사례기반추론과 텍스트마이닝 기법을 활용한 KTX 차량고장 지능형 조치지원시스템 연구

이형일(Hyung Il Lee),김종우(Jong Woo Kim) 한국지능정보시스템학회 2020 지능정보연구 Vol.26 No.1

KTX rolling stocks are a system consisting of several machines, electrical devices, and components. The maintenance of the rolling stocks requires considerable expertise and experience of maintenance workers. In the event of a rolling stock failure, the knowledge and experience of the maintainer will result in a difference in the quality of the time and work to solve the problem. So, the resulting availability of the vehicle will vary. Although problem solving is generally based on fault manuals, experienced and skilled professionals can quickly diagnose and take actions by applying personal know-how. Since this knowledge exists in a tacit form, it is difficult to pass it on completely to a successor, and there have been studies that have developed a case-based rolling stock expert system to turn it into a data-driven one. Nonetheless, research on the most commonly used KTX rolling stock on the main-line or the development of a system that extracts text meanings and searches for similar cases is still lacking. Therefore, this study proposes an intelligence supporting system that provides an action guide for emerging failures by using the know-how of these rolling stocks maintenance experts as an example of problem solving. For this purpose, the case base was constructed by collecting the rolling stocks failure data generated from 2015 to 2017, and the integrated dictionary was constructed separately through the case base to include the essential terminology and failure codes in consideration of the specialty of the railway rolling stock sector. Based on a deployed case base, a new failure was retrieved from past cases and the top three most similar failure cases were extracted to propose the actual actions of these cases as a diagnostic guide. In this study, various dimensionality reduction measures were applied to calculate similarity by taking into account the meaningful relationship of failure details in order to compensate for the limitations of the method of searching cases by keyword matching in rolling stock failure expert system studies using case-based reasoning in the precedent case-based expert system studies, and their usefulness was verified through experiments. Among the various dimensionality reduction techniques, similar cases were retrieved by applying three algorithms: Non-negative Matrix Factorization(NMF), Latent Semantic Analysis(LSA), and Doc2Vec to extract the characteristics of the failure and measure the cosine distance between the vectors. The precision, recall, and F-measure methods were used to assess the performance of the proposed actions. To compare the performance of dimensionality reduction techniques, the analysis of variance confirmed that the performance differences of the five algorithms were statistically significant, with a comparison between the algorithm that randomly extracts failure cases with identical failure codes and the algorithm that applies cosine similarity directly based on words. In addition, optimal techniques were derived for practical application by verifying differences in performance depending on the number of dimensions for dimensionality reduction. The analysis showed that the performance of the cosine similarity was higher than that of the dimension using Non-negative Matrix Factorization(NMF) and Latent Semantic Analysis(LSA) and the performance of algorithm using Doc2Vec was the highest. Furthermore, in terms of dimensionality reduction techniques, the larger the number of dimensions at the appropriate level, the better the performance was found. Through this study, we confirmed the usefulness of effective methods of extracting characteristics of data and converting unstructured data when applying case-based reasoning based on which most of the attributes are texted in the special field of KTX rolling stock. Text mining is a trend where studies are being conducted for use in many areas, but studies using such text data are still lacking in an environm

Life Cycle Cost Prediction for Rolling Stocks in Maintenance Phase Based on VBA Language Program

Jiamin Fang,Lin Ji 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.3

In order to predict and analyze the LCC during rolling stocks’ maintenance phase, provide the important support for the decision during rolling stocks’ design, production, operation and disposal, mitigate the risks for high expenditure, the LCC prediction software is developed with VBA programming language in Microsoft Excel environment based on various rolling stocks’ maintenance scenarios. This software can collect the LCC input and predict the LCC during rolling stocks’ maintenance phase. The data input is based on the history data and RAMS information for each system and approved by the engineers. This software is validated by several systems and a specific metro project. It shows very wide applicability for LCC prediction for comparing and analyzing for customer and design and friendly interface to the users.

고속철도차량용 제빙액으로의 적용가능물질에 대한 융빙성능 평가

박경원 ( Gyoung-won Park ),이준구 ( Jun-ku Lee ),이홍기 ( Hong-ki Lee ) 한국공업화학회 2019 공업화학 Vol.30 No.3

동절기 고속철도차량 하부 및 대차부에 부착된 설빙이 차량 운행 시 도상자갈구간(침목이 받는 차량 하중 전달 및 침목 고정을 위한 자갈 구간)에서 고속으로 낙하하여 자갈을 비산시켜 이로 인한 철도차량 구조물 및 시설물의 피해가 보고되고 있으며, 이는 고속철도 개통 이후 지속되고 있다. 이러한 문제점 해결을 위해 자갈의 비산을 방지하는 네트, 인력 제빙, 이동식 열풍기 등을 사용하고 있으나 효율성이 떨어진다. 기존보다 효율적인 제빙을 위해 화학적 제빙액에 대한 연구가 진행되고 있으며, 본 연구에서는 화학적 제빙액으로 사용되는 물질들의 융빙성능, 동점도, 증발성 등을 평가하여 고속철도차량 제빙용으로 최적의 물질을 찾고자 한다. 평가 물질로는 유기산염류 4종(개미산나트륨, 초산나트륨, 개미산칼륨, 초산칼륨)과 알코올류 2종(프로필렌글리콜, 글리세롤)을 대상으로 하였다. 이때, 실내 평가에서는 개미산칼륨, 초산칼륨, 프로필렌글리콜이 유사한 융빙성능을 보였으나, 모사 살포 시스템을 이용한 융빙성능 결과, 프로필렌글리콜이 가장 우수한 성능을 보였다. 이는 프로필렌글리콜의 동점도가 2.989029 St로 다른 물질대비 높아 얼음에서 보다 오래 체류하여 제빙하기 때문이다. 또한, 개미산칼륨과 초산칼륨은 결정이 석출되어 차량외관에 악영향을 미치므로 사용에 어려움이 있다. 본 연구를 통해 프로필렌글리콜이 고속철도차량용 제빙액으로 최적의 물질임을 확인하였다. In winter season, the snow and ice accretion on the bottom of the high speed railway rolling stock and boogie part has fallen at a high speed from the ballast section (gravel section for the transmission of the rolling stock load received by sleepers and fixing sleepers), causing the gravel to be scattered, thereby damaging the railway rolling stock structures and facilities. In order to solve these problems, the gravel scattering prevention net, manual de-icing, and movable hot air machine were used, but their efficiency was low. For the more efficient de-icing than ever before, an optimum material for de-icing fluid for high speed railway rolling stock was developed by evaluating the ice melting capacity, kinematic viscosity, evaporation of the material used as a chemical de-icing fluid. Four kinds of organic acid salts (sodium formate, sodium acetate, potassium formate and potassium acetate) and two different alcohols (propylene glycol, glycerol) were used as evaluation materials. Potassium formate, potassium acetate, and propylene glycol had similar ice melting capacities in the indoor test, but the propylene glycol showed the best ice melting capacity in spraying the system simulation test. This is because the kinematic viscosity of propylene glycol was 2.989029 St, which is higher than those of other materials therefore, it could stay longer on the ice and de-icing. In addition, potassium formate and potassium acetate were difficult to be used since the crystals precipitated and adversely affected the appearance of the rolling stock. The propylene glycol is the most optimum as an de-icing fluid for the high speed railway rolling stock.

철도차량 LCC분석을 통한 경제적 내구연한 설정 연구

박수명(Park Su-Myung),김승태(Kim Seung-Tae) 한국철도학회 2009 한국철도학회 학술발표대회논문집 Vol.2009 No.11월

국내 철도차량의 내용연수는 철도운영사의 경영에 있어 중요한 요소이나 철도차량 사용의 중단 및 계속을 의미하는 내용연수의 결정이 운영사의 자율이 아닌 철도안전법상에 의해 규제를 받고 있어 운영사의 자율성을 침해하는 측면이 있어, 본 연구에서는 연구대상차량을 VVVF 전기동차로 한정하여, 외국의 도시철도운영사례를 검토하고, 대상차종을 가지고 LCC이론에 입각하여 전생애에 걸쳐 소요되는 비용을 산정하여 철도차량의 경제적 내구연한 산정방식에 맞춰 경제적 내구연한을 도출하고, 철도안전법에 의해 규정하고 있는 내구연한 기준과 본 연구를 통해 나타난 경제적 내구연한을 비교 검토하여 운영사의 입장에서 철도차량운영에 대한 장기적 전략 마련에 도움이 되고자 한다. The life-span of rolling stock is the kind of important component for train operating company, but in our country, life-span and scrutiny diagnosis are decided by railway safety raw, which is rare case difficult to find any example in the world and which also infringed on the operating autonomy in terms of companies. So selected specific kind of rolling stock(VVVF EMU) for analyzing target, and investigated the overseas metropolitan rolling stock examples, classified how many years cars used in other countries, and calculated the real cost of the selected cars based on the LCC(Life Cycle Cost) theory and decided the economical life-span of rolling stock. Through this study, I want to compare the life-span decided by law and the economical life span decided by this study and assist in preparing the long term strategy of rolling-stock usage for rolling stock company.

철도 전동차내의 쾌적성 평가에 관한 연구- 온도 및 습도를 중심으로 -

박덕신,배상호,정병철,이주열 한국철도학회 2003 한국철도학회논문집 Vol.6 No.1

Most of people spends their times in indoor about 85% of a day. Thus, indoor is more serious than outdoor concerned with the health. We discussed comfortableness in a railroad electric rolling stock, and focused on temperature and humidity. Electric rolling stock is one of major public transportation system because of an increasing in population and heavy traffic problems. The passengers are under the influence of indoor air quality such as air temperature, relative humidity and air velocity. Ventilation system in electric rolling stock should be designed for the health and comfort. One of the main aims is to create an acceptable thermal environment without draught problem. The draught sensation increases when the air temperature decreases and the air velocity increases. Airflow in electric rolling stock is turbulent. Temperature and humidity gradients in electric rolling stock have been studied. And, the difference between mean temperature and relative humidity measured at 0.7, 0.9, 1.2, 1.7 m above the floor. It has been found that temperature and relative humidity with large fluctuations caused more draught complaints.

철도차량 내부장치간 무선연계 및 배선절감 기술 성능평가를 위한 시험 인프라 구축과 운영방안의 수립

서경수(Kyoung-soo Seo),김영규(Young-gyu Kim),김홍봉(Hong-bong Kim),박세영(Se-Young Park),김영배(Young-bae Kim),강우철(Woo-chul Kang),김태인(Tea-in Kim) 한국철도학회 2016 한국철도학회 학술발표대회논문집 Vol.2016 No.10

철도차량 내부 장치간 무선연계 및 배선절감 연구는 철도차량의 순차 아날로그 제어 방식 내부배선을 디지털 제어방식 로직회로에 의한 무접점 스위치 및 통신방식으로 전환하기 위한 것으로 기존 배선을 30%이상 절감시키며 장치의 신뢰성 및 내환경성 그리고 차량 유지보수성을 향상시키는 것을 목적으로 한다. 배선절감 기술 연구는 차량의 로직회로 설계, 차량 내 네트워크, 차량 간 무선통신 등 다양한 기술이 적용되며 이러한 기술적용에 따라 정밀하고 효과적인 성능평가가 필요하다. 본 논문에서는 차량 내부간 무선연계 및 배선절감 기술의 성능평가를 위한 시험선과 시험차량의 선정부터 비용산출, 개조 등 시험 인프라 구축과 함께 시험선 운영의 전반적인 계획 및 방안을 제시하고자 한다. Rolling stock wiring reduction technology study is aimed at reduction more than 30% of rolling stock internal wiring for improve reliability and environmental resistance, and also analog control method sequential switching circuit are change to the solid state switch and communication system through the digital control logic circuit. These wiring saving technologies are applied a variety of techniques such as the wireless communication between the rolling stock car, logic circuit design, internal network, etc. so it needs a precise and effective performance evaluation. In this paper, we present overall plan and decision for rolling stock wiring reduction technology performance evaluation, and It’s includes an overall decision for evaluating the performance comprehensively. Such as testing railway selection, selection for testing train, calculate operation cost for testing, determination for inspection and maintenance period.

철도차량의 TSI 인증과 형식승인과의 비교

최강윤(Kangyoun Choe),김연수(Yeonsu Kim),홍재성(J. S. Hong),송민섭(M.S. Song),목재균(Jai Kyun Mok) 한국철도학회 2017 한국철도학회 학술발표대회논문집 Vol.2017 No.05

유럽은 2008년 철도시스템 상호운영지침을 개정하고, 2014년 고속철도와 일반철도를 통합한 기관차 및 객차에 대한 TSI를 제정하였다. 국내의 경우 2012년 12월 철도안전법이 전면 개정되며 철도차량과 용품의 형식승인제도가 운영 중에 있으며, 철도차량의 형식승인제도는 형식승인, 제작자승인, 완성검사의 3 단계로 이루어진다. 유럽의 TSI 인증 체계를 소개하며, 국내 형식승인제도와 비교한다. The European Community Revised the Interoperability directive in 2008 and legislate the Technical specification for interoperability to locomotives and passenger rolling stock’ subsystem in 2014. The MLIT of Korean government wholly amended the Railroad safety act in 2012, and enforced the type approval system for the rolling stock. The type approval scheme is composed of type approval scheme for rolling stock, manufacturer approval for rolling stock and completion inspection of rolling stock. The TSI certification system is introduced and compared with type approval system.

도시철도차량의 운행 특성에 따른 제동마찰재 유지보수 분석 연구

서경수(Kyoung-soo Seo),김영규(Young-gyu Kim),김홍봉(Hong-bong Kim),박세영(Se-Young Park),김계신(Kae-Shin Kim),강병훈(Byoung-Hun Kang),김인호(In-Ho Kim) 한국철도학회 2017 한국철도학회 학술발표대회논문집 Vol.2017 No.05

도시철도차량에서 기초 제동시스템인 공기제동은 차륜과 레일의 점착력으로 제동력을 얻는 점착 브레이크이다. 이는 차륜에 제동력을 직접 전달하는 방식으로 제동 마찰재를 차륜 답면에 밀어 붙이는 방식과 차축이나 차륜에 결합된 디스크에 라이닝을 밀어 붙이는 방식이 있다. 제동 마찰재는 차량 운행시 주행 안전성에 큰 영향을 미치는 부품으로 교환주기 및 소모량의 파악은 차량의 운행관리 및 유지보수 운영에 있어 매우 중요하다. 본 논문에서는 도시철도차량에서 사용되는 제동 슈와 라이닝 등 제동마찰재의 차량 종류에 따른 소모량 특성을 분석하여 도시철도 운영기관의 차량 운행관리, 유지보수 및 유지보수 자재관리 등 차량운영 전반에 대한 시사점을 제시하고자 한다. In urban railway rolling stock, air braking, which is the basic braking system, is an adhesive brake that obtains the braking force by the adhesion between the wheel and the rail. This is a way to push the braking friction material onto the wheel face in a manner that directly transmits the braking force to the wheel, or pushing the lining against the disk coupled to the axle and wheel. The braking friction material is a part that has a great influence on the driving safety when the rolling stock is running, and the identification of the replacement cycle and the consumption amount is very important for the operation management and maintenance of the rolling stock. In this paper, we analyze the consumption characteristics of braking friction materials and would like to suggest implications for the overall operation of the rolling stock, such as rolling stock operation management, maintenance and maintenance materials management of the urban railway operator.

DEA(자료포락분석)를 이용한 도시철도 전동차 운영효율 연구

서경수(Kyoung-soo Seo),안현미(Hyun-mi Ahn) 한국철도학회 2016 한국철도학회 학술발표대회논문집 Vol.2016 No.10

도시철도차량 운영에 있어서 차종의 선택과 도입, 유지보수정책 결정, 연장사용, 폐기 등의 의사결정은 차량운행의 안전성, 운행의 정시성, 고객서비스 등과 밀접하게 관련되어 있을 뿐만 아니라 차량 운영기간 전체의 수명주기비용을 결정하는 핵심 요소이기 때문에 중요하게 고려되어야 한다. DEA(자료포락분석)를 이용한 도시철도 전동차 운영 효율연구는 서울메트로 1호선에 운영되고 있는 2개 차종인 저항형 전동차와 VVVF전동차의 운영효율을 운행 및 유지보수 관련 자료를 바탕으로 DEA(자료포락분석)를 이용 분석하여 차종에 따라 유지보수 비용 및 운영효율이 어떠한 차이를 가지는지를 실증적으로 보여 준다. 이를 통해 차종 선택, 차량의 연장사용, 유지보수 정책의 수립, 유지보수 자재의 공급사슬 구축 및 관리 등 도시철도차량 운영과 관련된 전반적 의사결정에 시사점을 제시하고자 한다. In the urban railway rolling-stock operations the choice, extended use and disposal decisions of rolling-stock It should be carefully consider Because these decision are closely related as safety, operation punctuality and customer service. and also it’s a core component of life-cycle cost in entire rolling-stock operation period. In this study we present the empirical analysis result of Seoul Metro Line#1 rolling-stock’s operation efficiency using DEA in order to know what difference in effectiveness between rolling-stock model Type. This study provide implications for Entire Urban Railway Operation, railway vehicle Choice, Establishing Rolling stock Maintenance Policy and Build Supply Chain for Maintenance etc.

도시철도 차량 유지보수 운영효율 연구: 서울 도시철도 8호선을 중심으로

서경수,김용욱,윤화현,한재현,이동훈 한국철도학회 2019 한국철도학회논문집 Vol.22 No.9

Maintenance of rolling stock is a key activity in the operation of urban railways. Optimized maintenance iscrucial to maintaining cost-effectiveness, preventing failure, and maintaining urban rail service level. In this paper, weanalyzed the maintenance efficiency of rolling stock using DEA (Data Envelopment Analysis), focused on Seoul MetroLine #8. In addition, based on the DEA results, we analyzed the effect of system failure on the efficiency and foundthere were significant effects for failures of High Voltage, Brake, Bogie, Auxiliary Power Supply, Passenger AddressEquipment, Inverter Propulsion Equipment, Electric devices, and TCMS. Especially, it was confirmed that the occurrenceof faults in the Auxiliary Power Supply, Bogie, and High Voltage equipment has a relatively large effect on efficiency. This study provides implications for the prevention of certain equipment failure of rolling stock, showing that itis important to maintain the service level of operational rolling stock and the urban railway.