• 농업과학연구
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• 제46권3호
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• pp.529-538
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• 2019

This study examined the changes in plant phenology of 12 woody species in Daegu University Forest, Gyeongsan-si, Gyeongsanbuk-do in 2007 and 2018. The Hobo was installed at a height of 1.2 meters to measure the microclimate such as air temperature and relative humidity to identify its effects on the changes in plant phenology. The number of trees surveyed were 42 individuals that included 12 species in 9 families, all of which are deciduous broad-leaved trees. The trends in temperature change in 2018 were similar to that in 2007, except for the temperatures in the warmest and coldest month. Compared to 2007, the average temperature of the warmest month in 2018 was $2.5^{\circ}C$ higher, and the coldest month was $3.3^{\circ}C$ lower. The lowest temperature from February to April in 2018 had the highest correlation with the blooming dates of the trees (r = 0.692) in 2018, and the highest temperature showed the lowest correlation (r = 0.392). The blooming date by species was significantly different (p < 0.05). The blooming date of 8 species (75%), including Prunus padus, was earlier by 1 to 16 days, while 4 species, such as Prunus armeniaca var. ansu, was later by 1 to 7 days in 2018 than that in 2007. However, the flowering duration did not have a significant effect on the plant phenology. The results can be used as basic data for long-term monitoring of plant phenology in the future, and follow-up studies on other environmental factors and physiological factors are needed.

• 한국농림기상학회지
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• 제14권4호
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• pp.229-235
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• 2012

본 연구는 소나무 산지의 개엽시기에 영향을 미치는 기후인자를 구명하기 위해 수행되었는데 1996년 국립산림과학원에서 조성한 정선, 충주, 제주의 소나무 산지시험림에서 조사가 이루어졌다. 휴면 중이던 동아가 부풀어 오르는 시점을 생장개시기로, 신초가 포린을 뚫고 나와 0.5mm 정도 자란 시점을 개엽시기로 정해 2004년 3월말부터 5월 중순까지 2일 간격으로 조사를했다. 개엽시기에 대한 산지 기후인자의 영향을 구명하기 위해 조림지와 산지의 기후인자를 구했으며, 각 기후인자의 생태적거리를 구해 공준상관 분석을 실시했다. 조림지별 생장개시기와 개엽시기는 제주, 충주, 정선 조림지 순으로 빨라 조림지의 평균 기온 차이에 따른 구배를 보여주었다. 종자산지의 기후인자 차이가 조림지에서의 생장개시기 및 개엽시기에 미치는 영향을 구명하기 위해 생태적거리 자료를 이용하여 공준상관 분석을 실시한 결과, 조림지와 산지 간 위도, 경도, 12~2월 최저기온, 11~2월 최고기온 그리고 생육기간 차이가 주요 인자인 것으로 추정되었다. 결론적으로 조림지보다 겨울철 기온이 낮은 곳에서 온 산지가 생장개시 및 개엽시기가 빠른 전형적인 북-남 또는 저온-고온 경사변이를 나타내 소나무 산지에 따른 지리적 유전적 변이가 존재하는 것을 확인할 수 있었다.

• Journal of Ecology and Environment
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• 제41권10호
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• pp.290-301
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• 2017

Background: Forest edges create distinctive ecological space as adjacent constituents, which distinguish between different ecosystems or land use types. These edges are made by anthropogenic or natural disturbance and affects both abiotic and biotic factors gradually. This study was carried out to assess edge effects on disturbed landscape at the pine-dominated clear-cut area in a genetic resources reserve in Uljin-gun, eastern Korea. This study aims to estimate the distance of edge influence by analyzing changes of abiotic and biotic factors along the distance from forest edge. Further, we recommend forest management strategy for sustaining healthy forest landscapes by reducing effects of deforestation. Results: Distance of edge effect based on the abiotic factors varied from 8.2 to 33.0 m. The distances were the longest in $Mg^{2+}$ content and total nitrogen, $K^+$, $Ca^{2+}$ contents, canopy openness, light intensity, air humidity, $Na^+$ content, and soil temperature followed. The result based on biotic factors varied from 6.8 to 29.5 m, coverage of tree species in the herb layer showed the longest distance and coverage of shrub plant in the herb layer, evenness, species diversity, total coverage of herb layer, and species richness followed. As the result of calculation of edge effect by synthesizing 26 factors measured in this study, the effect was shown from 11.0 m of the forest interior to 22.4 m of the open space. In the result of stand ordination, Rhododendron mucronulatum, R. schlippenbachii, and Fraxinus sieboldiana dominated arrangement of forest interior sites and Quercus mongolica, Vitis amurensis, and Rubus crataegifolius dominated spatial distribution of the open area plots. Conclusions: Forest interior habitat lies within the influence of both abiotic and biotic edge effects. Therefore, we need a forest management strategy to sustain the stability of the plant and further animal communities that depend on its stable conditions. For protecting forest interior, we recommend selective logging as a harvesting method for minimizing edge effects by anthropogenic disturbance. In fact, it was known that selective logging contributes to control light availability and wind regime, which are key factors affecting microclimate. In addition, ecological restoration applying protective planting for the remaining forest in the clear-cut area could contribute to prevent continuous disturbance in forest interior.

• 한국지리정보학회지
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• 제17권2호
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• pp.156-172
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• 2014

본 연구는 미기후 분석 프로그램인 ENVI-met 모델의 정확도를 검증하기 위해 경상남도 창원시를 대상으로 도시지역의 주요 토지이용 유형별 공간특성을 고려하여 선정된 조사구역의 현장측정 기상자료와 비교하였다. 현장측정은 주간시간대 2일, 야간시간대 1일 총 3일간이동식으로 측정하였고, ENVI-met 모델링은 현장측정과 동일한 시간대로 설정하여 수행하였다. 측정항목별 분석결과에 따르면, 주간시간대의 순복사에너지는 ENVI-met 모델링이 현장측정값보다 약 $300Wm^{-2}$ 정도 높았고, 야간시간대는 현장측정값이 $200Wm^{-2}$ 정도 더 높았다. 기온은 주간 및 야간 시간대 모두 현장 측정값이 약 $3{\sim}6^{\circ}C$ 정도 더 높은 것으로 분석되었다. 표면온도도 현장측정값이 ENVI-met 모델링보다 약 $7{\sim}13^{\circ}C$ 더 높았다. 풍속은 ENVI-met 모델링과 현장측정값 간의 차이가 매우 큰 것으로 나타났다. 회귀분석 결과에서는 기온자료의 $R^2$값이 약 0.6정도로 비교적 높게 나타난 반면에, 나머지 순복사에너지와 표면온도, 풍속은 낮은 상관성을 보였다. 이는 ENVI-met 모델링이 태양 및 지구복사에너지를 과대 또는 과소 예측하고 있으며, 모델링 및 현장측정을 위해 선정된 조사구역들을 둘러싸고 있는 인접한 주변 지역의 공간구조적, 미기후적 특성 차이에 의한 영향으로 판단된다. 따라서 향후 이에 대한 보다 면밀한 실증적 연구가 필요할 것으로 판단된다.

• 한국농림기상학회지
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• 제18권4호
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• pp.327-336
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• 2016

미얀마 중부지방에 위치한 바간(Bagan)은 지난 10년간 평균 연 강수량이 약 600 mm에 지나지 않는 건조지역으로 산불, 지역 주민의 방목 및 연료목 사용 등으로 인한 산림 훼손이 심각한 지역이다. 이에 훼손된 건조지의 복원을 위한 노력의 일환으로 조림 사업이 진행되고 있다. 본 연구의 목적은 첫째, 이 지역의 주요 조림 수종을 대상으로 수분이용효율이 양호하여 조림에 적합한 수종을 선발하고, 둘째, 조림이 해당 지역의 미세기후변화에 미치는 영향을 구명하는 것이다. 5개 주요 조림 수종(Azadirachta indica, Acacia catechu, Eucalyptus camaldulensis, Acacia leucophloea, Albizia lebbek)을 대상으로 각각 1년생 유묘와 2005년에 이식한 11년생 성목의 생장을 측정하고, 양엽에서 추출한 탄소동위원소함량(${\delta}^{13}C$, ‰)을 분석하여 수종별, 생장단계별 수분 이용효율 변화를 분석하였다. 한편 조림이 건조지의 미세기상변화에 미치는 영향을 구명하기 위해 Ngalinpoke 산지에 2005년 조림된 A. indica 숲과 전광 노출지를 대상으로 미세기상특성을 측정하였다. 2015년 2월부터 이듬해 7월까지 기온, 상대습도, 토양온도 및 토양수분 함량 등을 측정하였으며, 특히 조림에 따른 지표면의 복사열 차이를 구명하기 위해 지면으로부터 60 cm, 2 m 높이에서의 기온과 상대습도를 측정하였다. 위의 주요 조림 수종 중에 수분이용효율이 상대적으로 높은 수종은 A. indica와 A. lebbek였으며, E. camaldulensis은 수고 생장이 좋은 반면 수분이용효율이 가장 낮았다. 지상 2 m 높이에서는 기온 및 상대습도가 조림지와 노출지 사이의 차이를 보이지 않았으나, 토양온도는 두 지역간 통계적으로 유의한 차이를 보였다. 지상 60 cm 높이에서는 기온 및 상대습도가 조림지에서 노출 전광지에 비해 낮았다. 한편, 조림지에서의 토양수분함량은 전광 노출지에 비해 월별 변동폭이 컸으며 2015년 10월에는 전광 노출지에 비해 약 4배 상승하였다. 결과적으로 이 지역에서의 조림은 지표 온도를 낮추고 지표에서의 직접적인 증발을 막아줌으로써 토양 내 수분 보존에 기여하는 것으로 사료된다.

• 한국작물학회지
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• 제27권4호
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• pp.361-370
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• 1982

The effects of climatic factors on organisms lire variable and complex, and it, however, can be interpreted in terms of those on the distribution and those on the population densities. The distribution of an organism may largely be determined by the temperatures, except some temporal organisms which are depended on the air mass movements. Population density of an organism is determined by various climatic factors, such as previous winter temperature, temperature of growing season and rainfall. The start of growing season of the rice plants has been shifted to earlier since last decade in Korea. This may mean that the overall climatic condition during the growing season might be considerably different from those in past years, and such a difference in climatic conditions might have close relation with the recent status of the diseases and insect pests through direct effects on the physiology and population dynamics of the organisms, as well as through on the biotic associations of the pest organisms. The white back planthopper and brown planthopper have become the key insect pests in Korea in recent years. They are migratory and have high reproductive pontentials and more generations than average residential insects. The synchronization of the migrants and physiological condition of the rice plants seems to be the important factors in relation to the recent outbreaks of these insects; the high reproductive rate can be obtained with the growth stage of rice being 30-50 days after transplanting. The modication of the microclimate associated with high plant density and some other introduced new cultural techniques also have some relation with the outbreak. The key diseases of the rice are the blast disease, sheath blight and the bacterial leaf blight. For the rice blast, the seedling blast and leaf blast during the early growing season and the neck blast, have become more serious, the former may be related to hotbed nursery and the later may be related to the high humidity in early August, and synchronization of the heading time which has been shifted to early part from middle or late part of August. In general, for the rice diseases, the development of the new races have been the most serious which are largely resulted from the introduction of the new varieties, but it also seems to be related with the prolonged periods of the favorable condition associated with the shifted growing seasons. In general, the diseases and insect pest problems have become much more variable and complex, and control measures should be based on the thorough knowledge of the ecology of the pest organisms, that is, effects of various environmental factors on the disease cycle; spore release, spore deposition, infection, colonization and sporulation of the disease organisms, and those on the development, reproductive potentials, dispersal, age specific responses of the insects. The well organized real-time pest management systems, such as alfalfa weevil management system developed at the Purdue University in U.S., is the prime importance for the implementation of the pest management principles.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2017년도 춘계공동학술대회
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• pp.135-135
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• 2017

Greenhouse have been developed to provide the plants with good environmental conditions for cultivation crop, two major factors of which are the inside air temperature and humidity. The inside temperature are influenced by the heating systems, ventilators and for systems among others, which in turn are geverned by some type of controller. Likewise, humidity environment is the result of complex mass exchanges between the inside air and the several elements of the greenhouse and the outside boundaries. Most of the existing models are based on the energy balance method and heat balance equation for modelling the heat and mass fluxes and generating dynamic elements. However, greenhouse are classified as complex system, and need to make a sophisticated modeling. Furthermore, there is a difficulty in using classical control methods for complex process system due to the process are non linear and multi-output(MIMO) systems. In order to predict the time evolution of conditions in certain greenhouse as a function, we present here to use of recurrent neural networks(RNN) which has been used to implement the direct dynamics of the inside temperature and inside humidity of greenhouse. For the training, we used algorithm of a backpropagation Through Time (BPTT). Because the environmental parameters are shared by all time steps in the network, the gradient at each output depends not only on the calculations of the current time step, but also the previous time steps. The training data was emulated to 13 input variables during March 1 to 7, and the model was tested with database file of March 8. The RMSE of results of the temperature modeling was $0.976^{\circ}C$, and the RMSE of humidity simulation was 4.11%, which will be given to prove the performance of RNN in prediction of the greenhouse environment.

• 대한가정학회지
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• 제40권11호
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• pp.193-205
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• 2002

To evaluate farmers' workload during harvesting grapes in summer, this study investigated farmers' physiological, psychological responses, work postures and thermal environment around in the field. This field study was conducted in the Anseong County of Kyonggi Province at the end of August. Five career farmers (1 male, 4 females) volunteered as subjects. Three of them were over their sixties. During harvesting grapes in the field, physiological responses were monitored continuously. 1. Air temperature (T/sub a/), air humidity(H/sub a/), black globe temperature(T/sub g/), air velocity and WBGT around the grape field were 26.9℃, 77.7%RH, 32.8℃, 0.08㎧ and 26.3℃, respectively. Because farmers started the harvesting task in early morning, thermal environments weren't conditions to give farmers severe heat strain. 2. The percentage of the work postures was larger in order of standing, walking, and bending one's back posture. Particularly, the percentage of standing posture with raising both arms above shoulder of two farmers was up to 29% and 61% of the total work duration. 3. Rectal temperature (T/sub re/), mean skin temperature (T/sub sk/), clothing microclimate temperature (T/sub cl/) on the chest and the back, heart rate (HR) and energy expenditure (EE) were 37.2℃, 33.1℃, 32.0℃, 32.4℃, 88bpm and 1.3 Kca1/㎡/min respectively. In the point of these physiological results, we evaluated that the harvesting task was a moderate work. 4. All farmers expressed‘hard, hot, humid and slightly uncomfortable’ at the end of works for each subjective questionnaire. The grape harvesting tasks were not evaluated as a very hard work in the point of physiological work standards. But we considered 1) inappropriate work posture (standing posture with raising both arms above shoulder) and 2) farmers' age as burden factors. These findings suggest that adding adequate protective clothing/equipments for farmers may contribute to maintain their body temperature within the normal range, stabilize HR and decrease psychological strain.

• 한국환경과학회지
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• 제29권4호
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• pp.325-337
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• 2020

The purpose of this study was to analyze the soil environment of urban neighborhood parks and to use them as basic data for evaluating the ecological functions of urban parks such as groundwater regeneration, flood control, microclimate regulation, adsorption and purification. The landscape design criteria were generally evaluated as advanced, and further monitoring and studies are needed to evaluate the various ecological functions. It is also necessary to improve the phosphoric acid and nitrogen contents, which tended to be low. In addition, continuous monitoring is needed to assess the proper soil environment according to the biological species, and to evaluate the ecological functions. The results of this study can be used to evaluate the groundwater recharge of urban parks. In particular, when the land of the neighboring park is used for various purposes, the level of access of the user may be increased. Therefore, factors that may adversely affect the user's health, such as heavy metals and organic matters, should be selected and selected as management criteria. In addition, follow-up studies considering fertilization standards suitable for trees and growth of introduced vegetation, etc. are needed urgently to improve the soil environment.

• Safety and Health at Work
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• 제2권3호
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• pp.260-272
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• 2011

Objectives: The promotion of health and safety (H&S) awareness among hospital staff can be applied through various methods. The aim of this study was to assess the risk level of physical hazards in the hospital sector by combining workers' perception, experts' evaluation and objective measurements. Methods: A cross-sectional study was designed using multiple triangulation. Hospital staff (n = 447) filled in an H&S questionnaire in a general hospital in Athens and an oncology one in Thessaloniki. Experts observed and filled in a checklist on H&S in the various departments of the two hospitals. Lighting, noise and microclimate measurements were performed. Results: The staff's perception of risk was higher than that of the experts in many cases. The measured risk levels were low to medium. In cases of high-risk noise and lighting, staff and experts agreed. Staff's perception of risk was influenced by hospital's department, hospital's service, years of working experience and level of education. Therefore, these factors should be taken into account in future studies aimed at increasing the participation of hospital workers. Conclusion: This study confirmed the usefulness of staff participation in the risk assessment process, despite the tendency for staff to overestimate the risk level of physical hazards. The combination of combining staff perception, experts' evaluation and objective measures in the risk assessment process increases the efficiency of risk management in the hospital environment and the enforcement of relevant legislation.