• Journal of Korean Society of Transportation
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• v.19 no.3
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• pp.133-144
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• 2001

The purpose of this study is to develop micro simulation model for large-scale network with driver's behavior model. This study is performed for uninterrupted flow road section. And this model is developed to simulate traffic flow of the real network with unique geometric structure. The vehicle transmission and drivers' behavior model based on the exiting Cellular Automata approach.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1138-1142
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• 2005

The tidal river is a river affected by tide, which causes the water level to rise and fall two times everyday periodically. The local velocity across the river could be very fast because of the cross-sectional characteristics of the river even though it's not a rainy season. Therefore extreme local scour could take place around hydraulic structures such as piers and caissons due to backward flow velocity. For the construction of pier foundation of Ilsan-bridge In the Han River, the field observations were performed to get the velocity and water level. The numerical analysis was performed by HEC-RAS(UNET). The relationship between measured maximum velocity and calculated mean velocity is achieved, which is used to estimate the velocity and water level as the construction is proceeding. Countermeasures for scour were designed with the results of the hydraulic analysis to avoid potential damage during construction work. According to the results of monitoring, the velocity increase after temporary road embankment was negligible, from which it is considered that the degradation of main channel compensated for the constriction of cross-section by embankment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.12
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• pp.2619-2625
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• 2011

The GPS technique widely used recently in car navigation system has two problems that are unavailability in urban canyons and inherent positional error rate. The one has been studied and solved in many literatures. However, the other still leads to incorrect locational information in some area, especially parallel roads. This paper proposes and implements a system to recognize lane of moving vehicle based on images obtained from in-vehicle networks or other devices. The proposed system utilizes a real-time image matching algorithm which determines the direction of moving vehicle in parallel section of road. It also employs a method for accuracy improvement. The results obtained from experimental test on real-time navigation show that the proposed systems works well and the accuracy increases.

• International Journal of Highway Engineering
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• v.14 no.4
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• pp.73-81
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• 2012

PURPOSES : The purpose of this study is to select the proper sealing method and to see the performance of the saw and seal method for concrete rehabilitation based on accelerated pavement testings and lab tests. METHODS : Two accelerated pavement testings were conducted. One is to select proper sealing method of the asphalt joints and the other is to see the performance of the saw and seal method. Lab tests were conducted to select proper sealing method and a test section was constructed to see the field performance. RESULTS : The result of the first accelerated pavement testing indicated that the adhesive preformed sealants showed good performance when asphalt layer was rutted and in terms preventing from water infiltration. The second acceleration test indicated that the saw and seal method using the adhesive preformed sealant showed much better performance than the control. In the lab test bitumen, rubber and epoxy showed good performance as the adhesive. CONCLUSIONS : Saw and Seal method using the adhesive preformed sealant would markedly reduce the joint damage on the asphalt overlay.

• Wind and Structures
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• v.11 no.4
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• pp.257-273
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• 2008

A number of passive aerodynamic drag reduction methods were applied separately and then in different combinations on an intercity bus model, through wind tunnel studies on a 1:20 scale model of a Mercedes Benz Tourismo 15 RHD intercity bus. Computational fluid dynamics (CFD) modelling was also conducted in parallel to assist with flow visualisation. The commercial CFD package $CFX^{TM}$ was used. It has been found that dramatic reductions in coefficient of drag ($C_D$) of up to 70% can be achieved on the model using tapered and rounded top and side leading edges, and a truncated rear boat-tail. The curved front section allows the airflow to adhere to the bus surfaces for the full length of the vehicle, while the boat-tails reduce the size of the low pressure region at the base of the bus and more importantly, additional pressure recovery occurs and the base pressures rise, reducing drag. It is found that the CFD results show remarkable agreement with experimental results, both in the magnitude of the force coefficients as well as in their trends. An analysis shows that such a reduction in aerodynamic drag could lead to a significant 28% reduction in fuel consumption for a typical bus on intercity or interstate operation. This could translate to a massive dollar savings as well as significant emissions reductions across a fleet. On road tests are recommended.

• Journal of Distribution Science
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• v.9 no.2
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• pp.25-30
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• 2011

Transport is animportant sector of government regulation. Every country has its own transport policy, but European countries are evolving a common transport policy, which has a long history. The establishment of a consistent common policy in the EU's transport sector is still underway. The key motivations of this policy are 1) to establish and implement a common transport policy, 2) to clarify the concept of sustainability in the transport sector, and 3) to integrate transport services into a common infrastructure. One of the policy's objectives is the progressive movement towards sustainable development in the transport section. The EU'stransport policy has recognised that intermodality is a very important competitive tool. The EU's policy thrustin intermodal transport can be catergorised into infrastructure, technology, and standards and rules. However, obstacles to success can be detected. Cases like that of TEN-T and Marco Polo illustrate European intermodal policies in practice. As regards sustainability in the transport sector, intermodality can be an alternative solution to the increasing imbalance between transport modes and congestion arising from increased road use. Sustainability has been emphasised by the EU, which aims to establish intermodality in its future alternative transport systems while fostering sustainable development in the transport sector. Therefore, intermodality can be defined as a general trend in the current transport market, drawing interest from public institutions and transport-related market players. The EU has thus made an effort to facilitate intermodality in its territory, materialised through various policy options. Therefore, looking into the EU's intermodal transport policies is worthwhile, as doing so can provide useful lessons for all concerned parties.

• Tunnel and Underground Space
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• v.14 no.5
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• pp.305-317
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• 2004

Due to the steep and narrow characteristic of domestic coal beds, the slant chute caving or sub-level caving method have been mainly adopted in Korea, whereas the long-wall mining has been widely used all around world. However, the slant chute caving or sub-level caving method have disadvantage of not giving much information on the scale and characteristic of abandoned mines. Hence, those information on the abandoned mines in Korea are not easily available. In this study, based on the characteristic investigation of the domestic mining methods, the geological survey and safety analysis were carried out for Donghae highway section 2. Finally, the optimum ground reinforcement methods for that site were selected.

• International Journal of Highway Engineering
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• v.17 no.2
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• pp.13-20
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• 2015

PURPOSES: This paper describes the expansion caused by the alkali-aggregate reaction (AAR) in concrete pavement currently in service. It also discusses the effects of joints installed to release the stress induced by the AAR expansion. METHODS: The expansion effect on concrete pavement was verified by a visual inspection and long-term measurement of the joint width of a cut-section. The behaviors of 16 newly installed joints were monitored as part of the investigation and long-term monitoring was carried out for three years after cutting. RESULTS: The behavior of a bridge was affected when AAR occurred in the connected pavement. The newly installed joints shrank in the longitudinal direction of the bridge after cutting. The width of the joints decreased over the six months after cutting. A large portion of the joint width (8.5cm) was found to have closed nine months after cutting. It had ultimately shrunk by about 92 percent when the final measurement was taken. CONCLUSIONS : The expansion of the pavement due to AAR was quantitatively described by visual inspection and the long-term monitoring of the newly cut joints. However, the width of the new joints decreased over the six to nine months after cutting. Additional research should be conducted to determine a means of controlling the expansion due to AAR in the pavement.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.1
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• pp.47-54
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• 2012

This study analyzed influence factors and the correlation among pollutants which affect occurrence of leaked pollution based on the long-term runoff flow and water quality investigation results to understand the characteristics of highway rainfall runoff pollution load. According to the result of correlation analysis on TSS (Total Suspended Solid) concentration, anteceded dry days, rainfall intensity, traffic volume and etc. as major influence factors of highway rainfall runoff pollution loads, the correlations were weak or scarce in most items. These results might be attributed that runoff pollutant concentration changes vary severely on changes of rainfall intensity and rainfall duration within rainfall and it is affected by disturbances of vehicles and street cleaning and etc. as characteristics of the highway. While Cu, Fe and Zn which are discharged with high concentrations out of heavy metals showed high correlation with particulate matter, organic matter(COD), nutrient(TN, TP), Ni and Pb showed relatively low correlation in a correlation evaluation by pollutant. Significant correlation with traffic volumes was not shown and TSS concentration even decreased in accordance with increase of the traffic volume. In the comparison with precedent studies, it was considered necessary additional analysis of the effects of rainfall section analysis, road type, disturbances of surface contaminants by vehicles, rainfall and climate conditions, surrounding terrains etc.

• Journal of Korean Society of Transportation
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• v.23 no.5 s.83
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• pp.57-64
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• 2005

Recently, several national construction projects such as Chunsung Mt. section of Kyungbu High Speed Rail or Sapae Tunnel of Seoul Outer Ring Road have been delayed or suspended due to the objections of residents or environmental organizations. Considering the development of democracy, increased public participation and interests on environmental issues in Korea, the generation of these social conflicts may be natural phenomenon. However, it is necessary to find measures to effectively implement major construction project and save costs related to social conflicts. In this paper, PI techniques in the United States are investigated and in comparison, the weakness and improvement plans for Korea's current public participation system have been suggested.