효율적인 구매발주 시스템을 위한 P2P기반 자동처리 모듈

추철민,이길홍 서울産業大學校 2005 논문집 Vol.54 No.3

시대의 흐름과 함께 업무에 필요한 다양한 요구사항이 발생하고 있으며 업무환경 또한 빠르게 변화하고 있다. 기존 업무 외에 새로운 업무가 추가되기도 하고 기존의 업무는 다른 업무로 대치되거나 없어지는 경우도 있다. 업무의 빠른 변화와 함께 기업에서는 빠른 변화에 대처하기 위하여 기존 시스템을 유지보수하거나 재사용을 통해 새로운 프로세스를 기존 시스템에 적용하고자 많은 자원과 시간을 투자하고 있으며 관련된 많은 연구가 진행 중에 있다. 본 논문에서는 기존의 구매발주시스템과 업무환경의 변화로 새롭게 추가도니 프로세서를 연계하여 효율적인 구매발주 시스템의 개선과 업무의 효율성을 향상하도록 하였다. 이러한 결과로 기존 구매발주시스템에서 해결하지 못한 반복오더 문제, 구매발주 후 확인처리 문제, 업체별 자료공유 문제를 개선하여 P2P기반 자동처리 모듈 설계 및 구현을 통해 처리 가능 하도록 하였다.

우리나라 청정지역에서 측정한 PM_(2.5) 입자의 특성

이종훈,김용표,문길주,김희강,정용승,이종범 江原大學校 附設 環境硏究所 1998 環境硏究 Vol.15 No.-

Atmospheric fine particles (PM_(2.5)) were collected at the background sites, Kangwha, Taean, and Kosan and characterized to understand their behaviors at the sites. Daily samples of PM_(2.5) mass were measured and ionic species, carbonaceous species, and gaseous species were analyzed. Four-daγ backward trajectory analysis was also carried out. The mean concentrations of anthropogenic species were highest at Kangwha among three sites, while contributions from sea salts were highest at Taean during the measurement period due to higher wind speed at Taean. Major chemical components in fine particles were sulfates organic carbon, nitrate, and ammonium. Most of the non-sea-salt (nss) sulfates in PM_(2.5) might be present as ammonium sulfates at these sites. Most air parcels arriving at Kangwha and Taean were from northern China. Therefore, both sites were thought to be affected by the same air parcel. At Kosan, during the measurement period, air parcels were from either northern China or southern China. The nss sulfate concentration in the air parcels from southern China was higher, while the nss calcium nitrate, and ammonium concentrations were higher when the air parcels were from northern China.

고산에서 측정한 PM_(2.5) 이온 농도 특성 : 1998~2002년 측정자료 Measurement Data between 1998 and 2002

김나경,김용표,강창회,문길주 한국대기환경학회 2003 한국대기환경학회지 Vol.19 No.3

The aerosol ionic composition of PM2.5 measured at Gosan, Jeju Island, Korea, for years between March 1998 and February 2002 are presented and discussed. The annual mean concentration of non-sea-salt sulfate(nss-SO₄²^(-)) and ammonium(NH₄+) ions are high (0.094 μeq/m³ and 0.085μeq/m³, respectively). Also, nss-SO₄²^(-) and NH₄^(+) show high correlation(0.892). The concentrations of most ions are high in springtime. As the result of factor analysis, Gosan area mainly affected by sea-salt, anthropogenic species, and crustal species.

스모그 챔버에서 수분 반응에 의한 대기 에어로졸의 생성 및 성장

김민철,배귀남,문길주,박주연 한국대기환경학회 2004 한국대기환경학회지 Vol.20 No.2

Aerosol formation and growth by water vapor reactions were investigated in a 2.5-㎥ indoor smog chamber filled with the unfiltered ambient air. The relative humidity of test ambient air was elevated at 59~64% or 84~88% by adding water vapor. The aerosol number size distribution and the concentrations of O₃, NO, NO₂, and SO₂ were measured during the experiments. The O₃, and NO₂ gases were well reacted with the water vapor at high relative humidity of 84~88%, and the reaction rates of these gases seemed to be decreased at low relative humidity of 59~64%. The formation and condensational growth phenomena of ambient aerosols by water vapor reactions were observed in a Teflon bag, depending strongly on the initial particle size distribution. The water vapor reactions might be affected by the contents of oxidants produced by photochemical reactions under sunlight.

우리 나라 배경농도지역의 1996~1997년 미세입자상 탄소성분 측정 결과

김용표,이종훈,문길주,김희강,이종범 江原大學校 附設 環境硏究所 1999 環境硏究 Vol.16 No.-

The concentrations of organic carbon (OC) and elemental carbon (EC) in fine aerosols were determined from the samples collected at the two background sites of Kosan in Cheju Island and Kangwha. Samplings were carried out during the spring and winter of 1996 and the fall and winter of 1997. PM_(2.5) particles were collected on the pre-fired quartz filters for 24 hours and analyzed by the selective thermal oxidation method. The concentrations of OC at the sites were higher than those commonly observed from clean areas around the world, but those of EC at both sites were lower than, or comparable to, other clean areas in the world. Both the OC and EC levels at Kangwha were higher than those at Kosan. According to backward trajectory analysis, most air pollutants collected at thetwo sites were from China. It was found that the OC and EC concentrations in air masses from southern China were higher than those from northern China.

황해 직선 황로상 대기오염물질의 측정

이승복,배귀남,진현철,김영성,문길주,심상규 한국대기환경학회 2004 한국대기환경학회지 Vol.20 No.1

Air pollutants were measured eight times from June 1999 to June 2002 on regular ferries cruising across the Yellow Sea between Incheon in Korea and Qingdao or Tianjin in China. PM_(10) and PM_(2.5_ were measured as particulate matters and SO₂, CO, and NOx were measured as gaseous pollutants. On each route, sampling was made, starting two hour after departure and ending two hour before arrival. Low concentrations of gaseous pollutants that were not much varied according to sampling period and location revealed that atmosphere over the sea was not directly affected by anthropogenic emissions. However, concentrations of fine particles were generally higher than those measured at Deokjeok Island. 50 km west of the western seashore, at similar periods. It was believed that considerable influence of China in the form of secondary pollutants was exerted over the sea.

1997~2001년 제주도 고산지역 PM2.5 미세분진의 오염 특성

강창희,김원형,한진석,선우영,문길주 한국대기환경학회 2003 한국대기환경학회지 Vol.19 No.3

PM_(2.5) fine particles have been collected at the Gosan measurement station in Jeju Island, and the major water-soluble components have been analyzed in order to investigate the aerosol compositions and pollution characteristics. The mean concentrations of the components were in the order of SO₄²^(-) > NH₄^(-) > NO₃^(-) >Na¹ > K > Cl^(-) > Ca²^(+) > Mg²^(+). The major components were SO₄²^(-), NH₄^(-) and NO₃^(-), whose compositions were 58%, 18% and 10% of the total ions, respectively. Most of the components showed higher concentrations in spring season, and especially Ca²^(+), NO₃^(-) and SO₄²^(-) concentrations were increased 2.8, 1.9 and 1.2 times higher than the annual mean concentrations. The most parts of SO₄²^(-) and NH₄^(-) were distributed in the particles below 2.1μm size, but the Ca²^(+), Na^(+) and Cl^(-) showed relatively higher concentrations in coarse particles. Based on the factor analysis, the PM_(2.5) line particles were considered to be largely influenced by anthropogenic sources, and followed by sea salt and soil sources. In the variations of concentrations as a function of wind direction. Most components have shown higher concentrations natably as the northwesterly prevails.

초기 톨루엔 농도가 톨루엔-NO_(x)-공기 혼합물의 광산화 반응에 미치는 영향 : II. 입자상 물질의 생성 및 성장 II. Aerosol Formation and Growth

이영미,배귀남,이승복,김민철,문길주 한국대기환경학회 2005 한국대기환경학회지 Vol.21 No.1

An experimental investigation of the gas-phase photooxidation of toluene-NOx-air mixtures at sub-ppm concentrations has been carried out in a 6.9 ㎡, indoor smog chamber irradiated by blacklights. Measured parameters in the toluene-NO_(x) experiments included aerosol, O₃, NO, NO₂, NO_(x), CO, SO₂, toluene, and air temperature. The initial toluene concentration ranged from 225 ppb to 991 ppb and the initial concentration ratio of toluene/NOx in ppbC/ppb was in the range of 5~20. It was found that the variation of aerosol number concentration with irradiation time caused by the photooxidation of toluene-NOx-air mixtures depended on the initial toluene concentration for similar concentration ratio of toluene/NO_(x). The dependency of initial toluene concentration on the photooxidation of toluene-NO_(x)-air mixtures for toluene/NOx=5~6 seemed to be opposite to that for toluene/NO_(x)= 10~11. The maximum number concentration of aerosols formed by photooxidation and the aerosol yield depended on both initial toluene concentration and initial concentration ratio of toluene/NO_(x). In this study, the aerosol yield, defined as aerosol formed per unit toluene consumed, was found to be 0.01~0.16.

실내 스모그 챔버의 설계 및 성능평가

배귀남,김민철,이승복,송기범,진현철,문길주 한국대기환경학회 2003 한국대기환경학회지 Vol.19 No.4

A multi-functional indoor smog chamber was designed and evaluated lo investigate photochenical or water vapor reaction mechanisms of air pollutants. Various smog chamber experiments could be conducted using ambient air or purified air in this smog chamber. The smog chamber consisted of a housing, a Teflon bag, blacklights, injection ports, sampling ports, and utility facilities. The characteristics of light source, the wall losses of air pollutants, and the quality of purified air were experimentally investigated. The maximum NO₂ photolysis rate was 1.10min^(-1). In a 2.5-m³ Teflon bag, the wall losses of ambient O₃, NO, and NO₂were 1.2~2.4×10^(-3)min^(-1), 0.7~2.0×10^(-3)min^(-1), and 0.4-2.0×10^(-3)min^(-1), respectively. The wall loss of ambient particles ranging 0.05 to 0.2㎛ was 1.8~5.4×10^(-3)min^(-1), which was slightly higher than those of ambient gaseous species. The purified air supply system provided high quality of air with NO₂, < 1 ppb, and total hydrocarbons <5 ppb.

초기 톨루엔 농도가 톨루엔-NOx-공기 혼합물의 광산화 반응에 미치는 영향 : I. 가스상 물질의 변화 I. Change of Gaseous Species

이영미,배귀남,이승복,김민철,문길주 한국대기환경학회 2005 한국대기환경학회지 Vol.21 No.1

An experimental investigation of the gas-phase photooxidation of toluene-NO_(x)-air mixtures at sub-ppm concentrations has been carried out in a 6.9 ㎥, indoor smog chamber irradiated by blacklights. Measured parameters in the toluene-NOx experiments included O₃, NO, NO₂, NO_(x), CO, SO₂, toluene, and air temperature. The initial toluene concentration ranged from 225 ppb to 991 ppb and the initial concentration ratio of toluene/NOx in ppbC/ppb was in the range of 5~20. It was found that the variation of gaseous species with irradiation time caused by the photooxidation of toluene-NOx-air mixtures depended on the initial toluene concentration for similar concentration ratio of toluene/NOx. The dependency of initial toluene concentration on the photooxidation of toluene-NO_(x)-air mixtures for toluene/NOx =5~6 seemed to be opposite to that for toluene/NOx=10~11. The arriving time at maximum ozone concentration depended on both initial toluene concentration and initial concentration ratio of toluene/NOx. However, the maximum concentration of ozone formed by photooxidation depended only on the initial toluene concentration.