• Journal of Korean Society of Steel Construction
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• v.13 no.3
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• pp.313-325
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• 2001

Tubular bridge rail was developed to restrain and redirect a 14ton van-type truck. The developed bridge rail permits better visibility than concrete safety-shape bridge rail, and it has better structural adequacy than the existing steel and aluminum bridge rails in Korea. The new bridge rail consists of a tubular thrie beam(TTB) rail and a steel guard rail, which are connected to composite posts. The TTB shape provides both better containment of diverse bumper heights and more tight fit between the ends of bridge rail and roadside guardrails than the existing bridge rail sections currently used in Korea. Making composite post by filling concrete inside the steel pipe of the same size as are used for the roadside guardrail post was found to be more efficient in increasing the stiffness and ultimate strength than simply increasing the size of the steel pipe. The system was crash-tested for the impact condition of 14ton-80km/h-$15^{\circ}$, and it satisfied all evaluation criteria set forth in NCHRP Report 350 for a Test Level 4 safety appurtenance. Acceptable performances were obtained in computer simulations for the impact condition of S2.

• Journal of Navigation and Port Research
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• v.31 no.8
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• pp.717-723
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• 2007

In recent years, the transportation sector has been undergoing very rapid and multifarious changes due to the M&A, alliances between shipping companies, introduction of larger container ship as it cost reduction measure and the application of integrated logistics to satisfy the needs of customers. Therefore, container terminal is required adequate terminal facilities, sufficient channel depth, efficient handling and low cost of port fees and dues. The purpose of this paper is for functional assessment of efficient container terminal. Firstly, the container operating process information about yard equipment and chassis is extracted through the analysis of practical daily work report of container terminal. Also, the formulae of skill factor and troubles of operator on transfer crane are defined. Lastly, container handling simulation model which consideration of skill factor and trouble of operator is proposed by Petri network model.

• Tunnel and Underground Space
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• v.26 no.4
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• pp.253-265
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• 2016

In this study, travel time data collection of mine equipments was conducted in an underground mine using a reverse Radio Frequency IDentification (RFID) system. In the reverse RFID system, RFID readers and antennas are mounted on mine equipments, and RFID tags are attached to the underground mine gallery. Indoor experiments were performed to analyze how RFID reader transmission power levels affect tag readable area and tag recognition rates. The results showed that travel time measurement become precise when the reader transmission power was reduced, however tag recognition rates were reduced. The field experiments indicated that setting the reader transmission power to 28 dBm maintained the tag recognition rate while minimizing the tracking location error. In addition, the results revealed that the reverse RFID system can be used successfully in an underground mine to collect the travel time data of haulage trucks.

• Journal of Korean Society of Transportation
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• v.29 no.6
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• pp.117-128
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• 2011

In this study, a model is developed to predict emission factors, which aims to objectively evaluate the impact of transport projects on air quality. Two emission prediction models for the years of 2015 and 2030 are developed using the historical trends in vehicle aging and vehicle deterioration factors. The analysis results show that the emission factors under the operating speed of 30km/h for the year 2030 are 5~37% and 2~83% less than those used in the current studies for passenger cars and bus/trucks, respectively. The statistically validated experiment results demonstrate the applicability of the proposed model to evaluation of the impact of transport policies on air quality.

• Journal of Intelligence and Information Systems
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• v.12 no.3
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• pp.47-65
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• 2006

These days, the number of automated container terminals is increasing to encourage the productivity of the container terminal inside and outside of the country. So far, there have been a lot of researches on the operating one type of equipments in a container terminal. However, there is still room for further improvement as none of equipment works itself but cooperate each other to finish a job, which means synchronization among the equipments is necessary. Among lots of equipments in a terminal, this paper concerns with the operation of ATCs (Automated Transfer Crane) and YTs (Yard Truck). The purpose of this paper is to find the efficient heuristic methods for operating ATCs and YTs that can set up a schedule in a real time. Moreover, using simulation this paper shows the efficient stacking strategy to decide the location of containers to be put and the proper selection range of YTs.

• Journal of Korea Multimedia Society
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• v.12 no.10
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• pp.1478-1485
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• 2009

A sensor network which is composed of a large number of sensors that perform various sensing is applied in a variety of fields. The sensor networks can be widely used for various application area like as home automation, fire detection and security area. Development of new sensor to have appropriate functions and deployment of networks for suitable application are served actively. In this paper, we design and implement a system that monitors various factory facilities by deploying sensor network at a working place which threatens the worker's safety. A sensor node reports its sensing data like as temperature and humidity to monitor facilities to a sink node. And the server which is connect to the sink node gathers and provides information by user interface. In addition, digital data which are generated at a work place can be transferred via the sensor network to increase the efficiency of works. The proposed sensor network provides the convenience of working, since it is deployed at a garbage collection company to monitor a temperature and humidity of garbage and to transmit data about the weight of trucks which enters the company.

• International Journal of Highway Engineering
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• v.6 no.4 s.22
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• pp.123-136
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• 2004

This study tries to compare the noise difference by various surface treatments and to propose appropriate tinning methods. As literature reviews, longitudinally tined pavement is effective to reduce noise made between tire and pavement surface. Various surface treatments were applied to some sections of test road. In case of car, about 2$\sim$3dB(A) was reduced in the section of uniform space 18mm longitudinal tinning. The peak frequency point for truck case happened between 200 and 600 Hz. The maximum noise of car was measured at about 1000Hz. Therefore, it Is proved that surface treatment methods can have a large affect on noise generation. With a result that friction test, the transverse tined pavement showed better frictional characteristics than the longitudinally tined pavement, but as a whole it came out satisfactory result. Results from this study are of early age, so it is required to check the performance continuously.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.5
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• pp.173-187
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• 2018

This paper proposes a computer vision and deep learning-based technique for surveillance camera system for vehicle counting as one part of parking lot management system. We applied the You Only Look Once version 2 (YOLOv2) detector and come up with a deep convolutional neural network (CNN) based on YOLOv2 with a different architecture and two models. The effectiveness of the proposed architecture is illustrated using a publicly available Udacity's self-driving-car datasets. After training and testing, our proposed architecture with new models is able to obtain 64.30% mean average precision which is a better performance compare to the original architecture (YOLOv2) that achieved only 47.89% mean average precision on the detection of car, truck, and pedestrian.

• Journal of Korean Society of Steel Construction
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• v.23 no.3
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• pp.397-404
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• 2011

In this paper, a research for the dynamic wheel loads of a 3D vehicle model, which relates to a tire-enveloping model, is carried out. A single truck with four axles is modeled as a 10-D.O.F. vehicle by modeling both contact length of tires and pitching of tandem spring axles. The dynamic equations of the vehicle are obtained using the Lagrange's equation, the solution of the equations is calculated by Newmark-${\beta}$ method. The validity of the developed 3D vehicle model is demonstrated by comparing results obtained from the proposed method with those from experimental data. The maximum impact factors of tire force are evaluated according to the various step bumps on which a 24-ton dump truck is running.

• Journal of Environmental Science International
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• v.22 no.9
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• pp.1105-1113
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• 2013

This paper attempted to estimate the emissions of HFC-134a from scrap truck as a result of measuring the residual quantities of HFC-134a in air conditioner of scrap truck. We measured the residual amounts in the scrap truck of 138 by applying commercial recover for refrigerants. The average residual rate(disposal-phase emission factor) is reported to be $44.3{\pm}3.3%$ within a confidence interval of 95%. Recent year model trucks exhibit the higher residual rates. Little variation, however, is observed in regard to vehicle size. The HFC-134a emission quantity from scrap truck in 2011 is estimated to be 55,908 $tCO_2$-eq that demonstrates 21.4% increase to compare with that in 2007. As the numbers of truck have increased dramatically during the last two decades, the emissions of HFC-134a from scrap truck would increase sharply in the next coming years. HFC-134a is a very high GWP greenhouse gas. therefore have to reduce the emissions from the scrap truck and need to find ways to recycle. The chemical compositions of refrigerants from scrap truck are quite similar to those of new refrigerants, suggesting that the refrigerants from scrap truck could be reused as refrigerant.