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  • Title/Summary/Keyword: Vehicle inspection

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The Distribution of the Normal Traffic Loads on the Steel Plate Girder Bridge (실동하중에 의한 강판형교의 교통하중 분포)

  • Woo, Sang-Ik;Jung, Kyoung-Sup
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.4 no.2
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    • pp.103-111
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    • 2000
  • The objectives of the study are to know the strain distribution and modal dynamic behaviour of steel bridge girders by actual traffic load. The live load effect depends on many parameters including the span length, gross vehicle weight, axle weight, axle configuration so on. For the estimation of static and dynamic characteristic, strain data caused by moving loads and traffic characteristics of passing vehicle under actual traffic load have measured using Bridge Weigh in Motion. To confirm the reliability of BWIM system, strain data measured using the 120Ω strain gauge under the same condition. It is considered that the data acquired from BWIM system have reliability through the analysis and comparison between stress measured by strain data from BWIM and computed by FEM. Additionally according to the measured strain data of up-line and down-line on the highway, the up-line bridge grows more faster than the down-line bridge and girder 4 and 5 carry more load when vehicles pass the inner line and girder 2 and 3 does when vehicles pass the outer line as this case(the bridge composed with 5 girders).

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A vision-based system for inspection of expansion joints in concrete pavement

  • Jung Hee Lee ;bragimov Eldor ;Heungbae Gil ;Jong-Jae Lee
    • Smart Structures and Systems
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    • v.32 no.5
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    • pp.309-318
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    • 2023
  • The appropriate maintenance of highway roads is critical for the safe operation of road networks and conserves maintenance costs. Multiple methods have been developed to investigate the surface of roads for various types of cracks and potholes, among other damage. Like road surface damage, the condition of expansion joints in concrete pavement is important to avoid unexpected hazardous situations. Thus, in this study, a new system is proposed for autonomous expansion joint monitoring using a vision-based system. The system consists of the following three key parts: (1) a camera-mounted vehicle, (2) indication marks on the expansion joints, and (3) a deep learning-based automatic evaluation algorithm. With paired marks indicating the expansion joints in a concrete pavement, they can be automatically detected. An inspection vehicle is equipped with an action camera that acquires images of the expansion joints in the road. You Only Look Once (YOLO) automatically detects the expansion joints with indication marks, which has a performance accuracy of 95%. The width of the detected expansion joint is calculated using an image processing algorithm. Based on the calculated width, the expansion joint is classified into the following two types: normal and dangerous. The obtained results demonstrate that the proposed system is very efficient in terms of speed and accuracy.

The Effect of Dual Clutch Transmissions on the Stability Emissions Characteristic in a Gasoline Direct Injection Engine (GDI 엔진에 DCT 적용에 따른 배기 배출물 특성에 미치는 영향)

  • Kim, Kwang Lae;Roh, Hyun Gu
    • Journal of ILASS-Korea
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    • v.20 no.3
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    • pp.156-161
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    • 2015
  • This paper described the effect of dual clutch transmissions on the stability emissions characteristic in a GDI engine at vehicle Inspection and Maintenance(I/M) program. In order to investigate the influence of direct injection gasoline engine with DCT, the experimental apparatus consisted of GDI engine with 4 cylinder, dynamometer and exhaust emissions analyzer. Analyzed emission gas include CO, HC and NOx results that DCT vehicle in the case of NOx, HC in automatic transmission vehicles less than 1/2 level was confirmed to be exhausted. However vehicle specific power increases CO also has increased.

An intelligent control system design for autonomous underwater vehicle (무인 수중운동체를 위한 지능제어시스템 설계)

  • Lee, Dong-Ik;Kwak, Dong-Hoon;Choi, Jung-Lak
    • Journal of Institute of Control, Robotics and Systems
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    • v.3 no.3
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    • pp.227-237
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    • 1997
  • Autonomous Underwater Vehicles(AUVs) have become an important tool for various purposes in subsea: inspection, recovery, construction, etc., and the development of autonomous control system is luglay desirable- thete zffe many problems associated with designing the control system for AUV due to unknown underwater envimn-Tnent, the possibility of subsystem failures, and unpredictable changes in the dynamics of the vehicle. In this paper, an autonomous control system based on the intelligent control theory to enhance operation efficiency of the ALTV is presented. The control system has a hierarchical structure which consists of mission planning level, mission control level, navigation level, and execution level. The performance of the control system is investigated by computer simulation. The results show that the proposed control system can be applied successfully to the AUV in spite of the possibility of failures in the vehicle and the collision hazard in the sea environment.

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Development of P-SURO II Hybrid Autonomous Underwater Vehicle and its Experimental Studies (P-SURO II 하이브리드 자율무인잠수정 기술 개발 및 현장 검증)

  • Li, Ji-Hong;Lee, Mun-Jik;Park, Sang-Heon;Kim, Jung-Tae;Kim, Jong-Geol;Suh, Jin-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.9
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    • pp.813-821
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    • 2013
  • In this paper, we present the development of P-SURO II hybrid AUV (Autonomous Underwater Vehicle) which can be operated in both of AUV and ROV (Remotely Operated Vehicle) modes. In its AUV mode, the vehicle is supposed to carry out some of underwater missions which are difficult to be achieved in ROV mode due to the tether cable. To accomplish its missions such as inspection and maintenance of complex underwater structures in AUV mode, the vehicle is required to have high level of autonomy including environmental recognition, obstacle avoidance, autonomous navigation, and so on. In addition to its systematic development issues, some of algorithmic issues are also discussed in this paper. Various experimental studies are also presented to demonstrate these developed autonomy algorithms.

Flaw Evaluation of Bogie connected Part for Railway Vehicle Based on Convolutional Neural Network (CNN 기반 철도차량 차체-대차 연결부의 결함 평가기법 연구)

  • Kwon, Seok-Jin;Kim, Min-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.11
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    • pp.53-60
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    • 2020
  • The bogies of railway vehicles are one of the most critical components for service. Fatigue defects in the bogie can be initiated for various reasons, such as material imperfection, welding defects, and unpredictable and excessive overloads during operation. To prevent the derailment of a railway vehicle, it is necessary to evaluate and detect the defect of a connection weldment between the car body and bogie accurately. The safety of the bogie weldment was checked using an ultrasonic test, and it is necessary to determine the occurrence of defects using a learning method. Recently, studies on deep learning have been performed to identify defects with a high recognition rate with respect to a fine and similar defect. In this paper, the databases of weldment specimens with artificial defects were constructed to detect the defect of a bogie weldment. The ultrasonic inspection using the wedge angle was performed to understand the detection ability of fatigue cracks. In addition, the convolutional neural network was applied to minimize human error during the inspection. The results showed that the defects of connection weldment between the car body and bogie could be classified with more than 99.98% accuracy using CNN, and the effectiveness can be verified in the case of an inspection.

On the Occurrence of Defects by Vehicle Type According to the Fire-fighting Vehicle Detailed Inspection (소방차량 정밀점검 분석에 따른 차종별 결함 발생에 관한 연구)

  • Lee, Jang Won;Han, Yong-Taek
    • Journal of the Society of Disaster Information
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    • v.17 no.1
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    • pp.112-119
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    • 2021
  • Purpose: This study is based on the detailed inspection data for the last 6 years of fire-fighting high ladder vehicles, fire-fighting inflected ladder vehicles, fire-fighting chemical vehicles and fire-fighting pump vehicles used in front-line fire departments. The purpose is to contribute to the technological development of fire-fighting vehicles by grasping the implementation status of each city and province, the rate of defects, and the occurrence of defects by year. Method: The implementation status by city and province, defect incidence rate, and defect occurrences by year were analyzed. Result: From 2012 to 2017, when the average of 230 or more overhaul vehicles was requested, the results of each city/province show slight fluctuations, but the number of defects gradually decreased due to the old fire-fighting vehicle replacement project and the response of fire vehicle manufacturers. Conclusion: In the case of fire-fighting ladders, the incidence rate of defects was found to be in the order of elevator device, electric device, ladder device, and pneumatic supply device. And in the case of the fire fighting ladder, it was confirmed that the incidence of defects appeared in the order of the refractive ladder, hydraulic cylinder, hydraulic oil, and pneumatic supply device. In the case of fire-fighting chemical vehicles, it was confirmed that defects occurred in the powder fire extinguishing device, fire pump, vacuum pump, and pneumatic supply device.

Analysis on the Characteristics of Hazardous Chemical Transport Vehicle Accidents in Korea (국내 유해화학물질 운송차량사고 특성분석)

  • Jeong, Jae-uk;Lee, Sang-jae
    • Journal of the Society of Disaster Information
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    • v.16 no.2
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    • pp.310-317
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    • 2020
  • Purpose: In this study, the characteristics of hazardous chemical transport vehicle accidents during the last six years from 2014 to 2019 was analyzed. This study is to prevent chemical transport accidents. Method: Using statistics from the Ministry of Environment, chemical transport vehicle accidents were classified into accident type, accident cause and vehicle type. Result: Of the total 506 cases chemical accidents, 105 cases were caused by transport vehicle. More than 20 percent of total accidents were reported. Most of the accidents were caused by spill·leak. The main causes of the accident were traffic accidents(49 cases) and management negligence(29 cases). This was more than 74% of all transport vehicle accidents. By vehicle type, 57 cases(54%) were most common in tank lorries, followed by trucks (39 cases, 37%) and trailers (9 cases, 9%). Conclusion: In order to prevent accident of transport vehicle, thorough inspection of the transport vehicle is required and safe operation of the driver. In addition, the government needs to expand real-time monitoring of transport vehicles and comprehensively manage different systems by the relevant ministries.

Automation of Inventory Checking System for Outdoor Warehouse (야외창고 재고실사 자동화를 위한 시스템 개발)

  • Bae, Sung Moon;Han, Kwan Hee;Lee, Hwa Yong;Hong, Kum Suk
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.41 no.3
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    • pp.138-144
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    • 2018
  • Inventory inspection is an important task to eliminate the inconsistency between real assets and inventory management systems, and it is performed periodically at the site. In the case of a large-sized property, it is mainly managed in an outdoor workshop or a warehouse. However, due to the large area of the outdoor area, it is relatively difficult to identify the quantity and location of the property and is also vulnerable to theft. To solve this problem, we proposed a method and system for performing a warehouse inventory inspection using an unmanned aerial vehicle (UAV) and Bluetooth low energy (BLE) beacons. The proposed method has the following advantages. First of all, if we carry out inventory inspection by utilizing UAV, we can minimize user's effort compared to existing methods. The method of recognizing the asset by attaching the BLE beacon is more costly than using the existing RFID technology, but it is advantageous because the recognition distance is increased and the battery life of the tag is drastically increased. We also designed a BLE beacon reader for the system and implemented a prototype to show the feasibility of the proposed system. The prototype is based on Genuino 101, which is a kind of arduino, and adds HM-10 and Neo-6m modules to provide Bluetooth and GPS functions. The BLE beacon reader was tested in outdoor, and attached in drone. We also developed an inventory checking system based on the web to display results of inventory checking. The proposed approach enables the users to automate the operation of inventory checking on an outdoor warehouse.

Practical Model to Estimate Road User Cost for Bridge Maintenance Strategy (교량 유지관리 전략 수립을 위한 실용적 도로이용자비용 추정 모델)

  • Park, Kyung-Hoon;Sun, Jong-Wan;Lee, Sang-Yoon;Lee, Jong-Soon;Cho, Hyo-Nam
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.11 no.6
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    • pp.131-142
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    • 2007
  • The road user cost in indirect costs as well as direct costs such as the inspection/ diagnosis cost and the repair/reinforcement cost should be considered as one of the important items in the life-cycle cost-effective design and maintenance of the bridges. To estimate the road user cost, this paper formulates the road user cost as a sum of the user delay cost and the vehicle operating cost considering the detour effect. A numerical traffic simulation and a regression analysis are performed to develop a regression model due to a time delay. The proposed regression model is applied to the generation of the maintenance strategy based on the life-cycle cost and performance, and its effectiveness and applicability is investigated. The road user cost has a great influence on establishing the maintenance strategy, and the proposed regression model could be successfully utilized to estimate the road user cost of a bridge.