• Title/Summary/Keyword: climatic condition

Search Result 214, Processing Time 0.034 seconds

Thermal and subjective responses by sun hats for farmer in a hot climatic chamber (서열 환경에서 농작업 모자 착용에 따른 체온 조절 및 주관적 반응)

  • 김명주;최정화
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.28 no.5
    • /
    • pp.713-722
    • /
    • 2004
  • This study examined the effects of two kinds of functional sun hats through a head-manikin test and a climatic chamber trial for farm workers in summer. Experiment was composed of four conditions. The first condition was the condition without any hat (Control). The second was the condition with a sun hat on the market (Hat A). The third was the condition with a functional sun hat made of reflective fabric (Hat B). The last was the condition with a functional sun hat having a ventilating structure as well as reflective fabric (Hat C). For the subjects in the climatic chamber trials, 12 healthy males volunteered. Air temperature, relative humidity and globe temperature in the chamber was maintained at $33{\pm}0.5^{\circ}C,\;65{\pm}5%RH\;and\;39{\pm}1^{\circ}C\;(WBGT\;33^{\circ}C)$. Subjects did a simulated red pepper-work (50-min work and 10-min rest, twice repetition) for 120 min. As the result of head-manikin test, the surface temperature on middle of back-neck was the lowest in Hat B of four conditions and the surface temperature on top of head was the lowest in Hat C. As the result of climatic chamber trials, there were apparent differences between with (Hat A, Hat B, Hat C) and without a sun hat (Control). In rectal temperature ($T_{re}$), mean skin temperature ($\={T}_{sk}$), heart rate (HR), total sweat rate (TSR), The physiological heat strain was less in the condition with hats than in the condition without a sun hat. As the increasing rate in Tre, Hat B is the most effective hat for alleviation heat strain. As the subjective responses, Hat B was the most effective hat for thermal comfort even though the difference was not significant. Hat C was less effective than Hat B and the reason might be the increase of weight due to inserting the ventilating structure.

Assessing the variability of climate indices and the role of climate variables in Chungcheong provinces of South Korea

  • Adelodun, Bashir;Cho, Hyungon;Odey, Golden;Adeola, Khalid Adeyemi;Choi, Kyung Sook
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2022.05a
    • /
    • pp.154-154
    • /
    • 2022
  • The frequency of natural disasters, including floods and drought events, driven by climate change has increased in recent times. Investigating the climate regimes and the roles of climate variables are indispensable to forestall future climate change-related disasters. This study compares the variability of two popular and widely used climate indices i.e., the United Nations Environment Programme (UNEP) aridity index and the Modified De-Martonne (MDM) index to assess the trend of climate change in the Chungcheong provinces of South Korea. The trend of annual and monthly climate indices was conducted using a non-parametric Mann-Kendall test and Kolmogorov-Smirnov normality test with daily climate data of 48 years (1978-2020) from 10 synoptic stations. The findings indicate that UNEP and MDM indices had a wet climate regime for the annual trend, with the UNEP index indicating a relatively humid trend of 60% humid, 20% semi-arid, and 10% sub-humid for the 48-years study period. However, the MDM index showed a high frequency of a severe wet climatic condition followed by the semi-arid condition. The months of July and August had the highest occurring frequency of the wet climatic condition (90%) for both UNEP and MDM indices. Comparing the two provinces, Chungnam showed a relatively wetter climatic condition using the UNEP index, while the MDM index indicated no significant regional difference in climate regime between the two provinces. The Kolmogorov-Smirnov normality test showed that all the 10 stations are normally distributed for monthly climate conditions at a 5% significant level in the two provinces except five stations for UNEP index and four stations for MDM index in the month of January.

  • PDF

Pollution Cycle Method with NSDD Contaminant (불용성 오손물을 이용한 오손주기시험법)

  • Lee, Won-Yeong;Choi, Nam-Ho;Park, Gang-Sik;Han, Sang-Ok
    • Proceedings of the KIEE Conference
    • /
    • 2001.07c
    • /
    • pp.1481-1483
    • /
    • 2001
  • There is a wide climatic difference between Korea and foreign countries. Thus, the pollution cycle method, based on the climatic condition of Korea, is needed to evaluate the electrical properties of outdoor insulators. We make a analysis on the cycle methods of foreign countries, climatic conditions of Korea and failure data to make the cycle method. From the result, we can design a good pollution cycle method to evaluate the electrical properties of outdoor insulators.

  • PDF

Development of a Monitoring Technique of Dryness and Wetness in Watershed using Climatic Water Budget (기후학적 물수지에 의한 유역의 건조 및 습윤 상황 감시 기법 개발)

  • Shin, Sha-Chul;Hwang, Man-Ha;Ko, Ick-Hwan
    • Journal of Korea Water Resources Association
    • /
    • v.41 no.2
    • /
    • pp.173-184
    • /
    • 2008
  • Climatic water balance has been applied to obtain quantity of various hydrologic components. Hydrologic information is estimated by comparison between rainfall and evapotranspiration under complex terrain condition. Water deficit is defined as that subtraction of actual supply from climatic demand. The water deficit will occur, when monthly evapotranspiration exceed monthly rainfall. Contrary water surplus is defined as that surplus water after meeting the demand by plants. The water surplus will be occurred when monthly rainfall exceeds monthly evapotranspiration. Finally, the discrete moisture indices were calculated and mapped for the whole watershed to estimate dryness and wetness status using the climatic water balance approach. The result of this study can properly interpret the real drought and non drought. Based upon the results, it can be concluded that the climatic water balance model is useful to monitor water conditions for the watershed.

Effect of Climatic Conditions on Pollination Behavior of Honeybees (Apis mellifera L.) in the Greenhouse Cultivation of Watermelon (Citrullus lanatus L.)

  • Lee, Kyeong Yong;Lim, Jeonghyeon;Yoon, Hyung Joo;Ko, Hyeon-Jin
    • Journal of Apiculture
    • /
    • v.33 no.4
    • /
    • pp.239-250
    • /
    • 2018
  • We investigated the pollination activity of honeybees (Apis mellifera L.) in terms of different climatic conditions in the greenhouse cultivation of watermelons (Citrullus lanatus L.) during winter. The aim of the study was to search a climatic condition which effectively can be use honeybees as pollinators during the flowering season of watermelons in winter or early spring. The average climatic conditions inside the greenhouse during the bee activity time (BAT)-between 10:00 and 16:00 in mid-Februarywere a temperature of $30.4^{\circ}C$, relative humidity of 53.7%, illuminance level of 22,728.4lx, and UV level of $0.233mW/cm^2$. Bee traffic and foraging activity were at their greatest at 10:00 and tended to decrease with time. Male watermelon flowers typically dehisced between 10:00 and 12:00. Climatic conditions were significantly correlated with bee activities, including bee traffic and foraging activity. Bee activities were positively correlated with temperature, illuminance level, and UV level but negatively correlated with relative humidity. Temperature had the greatest effect on honeybee behavior. Among the foraging honeybees, the number of high-flying bees that did not pollinate flowers showed a strong positive correlation with temperature, and the number of bees landing on the flowers showed a positive correlation with the UV level. The temperature range inside greenhouses at which the pollination activities of honeybees can be maintained efficiently during winter watermelon pollination was found to be $21{\sim}25^{\circ}C$.

Spatio-Temporal Projection of Invasion Using Machine Learning Algorithm-MaxEnt

  • Singye Lhamo;Ugyen Thinley;Ugyen Dorji
    • Journal of Forest and Environmental Science
    • /
    • v.39 no.2
    • /
    • pp.105-117
    • /
    • 2023
  • Climate change and invasive alien plant species (IAPs) are having a significant impact on mountain ecosystems. The combination of climate change and socio-economic development is exacerbating the invasion of IAPs, which are a major threat to biodiversity loss and ecosystem functioning. Species distribution modelling has become an important tool in predicting the invasion or suitability probability under climate change based on occurrence data and environmental variables. MaxEnt modelling was applied to predict the current suitable distribution of most noxious weed A. adenophora (Spreng) R. King and H. Robinson and analysed the changes in distribution with the use of current (year 2000) environmental variables and future (year 2050) climatic scenarios consisting of 3 representative concentration pathways (RCP 2.6, RCP 4.5 and RCP 8.5) in Bhutan. Species occurrence data was collected from the region of interest along the road side using GPS handset. The model performance of both current and future climatic scenario was moderate in performance with mean temperature of wettest quarter being the most important variable that contributed in model fit. The study shows that current climatic condition favours the A. adenophora for its invasion and RCP 2.6 climatic scenario would promote aggression of invasion as compared to RCP 4.5 and RCP 8.5 climatic scenarios. This can lead to characterization of the species as preferring moderate change in climatic conditions to be invasive, while extreme conditions can inhibit its invasiveness. This study can serve as reference point for the conservation and management strategies in control of this species and further research.

Experimental Study on Developing of Double Facade System dealing with the various climatic Conditions (다양한 기후조건에 대응하는 이중외피시스템 개발에 관한 실험적 연구)

  • Lee, Keon-ho;Kim, Hyeon-soo;Jang, Dae-hee;Moon, Soo-young
    • KIEAE Journal
    • /
    • v.5 no.2
    • /
    • pp.19-26
    • /
    • 2005
  • Every site has a different given geometrical and climatic condition, which influenced not only the lifestyle of the humanbeings but also the regional architecture. For example, on a cold region, the reduction of the energy loss is necessary, like an igloo, which has a littlest energy loss at hemisphere. Or on a warm region, the house must be protected thermally from the overheating at the sunshining. like a huge shading. An architectural interpretation in the (extreme) moderate climate, like Korea, has always tried to satisfy the both opposite demands simultaneously. A facade, which divides out- and inside, has an ideal position to lead the regulated regional climatic conditions into the room. The Double Facade System(DFS) is well known as an innovative solution in the european countries, like Germany. It provides an reasonable alternative, which can achieve these goals at the same time. A Double Facade System provides an effective sunshade, which means a cooling energy reduction at the warm season. In addition, it enables a natural ventilation at the cold season with the preheating at the system as well as spring and autumn. An ordinary Single Facade System with a inside or outside sun blind provides a solution just for a specified season, like a summer or winter. But the Double Facade System can deal with the various climatic conditions in the moderate climate.

A Study on the Appropriate Tunnel Bracket using in Korea Peninsula (국내 기후와 환경에 적합한 터널브래킷 선정에 관한 연구)

  • Jang, Kwang-Hun;Seo, Ki-Bum
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.63 no.7
    • /
    • pp.1008-1012
    • /
    • 2014
  • Tunnel bracket is used in railway tunnel area in order to maintain insulation. Insulator performance evaluation test is proceeded refer to IEC 61109 but it is impossible to reflect all the field condition where insulator installed. Korea has clear four season in climatic condition and peninsula with lots of mountain in geomorphology condition. Tunnel bracket material which used in korea are butyl rubber, polymer and silicone. Most of them were installed without any internal climatic and geomorphology condition. According to the KORAIL operation data most of the insulator break down occurs in tunnel. So interval of inspection period is shorter then any other insulator and lots of maintenance cost incurs. Most major railway advanced country such as germany and japan maintain tunnel bracket with their own experience. For example visual inspection carried out with in one or two years and detailed inspection carried out between three to five years. This paper analyzed materials and shapes of tunnel bracket to in order to find optimized one in korea peninsula. Proposed bracket were tested under regulation and experience field data. Finally it was installed at the field and evaluated until now.

Study on the International Climatic Testing Standard for Passenger Car (철도차량의 국제 기후환경 시험규격의 수행방안 연구)

  • Yoon, Young-Kwan;Cho, Young-Min;Choi, Jin-Sik;Jung, Woo-Sung;Kwon, Soon-Bark;Park, Duck-Shin
    • Proceedings of the KSR Conference
    • /
    • 2011.10a
    • /
    • pp.1327-1334
    • /
    • 2011
  • subway has became citizen's feet which can transport over 24 million people since the era of high oil price started. Because the request of passengers for more comfortable thermal comfort is drastically increasing, the importance of comfortable environment in the passenger car is more stressed. This paper suggests an indicator whether railroad car is fitted with suitable cooling and heating equipment by applying the international climatic testing method, UIC 553, 553-1. Specified ambient temperature, humidity, solar irradiation condition, as well as extreme outside condition, can be achieved by using an environmental chamber. The change temperature and humidity in the passenger space can be monitored to judge if the passenger room is nicely air-conditioned.

  • PDF

Correlation Analysis between Climate and Contamination Degree through Multiple Regression Analysis (다중회귀 분석을 통한 기후 및 오손도 간의 상관관계 분석)

  • Kim, Do-Young;Lee, Won-Young;Shim, Kyu-Il;Han, Sang-Ok;Park, Kang-Sik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2003.05e
    • /
    • pp.49-52
    • /
    • 2003
  • The performance of insulators under contaminated conditions is the underlying and the most factor that determines insulation design for outdoor applications, Among the contamination factors, The sea salt is the most dangerous factor, and the salt factor have closed relation with climatic conditions, such as wind, temperature, humidity and so on, Effect of these factors to insulation system is different of each other, and need to show the correlation by multiple regression analysis techniques. In this paper, predicted and analyzed equivalent salt deposit density (ESDD) by change climatic condition through multiple regression analysis.

  • PDF