• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.35 no.4
• /
• pp.897-905
• /
• 2015

This research suggested the traffic signal calculation model of active transit signal priority using a shockwave model. Using this signal priority timing optimization model, the shockwave area is computed under the condition of Early Green and Green Extension among active transit signal priority techniques. This study suggested the speed estimation method of backward shockwave using average travel time and intersection passing time. A shockwave area change is calculated according to signal timing change of transit signal priority. Moreover, this signal timing calculation model could determine the optimal signal priority timings to minimize intersection delay of general vehicles. A micro simulation analysis using VISSIM and its user application model ComInterface was applied. This study checked that this model could calculate the signal timings to minimize intersection delay considering saturation condition of traffic flow. In case studies using an isolated intersection, this study checked that this model could improve general vehicle delay of more over ten percentage as compared with equality reduction strategy of non-priority phases. Recently, transit priority facilities are spreading such as tram, BRT and median bus lane in Korea. This research has an important significance in that the proposed priority model is a new methodology that improve operation efficiency of signal intersection.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2005.05b
• /
• pp.821-825
• /
• 2005

본 연구에서는 홍수조절 용 저수지의 예비방류 시행을 충분히 효과적으로 시행하고 강우종료 후에도 충분한 이수용량이 확보되도록 실시간 강우자료를 이용한 저수지 유입량 예측모형을 개발하였다. 사전예보(기상청 등)에 의한 총 예상강우량과 선행강우량, 현재 저수지 수위를 입력자료로 저수지 유입 총량과 수위변화량을 계산하여 홍수조절 응 저수지의 초기수위저하 및 하류 하도의 홍수방어를 사전에 대비할 수 있는 자료를 제시하였다. 또한, 유역을 하나의 통합시스템으로 구성하고 실제 강우가 시작되면 매시간 현시간 이후 강우가 중단된다는 가정 하에 현시점까지의 우량주상도를 통합시스템에 적용하여 이후 저수지 유입량을 예측하였다. 무한천 예당저수지에 적용하였으며 통합시스템의 구성은 저수지유역을 10개 소유역으로 분할하고 소유역별 홍수유출량은 Clark의 유역추적법, 하도구간은 Muskingum의 하도홍수추적 방법으로 계산되도록 하였다. 그리고 홍수유출시스템 내에는 강우관측소별 티센가중치에 따라 소유역별 평균강우량이 자동으로 입력되도록 하였으며, 예측정확도를 위해 현시간 이전까지 매시간마다 저수지의 수위변동과 실제 방류량으로부터 실측유입량을 산정하여 모형의 매개변수가 자동 보정되도록 하였다. 1995년 8월 23일$\~$8월 26일과 1999년 8월 2일$\~$8월 4일의 집중호우에 대하여 적용한 결과 모형의 예측정확도는 신뢰수준에 있었으며, 이와 같은 자료는 장수형 등(2005)이 제시한 효율적 저수지 운영관리 시스템과 하나로 통합되어 하류 하도의 통수능력을 고려한 홍수방어능력을 극대화한 예비방류의 시행과 강우종료 후에도 이수용량에는 손실이 없는 저수지의 관리방안의 지침이 되는데 효율적이라 판단되었다. 방법을 개발하여 개선시킬 필요성이 있다.>$4.3\%$로 가장 근접한 결과를 나타내었으며, 총 유출량에서도 각각 $7.8\%,\;13.2\%$의 오차율을 가지는 것으로 분석되어 타 모형에 비해 실유량과의 차가 가장 적은 것으로 모의되었다. 향후 도시유출을 모의하는 데 가장 근사한 유출량을 산정할 수 있는 근거가 될 것이며, 도시재해 저감대책을 수립하는데 기여할 수 있을 것이라 판단된다.로 판단되는 대안들을 제시하는 예비타당성(Prefeasibility) 계획을 수립하였다. 이렇게 제시된 계획은 향후 과학적인 분석(세부평가방법)을 통해 대안을 평가하고 구체적인 타당성(feasibility) 계획을 수립하는데 토대가 될 것이다.{0.11R(mm)}(r^2=0.69)$로 나타났다. 이는 토양의 투수특성에 따라 강우량 증가에 비례하여 점증하는 침투수와 구분되는 현상이었다. 경사와 토양이 같은 조건에서 나지의 경우 역시 $Ro_{B10}(mm)=20.3e^{0.08R(mm)(r^2=0.84)$로 지수적으로 증가하는 경향을 나타내었다. 유거수량은 토성별로 양토를 1.0으로 기준할 때 사양토가 0.86으로 가장 작았고, 식양토 1.09, 식토 1.15로 평가되어 침투수에 비해 토성별 차이가 크게 나타났다. 이는 토성이 세립질일 수록 유거수의 저항이 작기 때문으로 생각된다. 경사에 따라서는 경사도가 증가할수록 증가하였으며 $10\% 경사일 때를 기준으로 $Ro(mm)=Ro_{10}{\times}0.797{\times}e^{-0.021s(\%)}$로 나타났다.천성 승모판 폐쇄 부전등을 초래하는 심각한 선천성 심질환이다. 그러나 진단 즉시 직접 좌

• Journal of Korean Medical classics
• /
• v.13 no.2 s.17
• /
• pp.58-67
• /
• 2000

통과대문왕팔괘차서도화문왕팔괘방위도적연구(通過對文王八卦次序圖和文王八卦方位圖的硏究). 득도요여하결론(得到了如下結論). 1. 최초명명위문왕팔괘차서도화문왕팔괘방위도적인시소옹(最初命名爲文王八卦次序圖和文王八卦方位圖的人是邵雍). 문왕팔괘차서도화문왕팔괘방위도수연몰유시문왕소화적확체적근거(文王八卦次序圖和文王八卦方位圖雖然沒有是文王所畵的確切的根據), 단시종추연복희이(但是從推演伏羲易), 동사상결합(同事相結合), 최종확립여금적역학체계적인시문왕(最終確立如今的易學體系的人是文王). 이차환부합현금적역리(而且還符合現今的易理), 인차구유일정설복력(因此具有一定說服力). 2. 재문왕팔괘차서도중삼남유일양이음구성(在文王八卦次序圖中三男由一陽二陰構成). 삼녀유일음이양구성(三女由一陰二陽構成). 저가이용음양호근적원리진행설명(這可以用陰陽互根的原理進行說明). 3. 복희팔괘방위도현시모종공간상(伏羲八卦方位圖顯示某種空間相). 이문왕팔괘방위도칙현시사시(而文王八卦方位圖則顯示四時). 팔절적변화화만물생장적류행주기등시간상적변화(八節的變化和萬物生長的流行周期等時間上的變化). 4. 문왕팔괘방위도동사시적오행상일치(文王八卦方位圖同四時的五行相一致). 시상생관계(是相生關係), 팔괘당중각유양개목김토(八卦當中各有兩개木金土). 시유우형흔왕성(是由于形흔旺盛), 수화각유일개시유우기흔왕성(水火各有一개是由于氣흔旺盛). 5. 문왕팔괘방위도재표면상간호상시오행상생적관계(文王八卦方位圖在表面上看好象是五行相生的關係). 단시(但是), 상호성대면적팔괘적오행도성상극관계(相互成對面的八卦的五行都成相剋關係). 화동측상임적감수(和東側相臨的坎水) 간토(艮土) 진목(震木) 손목도시성상극관계(孫木都是成相剋關係). 종차가이지도상극시발전만물적주체(從此可以知道相剋是發展萬物的主體). 6. 대우복희팔괘전화위문왕팔괘적원리(對于伏羲八卦轉化爲文王八卦的原理), 수유각종이론제출(雖有各種理論提出). 단시상무확체적설법(但是尙無確切的說法). 7. 복희팔괘주요체현천도화외상등(伏羲八卦主要體現天道和外象等), 문왕팔괘측체현인사화내정등(文王八卦側體現人事和內情等). 8. 복희팔괘위체(伏羲八卦爲體), 문왕팔괘위용(文王八卦爲用). 복희팔괘중(伏羲八卦中), 위변화적주체적천지즉건곤위우중축(爲變化的主體的天地卽乾坤位于中軸). 문왕팔괘중(文王八卦中), 위변화적대용적일월즉감리위우중축(位變化的大用的日月卽坎離位于中軸). 9. 복희팔괘도속우표현춘천적변화지상적제일괘도(伏羲八卦圖屬于表現春天的變化之象的第一掛圖), 생괘도화창조도(生掛圖和倉曹圖), 문왕팔괘도칙속우표현하천적변화지상적제이괘도(文王八卦圖則屬于表現夏天的變化之象的第二掛圖), 장괘도화발전도(長掛圖和發展圖). 10. 문왕팔괘도시류행이치기용적역지용(文王八卦圖是流行以致其用的易之用), 표현무질서화혼란(表現無秩序和混亂), 위화여괴리상호란무적난음난양지상(韋和與乖離相互亂舞的亂陰亂陽之象). 11. 문왕팔괘도화낙서적변화원리상일치(文王八卦圖和洛書的變化原理相一致), 가이장낙서적수직접대응도문왕팔괘도중(可以將洛書的數直接對應到文王八卦圖中). 우명낙서팔괘도(又名洛書八卦圖). 구수도혹일구역(九數圖或一九易). 12. 문왕팔괘도적상대응적수자지합도위십(文王八卦圖的相對應的數字之合都爲十). 저예시료성괘도십수도적출현(這豫示了成掛圖十數圖的出現).

• Journal of Korean Society of Transportation
• /
• v.18 no.4
• /
• pp.7-18
• /
• 2000

KS-SIGNAL, a traffic signal optimization model for coordinated arterials, is an optimization model using the mixed integer linear Programming that minimizes total delay on arterials by optimizing left-turn Phase sequences. However, the Previous version of KS-SIGNAL had a difficulty in reducing computation speed because the related variables and constraints multiply rapidly in accordance with the increase of intersections. This study is designed to propose a new model, improving optimizing computation speed in KS-SIGMAl, and evaluate it. This Paper Puts forth three kinds of methodological approaches as to achieve the above goals. At the first step to reduce run-time in the proposed model objective function and a few constraints are Partially modified, which replaces variable in related to queue clearance time with constant, by using thru-movements at upstream intersection and the length of red time at downstream intersection. The result shows that the run-time can be reduced up to 70% at this step. The second step to load the library in LINDO for Windows, in order to solve mixed integer linear programming. The result suggests that run-time can be reduced obviously up to 99% of the first step result. The third step is to add constraints in related to left-turn Phase sequences. The proposed methodological approach, not optimizing all kinds of left-turn sequences, is more reasonable than that of previous model , only in the view of reducing run-tim. In conclusion, run-time could be reduced up to 30% compared with the second results. This Proposed model was tested by several optimization scenarios. The results in this study reveals that signal timing plan in KS-SIGNAL is closer to PASSER-II (bandwidth maximizing model) rather than to TRANSYT-7F(delay minimizing model).

• Journal of the Korean Association of Geographic Information Studies
• /
• v.11 no.3
• /
• pp.52-67
• /
• 2008

Recently, frequent occurrence of flash floods caused by climactic change has necessitated prompt and quantitative prediction of precipitation. In particular, the usability of rainfall radar that can carry out real-time observation and prediction of precipitation behavior has increased. Moreover, the use of distributed hydrological model that enables grid level analysis has increased for an efficient use of rainfall radar that provides grid data at 1km resolution. The use of distributed hydrologic model necessitates grid-type spatial data about target basins; to enhance reliability of flood runoff simulation, the use of visible and precise data is necessary. In this paper, physically based $Vflo^{TM}$ model and ModClark, a quasi-distributed hydrological model, were used to carry out flood runoff simulation and comparison of simulation results with data from Imjin River Basin, two-third of which is ungauged. The spatial scope of this study was divided into the whole Imjin River basin area, which includes ungauged area, and Imjin River basin area in South Korea for which relatively accurate and visible data are available. Peak flow and lag time outputs from the two simulations of each region were compared to analyze the impact of uncertainty in topographical parameters and soil parameters on flood runoff simulation and to propose effective methods for flood runoff simulation in ungauged regions.

• International Commerce and Information Review
• /
• v.13 no.2
• /
• pp.205-234
• /
• 2011

The study analyzes the shifts of international competition in the digital products market between South Korea and major FTA partners. The analysis utilizes trade statistics to calculate changes in the volume of trade, and in competitiveness between FTA partners. The target countries for this analysis include USA and the European Union with whom Korea has made agreements recently, and the period is set for the decade from 2000 to 2009. The trade records of the UN are employed to investigate the indexes of each country: trade structure and market share of digital products, the trade specialization index (TSI), and annual change of revealed comparative advantage index (RCA) against global market and both the American and EU markets. This analysis shows clearly the status quo of the development and growth of the international competitiveness of South Korea. The study will improve the understanding of international competitiveness in digital products and contents industry, which is rapidly evolving, and of the resulting industrial structure.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.12 no.4
• /
• pp.11-21
• /
• 2013

The conventional real-time signal control strategy for oversaturated situation generally requires a number of detectors at the intersection in order to identify the queue length at each approach. Also, existing strategy for the spillback has limited effect due to the temporal spillback control which only reduce the green split at the approach. In this study, a signal control system utilizing the imagery information from ITS roadside equipment is developed for operation of oversaturated intersections. The strategy calculates the saturation ratio based on the queue length extracted from ITS RSE, and designs the signal control variables according to the saturation ratio. The signal control strategy is divided into two phases: oversaturated and supersaturated. In oversaturated conditions, timing plan for main approach is optimized by the queue length. In oversaturated conditions where spillback might occur, the signal timing is designed in order to avoid the spillback. To increase field adaptability, the strategy is designed to adjust the split length, all-red-time, and clearance time, and keep the major signal control variables intact. The result of the simulation shows that in oversaturated conditions, the improvement is similar to the real-time signal control system. In case of, oversaturated conditions, however, the effect of the strategy is superior to that of a real-time system.

• The Journal of the Korea Contents Association
• /
• v.16 no.4
• /
• pp.347-358
• /
• 2016

ICT sector has been made a great deal of achievements for past 20 or more years in the aspects of the industrial promotion and the efficiency improvement under the strong leadership by the government for the informatization and still leads the Korean industries. However, the previous studies are mostly on how the quantitative growth of patents impacts a company's management achievements while being insufficient on the qualitative level. In this study, an analysis is attempted on the impact from the qualitative level of patents held by a ICT company leading Korean industry to its management achievements. In other words, if the concentration of technological innovation activities, a scale to measure the qualitative level of possessed patents is influential to the growth and the profit of a company is analyzed. The analysis result shows that the current time technological superiority index, RTA and the concentration index, CRn of the technological innovation activities significantly impact to the growth and the profit of company. This study demonstrates the positive impact from a highly qualitative level of patents to the growth and the profit of a company in ICT sector in the current circumstance of insufficient researches on the qualitative level of patents. Therefore, this study is expected to present a new start point for the future studies.

• Journal of Korean Society of Transportation
• /
• v.21 no.2
• /
• pp.119-130
• /
• 2003

SP data have been widely used in assessing new transport policies and transport related plans. However, one of criticisms of using SP is that respondents may show different reaction between hypothetical experiments and real life. In order to overcome the problem, combination of SP and RP data has been suggested and the combined methods have been being developed. The purpose of this paper is to suggest a new SP and RP combined method using error component method and to verify the method. The error component method decomposes IID extreme value error into non-IID error component(s) and an IID error component. The method estimates both of component parameters and utility parameters in order to obtain relative variance of SP data and RP data. The artificial SP and RP data was created by using simulation and used for the analysis, and the estimation results of the error component method were compared with those of existing SP and RP combined methods. The results show that regardless of data size, the parameters of the error component method models are similar to those assumed parameters much more than those of the existing SP and RP combined models, indicating usefulness of the error component method. Also the values of time for error component method are more similar to those assumed values than those of the existing combined models. Therefore, we can conclude that the error component method is useful in combining SP and RP data and more efficient than the existing methods.

• Journal of the Economic Geographical Society of Korea
• /
• v.15 no.1
• /
• pp.77-94
• /
• 2012

The purpose of this study is to analyze the process of vertical fragmentation of regional industries in Korea using Revealed Comparative Advantage index (RCA) and Average Propagation Length (APL). First of all, the competitiveness in regional export and substitution of regional imports were strong in the Electricity, Gas, and Water supply sector in Gyeongnam, and consumer-oriented Manufacturing sector in Incheon, Gyeongnam, and Gwangju. The high values of the APL were also found in the regions with common similarity with respect to the industrial structure and the sectors with indirect effects. In addition, the industrial sectors with high quality of infrastructure, and endowed services tended to be located in the beginning of the production chain. FInally, since manufacturing and service sectors in Seoul has higher APL, they could lead the growth of other related industries as key sectors, in the production fragmentation.