• Title/Summary/Keyword: 한계조건

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A Study on Chemical Composition of Fine Particles in the Sungdong Area, Seoul, Korea (서울 성동구 지역 미세먼지의 화학적 조성에 관한 연구)

  • 조용성;이홍석;김윤신;이종태;박진수
    • Journal of Environmental Science International
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    • v.12 no.6
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    • pp.665-676
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    • 2003
  • To investigate the chemical characteristics of PM$\_$2.5/ in Seoul, Korea, atmospheric particulate matters were collected using a PM$\_$10/ dichotomous sampler including PM$\_$10/ and PM$\_$2.5/ inlet during the period of October 2000 to September 2001. The Inductively Coupled Plasma-Mass Spectromety (ICP-MS), ion Chromatography (IC) methods were used to determine the concentration of both metal and ionic species. A statistical analysis was performed for the heavy metals data set using a principal component analysis (PCA) to derived important factors inherent in the interactions among the variables. The mean concentrations of ambient PM$\_$2.5/ and PM/sub10/ were 24.47 and 45.27 $\mu\textrm{g}$/㎥, respectively. PM$\_$2.5/ masses also showed temporal variations both yearly and seasonally. The ratios of PM$\_$2.5/PM$\_$10/ was 0.54, which similar to the value of 0.60 in North America. Soil-related chemical components (such as Al, Ca, Fe, Si, and Mn) were abundant in PM$\_$10/, while anthropogenic components (such as As, Cd, Cr, V, Zn and Pb) were abundant in PM2s. Total water soluble ions constituted 30∼50 % of PM$\_$2.5/ mass, and sulfate, nitrate and ammonium were main components in water soluble ions. Reactive farms of NH$_4$$\^$+/were considered as NH$_4$NO$_3$ and (NH$_4$)$_2$SO$_4$ during the sampling periods. In the results of PCA for PM$\_$2.5/, we identified three principal components. Major contribution to PM$\_$2.5/ seemed to be soil, oil combustion, unidentified source. Further study, the detailed interpretation of these data will need efforts in order to identify emission sources.

Effect of Interaction between Nutritional Level and Breed on Performance of Broiler Production (BROILER 사료의 영양수준이 육용계종의 산육능력에 미치는 영향)

  • 오봉국;오세정
    • Korean Journal of Poultry Science
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    • v.6 no.1
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    • pp.12-23
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    • 1979
  • This experiment was carrid out to investigate the interaction between boilelr strains and nutrition levels, and the performances of four broiler strains such as Han Hyup 603, Hubbard, Anak and Filch when they were fed by four different nutrition levels (High Protein and energy; HP. HE., Medium Protein and energy; MP. ME., Low Protein ana energy; LP. LE., and low protein and energy; LLP. LLE.). The data used in this study were obtained from a total of 1200 broiler type chicks in Poultry Testing Station, Korean Poultry Association from June 16, to August 11, 1978. Differences of all characters among four nutrition levels were significant except viability and carcass rate. HP. HE and MP. ME treatments showed nearly the same performances in body weight, feed efficiency and point, spread but they were significantly superior to those of LP. LE and LLP. LLE. There were not significant differences among four strains in feed efficiency and viability but other characters, body weight, point spread and carcass rate were observed that the performance of the best strain B was significantly superior to strain D but it was not recognized significance compared with strain A, C in tile result of statisticel analysis. In the interaction between strains and nutrition levels, body weight at high and levels showed significantly differences but at low and low nutrition levels were nearly same among four strains. Therefore this study demonstrated that comparision of body weights between strains should be performed at medium nutrition level or above. Also point spread calculated as index of body weight and feed efficiency was observed that strain B at low nutrition level is excellently higher than other strains and there were little differences at low nutrition level among all strains. It was found that ]it tie differences between performances of high arid medium levels seemed to be as the reason of high fat addition for energy source to high mutrition feed, and in general superior strain showed good performance at all the nutrition levels in$.$all characters but in body weight and point spread there were significantly different responses with different nutrition level, The most superior strain B among four strains earned the most profit per bird, Although performances of high and medium nutrition levels were nearly the same, medium nutrition level also showed the most profit because the feed cost of high nutrition level was higher than that of medium nutrition level.

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Selective determination of mercury (II) ion in aqueous solution by chemiluminescence method (화학발광법에 의한 수용액 중의 선택적 수은(II) 이온 정량)

  • Kim, Kyung-Min;Jang, Taek-Gyun;Kim, Young-Ho;Oh, Sang-Huyb;Lee, Sang-Hak
    • Analytical Science and Technology
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    • v.24 no.4
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    • pp.243-248
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    • 2011
  • A selective determination method of mercury (II) ion in aqueous solution by luminol-based chemiluminescence system (luminol CL system) has been developed. Determination of metal ions such as copper (II), iron (III), chromium (III) ion in solution by the luminol CL system using its catalytic role in the reaction of luminol and hydrogen peroxide has been reported by several groups. In this study, the catalytic activity of mercury (II) ion in the reaction of luminol and hydrogen peroxide was observed by the enhanced CL intensity of the luminol CL system. Based on this phenomenon, experimental conditions of the luminol CL system were investigated and optimized to determine mercury (II) ion in aqueous solution. While mercury (II) ion in mixed sample solution containing mercury (I) and (II) ions highly enhanced the CL intensity of the luminol CL system, the mercury (I) ion could not enhanced the CL intensity. Thus selective determination of the mercury (II) ions in a mixture containing mercury (I) and (II) ions could be achieved. Each concentration of mercury (I) and (II) ions in aqueous solution can be obtained from the results of the CL method that give the concentration of only mercury (II) ion and the inductively coupled plasma (ICP) method that give the total concentration of mercury ions. On the optimized conditions, the calibration curve of mercury (II) ion was linear over the range from $1.25{\times}10^{-5}$ to $2.50{\times}10^{-3}M$ with correlation coefficient of 0.991. The detection limit of mercury (II) ion in aqueous solution was calculated to be $1.25{\times}10^{-7}M$.

A comparative analysis of gas and liquid phase standard spiked solid sorbent tubes for the determination of volatile organic compounds in indoor air by TD-GC/MS (열탈착/저온농축-GC/MS에 의한 실내공기 중 휘발성 유기화합물 정량용 기체상 및 액체상 표준물질 첨가한 고체 흡착관의 비교 분석)

  • Lim, Hyun-Woo;Jung, Sung-Won;Kang, Chul-Ho;Park, Jin-Sook;Park, Byeong Moo;Choi, Yong-Wook
    • Analytical Science and Technology
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    • v.26 no.4
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    • pp.287-297
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    • 2013
  • The optimization of analytical method for the thermal desorption of seven VOCs (volatile organic compounds) by TD-GC/MS (thermal desorption-gas chromatograph-mass spectrometer) with solid phase sorbent tube, and comparative analysis for the determination of VOCs plotted by standard sorbent tubes prepared using both gas phase and liquid phase materials were investigated. The result of paired t-test showed that a liquid phase standard sorbent tube method was in agreement with a gas phase standard sorbent tube method for six species of VOCs including benzene, toluene, ethylbenzene, o-, m-, and p-xylene except for styrene at the significance level (${\alpha}=0.01$), while the 15.6% of difference in response factor between both of gas phase and liquid phase standard plotting for the determination of styrene showed that both methods were significantly different at the significance level. Therefore, the liquid phase standard plotting method was employed to reduce erroneous data for the determination of styrene including BTEX. Under the optimized analytical method by liquid phase standard sorbent tube, recovery was between $100{\pm}5%$ for 7 species of VOCs, reproducibility ranged from 0.3 to 7.7%, and method detection limit (MDL) ranged from $0.01{\mu}g/m^3$ for o-xylene to $0.27{\mu}g/m^3$ for toluene. The optimized standard method was applied to determine VOCs VOCs from indoor air of of dormitory, one bedroom apartment, and a new car.

On the field of domestic studies on Western Art History and Western Art Theory (국내 서양미술사, 서양미술이론 연구 장에 관한 연구)

  • Shim, Sang-Yong
    • The Journal of Art Theory & Practice
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    • no.2
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    • pp.75-120
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    • 2004
  • Studies on western art in Korea has been caught in a dilemma that they could deal with only those things which had been arranged according to their 'historical generalization' in their contexts because of the bounds of time and space. It is not trivial that such conditions affect art studies in Korea. Access to the original texts and to their contexts of production is so restricted that the studies on them are prone to he superficial. And it is not independent on the politics of Korean art scene. Such factors are on the background of Korean art's excessive 'assimilation or accordance' with western art. The domestic studies on western art history and art theory have failed to notice the differences in context and Korean art has simply mediated or reproduced the restricted information by those studies. Also the studies on western art in Korea have been made use of as a justifying method of one's own academic domains. In such situations we should lead the studies on western art history and western art theory to a more reflective direction and confirm that the studies should not have any privileges of the realities. And we should try to reform a scholarship which participates in our life and existence. The field of domestic studies on western art history and western art theory should free itself from the invention of objectivity or the neutrality of mechanical reading and turn its eyes to the realities of life where events happens. Constantly suggesting which way Korean art and world art should go has to be the field's new coordinates.

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Optimization of Single-stage Mixed Refrigerant LNG Process Considering Inherent Explosion Risks (잠재적 폭발 위험성을 고려한 단단 혼합냉매 LNG 공정의 설계 변수 최적화)

  • Kim, Ik Hyun;Dan, Seungkyu;Cho, Seonghyun;Lee, Gibaek;Yoon, En Sup
    • Korean Chemical Engineering Research
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    • v.52 no.4
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    • pp.467-474
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    • 2014
  • Preliminary design in chemical process furnishes economic feasibility through calculation of both mass balance and energy balance and makes it possible to produce a desired product under the given conditions. Through this design stage, the process possesses unchangeable characteristics, since the materials, reactions, unit configuration, and operating conditions were determined. Unique characteristics could be very economic, but it also implies various potential risk factors as well. Therefore, it becomes extremely important to design process considering both economics and safety by integrating process simulation and quantitative risk analysis during preliminary design stage. The target of this study is LNG liquefaction process. By the simulation using Aspen HYSYS and quantitative risk analysis, the design variables of the process were determined in the way to minimize the inherent explosion risks and operating cost. Instead of the optimization tool of Aspen HYSYS, the optimization was performed by using stochastic optimization algorithm (Covariance Matrix Adaptation-Evolution Strategy, CMA-ES) which was implemented through automation between Aspen HYSYS and Matlab. The research obtained that the important variable to enhance inherent safety was the operation pressure of mixed refrigerant. The inherent risk was able to be reduced about 4~18% by increasing the operating cost about 0.5~10%. As the operating cost increases, the absolute value of risk was decreased as expected, but cost-effectiveness of risk reduction had decreased. Integration of process simulation and quantitative risk analysis made it possible to design inherently safe process, and it is expected to be useful in designing the less risky process since risk factors in the process can be numerically monitored during preliminary process design stage.

A Study on Establishing the presidential Library through Elevating the Status of the Government Archives and Records Service (대통령기록관의 설립 및 정부기록보존소의 위상에 관한 연구)

  • Kim, Sung-Soo;Suh, Hye-Ran
    • Journal of Korean Society of Archives and Records Management
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    • v.2 no.1
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    • pp.41-66
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    • 2002
  • This paper examines urgent issues of establishing the presidential library in relation to the current standing of the Government Archives and Records Service. As government records have been tremendously accumulated every year, the Government Archives and Records Service will be full within three years, which indicates that the constructing of new storage repositories is an emergent issue. In addition, presidential records are one of the most significant and influential public properties for preserving historical value and interpretation at the national level. Some serious concerns relating to the presidential library are raised for consideration. First of all, it is compulsory to preserve presidential records and to construct the presidential library. Second, the presidential library performs a variety of functions including the acquisition, preservation, access, reference, research, education, and display of presidential records as well as exhibits of public activities and administration personally and in public during the president' regime. A new presidential library should function as both of a depository and museum of presidential records through systematic arrangement and display. Thus a new repository of the Government Archives and Records Service should be co-constructed with the presidential library within the same boundary. Third, a newly constructed presidential library should be at least double- or triple- sized more than estimated in order to contain all related holdings. Fourth, to take custody of public records across the legislature, judiciary and administration, the Government Archives and Records Service should be directed by an official at the level of vice-minister and upgraded to an independent office such as "National Archives and Records Administration." Fifth, the presidential library's location and surrounding environments should be selected with careful planning.

A Study on Load-carrying Capacity Design Criteria of Jack-up Rigs under Environmental Loading Conditions (환경하중을 고려한 Jack-up rig의 내하력 설계 기준에 대한 연구)

  • Park, Joo Shin;Ha, Yeon Chul;Seo, Jung Kwan
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.1
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    • pp.103-113
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    • 2020
  • Jack-up drilling rigs are widely used in the offshore oil and gas exploration industry. Although originally designed for use in shallow waters, trends in the energy industry have led to a growing demand for their use in deep sea and harsh environmental conditions. To extend the operating range of jack-up units, their design must be based on reliable analysis while eliminating excessive conservatism. In current industrial practice, jack-up drilling rigs are designed using the working(or allowable) stress design (WSD) method. Recently, classifications have been developed for specific regulations based on the load and resistance factor design (LRFD) method, which emphasises the reliability of the methods. This statistical method utilises the concept of limit state design and uses factored loads and resistance factors to account for uncertainly in the loads and computed strength of the leg components in a jack-up drilling rig. The key differences between the LRFD method and the WSD method must be identified to enable appropriate use of the LRFD method for designing jack-up rigs. Therefore, the aim of this study is to compare and quantitatively investigate the differences between actual jack-up lattice leg structures, which are designed by the WSD and LRFD methods, and subject to different environmental load-to-dead-load ratios, thereby delineating the load-to-capacity ratios of rigs designed using theses methods under these different enviromental conditions. The comparative results are significantly advantageous in the leg design of jack-up rigs, and determine that the jack-up rigs designed using the WSD and LRFD methods with UC values differ by approximately 31 % with respect to the API-RP code basis. It can be observed that the LRFD design method is more advantageous to structure optimization compared to the WSD method.

보건관리대행기관 산업간호사의 업무수행과 직무만족도에 관한 연구

  • Jo, Dong-Ran;Go, Bong-Ryeon
    • Korean Journal of Occupational Health Nursing
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    • v.2
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    • pp.26-39
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    • 1992
  • 본 연구는 보건관리대행기관에 근무하는 산업간호사들의 보건관리업무실태 및 근무만족도와 이들간의 관계를 파악함으로써, 산업간호업무향상 및 효율적인 산업보건관리를 위한 기초자료로 제시하고자 시도되었다. 조사대상은 38개 보건관리대행기관중 24개 기관에 근무하는 산업간호사 118명중 97명을 대상으로 하였다. 연구기간은 '92년 5월부터 6월까지 설문조사를 실시하였으며 그중 89명이 설문에 응답하여 이를 분석 대상으로 하였다. 연구결과는 다음과 같다. 첫째, 보건관리대행기관의 간호사는 산업간호사의 일반적 특성과 비교해볼 때 기존 산업간호사와 유사하였다. 그러나 법정휴가를 받는다는 간호사가 59.1%로 더 낮았다. 둘째, 보건관리대행기관 산업간호사의 담당사업장수는 법적으로 30개 사업장, 2,000명의 근로자를 담당하도록 되어있는데 조사결과 법적기준인 보건관리사업장의 수를 담당하는 간호사는 57.1%를 차지하였고, 담당 근로자 수로 볼때는 2,000명이하가 29.8%를 차지하여 많은 산업간호사가 법적인 기준을 초과하여 산업보건관리를 대행하고 있는 것으로 나타났다. 셋째, 보건관리대행의 방문방법으로 교통편은 대행 기관차량을 이용하며, 간호사 혼자 산업장을 방문하는 것이 대부분으로 나타났고, 방문횟수는 100인미만이 월1회, 100인이상이 월2회로 규정된 것과 비교해보면 규정을 따르는 곳이 100인 미만의 경우 97.4%, 100인이상의 경우 86.4%였다. 또한 의사나 위생사는 방문을 안하거나 년1-5회 방문하는 것으로 나타나 보건관리대행의 주제공자는 간호사인 것으로 냐타났다. 또한 사업장 방문시 업무수행장소는 휴게실이나 사무실이 87.5%, 현장이나 수위실에서 하는 곳이 70.5%나 되어 뚜렷이 업무를 수행할 장소가 마련되지 않은 실정을 나타냈다. 네째, 보건관리대행에 근무하는 산업간호사의 애로사항은 사업장내에서는 조직과 체계상의 문제, 간호사 역할에 대한 인식부족, 권한과 자율성 부족 등을 들었고, 사업장 방문시에는 사업주와 근로자의 인식부족이 우선적으로 지적되었다. 또한 산업간호사는 보건관리 대행업무에서 사업장의 참여유도, 사업장 순회점검 및 개선지도, 보건교육, 건강상담이 우선적으로 실시되어야 한다고 하였다. 다섯째, 보건관리대행기관 산업간호사의 업무수행정도는 건강검진이나 직업병관리, 보건교육, 환경위생관리업무를 비교적 많이 실시하는 것으로 나타났다. 여섯째, 보건관리대행기관 산업간호사의 직무만족도는 전문적 위치나 상호작용, 업무요구등은 높게 나타났으나 보수와 산업보건관계자와의 관계등은 만족도가 낮게 나타났다. 또한 직무만족도에 대한 총화점수는 사업장근무자가 240점중 143.8인데 비해 보건관리대행기관 근무자는 230점중 129.61점으로 더 낮게 나타났다. 일곱째, 일반적 특성별 보건관리대행 산업간호사의 직무수행정도는 연령별 30세이상군이, 결혼상태별로 기혼군이, 경력은 1년이상인 군이, 근무시간 8시간인군이, 급여수준은 50만원이상인군이, 법정휴가가 있는 군이, 자질향상교육을 받은군이 담당사업장수가 30개이하인 군이, 더 높게 나타났다. 또한 연령군이 20-24군과 30세이상인군 (p<0.05), 결혼상태별로 기혼군과 미혼군(p<0.01), 급여수준별로 50만원미만군과 이상인 군(p<0.05), 법정휴가가 있는 군과 없는군(p<0.05), 자질향상 교육을 받은군과 받지못한 군(p<0.01), 담당사업장수가 30이하인 군과 31인이상인 군(p<0.05) 간에 유의한 차이를 보였다. 즉 산업간호사중 나이가 많고, 기혼이며 급여수준이 높고 법정휴가와 교육을 받고, 담당사업장수가 30이하인 군이 보건관리대행업무를 잘 수행하는 것으로 나타났다. 여덟째, 일반적 특성별 보건관리대행 산업간호사의 직무만족도는 연령별 30세이상군이, 결혼상태별로 기혼군이 경력은 1년이상인 군이, 근무시간 8시간인군이, 급여수준은 50만원이상군이, 법정휴가가있는군이, 자질향상교육을 받은군이, 담당사업장수가 30개이하인 군이 더 높게 나타났다. 또한 결혼상태별로 기혼군과 미혼군(p<0.01), 근무시간별로 8시간군과 9시간 이상인 군(p<0.01), 급여수준별 50만원 미만군과 이상군(p<0.05), 자질향상교육을 받은군과 받지 않은군(p<0.05) 사이에 유의한 차이를 보였다. 즉 산업간호사중 기혼이고 근무시간은 8시간이며 급여수준이 높고 자질향상교육을 받은 군이 만족도가 높은 것으로 나타났다. 아홉째, 보건관리대행기관 산업간호사의 업무수행정도와 직무만족도 사이의 상관관계를 보면 보수, 자율성, 업무요구가 높을수록 산업간호업무를 수행을 잘하는 것으로 나타났으며(상관관계 r>0.6, P>0.001), 전체적으로 총직무만족도와 업무수행정도와의 상관관계는 6346, P<0.001로서 만족도가 높을수록 업무수행정도가 높은 것으로 나타났다. 이상의 결과를 토대로하여 보면, 보건관리대행기관에 근무하는 산업간호사는 그 특성을 고려하여 업무도 사업장 근무자와 다르게 규정되어야 하며, 담당업무의 명확한 한계를 정해 중소규모사업장의 산업보건관리업무를 책임있게 수행할 수 있도록 뒷받침이 필요하다. 더불어, 직무만족도를 높일수 있도록, 산업간호사에 대한 다방면의 지원이 필요하다고 하겠다. 또한 보건관리대행기관 산업간호사는 나이가 많고 기혼이며 경력있는 간호사를 채용하고 근로조건을 잘 개선하면 직무수행정도가 더 높아질 것으로 보인다. 좋은 근로조건의 형성과 직무만족도 등을 높여 산업간호사의 직무를 효율적으로 수행할 수 있도록 하기 위하여는 보건관리대행기관에 관한 규정이 강화 보완되어야 하겠으며, 민간단체와 의료기관 뿐아니라 공공기관에서도 중소규모사업장의 보건관리업무를 담당하는 방향으로 전환하는 방안을 모색해 보아야 할 것이다.

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Evaluation of Incident Detection Algorithms focused on APID, DES, DELOS and McMaster (돌발상황 검지알고리즘의 실증적 평가 (APID, DES, DELOS, McMaster를 중심으로))

  • Nam, Doo-Hee;Baek, Seung-Kirl;Kim, Sang-Gu
    • Journal of Korean Society of Transportation
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    • v.22 no.7 s.78
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    • pp.119-129
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    • 2004
  • This paper is designed to report the results of development and validation procedures in relation to the Freeway Incident Management System (FIMS) prototype development as part of Intelligent Transportation Systems Research and Development program. The central core of the FIMS is an integration of the component parts and the modular, but the integrated system for freeway management. The whole approach has been component-orientated, with a secondary emphasis being placed on the traffic characteristics at the sites. The first action taken during the development process was the selection of the required data for each components within the existing infrastructure of Korean freeway system. After through review and analysis of vehicle detection data, the pilot site led to the utilization of different technologies in relation to the specific needs and character of the implementation. This meant that the existing system was tested in a different configuration at different sections of freeway, thereby increasing the validity and scope of the overall findings. The incident detection module has been performed according to predefined system validation specifications. The system validation specifications have identified two component data collection and analysis patterns which were outlined in the validation specifications; the on-line and off-line testing procedural frameworks. The off-line testing was achieved using asynchronous analysis, commonly in conjunction with simulation of device input data to take full advantage of the opportunity to test and calibrate the incident detection algorithms focused on APID, DES, DELOS and McMaster. The simulation was done with the use of synchronous analysis, thereby providing a means for testing the incident detection module.