• Asian Journal of Atmospheric Environment
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• 제3권1호
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• pp.52-58
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• 2009

Airborne particulates were collected in three different size fractions (>7 ${\mu}m$; 2.1-7 ${\mu}m$; < 2.1 ${\mu}m$) by using Andersen low-volume air samplers at three sites in Tieling city, Liaoning Province, a typical local city in northeast China, in every season during the period from July 2003 to May 2004. Nine polycyclic aromatic hydrocarbons (PAHs) and seven nitropolycyclic aromatic hydrocarbons (NPAHs) in the airborne particulates were determined by HPLC with fluorescence and chemiluminescence detection, respectively. The mean total concentrations of the nine PAHs and seven NPAHs were highest at The mixed residential and light industrial site, and lowest at the residential site near the suburbs. At all sites, more than 70% of the total PAHs and more than 60% of the total NPAHs were found in the finest particulate (< 2.1 ${\mu}m$) fraction. Both cluster analysis and several diagnostic ratios showed that the major contributors of PAHs and NPAHs in airborne particulates were coal combustion systems such as domestic stoves and coal boilers in all seasons in Tieling city.

• 환경위생공학
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• 제9권1호
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• pp.53-61
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• 1994

Sungnam city, as a major satellite town, is located in the southeast of Seoul. Atmospheric conditions are so stable that air pollutants from various emissions are tend to resist change because Sungnam city is located in the Namhansansung valley. The industrial distribution of Sungnam city are composed of various manufactories such as foods, fibers, chemicals, machinery and electronics etc. The heavy metal concentrations and size distribution are the most important parameters influencing among the way in which respirable suspended particulate matter interact with the human respiratory system. Respirable suspended particulate matter was collected on glass fiber filters from April 1993 to February 1994 according to particle size using Anderson sampler during 10 days per month at Sungnam city. 6 heavy metals, Fe, Zn, Pb Mn, Cu and Cd, were analyzed by particle size with atomic absorption spectrophotometry . The results could be summarized as follows: 1. The annual arithmetic mean concentration of total suspended particulate was 116.3$\mu $g/m$^{3}$ m', seasonal variation was the highest in spring season(196.5$\mu $g/m$^{3}$) and the lowest in Summer Season(72.9$\mu $g/m$^{3}$). 2. The ratio of airborne particulate concentrations respirable to nonrepairable( Res/Non- Res) of annual arithmetic mean value was 5.8'1, seasonal variation was highest in the spring season(6.3 : 1) and lowest in the summer season(4.6 : 1). 3. During the spring season the shape of the size distribution was trimodal which showed peaks at 3 size groups, which were below of 0.43$\mu $m, 3.3∼4.7$\mu $m and above of 11.0$\mu $g/m$^{3}$ respectively. 4. Respirable suspended particulate matter concentrations of Zn, Pb Cu and Cd were the highest in below of 0.43$\mu $m as follows; 0.517$\mu $g/m$^{3}$, 0.411 $\mu $g/m$^{3}$, 0.062$\mu $g/m$^{3}$ and 0.0310$\mu $g/m$^{3}$ , respectively, Fe and Mn were the highest in the particle size range of 4.7 ∼ 7.0$\mu $m as follows; 2.504$\mu $g/m$^{3}$ and 0.095$\mu $g/m$^{3}$, respectively. 5. The Pt Cd, Zn, Cu, Fe and Mn concentrations of annual arithmetic mean value respirable to non- respirable( Res/Non- Res ) were 33.65, 19.27, 17.74, 10.54, 3.20 and 5.20, respectively.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2001년도 춘계학술대회 발표논문집
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• pp.62-65
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• 2001

1997년과 1998년 4월 1일자의 M&A제한규정이었던 증권거래법 제200조의 철폐와 적대적 M&A의 전면허용 그리고 외국자본의 투자제한의 간소화 등 규제완화조치와, 향후 외국인에 대해서 100%까지 주식을 매입할 수 있는 적대적 M&A가 허용될 것으로 보여 우리나라에서도 M&A활동이 보다 본격화 될 것으로 전망되고 있다. 우리나라에서는 1980년대부터 M&A에 대한 관심과 연구가 시작되면서 지금까지 기업합병ㆍ인수의 동기와 효과에 대해서 많은 연구가 이루어져 왔다. 지금까지의 연구내용은 대부분 기업의 M&A동기는 시너지효과를 얻기 위함이며, 또한 공시정보가 합병공시일 전후동안에 주가수익율에 반영되어 합병 당사기업의 주주의 부에 영향을 미치는지의 주가변화 유무에 국한된 것이었다. 또한 1985년부터 1991년 초 사이에 이루어졌던 연구는 당시 국내 M&A 환경이 매우 열악하고 극히 제한된 비정상적인 자본시장 상황 하에서 이루어진 사례에 의한 연구이었기 때문에 연구결과의 문제점과 한계성이 있었고, 실효성 측면에서도 다소 미흡하였다고 할 수 있다. 우리나라 M&A의 성장발전과정을 크게 2단계로 분류한다면, 제1단계는 1975년부터 시작하여 1990년까지로써 이 기간동안의 M&A환경은 그 여건조성과 성숙준비단계였으며, 제2단계인 1990년 초부터 비로소 선진국형 시장경제원리에 근거한 보다 경쟁적이고 자율적인 M&A 시장구조가 형성되면서 활성화 단계로 진입하였다고 볼 수 있을 것이다. 본 연구의 주된 목적은 1990년부터 1996년 사이에 이루어진 상장기업의 M&A 사례를 표본으로 하여 한국에서의 기업합병과 기업인수(주식취득)가 기업가치에 미치는 영향을 구명하는데 있다. 이를 위하여 먼저, M&A 당사기업의 합병성과 발생과 차이 유무를 주가수익율을 측정하여 실증분석하고 다음으로 M&A에 따른 시너지의 잠재적 원천이 어디에 있는지 재무성과분석을 통해서 이를 실증하는데 목적이 있다.PA-designated retailers ("sellers") must accept end-of-life items returned to them by the consumers. At the local level, Taipei City implements a pay-as-you-throw program, whereby citizens pay waste collection and treatment fees through the purchase of special trash bags approved by the Taipei City Government. However. recyclables that are separated by citizens are collected free-of-charge by the City. Taichung City and Kaohsiung City, on the other hand, enforce mandatory sorting schemes, whereby citizens face penalties if they don't separate recyclables from the trash before pick-up. These programs have resulted in a significant reduction in municipal waste. Per capita waste collected per day has dropped from 1.143 kg in 1997 to 0.978 kg in 2000. Targeting a 10% recycling rate for municipal waste in 2001. EPA plans to research and develop new recycling techniques, expand the scope of producer responsibilities, and strengthen existing mu

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권2호
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• pp.110-117
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• 2000

Relationship between monoclonal antibody (MAb) productivity and growth rate, and effects of high cell density on MAb production rate increased with increasing specifis growth rate in both suspended and immobilized continuous cultures indicate a positively growth-associated relationship between MAb productivity and growth rate. moreover, the specific production rate was higher in the immobilized cell culture than that in suspended one at all dilution rates. In order to clarify these phenomana, MAb mPNA experession and cell cycle distribution were investigated in bacth cultures with immobilized cells and suspended cells. RT-PCR was used for observation of MAb mRNA expression and a two-color bromodeoxyuridine (BrdU)/propidium iodide (PI) flow cytometry method for determination of cell cycle distribution. The results revealed that MAb nRNA expression until dead phase, which was longer than in suspended cell. The cell cycle distribution patterns were observed almost the same for both immobilized and suspended cells. Such results may imply that a high cell density state has positive influence on the mRNA expression and on growth-associated Mab productivity of T0405 cells.

• 대한토목학회논문집
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• 제34권3호
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• pp.1033-1041
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• 2014

우리나라는 세계적으로 유례없이 도시화가 급속하게 이루어졌으며 그 결과, 국토 면적의 10%인 수도권에 인구의 50%가 밀집하여 국토 개발의 불균형 및 열섬현상을 비롯한 각종 도시 문제가 수도권을 중심으로 발생하고 있다. 이에 수도권의 과잉 밀집을 해소하고 국토의 균형개발을 위해 2012년 7월 세종특별자치시가 출범하였으며, 세종시는 2000년대 후반부터 실질적인 개발이 진행되어 급격한 도시화를 겪고 있는 곳으로 급격한 개발에 따른 도시 문제를 수반할 것으로 예상된다. 도시화로 인한 지표면 특성의 변화는 도시열섬의 주요인이며 도시열섬현상은 결과적으로 도시지역의 기후변화 및 자연환경에 영향을 끼칠 수 있다. 본 논문은 급속한 도시화를 겪고 있는 세종시를 대상으로 도시화의 정도와 도시열섬효과를 파악하였고 도시화와 지표면온도와의 상관관계를 분석하였다. 이를 위하여 LANDSAT 영상을 사용하였으며, 2001년부터 2013년까지의 LANDSAT의 $0.63{\mu}m-1.75{\mu}m$에 해당하는 적색, 근적외선, 중적외선 영역 영상으로 NDVI, NDBI, UI를 산출하였고, $10.4{\mu}m-12.5{\mu}m$에 해당하는 열적외선 영역대의 영상을 통하여 세종시의 지표온도를 추정하였다. 산출된 각 지수와 지표면 온도를 바탕으로 세종시의 NDVI의 변화, UI의 변화를 파악하였고, TVI를 통해 도시열섬을 분석하였다. TVI를 통해 새로 건설된 행정중심복합도시 지역 일대를 중심으로 도시열섬현상이 두드러지게 증가한 것을 확인할 수 있었고 각 지수와 지표온도와의 상관관계 분석 결과 NDVI가 높을수록 온도는 낮아지는 음의 상관 관계를, NDBI와 UI는 증가할수록 온도가 높아지는 양의 상관관계를 갖는 것으로 나타났으며 이 중에서도 UI는 지표면 온도와 가장 강한 양의 상관관계를 보였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2007년 가을학술발표회
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• pp.78-89
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• 2007

Two design examples of deep foundations for high-rise buildings on soft ground are introduced in this paper. The first one is a 54-story building in Ho-Chi-Minh city, Vietnam, which was designed to be founded on $2.8m{\times}1.0m$ barrette foundations with approximately 60m to 75m depth. Based on a number of design guides and existing load test data from the construction sites in Ho-Chi-Minh city, the capacity of a barrette foundation in sand or clay layered ground was calculated to be 17.2MN to 27.8MN depending on the installing depth. The second one is a 40-story building in Baku city, Azerbaijan, which was designed to be supported by 2.0m diameter bored pile foundations with approximately 23m depth. As analytical or empirical guides for the local ground conditions were very limited, the design procedure from the SNiP Code, one of Russian specifications, was adopted and used to calculate the pile capacity. The capacity of bored pile foundation in highly weathered soil was expected to be 14.8MN to 15.5MN depending on the boring depth.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.975-976
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• 2006

The present paper is a parameter study of zinc flake production using a Simoloyer CM01 horizontal high energy rotary ball mill. The manufactured flakes have a dimension in thickness (t) < $1{\mu}m$ and diameters (d) 5-100 ${\mu}m$, consequently a ratio d/t up to 200. The flake geometry is mainly controlled by the variation of process parameters such as rotary speed of the rotor, ratio of powder/ball charge, load ratio of the system, process temperature, operating model and the quantity of process control agent (PCA). The Zn flakes were characterized by SEM, tap densitometry, laser diffraction and water coverage measurement.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.233-233
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• 2006

• 한국언어정보학회:학술대회논문집
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• 한국언어정보학회 1995년도 Language, Information and Computation = Proceedings of the 10th Pacific Asia Conference, Hong Kong
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• pp.133-138
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• 1995

• 한국환경과학회지
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• 제24권5호
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• pp.679-687
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• 2015

Atmospheric aerosol particles were investigated at GNTECH university in Jinju city. Samples were collected using the Nanosampler period from January to December 2014. The Nanosampler is a 6 stage cascade impactor(1 stage : > $10{\mu}m$, 2 stage : $2.5{\sim}10{\mu}m$, 3 stage : $1.0{\sim}2.5{\mu}m$, 4 stage : $0.5{\sim}10{\mu}m$, 5 stage : $0.1{\sim}0.5{\mu}m$, back-up : < $0.1{\mu}m$) with the stages having 50% cut-off ranging from 0.1 to $10{\mu}m$ in aerodynamic diameter. The mass size distribution of Atmospheric aerosol particles was unimodal with peak at $1.0{\sim}2.5{\mu}m$ or $0.5{\sim}1.0{\mu}m$. The annual average concentrations of TSP, $PM_{10}$, $PM_{2.5}$, $PM_1$, $PM_{0.5}$ and $PM_{0.1}$ were $44.0{\mu}g/m^3$, $40.3{\mu}g/m^3$, $31.4{\mu}g/m^3$, $18.0{\mu}g/m^3$, $8.0{\mu}g/m^3$, $3.0{\mu}g/m^3$, respectively. On average $PM_{10}$, $PM_{2.5}$, $PM_1$, $PM_{0.5}$ and $PM_{0.1}$ make up 0.91, 0.70, 0.41, 0.19 and 0.07 of TSP, respectively. The annual average of $PM_{2.5}/PM_{10}$ ratio was 0.77.