiabatic temperature rise of concrete about the mass member which bad been produced by the method that was mentioned before, and the hydration heat of the core test pieces in concrete was measured. Also the core test pieces which were replaced with fly-ash was studied by the compressive strength's comparison between standard care test pieces and core test pieces. In the case of mass test pieces, hydration heat and the time to reach the highest temperature were decreased by an increase in replaced fly-ash's amounts of concrete. In addition, among the test pieces having the same amounts of concrete, the test pieces having more replaced amounts of fly-ash's fine aggregate showed higher hydration heat and the increased time to reach the highest temperature. Compressive strength was also increased by hydration heat's decrease according to fly-ash replacement. Replacement of fly-ash was more effective in high temperature environment.

HBR과 결합된 간헐폭기공정에 의한 도시하수의 영양소제거 특성

조남운,임봉수,손동훈 대전대학교 산업기술연구소 2000 산업기술연구소 論文集 Vol.11 No.1

In this study, the characteristics of organics and nutrient removal from municipal wastewater with various operation conditions using modified intermittent aeration combined with HBR process was investigated. This system was operated with HRT of 10hr at COD/N 1.96, COD/P 75.3, sludge recycle of 50% to 100% and 18℃ to 25℃. It has been the best operating condition to control, Oxic/Anoxic time ratio setting rate has been set 40min/20min and 100% of sludge recycle, under the conditions such as 2hr HRT at the anoxic reactor, 6hr HRT at the aeration tank. In that conditions, the removal efficiency of BOD, COD, T-N and T-P were 97.5%, 91.7%, 75% and 76.2%, respectively. The SNR(Specific Nitrification Rate) was 3.213mgNH4-N/gMv/hr and the SDNR(Specific Dinitrification Rate) was 4.5mg NO3-N/gMv/hr. T-P removal efficiency is due to biological phosphorus removal and formation of chemical precipitates by pellet. The performance of wasted sludge dewatering in this process is better than wasted activated sludge.

窒素 施用量이 Sudan grass 雜種의 主要 形質 및 飼料價에 미치는 影響

趙南棋,劉哲受 濟州大學校 亞熱帶農業硏究所 1993 亞熱帶農業硏究 Vol.10 No.-

本 硏究는 濟州道 火山灰土 土壤에서 窒素施肥量이 Suden grass 雜種의 주요 形質과 飼料價에 미치는 影響을 구명하기 위하여 10a當 窒素를 0, 10, 15, 20, 25, 30, 35㎏을 施用하여 試驗한 結果를 要約하면 다음과 같다. 1. 草長, 葉長, 葉幅, 葉數, 莖直徑, 節間長 等의 生育 形質은 窒素 施用量이 30kg까지 增施할수록 優勢하였으나, 35kg 施用區에서는 다소 減少하는 傾向이었다. 2. 10a當 生草 收量 (9628kg), 葉重 (101.8g), 莖重 (201.0g) 等은 窒素 30㎏/10a 施用區에서 많았으며, 其他 施用區에서는 施用量이 작아짐에 따라 減少되는 傾向이었다. 3. 出穗 日數는 窒素 30, 35㎏/10a 施用區에서 67日로 가장 빨랐고, 25㎏ 施用區, 15㎏, 10㎏, 無肥區 順位로 窒素 施用量이 작아짐에 따라 各 區마다 2∼3日 間隔으로 늦은 편이었다. 4. 粗指肪과 粗蛋白質은 窒素 施用量이 增加할수록 많아졌으며, 粗灰分, 可溶性無窒素物은 적어지는 傾向이었으나 粗纖維 는 뚜렷한 傾向이 없었다. 5. 10a當 生草 收量은 草長, 葉長, 葉重, 莖重, 穗重 粗蛋白質과 高度의 正의 相關을 나타내었으나 粗灰分과는 負의 相關을 나타내었다. This study was carried out to investigate the effects of nitrogen rate on major agronomic characters and feeding value of sorghum x sudangrass hybrid on volcanic ash soil of Cheju-do. Application rates of nitrogen were 0, 10, 15, 20, 25, 30 and 35㎏/10a. The results obtained are summarized as follows: 1. Plant height, leaf length, leaf width, leaf number, stem diameter, internode length increased as nitrogen rate was increased from 0 to 30㎏/10 a, but slightly decreased at 35㎏ N/10a compared to control treatment (0㎏/10a). 2. Fresh forage yield per 10a and fresh weight of leaves and stem per plant were greatest at 30㎏ N/10a and decreased with decreasing nitrogen rate. 3. Heading of sudan grass hybrid was earliest at 30, 35㎏ N/10a and delayed at intervels of 2∼3 days with decreasing nitrogen every 5㎏/10a. 4. Crude fat and crude protein significantly increased but crude ash and nitrogen free extract decreased as nitrogen rate was increased from 0 to 35㎏/10a. Crude fiber response to nitrogen rate was variable. 5. The were highly positive correlations between fresh forage yield and plant height, leaf length, fresh weight of leaves, stem and panicle, crude protein, but negative correlation between fresh forage yield and crude ash.

물이 건강에 미치는 영향 : 온천수를 중심으로

조수남 이화여자대학교 체육대학 1988 建美 Vol.- No.21

부산지역에서 산재보상을 신청한 과로사에 관한 연구

남연,오차재,박정래,이동준,조병만,이수일 大韓産業醫學會 2002 대한직업환경의학회지 Vol.14 No.1

목 적 : 부산지역의 근로복지공단에서 1991년부터 1999년까지 과로사 관련 보상심사가 이뤄진 총 219례를 대상으로 과로사의 발생양상과 그 인정여부에 영향을 밀치는 요인을 밝힘으로써 향후 과로사 관련 연구의 기초적 자료를 제공하고자 하였다. 방 법 : 부산지역의 3개 근로복지공단 지사에 소장된 과로사 심사기록을 대상으로 재해자의 인구통계학적 변수와 소속사업장과 근무환경에 대한 변수, 사망원인질환과 기존질병력, 업무상 과중부하의 성격과 분류, 직무수행성과 직무기인성 여부에 대해 조사하였다. 그리고 행정기관의 과로사 인정에 영향을 미치는 요인들을 평가하였다. 결 과 : 1. 전체 219례 중 135례(61.6 %)가 과로사로 인정을 받았으며, 96년 이후 매년 50례 이상의 보상신청이 이뤄져 왔다. 전체의 30.6 %가 50인 미만의 영세사업장 소속이었고, 직업운전사와 경비 직종이 34.7 %로 높았다. 연령층은 50대 이상이 48.8 % 였고, 하루 12시간 이상의 근무자가 29.6 % 였다. 근무형태에서는 교대근무와 심야근무 등의 불규칙 근무형태가 37.5 %였으며, 새로운업무에 배치된 지 6개월 이내에 발생한 경우가 21.5 %였다. 2. 사망원인으로는 뇌출혈 등의 뇌혈관계 질환이 전체의 49.8 %로 심장질환보다 많았고, 현행법령상의 인정범위에 속하는 경우가 85.4 %였다. 또한 선행질병력이 48.9 %에서 나타났는데, 대다수가 고혈압 등의 순환기 질환으로 확인되어 이들 병력자들의 보건관리에 중점을 둘 필요를 보였다. 3. 운전과 감시·정밀작업, 위험작업, 잦은 장기 출장 등의 위험요인에 노출된 경우가 전체의 53.9 %였고, 재해에 선행된 돌발사건이 전체의 17.8 %에서 관찰되었다. 업무상 과중부하에서 업무량증가와 업무시간연장이 전체의 64.7 % 였고, 6개월 이상의 장기적인 육체적, 정신적 과중부하가 있었던 경우가 42.5 %였다. 이 결과로 볼때 현행 법령상의 장기적인 과로에 대한 인정범위가 보다 확대되어야 할 필요를 보여준다. 4. 과중부하가 발생에 기여한 것으로 평가된 예가 전체의 76.3 %로 실제 인정율보다 높았다. 이중 충분요인으로 작용한 경우가 43.6 %, 부분요인인 경우가 10.4 %, 변경·촉진요인인 경우가 22.3 %였다. 5. 과로사 인정여부와 각 변수간의 로지스틱 회귀분석에서는 해당 업무의 근무경력이 6개월미만인 경우가 교차비 6.76(p=0.016), 사망질환이 법규상의 뇌심혈관계질환에 포함되는 경우가 교차비 3.00(p=0.034)을로 유의하게 높았다. 업무상 과중부하의 증가가 있는 경우는 교차비가 2.02로 높았으나 통계적 유의성은 다소 낮았다(p=0.081). 반면 50대 이상의 고령층과 기존 병력자의 경우는 상대적으로 불인정되는 경향을 보여 현행 행정기관의 인정기준이 과로에 민감한 대상층을 포괄하지 못하고 있음을 보여주었다. 결 론 : 부산지역에서의 과로사는 주로 50인 미만의 영세사업장 중 운전업, 경비업 등에 종사하는 40대 이상의 중·고령층 근로자에서 많았다. 재해자중 다수에서 뇌·심혈관계질환 병력이 확인되었고, 행정기관의 과로사 인정에는 법규상 인정범위의 뇌·심혈관계질환으로 사망한 경우와 재해자의 근무경력이 6개월 미만인 경우에서 인정되는 경우가 의미있게 높았다. 반면 기존 질병력이 있거나 50대 이상의 고령층의 경우 과로사로 인정되지 못하는 경우가 보다 많게 나타났다. 그러나 본 연구에서는 장기적인 과로와 과중부하를 유발하는 고위험직업에서의 과로사 빈도가 높아 현행 법규상의 과로인정기간의 범위를 넓혀야 할 것이고 직업에 대한 고려를 포함하는 인정기준의 검토와 개선이 요구된다. 그리고 과로사를 예방하기 위하여 업무시간 및 업무량의 개선과 관리가 필요할 것으로 판단된다. Onjectives : Karoshi is a word meaning death from work-overload. Work-related diseases due to continuous overwork are primarily cerebro- and cardio-vascular in nature. In korea, despite an increase in the incidence of Karoshi, it is not easy to recognise by workmen's compensation in Korea. This study intended to establish basic information concerning the incidence of Karoshi. Methods : 219 cases were collected based on workers' compensation records of three Busan Regional Centers of Labor Welfare Corporation from 1991 to 1999. The size of workplace, occupation, daily working time, type of working schedule, job tenures, characters of work-overload and duration of work-overload were investigated according of subgroups of general characterictics. Both univariate and multiple logistic regression analyses were userd to estimate the relationship between risk factors and a recognition of Karoshi. Results :1. 61.6 % of total cases were recognized as Karoshi. 30.6 % occurred in a small workplace of less than 50 workers, 34,7 % were drivers or guardss, and 48,8 % were more than 50 years old. Additionally, 29.6 % worked more than 12 hours, 37.5 % were irregular hours and shift workers and 21.5 % of the total had been on the job less than 6 months. 2. Of the causes of death, 49,8 % was cerebro-vascular diseases and it was more than cardio-vascular ones. And 80.4 % of total cases was belonged to the recognition-category of the Labour Ministry's Law. The previous desease history was found on 49.8 % of all cases. Of them, hypertension was most common as 21.9 %. 3. 53.9 % of patients were exposed to job hazards such as driving, monitoring, guarding, risky jobs and frequent long-term official trips. 64.7 % recorded a increased work-overload of job contents and working hours. Of the several types of work-overload, 42.5 % displayed long-term physical and psychotic work-overload and 22.2 % exhibited job characteristic work-overload. 4. In this study, work-overload was associated with the incidence of Karoshi in 76.3 % of cases. This rate was higher than the recognition of Workmen's compensation recorded by the Korea Labor Welfate Corporation. Of these, 43.6 % belonged to sufficient factors, 10.4 % partial factors, and 22.3 % were due to aggravating factors. 5. Logistic regression demonstrated that death due to cerebro- and cardio-vascular disease, short-tenure within 6 month was significantly associated with a recognition of Karoshi (p=0.034, OR=3.00, CI=1.09~8.30/p=0.016, OR=6.76, CI=1.43~32.07 respectively) and that an increase of work-overload was also associated, but its statistical significance was slightly lower(p=0.081, OR=2.02, CI=0.91~4.46). However, no association was found between this recognition and overtime work, hazardous job, irregular work schedule, low-income, injury-onset place, or small size of workplace. The elderly group(>50years old) and those with a previous disease history were negatively associated with recognition although the statistical associaltion was low. Conclusions : Karoshi in Busan occurred frequently in a small workplace of less than 50 workers, especially drivers or guards. Additionally, these cases worked more than 12 hours, were irregular hours and shift workers. The death due to cerebro- and cardio-vascular disease, short-tenure within 6 month was significantly associated with a recognition of Karoshi. However Karoshi in this study occurred frequently in overtime work and high risk groups of work-overload. Therefore, for prevention of Karoshi, work-overload and overtime work need improved and controled.

株當本數에 따른 油菜의 生育, 靑刈收量 및 組成分 變化

趙南棋,劉哲受,姜榮吉,宋昌吉,趙英一 濟州大學校 亞熱帶農業硏究所 1999 亞熱帶農業硏究 Vol.16 No.-

ABSTRCT Four rape cultivars were grown at 1 to 5 plants per hill to investigate the effects of the number of plants per hill on major agronomic characters of forage rape in Cheju volcanic soil. Days to flowering of Sparta was 191 days, those of Ramon and Youngsanyuchae were 189 and 188 days, respectively. And that of Hallayuchae was 180.3 days. Days to flowering decreased as number of plants per hill was increased. Sparta was tallest (153.6cm), while Hallayuchae was shortest (131.8cm). Plant height with three plants per hill( 155.3cm) was longest, while with 5 plants per hill(131.8cm) was shortest. The number of branches, stem diameter, leaf length and leaf width gradually decreased as the number of plants per hill were increased. Sparta had the greatest fresh and dry matter, total digestible nutrient (TDN) and crude protein yields, while Hallayuchae had the least. Fresh yield were greatest (7,544 kg) at the three plants per hill. Dry matter TDN, and crude protein yields were also greatest (7,544 kg) at the three plants per hill. Ramon had the greatist SPAD reading (44.7) while Youngsanyuchae had the lowest (40.7). SPAD reading were highest (44,1) in the one plant per hill plot but decreased as the number of plants per plant was increased. Sparta had greater contents of crude fiber and crude ash, but Hallayuchae and Youngsanyuchae had lower contents. The content of crude protein, crude fat, nitrogen free extract(NFE) and TDN were increased as number of plant per hill were increased. But the contents of crude fiber and crude ash were decreased as the number of plants per hill was increased.

대전 3ㆍ4 산업단지 주변의 하천수 및 지하수오염 실태조사

조남운,김태응,손동훈,임봉수 대전대학교 산업기술연구소 2000 산업기술연구소 論文集 Vol.11 No.2

The purpose of this study is to investigate the quality of surface water and groundwater near the Daejeon 3.4 industrial complex. In the case of surface water quality as considered by BOD, the water quality of the Hyun-do Bridge in Kum river was suitable to the class II (less than 3mg/L) of environmental standard for the river. The water quality of Bool-lo Dong in Kum river after joins Kab stream was class III (less than 6mg/L) and the water quality of Kab-chun Bridge was over class V as over about 8mg/L(less than 10mg/L). In the result for the groundwater at Wit-mal, the NO3-N concentration was average 14.6mg/L and maximum 23.4mg/L that was about twice more than the drinking water quality standard regulations(10mg/L). In other points, the groundwater quality was inadequate to the standard for a few items.

복합레진의 표면거칠기에 따른 투명도와 표면 색상의 차이에 관한 연구

조규정,박수정,조현구,김동준,황윤찬,오원만,황인남 大韓齒科保存學會 2006 Restorative Dentistry & Endodontics Vol.31 No.4

본 연구는 복합레진의 표면 연마에 의한 표면 거칠기가 표면 색상과 투명도에 어떤 영향을 미치는가를 알아보고자 시행하였다. Charisma (Heraeus Kulzer GmbH, Domagen, Germany)의 B1과 A3, Esthet-X (DENTSPLY Caulk, Milford, USA)의 B1과 B3 레진으로 거칠기에 따른 표면 색상을 평가하기 위한 직경 8㎜, 두께 5㎜의 시편을 제작하고, Sof-Lex finishing & polishing system(3M, ESPE Dental Products. St. Paul USA)의 C, M, F, 및 SF 디스크로 시편의 한쪽 면을 연마하였으며, 연마 전 Mylar strip으로 압축된 면을 대조군으로 하였다. 거칠기에 따른 투명도의 차이를 평가하기 위한 두께 1 ㎜의 시편을 Charisma의 A3로 제작하여, 한쪽 면을 600, 1000, 1500 및 2000번 사포로 연마하였다. 각 시편의 연마 전과 후, 연마면의 CIE L^(*)a^(*)b^(*)값과 1 ㎜ 시편의 백색과 흑색 배경판 상에서의 Y값을 spectrophotometer인 Spectrolino (GretagMacbech, Regensdorf, Switzerland)를 사용해 측정 분석하였으며, 각 시편의 연마 전과 후의 평균 표면 조드 (Ra)값을 Surface Roughness Tester SJ-301 (Mytutoyo, Tokyo, Japan)로 측정했다. L^(*)값은 재료와 색상에 상관없이 가장 거친 Sof-lex C 디스크로 연마한 군에서 가장 높은 값을 보였으며 (p < 0.05). Esthet-X B3군을 제외한 모든 군에서 Ra값이 감소함에 따라 L^(*)값도 낮아졌다. a^(*)값은 표면 거칠기에 따라 특정한 변화 양상을 보이지 않았으며, b^(*)값은 Esthet-X B1군을 제외한 모든 군에서 Sof-lex SF 디스크로 연마 시 가장 높은 값을 보였으며 (p < 0.05), Charisma B1과 Esthet-X B3군에서 Ra값과 비교적 높은 상관 관계를 보였다. Contrast ratio는 1000번과 1500번 사포로 연마한 군간을 제외한 모든 군 간에 유의한 차이를 보여으며 (p < 0.05). 표면 거칠기가 감소함에 따라 contrast ratio도 감소하였다(R2 = 0.801). The objectives of this were to evaluate the effect of surface roughness on the surface color and translucency of the composite reins. Two composite resins (Esthet-X, Dentsply, Milford, USA and Charisma, Kulzer, Domagen, Germany) were used to investigate the surface color. Charisma was used to investigate the translucency. 40 disc samples (diameter: 8 ㎜, thickness: 5 ㎜) were made by each product to measure the surface color. Ploymerized each sample's one side was treated by Sof-Lex finishing and polishing system (Group C, M, F, SF). 40 disc samples (diameter: 6 ㎜, thickness: 1 ㎜) were prepared to measure the opacity. 1 ㎜ samples were ground one side with #600, #1000, #1500 and #2000 sandpapers. CIE L^(*)a^(*)b^(*) values of each 5 ㎜ thickness samples, and XYZ values of 1 ㎜ thickness samples on the white and black background were measured with spectrophotometer (Spectrolino, GretagMacbeth, Regensdorf, Switzerland). Mean surface roughness (Ra) of all samples before and after surface treatment was measured using the Surface Roughness Tester SJ-301 (Mytutoyo, Tokyo, Japan). Regardless of type and shade of the composite resin, L^(*) values measured in group C were higher than others (p < 0.05), and L^(*) value decreased as the Ra value decreased except B3 shade of Esthet-X. But there were no significant difference in a^(*) values among groups. In control group and SF, highest b^(*) values were measured (p < 0.05), except B1 shade of Esthet-X. Contrast ratio decreased as the Ra value decreased (p < 0.05). With the above results, difference of surface roughness has influence on surface color and translucency of dental composite resins. 〔J Kor Acad Cons Dent 31(4):312-322, 2006〕