• 대기
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• 제20권1호
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• pp.27-35
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• 2010

This study analyzes the climate change in Korea and its impact on the occurrence of forest fire events. The forest fire occurrences in Korea tend to concentrate around large cities. In addition, the spatial distribution of the forest fire occurrence seems to agree with local climate conditions. Though the occurrence of the forest fire shows strong interannual variation, it also exhibits a positive trend. Because the forest fire frequently occurs during early spring, we examined long term climate variability in Korea for the early spring seasons. The climate change in Korea generally has brought warmer, drier, and less precipitable conditions during the early spring. The changes of the atmospheric conditions provide favorable condition for the forest fire. The climate changes in Korea also depict distinct spatial variability according to the atmospheric variables. We compared the regional trend of the fire occurrence with the climate trends. The results show the sharpest growing in the forest fire occurrence over southwest of Korea. This study suggests that the decrease in the precipitation day might affect the sharp increasement of the forest fire occurrence in the southwest of Korea.

• 한국산림과학회지
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• 제94권4호통권161호
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• pp.277-280
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• 2005

밤나무재배지 내에 살수장치를 고정 설치하고, 이를 이용하여 일시에 약제를 살포함으로써 밤나무의 중요 종실해충인 복숭아명나방(Dichocrocis punctiferalis)의 피해를 효과적으로 방제할 목적으로 2002년에 경기도 여주군 장천면에서 연구가 수행되었다. 공시약종은 fenitrothion 50% EC 1,000배액 및 diflubenzuron 25% WP 2,500배액을 사용하였으며, 얻어진 결과는 다음과 같다. 복숭아명나방의 2세대 성충우화시기는 7월 상순부터 9월 상순까지 약 60일간이며, 우화최성기는 7월 하순부터 8월 상순의 약 10일간이었다. 살수장치(스프링클러)에 의한 수관약제살포는 관행의 지상약제살포와 비교하여 아주 효율적이었다. Diflubenzuron 25% WP 2,500배의 수관살포는 무처리의 피해율 30.4% 와 비교하여 2.3%(0.9-4.0%)로서 92%(86.7-97.0%)이상의 높은 방제효과가 있었다. 복숭아명나방에 대한 적정약제 살포시기 및 살포횟수는 7월 상순부터 8월 하순까지 10-15일 간격으로 4-5회 살포하는 것이 효과적이었다.

• 대한가정학회지
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• 제42권1호
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• pp.167-180
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• 2004

This study was carried out to investigate quality characteristics of chopped garlic stored at various temperature. Chopped garlic was stored at room temp.($25^{\circ}C$), refrigerator temp.($5^{\circ}C$) and frozen temp. ($-18^{\circ}C$) for 1, 2, 4, 8, 24, 48, 72 hours(room temp.) and 1, 3, 5, 7, 10, 15, 20, 30 days(refrigerator temp. and frozen temp.), respectively. Brown color, Hunter color value, vitamine C contents and flavor patterns by electronic noes of chopped garlic were measured. Fresh chopped garlic was used as control and garlic powder by hot air drying was used for comparisons. Brown color of chopped garlic increased with increasing storage time, and the intensity of that was reduced as following order such as chopped garlic stored at room temp., refrigerator temp. and frozen temp. Brown color of garlic powder was most dark amomg all the samples. The results of Hunter color value was consistent with then of brown color in chopped garlic, whereas those of garlic powder showed relatively low browning. Above results might be caused by the difference of measurement as only surface color was measured in Hunter color value unlike brown color. Vitamine C contents of chopped garlic decreased with increasing storage time, and in particular those stored at room temp. decreased markedly as retention of those stored at room temp. was 60％ of control after 1 day storage. Vitamine C retention of chopped garlic stored at refrigerator temp. was 78％ of control after 10 day storage and that stored at frozen temp. was 86％ of control after 30 day storage. At room temp., flavor pattern by electronic nose showed a difference between chopped garlic stored for 1hour and control, and showed occurrence of off odor after 1 day storage. Flavor pattern of garlic powder by electronic nose showed a mild flavor. Flavor patterns of chopped garlic stored at refrigerator temp. were similiar until 10 day storage, whereas those showed occurrence of volitile components after 15 day storage. Flavor patterns of chopped garlic stored at frozen temp. were similiar after 30 day storage, and especially those after 3 day storage were almost the same as control. Therefore it is desirable to store chopped garlic within 1 day at room temp. and within 10 days at refrigerator temp. And it is most desirable to store chopped garlic at frozen temp. as retention of quality characteristics was superior than other storage temp.

• 대한인간공학회지
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• 제29권4호
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• pp.405-422
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• 2010

Occupational musculoskeletal disorders currently account for the largest proportion of the occupational illnesses in Korea. In this research, status of musculoskeletal disorders among the occupational illnesses was examined through workers' compensation claims data. Types and characteristics of musculoskeletal disorders were looked at other data set as well. The data sets included epidemiological investigation data reported by Occupational Safety and Health Research Institute, and data collected from occupational disease surveillance reports and Korean occupational health-related scientific journals. Number of cases, incidence rate and insurance benefits for occupational musculoskeletal disorders in Korea are increasing every year. In addition, musculoskeletal disorders occurrence is shifted from large enterprises group to small-and-medium group, from manufacturing to service sector, and from production workers to office and professional workers. Although low back pain is still most common, its occurrence characteristics is gradually shifted from traumatic to cumulative while musculoskeletal disorders are somewhat seemingly moved from lumbar to upper limb body part. Musculoskeletal disorders were observed to be more diverse and prevalent in epidemiological investigations or surveillance data rather in workers' compensation claims data. Musculoskeletal disorders occurrence is related to demographic factors, occupational psychosocial factors, and ergonomic risk factors at workplace for which appropriate preventive measures needed to be made accordingly.

• 한국산학기술학회논문지
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• 제21권12호
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• pp.603-611
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• 2020

도로에 발생하는 포트홀은 운전자들의 안전과 만족도, 차량파손에 직접적으로 영향을 미치는 요소로 실시간에 준하는 검지와 대응이 요구된다. 순찰 빈도를 높이면 포트홀의 조속한 검지와 대응이 가능하나, 많은 인력과 비용, 시간이 소요된다. 또한 포트홀은 우천에 따라 발생특성이 달라지기 때문에 순찰의 효율성을 제고하기 위해서는 경제적 관점과 서비스 제공의 관점에서 최적빈도에 대해 고민해야 할 필요가 있다. 이에 본 연구는 장기간에 걸쳐 수집된 포트홀 발생이력과 기상정보를 활용하여 우천이 포트홀 발생에 미치는 영향과, 지속성, 강우강도의 영향에 대해 정량적 분석을 시도하였다. 그리고 이 결과를 근거로 리스크 기반의 최적화·가변화 순찰 전략을 제시하였다. 분석 결과 우천 시에는 포트홀 발생확률은 2.4배 증가하고, 비가 그친 후에도 그 영향은 3일간 지속됨을 알 수 있었다. 또한 강우강도 1mm 당 포트홀 발생확률은 0.46% 증가하며, 1mm 수준의 적은 비에도 발생특성이 민감하게 반응함도 확인하였다. 이러한 특성에 근거한 포트홀 관리 최적 빈도는 신뢰수준 95% 수준에서 우천 비영향권일 경우 3일에 1회, 영향권에서는 1일 2회 이상의 순찰이 필요하다는 결론이 도출되었다.

• 한국방재학회 논문집
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• 제2권1호
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• pp.161-167
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• 2002

전국단위로 시행되고 있는 산불위험시기가 전국 9개 지역(강원, 경기, 경남, 경북, 전남, 전북, 제주, 충남, 충북)과 차이가 있는지를 알아보기 위하여 산불발생건수와 피해면적을 가지고 순기별로 구분하여 상관분석을 실시하였다. 분석 결과 산불발생건수에서는 모든 지역에서 유의성이 있는 것으로 나타났고, 산불피해면적에서는 경남, 제주와 유의성이 없는 것으로 나타났다. 이에 전국을 대상으로 모든 지역을 설명하기에는 부족하므로 전국 9개도를 대상으로 하여 산불위험시기를 구분하기 위하여 산불발생과 피해면적을 이용하여 분산분석의 다중검정을 실시하고 순기별로 유의성 검정을 실시하였다. 그 결과 산불발생에 있어서 제주를 제외한 지역에서 1% 유의성이 있었고, 산불피해면적은 강원, 제주를 제외한 지역에서 1% 유의성을 보였다. 각 지역별로 위험시기를 구분할 수 있지만 행정적 효율성을 높이기 위하여 지역별 상관분석 결과를 이용하여 산불위험시기가 비슷한 중부권(강원, 경기, 경북, 전북, 충남, 충북), 남부권(경남, 전남), 그리고 제주권(제주)으로 분류하였다. 산불발생시기에 있어서는 중부권은 2월중순${\sim}$5월상순까지 전체의 81%가 발생한 반면 남부권은 1월하순${\sim}$4월중순까지 전체의 71%가 발생하였다. 산불피해면적에 있어서는 중부권은 2월중순${\sim}$5월상순까지 전체의 98% 가 발생한 반면 남부권은 1월하순${\sim}$4월중순까지 전체의 82%가 발생하였다.

• 천문학회보
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• 제41권1호
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• pp.45.2-45.2
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• 2016

In this study we investigate 195 spacecraft anomalies from 1998 to 2010 from Satellite News Digest (SND). We classify these data according to types of anomaly : Control, Power, Telemetry etc. We examine the association between these anomaly data and daily peak particle (electron and proton) flux data from GOES as well as their occurrence rates. To determine the association, we use two criteria that electron criterion is >10,000 pfu and proton criterion is >100 pfu. Main results from this study are as flows. First, the number of days satisfying the criteria for electron flux has a peak near a week before the anomaly day and decreases from the peak day to the anomaly day, while that for proton flux has a peak near the anomaly day. Second, we found a similar pattern for the mean daily peak particle (electron and proton) flux as a function of day before the anomaly day. Third, an examination of multiple spacecraft anomaly events, which are likely to occur by severe space weather effects, shows that anomalies mostly occur either when electron fluxes are in the declining stage, or when daily proton peak fluxes are strongly enhanced. This result is very consistent with the above statistical studies. Our results will be discussed in view of the origins of spacecraft anomaly.

• Journal of Electrical Engineering and Technology
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• 제13권2호
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• pp.591-598
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• 2018

Short term load forecasts complexly affected by socioeconomic factors and weather variables have non-linear characteristics. Thus far, researchers have improved load forecast technologies through diverse techniques such as artificial neural networks, fuzzy theories, and statistical methods in order to enhance the accuracy of load forecasts. Short term load forecast errors for special days are relatively much higher than that of weekdays. The errors are mainly caused by the irregularity of social activities and insufficient similar past data required for constructing load forecast models. In this study, the load characteristics of Lunar New Year's Day holidays well known for the highest error occurrence holiday period are analyzed to propose a load forecast technique for Lunar New Year's Day holidays. To solve the insufficient input data problem, the similarity of the load patterns of past Lunar New Year's Day holidays having similar patterns was judged by Euclid distance. Lunar New Year's Day holidays periods for 2011-2012 were forecasted by the proposed method which shows that the proposed algorithm yields better results than the comprehensive analysis method or the knowledge-based method.

• 대한간호학회지
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• 제27권1호
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• pp.96-108
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• 1997

The purpose of this study was to determine the effect of endurance training prior to occurrence of muscle atrophy on the mass, myofibrillar protein content and fiber crossectional area of atrophied hindlimb muscles of rats. Adult female Wistar rats were trained prior to occurrence of muscle atrophy induced by hindlimb suspension. Training began on the 1st day for 10min /day at 15m /min on a 0% grade, training exercise increased daily in time and intensity so that by the 4th week rats were running 60min /day, at 34m /min on a i3.5% grade. Wet weight and relative weight of soleus, plantaris and gastrocnemius muscle decreased significantly after seven days of hindlimb suspension. Wet weight and relative weight of soleus tended to increase and that of plantaris and gastrocnemius tended to decrease in the exercise group as compared to the control group. Myofibrillar protein content of soleus and gastrocnemius tended to increase and that of plantaris tended to decrease in the endurance trained group as compared to the control group. Fiber crossectional area of Type I, II fiber in soleus and plantaris muscle tended to increase in the exercise group as compared to the control group. Wet weight and relative weight of soleus. plantaris and gastrocnemius decreased significantly, myofibrillar protein content of soleus, plantaris and gastrocnemius increased in hindlimb suspended rats following endurance training as compared to the control group. There was no change in fiber type percentage and crossectional area of type I and II fiber in soleus muscle and that of type I and IIfiber in plantaris muscle decreased in the hindlimb suspended rats following endurance training as compared to the control group. Wet weight and relative weight of soleus and plantaris tended to increase, that of gastrocnemius increased significantly, myofibrillar protein content of soleus and plantaris muscle increased significantly and that of gastrocnemius tended to increase in the hindlimb suspended rats following endurance training as compared to sedentary rats following endurance training. Crossectional area of type I fiber of soleus muscle tended to increase. that of type I fiber of plantaris muscle increased significantly and that of type II fiber tended to increase in hindlimb suspended rats following endurance training as compared to sedentary rats following endurance training. The results suggest that endurance training prior to occurrence of muscle atrophy can attenuate the decrease of mass, myofibrillar protein content and fiber crossectional area induced by hindlimb suspension.

• 한국농림기상학회지
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• 제24권2호
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• pp.83-94
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• 2022

농작물 생육 과정에서 서리에 의한 동상해 피해에 능동적으로 대비하기 위해, 지난 21년간(2000~2020) 20개 지역의 서리관측 자료를 이용하여 한국 서리발생의 시공간적 분포 특성을 살폈다. 지역별 서리분포 특성은 서리일수, 첫 서리일, 끝 서리일로 표현하였다. 그리고 이러한 결과의 기후 경향은 Mann-Kendall trend test와 Sen's slope estimator를 수행하여 확인하였다. 한국에서 대부분의 서리는 태백산맥과 소백산맥 서쪽 내륙지방에서 발생한다. 상대적으로 해안지역에 가까울수록 서리 발생일이 적고 첫서리일이 느리며 끝서리일이 빠르다. 동해안지역은 서해안지역보다 서리일수가 적고 첫서리일이 느리며 끝서리일이 빠르다. 남해, 남동해, 도서지역은 거의 서리가 발생하지 않는다. 연간 시계열 추이 분석결과 한국은 기후온난화가 진행됨에도 불구하고, 서리일수가 줄어들거나 첫서리 일이 늦춰지는 경향은 나타나지 않았으며, 끝서리일은 1년에 0.5일씩 늦춰지는 것으로 나타났다.