• Title/Summary/Keyword: climate range test

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Climate Change and Individual Life History (기후변화와 개체의 생활사)

  • Lee, Who-Seung
    • Ocean and Polar Research
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    • v.34 no.3
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    • pp.275-286
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    • 2012
  • Over the last 20 years there have been more than 3000 peer-reviewed papers relating to climate change and biodiversity published, and still the numbers are increasing. However, most studies focused on the impacts of climate change at population or community levels, and the results invariably reveal that there has been, or will be, a negative effect on the structure and pattern of biodiversity. Moreover, the climate change models and statistical analyses used to test the impacts are only newly developed, and the analyses or predictions can often be misled. In this review, I ask why an individual's life history is considered in the study how climate change affects biodiversity, and what ecological factors are impacted by climate change. Using evidence from a range of species, I demonstrate that diverse life history traits, such as early growth rate, migration/foraging behaviour and lifespan, can be shifted by climate change at individual level. Particularly I discuss that the optimal decision under unknown circumstance (climate change) would be the reduction of the ecological fitness at individual level, and hence, a shift in the balance of the ecosystem could be affected without having a critical impact on any one species. To conclude, I summarize the links between climate changes, ecological decision in life history, the revised consequence at individual level, and discuss how the finely-balanced relationship affects biodiversity and population structure.

The WISE Quality Control System for Integrated Meteorological Sensor Data (WISE 복합기상센서 관측 자료 품질관리시스템)

  • Chae, Jung-Hoon;Park, Moon-Soo;Choi, Young-Jean
    • Atmosphere
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    • v.24 no.3
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    • pp.445-456
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    • 2014
  • A real-time quality control system for meteorological data (air temperature, air pressure, relative humidity, wind speed, wind direction, and precipitation) measured by an integrated meteorological sensor has been developed based on comparison of quality control procedures for meteorological data that were developed by the World Meteorological Organization and the Korea Meteorological Administration (KMA), using time series and statistical analysis of a 12-year meteorological data set observed from 2000 to 2011 at the Incheon site in Korea. The quality control system includes missing value, physical limit, step, internal consistency, persistence, and climate range tests. Flags indicating good, doubtful, erroneous, not checked, or missing values were added to the raw data after the quality control procedure. The climate range test was applied to the monthly data for air temperature and pressure, and its threshold values were modified from ${\pm}2{\sigma}$ and ${\pm}3{\sigma}$ to ${\pm}3{\sigma}$ and ${\pm}6{\sigma}$, respectively, in order to consider extreme phenomena such as heat waves and typhoons. In addition, the threshold values of the step test for air temperature, air pressure, relative humidity, and wind speed were modified to $0.7^{\circ}C$, 0.4 hPa, 5.9%, and $4.6m\;s^{-1}$, respectively, through standard deviation analysis of step difference according to their averaging period. The modified quality control system was applied to the meteorological data observed by the Weather Information Service Engine in March 2014 and exhibited improved performance compared to the KMA procedures.

An Experimental Study on In-Plate Evaporation Heat Transfer and Flow Characteristics for Automobile (자동차용 증발기 판 내의 증발 열전달 및 유동 특성에 관한 실험적 연구)

  • Kwak, Kyung-Min;Joo, Sang-Woo;Jung, Woo-Youl;Kim, Taek-Keun;Kim, Kwang-Il
    • Transactions of the Korean Society of Automotive Engineers
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    • v.15 no.2
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    • pp.95-100
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    • 2007
  • An experimental study was performed to evaluate the in-plate evaporation heat transfer and flow characteristics of a evaporator used in automobile. Two test-cores with different heat transfer area, bead-shape and bead-array were tested, A type and B type. For the heat transfer, Nusselt number for B type test-core reaches a value nearly equal to the one for A type test-core, in the whole range of equivalent Reynolds number. But, for the same mass flow rate of refrigerant, hA for B type test-core becomes higher with the increase of the mass quality of refrigerant than for A type test-core. In a flow visualization experiment, the wake zone of refrigerant circulating at u-turn position of plate is observed.

The Efficiency Characteristics of Electric Vehicle (EV) According to the Diverse Driving Modes and Test Conditions (다양한 주행모드 및 시험 조건에 따른 전기자동차 효율 특성)

  • LEE, MIN-HO;KIM, SUNG-WOO;KIM, KI-HO
    • Transactions of the Korean hydrogen and new energy society
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    • v.28 no.1
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    • pp.56-62
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    • 2017
  • Although most electricity production contributes to air pollution, the vehicle organizations and environmental agency categorizes all EVs as zero-emission vehicles because they produce no direct exhaust or emissions. Currently available EVs have a shorter range per charge than most conventional vehicles have per tank of gas. EVs manufacturers typically target a range of 160 km over on a fully charged battery. The energy efficiency and driving range of EVs varies substantially based on driving conditions and driving habits. Extreme outside temperatures tend to reduce range, because more energy must be used to heat or cool the cabin. High driving speeds reduce range because of the energy required to overcome increased drag. Compared with gradual acceleration, rapid acceleration reduces range. Additional devices significant inclines also reduces range. Based on these driving modes and climate conditions, this paper discusses the performance characteristics of EVs on energy efficiency and driving range. Test vehicles were divided by low / high-speed EVs. The difference of test vehicles are on the vehicle speed and size. Low-speed EVs is a denomination for battery EVs that are legally limited to roads with posted speed limits as high as 72 km/h depending on the particular laws, usually are built to have a top speed of 60 km/h, and have a maximum loaded weight of 1,400 kg. Each vehicle test was performed according to the driving modes and test temperature ($-25^{\circ}C{\sim}35^{\circ}C$). It has a great influence on fuel efficiency amd driving distance according to test temperature conditions.

Changes in the External Heat Environment of Building Evaporative Cooling Systems in Response to Climate Change (기후변화 대응 건축물 기화냉각시스템 적용에 따른 외부 열환경 변화 연구)

  • Yoon, Yong-Han;Kwon, Ki-Uk
    • Journal of Environmental Science International
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    • v.27 no.12
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    • pp.1261-1269
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    • 2018
  • The purpose of this study was to investigate changes in the external thermal environment, following the application of evaporative cooling systems in buildings, in response to climate change. In order to verify changes in the external thermal environment, a T-test was performed on the microclimate, Thermal Comfort Index (TCI), and building surface temperature. Differences in microclimate, following the application of the evaporative cooling system in the building, were significant in terms of temperature and relative humidity. In particular, temperature decreased by more than 7% when the evaporative cooling system was applied. According to the results of the Thermal Comfort Index analysis, the Wet-Bulb Globe Temperature (WBGT) was below the limit of outdoor activities, indicating that outdoor activities were possible. The Universal Thermal Climate Index (UTCI) values were within the very strong heat stress range when the evaporative cooling system was not applied, When the system was applied, the UTCI values were within the strong heat stress range, indicating that they were lowered by one level. The building surface temperature decreased by ~10% or more when the evaporative cooling system was applied, compared to when it was not applied. Finally, the outside surface temperature of the building decreased by ~12% or more when the system was applied, compared to when it was not applied. We conclude that the energy saving effect of the building was significant.

The Study on the Physiological Response in Wearing Sportswear in Two Different Environments

  • Kwon, Oh Kyung;Kim, Jin-A
    • Fashion & Textile Research Journal
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    • v.2 no.5
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    • pp.416-422
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    • 2000
  • In this study, to find out the physiological reaction of the human body and the sensation of comfort when people are wearing sportswear which is made of waterproof breathable fabrics under general environmental conditions (temperature : $20{\pm}1^{\circ}C$, humidity : $60{\pm}5%RH$, air current : 0.1 m/sec) and rainy environmental conditions (temperature : $20{\pm}1^{\circ}C$, humidity : $60{\pm}5%RH$, air current : 0.1 m/sec, rainfall : 250 1/hr), we made an experiment with sportswear in an artificial climate chamber and studied the thermal physiological response and subjective sensation. Mean skin temperature of the subjects was low and had a big range of fluctuation in rainy environmental conditions of two condition. Temperature started to increase at the beginning of the exercise, reached the maximum at the 2nd level of the exercise and then started to decline. Rectal temperature showed a slighter increase and bigger range of fluctuation in general conditions than in rainy conditions. Except clothing micro climate in rainy conditions, temperature and humidity and their range of fluctuation around back were higher than those around chest. Humidity was high and had wide range of fluctuation in general conditions. Heart rate was 4.4 beats/min higher in general conditions. In subjective test on rainy conditions, the feeling of discomfort increased due to the raindrops fallen on the skin. Unlike that in general conditions, cold sensation increased and humidity sensation reached to the peak after the exercise. In wearing sportswear made of shape memory breathable waterproof fabric, controlling function over a small amount of heat and water was distinctive while it turned out to be not so comfortable over a large amount of heat and water. Through this, the limitation of shape memory breathable waterproof fabric was recognised.

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Spatial Distribution of Urban Heat Island based on Local Climate Zone of Automatic Weather Station in Seoul Metropolitan Area (자동기상관측소의 국지기후대에 근거한 서울 도시 열섬의 공간 분포)

  • Hong, Je-Woo;Hong, Jinkyu;Lee, Seong-Eun;Lee, Jaewon
    • Atmosphere
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    • v.23 no.4
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    • pp.413-424
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    • 2013
  • Urban Heat Island (UHI) intensity is one of vital parameters in studying urban boundary layer meteorology as well as urban planning. Because the UHI intensity is defined as air temperature difference between urban and rural sites, an objective sites selection criterion is necessary for proper quantification of the spatial variations of the UHI intensity. This study quantified the UHI intensity and its spatial pattern, and then analyzed their connections with urban structure and metabolism in Seoul metropolitan area where many kinds of land use and land cover types coexist. In this study, screen-level temperature data in non-precipitation day conditions observed from 29 automatic weather stations (AWS) in Seoul were analyzed to delineate the characteristics of UHI. For quality control of the data, gap test, limit test, and step test based on guideline of World Meteorological Organization were conducted. After classifying all stations by their own local climatological properties, UHI intensity and diurnal temperature range (DTR) are calculated, and then their seasonal patterns are discussed. Maximum UHI intensity was $4.3^{\circ}C$ in autumn and minimum was $3.6^{\circ}C$ in spring. Maximum DTR appeared in autumn as $3.8^{\circ}C$, but minimum was $2.3^{\circ}C$ in summer. UHI intensity and DTR showed large variations with different local climate zones. Despite limited information on accuracy and exposure errors of the automatic weather stations, the observed data from AWS network represented theoretical UHI intensities with difference local climate zone in Seoul.

Spirituality of Student Nurses (일 지역 간호대학생의 영성에 관한 연구)

  • Lee Myung-Hwa
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.11 no.3
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    • pp.265-274
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    • 2004
  • Purpose: This study was to identify the level of spirituality in student nurses and to provide baseline data to develop a spirituality development education program. Method: The participants were 499 students in departments of nursing in 5 universities in Busan. The data were collected between June 7 and July 18, 2002. The instrument was used Howden's spirituality assessment scale. Collected data were analyzed with frequencies, percentages, $Means{\pm}SD$, t-test F-test, Scheffe test, and Pearson's correlation coefficient. The SPSS program was used. Results: 1) The mean score for spirituality was $101.14{\pm}8.70$ (range 26-130). 2) The mean score for perceived health state was $3.42{\pm}0.80$. 3) Spirituality according to general characteristics showed significant differences for sex, religion, practice experience, smoking, drinking, and climate of home. 4) Spirituality according to religious characteristics showed significant differences for influence of religion, necessity of religion, help from religion, subjectivity of God in life, reading religious books, participation in religion ceremonies. 5) There was a significant positive correlation between perceived health state and spirituality. Conclusion: The spirituality of the student nurses was high and differed according to sex, religion, practice experience, smoking, drinking, and climate of home, religious characteristics, spirituality, and perceived health status.

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Variation in Seed and Cone Characteristics of Loblolly Pine (Pinus taeda L.) Families in Southern Part of Korea

  • Lee, Hyunseok;Lim, Hyemin;Lee, Wiyoung;Jang, Kyunghwan;Kang, Junwon
    • Journal of Forest and Environmental Science
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    • v.34 no.1
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    • pp.82-86
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    • 2018
  • Loblolly pine (Pinus taeda L.) is widely distributed in the southern part of the United States and it has been used as a major economic species in the region due to its excellent growth and stem straightness. The tree also grows only in the southern part of Korea because it is susceptible to cold. Recently climate changes have had widespread impacts on forest trees. Thus, the use of good quality seeds is prerequisite for assessing assisted migration adaptation trial. In this study, we conducted to investigate its cone and seed characteristics of each family, which is expected to improve seeds productivity for planting valuable timber trees. A total of 14 families were selected from the experimental forest in Boseong, Jeonnam province in 1981. The seed production capacity was estimated to range from 87.2 to 129.4 among families and the average was 111.3. The number of aborted ovules was investigated in the range of 11.4 to 29.5 for the first test and 7.4 to 22.2 for the second test. The average number of empty and filled seeds was 1.4 and 79.2 per cone, respectively. Based on the results, we can conclude that there is a strong correlation between the number of fertile scale and the seed production ability.

The Precision Validation of the Precise Baseline Determination for Satellite Formation

  • Choi, Jong-Yeoun;Lee, Sang-Jeong
    • Journal of Astronomy and Space Sciences
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    • v.28 no.1
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    • pp.63-70
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    • 2011
  • The needs for satellite formation flying are gradually increasing to perform the advanced space missions in remote sensing and observation of the space or Earth. Formation flying in low Earth orbit can perform the scientific missions that cannot be realized with a single spacecraft. One of the various techniques of satellite formation flying is the determination of the precise baselines between the satellites within the formation, which has to be in company with the precision validation. In this paper, the baseline of Gravity Recovery and Climate Experiment (GRACE) A and B was determined with the real global positioning system (GPS) measurements of GRACE satellites. And baseline precision was validated with the batch and sequential processing methods using K/Ka-band ranging system (KBR) biased range measurements. Because the proposed sequential method validate the baseline precision, removing the KBR bias with the epoch difference instead of its estimation, the validating data (KBR biased range) are independent of the data validated (GPS-baseline) and this method can be applied to the real-time precision validation. The result of sequential precision validation was 1.5~3.0 mm which is similar to the batch precision validation.