• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.18-21
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• 1996

This paper deals with experimentation on static test of linear induction motor for the propulsion system of UTM(Urban Transit Maglev). It is very important that vertical force zero effects to levitation field of maglev. Because it is continuous for air gap 11mm of levitated maglev vehicle. Then we found the slip frequency that the vertical force zero due to it is variable. Thus we had compared between simulation value and experiment value for lim by static test Jig.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.1
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• pp.130-138
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• 2015

Despite of recently strengthened vehicle emission regulations, NOx emissions are not decreased in urban areas because of discrepancies between certification emission test modes and real driving conditions. Thus, researches on RDE-LDV (Real-driving Emission-Light-duty Vehicle) have been conducted actively using PEMS (Portable Emissions Measurement Systems). In the present study, NOx emissions were measured for 5 Korean light duty vehicles for real driving conditions including city, combined, highway, and up-downhill test route. Emission characteristics were analyzed for averaged NOx emissions per unit driving distance of each driving test routes. Furthermore, MAW (Moving Average Window) method based on $CO_2$ emissions from WLTC, which will be supported for EU regulations, was utilized. It was revealed that DRs (deviation ratios) for diesel vehicles (i.e., 5.1 ~ 8.4) were greater than gasoline vehicles (less than 0.15). Especially DR of diesel vehicle for up-downhill test route was 8.4, which indicates severe NOx emissions.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.7
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• pp.3100-3116
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• 2016

With the rapid development of urban traffic system and fast increasing of vehicle numbers, the traditional centralized ways to generate the source-destination shortest path in terms of travel time(the optimal path) encounter several problems, such as high server pressure, low query efficiency, roads state without in-time updating. With the widespread use of smart cameras in the urban traffic and surveillance system, this paper maps the optimal path finding problem in the dynamic road network to the shortest routing problem in the smart camera networks. The proposed distributed optimal path generation algorithm employs the delay routing and caching mechanism. Real-time route update is also presented to adapt to the dynamic road network. The test result shows that this algorithm has advantages in both query time and query packet numbers.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1140-1141
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• 2006

Maglev is a non-contact traffic system in which cars are supported by magnetic force instead of wheels. This is a ground-breaking traffic system providing superior environmental friendliness and cost efficiency due to the minimal noise and vibration offered by its non-contacting nature. We study the present specification and performance of the low speed urban maglev system in Korea and other countries. After set up the test line, to success the "Commercialization of Korean Urban Maglev System" project, we establish proper requirement of maglev system in Korean environment on base of "Daejeon National Science Museum Maglev Establish Project".

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.682-684
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• 2002

There is much room for consideration that the magnet design of UTM. When the vehicle runs 60mR curved line on test track, the ratio of cross section area changed to cross the magnet pole and rail. The ratio is reduced about 20% of the total magnet on one bogie. Therefor, magnet current is increased about 3.5A to maintain constant air gap. This paper suggest to margin of the magent design is 1.1 rather than rated levitation force.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.413-415
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• 2001

A railroad vehicle(Light weight electric rail car, Urban railroad, High-speed railroad) need to construct propulsion- system capacity experiment equipment to test performance or to estimate confidence. Experiment equipment in interior have been used Flywheel which is equal to the same inertia as railroad straight moment. But mechanical inertia using flywheel don't change inertia and can't embody traveling-struggle which is similar to actual traveling-struggle. We propose the method to embody electric railroad load system with inertia using electric servo motor in order to get the characteristic of real vehicle load, and confirm this algorithm with simulation and experiment.

• Proceedings of the KSR Conference
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• 2000.05a
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• pp.55-62
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• 2000

The status of the maglev development in Korea is reported along with related commercial application prospects. The 1st test vehicle, Urban Transit Maglev-01, is in the running tests, and is now entered a new phase in which a new vehicle be built within 3 years. Eventhough Korean maglev teams made remarkable progress for 10 years since 1990, major portion of the works to prove safety and reliability remains for the future. Many LRT routes are being planned by the Korean government and UTM will find its commercial application if we can prove many merits of the maglev system plus its reliability. But the commercial application efforts did not produce any outcome at the time because the customer wasn't totally satisfied with the new system and also, they decided it wasn't urgently needed.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.1
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• pp.1-9
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• 2017

In this study, a test-bed system simulated a tunnel and concrete track is tested on cite and invested an allowed limit of multi-layered sound absorbing panel for reducing noise reflected on the concrete track in train tunnel considering the criteria and limitation on the theoretical back ground. The studied results are an effective evaluating system of the sound absorbing coefficient influenced fluid effects depending on the vehicle speed in the urban train tunnel and measuring not only structural behaviors of maximum displacement and acceleration of the panel but also dynamic characteristics of damping ratio and natural frequency.

• Journal of the Korean Institute of Gas
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• v.20 no.5
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• pp.64-71
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• 2016

According to the urban gas business law, electrical corrosion prevention measures shall be installed to the buried gas pipelines and the pipe-to-soil potentials should be measured at the test box at least once a year. Most of the test boxes installed in urban area are usually located on the road where the vehicle travels, therefore, it is difficult to measure the CP potentials at the test boxes. That is, we need traffic control when carrying out the measurement of the CP potentials on daytime when the traffic is heavy, or we have to measure the potentials in the late night when the traffic is light. To solve these difficulties, we have studied remotely CP potential measuring method by using the patrol car. We have installed solid reference electrodes and data loggers under the test boxes on the site and received the CP potentials from the data loggers when the vehicle moves. It was difficult to send and receive the data because the data logger was located under the ground. We have applied 3 different method including 2 antenna systems to achieve best effective way in receiving the data. We have found the remote CP measuring method by using a car can save more 20 times of measuring time than conventional measuring methods.

• Journal of the Korean Association of Geographic Information Studies
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• v.4 no.3
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• pp.51-60
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• 2001

The travel behavior can be analysed microscopically using GPS because the travel characteristics can be found out by travelling two test cars loaded with GPS equipments. The speed difference and spacing variation between the lead vehicle and the following's in uninterrupted flow are the important variables related to capacity and safety. This study analysed these with data obtained by travelling the 4th Line and 28th Line of the national road. The variation width in speed difference in the run time is below 3.0%. But, related to the speed difference in the situation of acceleration and deceleration the difference after 4second is bigger than that just after the start. The spacing variation is similar to this. The spacing just before deceleration concerning safety was analysed. When the theoretical values by the modeling method and observed values were compared, the observed values were analysed 12.52% shorter than the other in average.