• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2008년도 추계학술대회 논문집
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• pp.519-520
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• 2008

• 한국습지학회지
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• 제21권2호
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• pp.102-113
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• 2019

조석에 따른 마산만의 수질의 차이를 파악하기 위하여 2016년 초여름(6월)과 여름(7, 8월)의 대조기 1 조석주기 내의 만조와 간조시에 6개의 조사정점에서 slack-tide sampling을 실시하였다. 조사된 모든 수질성분들의 혼합 상태는 SAL과의 사이의 상관관계를 통하여 잘 설명되고 있다. 초여름과 여름철 공통적으로 하천수 유입 물질인 TURB, DSi, NNN은 주로 보존성 혼합을, 내부증감 물질인 SS, COD, AMN, $H_2S$는 주로 비보존성 혼합을 나타내었다. 보존성 혼합은 만조와 간조의 수질 사이에 좋은 선형 관계를 나타내었고, 비보존성 혼합은 양자가 각기 다른 변동 양상을 나타내었다. 요인분석을 통하여 만조와 간조의 농도차의 시공간적 변화에 주요한 잠재변수들을 확인할 수 있었다. 초여름의 경우는 갈수기로서 외부유입 물질(allochthonous inputs)이 적으므로 농도차 변화에 주도적으로 영향을 미치는 오염원이 없이 조석, 유역으로부터 자연유입, 내부증감 등의 영향이 복합적으로 작용하여 4개의 요인(VF1~4)에 고루 분포되어 나타났다. 반면에 여름철의 경우는 하천수의 영향을 받는 ST-1에서 큰 농도차를 나타내는 지표들은 VF1 요인에 집중적으로 포함되어 나타났고, 그 밖에 내부 증감을 나타내는 지표들로 극명히 구분되어 나타났다. 실제로 항상 안정된 상태의 하구는 존재하지 않는다. Flushing time의 변화 등에 의하여 혼합양상은 항상 변할 수 있고, 여기에 내부증감으로 end-members의 조건이 변함에 따라 농도차의 발생은 불가피하다. 그러므로 하구의 수질을 조사할 때 평균적인 수질 자료를 확보하기 위한 시료 채취 방법을 항상 강구할 필요가 있다.

• 한국대기환경학회지
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• 제26권3호
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• pp.253-264
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• 2010

This study investigates the relationship between daily mortality and heat stress in Seoul, using perceived temperatures (PT) derived from a heat budget model. During the summer season, observed PT intensity showed the biggest magnitude of summer heat stress from the middle 10 days of July to the first 10 days of August. The elderly (65 and above) were found to be the most vulnerable to heat stress. The threshold PT, with a significant increase in excess mortality, was $38^{\circ}C$. No time lagged effect was observed with summer heat stress, while a high correlation was observed between anomalies in PT and relative deviation of mortality. A comparison of the heat index and the discomfort index with excess mortality revealed that the discomfort index underestimated excess mortality, whereas the heat index could not appropriately explain the increase in excess mortality correlated with the increase in excess heat. In contrast, PT was found to be the weather element that best represents excess mortality due to heat stress, and is thus expected to serve as a more reliable forecast index of human biometeorology.

• Ocean and Polar Research
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• 제25권1호
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• pp.41-52
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• 2003

Sediment trap samples were collected to find out characteristic behaviors of metals in the settling particles by using time-series sediment traps at 678m and 1678m water depths in the Bransfield Strait from December 27th, 1999 to December 26th, 2000. Total mass fluxes at the intermediate water depth (678m water depth) were high in the austral summer and low in the austral winter, whereas at the deep water depth (1678m water depth) they showed high values in both the summer and winter. Total mass fluxes were generally higher in the deep water depth than in the intermediate water depth, which indicates that a substantial amount of sediments are laterally transported by strong currents into the deep basin from the shallow water depths. Aluminium contents also showed large seasonal variations with high values in the winter and low values in the summer. On the contrary, organic carbon contents were high in the summer and low in the winter. Al contents were negatively correlated with organic carbon contents, which may be ascribed that detrital particles are diluted by organic matter produced by phytoplankton in the surface waters. Metals measured in this study exhibited three characteristic behaviors; 1) a positive correlation with Al-Ti, Fe, Mn, V, Co, and Ba, 2) a negative correlation with Al-Cd and Zn, 3) no relationship with Al-Sr, Cu, Cr, Ni. Terrestrial materials may act as a major source fer metals that are positively correlated with Al, and organic matter may be a major source for metals that are negatively correlated with Al. Enrichment factor (EF) of Fe, Mn, Ba, Vi Co, Sr, Cr, and Ni ranged from 0.5 to 1.5, whereas EF of Zn, Cu, and Cd showed much higher values than 1.

• 대한지리학회지
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• 제28권3호
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• pp.193-199
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• 1993

기후를 대기의 종합상태라 볼 때에 어느 지역의 기후요소의 변동 크기는 그 지역의 기후의 특성을 나타내는 하나의 지표가 된다. 특히 우리나라 하계 우기인 6,7,8월 동안의 강우량(1920년~1985년)의 변화경향성, 다우년과 과우년의 발생빈도, 그리고 주기 등에 대해 남한 전역의 표준강우량 및 서울, 대구, 부산, 목포, 강릉, 전주의 6개 지점의 강우를 서로 비교하였다. 그리고 남서기류의 영향이 우리나라의 하계 강우에 어떠한 영향을 미치는지 알아보기 위해 남한의 표준강우량 및 6개 지점의 강우와 인도 하계 몬순(monson) 강우와의 상관관계를 조사하였다. 남한 전역의 표준강우량의 평균은 611.6mm이고 표준편차는 165.5mm로서 평균의 21%이다. 6개 지점별 강수량의 평균은 지역에 따라 차이가 심하고 다우년과 과우년의 발생횟수 역시 지역에 따라 차이가 심하다. 변화경향성을 조사한 통계량 r는 남한 전역의 표준강우량의 경우 0.07이며 각 지점별 강우의 경우에도 비슷한 통계량 크기를 나타냈으며 이러한 값들은 통계적으로 유의하지 않다. 즉, 변화경향성은 없다. 우리나라 하계강우의 주기는 2.4~2.5년, 3.1~3.6년 그리고 7.3년으로 나타났다. 우리나라 하계강우와 인도 하계몬순 강우와의 상관은 대구와 전주같은 내륙지방에서는 크게 나타나고, 그 외 해안에 인접한 지역에서는 잘 나타나지 않고 있다.

• The Korean Journal of Physiology
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• 제3권1호
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• pp.29-32
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• 1969

Skinfold thickness measurement and total body fat calculation were made in summer (July) and winter (December or January) On 70 medical students (age: 20 yr),8 national team basketball players (age: 20 yr), and 9 middle-age men. Skinfold thickness measurements were made on 4 sites, namely, back, arm, waist and abdomen. The mean skinfold thickness (mm) of the 4 sites was substituted into the following formulae. For adult of 20 years old: % Fat=0.911x+8.1, and for middle-aged men % Fat=1.199x+1.41. In young medical students and ball players body weight decreased, mean skinfold thickness increased in winter season. As a result total body fat .(% body weight) increased in winter In middle-aged men both body weight and mean skinfold thickness increased in winter and resulted in an increase in the total body fat. The detailed data are as follows: 1. In medical students summer: winter values were: body weight, 59.7 :58.9 kg; mean skinfold thickness, 7.85 : 8.12 mm; and total body fat, 15.0 : 15.5% body weight (P<.30). 2. In national team basketball players summer: winter values were: body weight, 73.5 : 69.1 kg; mean skinfold thickness, 7.2 : 7.5 mm; total body fat, 11.6 : 12.1% (P:NS). 3. In middle-aged men summer vs winter values were: body weight, 61.5 : 63.0 kg; mean skinfold thickness, 10.3 : 11.8 mm; total body fat, 17.2 : 18.0% (P:NS). 4. Skinfold thickness on back showed no seasonal variation and on abdomen the thickness increased in winter. 5. It was concluded that the predominant factor in increasing total body fat in winter is the decrease in body exercise in the winter time.

• 대기
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• 제22권4호
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• pp.465-472
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• 2012

Using various observed data, we examined the evolution of tropical Pacific sea surface temperature (SST) during 2011-2012, with focusing on the development of 2012 El Ni$\tilde{n}$o. It is observed that a La Ni$\tilde{n}$a event during 2011 was followed by a moderate El Ni$\tilde{n}$o during 2012 summer. The 2012 summer El Ni$\tilde{n}$o initiated near the west coast of South America on February 2012, and continued to expand westward till August. Given this evolutionary pattern, the 2012 summer El Ni$\tilde{n}$o can be categorized as 'Eastern Pacific (EP) El Ni$\tilde{n}$o' because Ni$\tilde{n}$o-3 index is greater than Ni$\tilde{n}$o-4 index, and it may be the first well-defined EP El Ni$\tilde{n}$o since 2001. On February 2012, this event was initiated mainly by the local air-sea interaction, and at the same time the ocean heat content was accumulated over the tropical western Pacific due to the easterly wind anomaly over the tropical western Pacific. Then, the accumulated heat content slowly propagates to the tropical eastern Pacific, which attributes to maintain El Ni$\tilde{n}$o state during 2012 summer. After August, the positive SST anomaly over the equatorial eastern Pacific decays possibly due to the exhausted heat content and the weakening of air-sea interaction, but the weak positive SST anomaly over the central Pacific remains till now (2012 November).

• 한국환경과학회지
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• 제24권6호
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• pp.819-826
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• 2015

This study measured temperatures and albedos of urban surfaces for different colors and materials during summer, and calculated the energy budget over different urban surfaces to find out the thermal performance affecting the heat built-up. The study selected six surface colors and 13 materials common in urban landscape. Their surface temperatures (Ts) and albedos were measured at a given time interval in the daytime from June to August. Average Ts over summer season for asphalt-colored brick was $4.0^{\circ}C$ higher than that for light red-colored one and $9.7^{\circ}C$ higher than that for white-colored one. The Ts for artificial surface materials of asphalt paving, brown brick wall, and green concrete wall was $6.0^{\circ}C$ higher than that for natural and semi-natural ones of grass, grassy block, and planted concrete wall. There was the greatest difference of $16.3^{\circ}C$ at midafternoon in the Ts between asphalt paving and planted concrete wall. Average albedo over summer season of surface materials ranged from 0.08 for asphalt paving to 0.67 for white concrete wall. This difference in the albedo was associated with a maximum of $15.7^{\circ}C$ difference at midafternoon in the Ts. Increasing the albedo by 0.1 (from 0.22 to 0.32) reduced the Ts by about $1.3^{\circ}C$. Average storage heat at midday by natural and semi-natural surfaces of grass and grassy block was about 10% lower than that by artificial ones of asphalt, light-red brick, and concrete. Reflected radiation, which ultimately contributes to heating the urban atmosphere, was 3.7 times greater for light-red brick and concrete surfaces than for asphalt surface. Thus, surfaces with in-between tone and color are more effective than dark- or white-colored ones, and natural or semi-natural surfaces are much greater than artificial ones in improving the urban thermal environment. This study provides new information on correlation between Ts and air temperature, relationship between albedo and Ts, and the energy budget.

• 전기학회논문지
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• 제66권12호
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• pp.1873-1878
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• 2017

Both the introduction of the Renewable Energy Portfolio Standard (RPS) system into the electric energy market in 2012 and a decrease in the cost of constructing photovoltaic (PV) power plants have been increasing the number of MW PV plants in South Korea. Jeju Island is located at the center of three nations, South Korea, China and Japan, and its provincial government declared in 2012 that the island will be a clean region where greenhouse gases are not emitted by 2030. The Jeju provincial government is now doing its best to install PV plants and wind farms to realize a carbon-free island. In this study we investigated contribution of MW PV plants to the power of the electric grid during summer peak times on Jeju Island. Mt. Halla the highest mountain in South Korea, is located at the center of Jeju Island, and we divided the island into four regions and carried out analyses of a total of 24 PV plants. The average contribution of the PV plants in the respective region to electric power of Jeju Island during summer peak times was investigated and compared with those of the other regions. The best average contribution during the 12.5% maximum load period was obtained from the PV plants in the western region, and the value was 33% during 2015 and 2016.

• 한국산업보건학회지
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• 제22권2호
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• pp.128-133
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• 2012

People are exposed to air pollution from a range of indoor and outdoor sources. Concentration of nitrogen dioxide $(NO_2)$, which is hazardous to health, can be significant in both types of environment. This paper reports on the measurement and analysis of indoor and outdoor $NO_2$ concentrations and their comparison with measured personal exposure in house and workplace indoors with 28 office workers during winter and summer seasons. Time activity patterns were used to determine the effects of these factors on personal exposure. The residential indoor and office indoor times were $12.29{\pm}1.58,$ $7.86{\pm}1.97$ hours in winter and $11.04{\pm}2.18,$ $8.26{\pm}2.04$ hours in summer, respectively. Measured residential indoor, outdoor and office indoor, personal exposure $NO_2$ concentrations were $23.10{\pm}8.46$ ppb, $23.97{\pm}6.86$ ppb, $21.91{\pm}11.50$ ppb, $22.08{\pm}8.64$ ppb in winter, and $19.94{\pm}6.04$ ppb, $21.21{\pm}6.84{\pm}$ ppb, $22.55{\pm}9.54$ ppb, $27.45{\pm}8.96$ ppb in summer, respectively. Contributions of residential and office indoor $NO_2$ concentration on personal exposure were estimated by 57.98%, 35.62% in winter and 37.38%, 28.97% in summer, respectively.