• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.2
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• pp.203-210
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• 2003

A simulation study was carried to analyze the vehicle fuel consumption on component basis. Experiments was also carried out to identify the simulation results, under FTP-75 Hot Phase driving conditions. and arbitrary driving conditions. A good quantitative agreement was obtained. Based on the simulation, fuel energy was used in pumping loss(3.7%), electric power generation(0.7%), engine friction(12.7%), engine inertia(0.7%), torque converter loss(4.6%), drivetrain friction(0.6%), road-load(9.2%), and vehicle inertia(13.4%) under FTP-75 Hot Phase driving conditions. Using simulation program, the effects of capacity factor and idle speed on fuel consumption were estimated. A increment of capacity factor of torque converter resulted in fuel consumption improvement under FTP-75 Hot Phase driving conditions. Effect of a decrement of idle speed on fuel consumption was negligible under the identical driving conditions.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.475-478
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• 2005

This study was performed to evaluate about load bearing capacity of continuos IPC Girder Bridge under and after Construction. This is Ichi-1 Bridge that is 2-40m span continuous bridge on a extension road through the Ichun and the Naesa. The result of static loading test to use a 25ton truck after construction, deflection ratio is 0.64 that is $35\%$ and average of response ratio is 0.48$\~$0.89 that is less than theoretical value. The result of dynamic loading test, the number of proper vibrations is 3.06Hz that is like theoretical value 3.61Hz, the modulus of impact is 0.235 that is bigger than specification 0.19. the load bearing capacity is minimum DB-40 that is so big value. In the result, continuos IPC Girder Bridge is safe in short period. we will evaluate long period behavior of continuos IPC Girder Bridge.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.782-791
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• 2009

This study was carried out the laboratory tests and field plate load test in order to evaluate the reinforcement effect of geocell for road construction. The geocell-reinforced subgrade shows the increment of cohesion and friction angle with comprison of non-reinforced subgrade. In addition, the field plate load test was performed on the geocell-reinforced subgrade to estimate the bearing capacity of soil. The direct shear test was conducted with utilizing a large-scale shear box to evaluate the internal soil friction angle with geocell reinforcement. The number of cells in the geocell system is varied to investigate the effect of soil reinforcement. The theoretical bearing capacity of subgrade soil with and without geocell reinforcement was estimated by using the soil internal friction angle. The field plate load tests were also conducted to estimate the bearing capacity with geocell reinforcement. It is found out that the bearing capacity of geocell-reinforced subgrade gives 2 times higher value than that of unreinforced subgrade soil. In the future, the reinforcement effect of the geocell rigidity and load-balancing effect of the geocells should be evaluated.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.545-552
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• 2017

Ground subsidence can result in the formation of sinkholes, potholes, settlement of structures, and road subsidence. Road subsidence is described as the sudden collapse of the road surface into subsurface cavities caused by the loss of bearing capacity in the ground, such as the dissolution of limestone by fluid flow in the surface causing the formation of voids leading to subsidence at the surface. Road subsidence occurs about 665 times annually, and this incidence has been increasing until 2013. Damaged underground facilities, management negligence, and lowering of the ground water table have been the causes of road subsidence in Seoul. Seoul metropolitan government announced special management counter plans to relieve the anxieties and make the roads safe for passing. Construction sites, such as excavation works, need to be managed properly because they have strong potential to induce road subsidence. The aim of this study was to identify the main causes of road subsidence and suggest management plans. First, life cycle cost analysis revealed the daytime construction to be more appropriate than nighttime. In addition, by analyzing the limitations of using sand as a backfill material, it is proposed to use a flowable backfill material instead of sand. Finally, to reduce the blind spots, which is a problem in surveying the road pavement conditions of local governments, the road to be managed is divided into several zones, and a specialized agency is selected for each zone and a method of surveying the blind spots through collaboration is suggested.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.3
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• pp.21-28
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• 2012

The main objective of this study is to reveal the basic information for structuring the subsequent information monitoring and early warning system and configuring the sustainable programme management of Donggung and wolji, Gyeongju which was much utilized as historic garden with the physical carrying capacity and the psychological carrying capacity according to on-spot observation and survey. The physical carrying capacity can be calculated with landscape node spatial capacity, road spatial capacity and other spatial capacity and the psychological carrying capacity can be calculated with vision, hearing, touch, action feeling and satisfaction. The number of actual tourists was lower than the carrying capacity in daytime, but it was about twice as great as that in the night. And because the tourists were mainly tour groups, the time of environment damaged was short and fixed. The management improvement program was brought forward centre around the results.

• Journal of Environmental Policy
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• v.11 no.3
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• pp.49-65
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• 2012

Road traffic noise is closely related to road traffic environment, including traffic volumes by type and travel speed. In this study, we stated some issues and analyzed the relationships between road traffic noise and traffic flow characteristics. First, in attempt to find the answer to the question "When does the loudest traffic noise occur?" we reviewed the issue in the terms of traffic flow. As a result of analyzing level of service through Korea Highway Traffic Noise model, the actual maximum noise occurred in level of service D rather than level of service E, on the capacity state. It shows that maximum noise would be most likely to occur right before and after the peak hours. Second, this paper was looking for the method of a more easy and accurate traffic speed estimation to predict traffic noise. This paper proposed sketch planning techniques of speed-volume curve by level of service on Korea Highway Capacity Manual. As a result of trend line modeling, it was judged that quadratic form is a suitable function, and coefficient of determination ($R^2$) was higher than 0.96, respectively.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.2
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• pp.65-71
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• 2016

The new concept of agricultural water supply potential, which is mean annual turnover rate times unit storage capacity, was introduced for agricultural reservoirs. We investigated characteristics of mean annual turnover rate and unit storage capacity for agricultural reservoirs with storage capacity of over $1million\;m^3$. The curve of agricultural water supply potential represents change in mean annul turnover rate according to change in unit storage capacity. The mean annual turnover rate and unit storage capacity in the reservoirs with high minimum storage ratio are significantly higher than those in the reservoirs with low minimum storage ratio. Most of unstable water supply reservoirs showed low mean annual turnover rate or low unit storage capacity, indicating that mean annual turnover rate may be an index of stability degree for agricultural water use. The reservoirs with mean annual turnover rate of over 2 and unit storage capacity of over 0.8 m may be estimated as the stable water supply zone for 10 frequency dry year. The reservoirs with high agricultural water supply potential can belong to the wide range of stable water supply zone. The results suggest that relation between mean annual turnover rate and unit storage capacity may be used in evaluating stability degree for agricultural water supply in the reservoirs.

• Journal of the Korean GEO-environmental Society
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• v.15 no.2
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• pp.67-74
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• 2014

Recently, the number of road construction is increasing by industrial development. According to this industrial tendency, the number of traffic accidents are consistently increasing due to increasing number of vehicle on the road. This is mainly because traffic accidents are occurred by various parameter such as negligence of driver, vehicle defects, state of unstable road, natural environment etc. Lane department of vehicles from guardrail is occurring frequently. This type of accident is caused by vehicle performance improvement and shape of vehicle, weak guardrail installation and maintenance. Guardrail has the purpose on prevention such as prevention of traffic accident and prevention of deviating out of road, minimizing damage of driver and vehicle by collision as well as entry into the road through guardrail. Stability evaluation test of guardrail verifies the behavior of guardrail through the crash of truck. At this time, the crash condition has 100 km/h of velocity and $15^{\circ}$ of impact angle. In the case of ground condition, filling slope condition has relatively high bearing capacity of infinite ground towards the test. Guardrail is generally installed on road of shoulder in fill slope in korea. It is possible for stability problem to deteriorate ground bearing capacity in Guardrail in fill slope. The existed study towards stability of guardrail has been carried out in the infinite ground. However, the study on the behavior of fill slope with guardrail is not performed by vehicle collision. Therefore, In this study, the numerical analysis using LS-DYNA was executed for verification on behavior of fill slope with guardrail through vehicle collision. This numerical analysis was carried out with change of embedded depth on installed guardrail post in shoulder of fill slope by vehicle collision and 8 tonf truck crash providing at NCAN (National Crash Analysis Center). As the result, displacement and stress on fill slope are decreased in accordance with the increase of embedded depth of guardrail post. Ground bearing capacity is deteriorated at depth of 450 mm form shoulder of road on fill slope.

• Ecology and Resilient Infrastructure
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• v.8 no.4
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• pp.223-232
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• 2021

In general, stormwater flows to the road surface, especially in urban areas, and it is discharged through the drainage grate inlets on roads. The appropriate evaluation of the road drainage capacity is essential not only in the design of roads and inlets but also in the design of sewer systems. However, the method of road surface flow analysis that reflects the topographical and hydraulic conditions might not be fully developed. Therefore, the enhanced method of road surface flow analysis should be presented by investigating the existing analysis method such as the flow analysis module (uniform; varied) and the flow travel time (critical; fixed). In this study, the algorithm based on varied and uniform flow analysis was developed to analyze the flow pattern of road surface. The numerical analysis applied the uniform and varied flow analysis module and travel time as parameters were conducted to estimate the characteristics of rainfall-runoff in various road conditions using the developed algorithm. The width of the road (two-lane (6 m)) and the slope of the road (longitudinal slope of road 1 - 10%, transverse slope of road 2%, and transverse slope of gutter 2 - 10%) was considered. In addition, the flow of the road surface is collected from the gutter along the road slope and drained through the gutter in the downstream part, and the width of the gutter was selected to be 0.5 m. The simulation results were revealed that the runoff characteristics were affected by the road slope conditions, and it was found that the varied flow analysis module adequately reflected the gutter flow which is changed along the downstream caused by collecting of road surface flow at the gutter. The varied flow analysis module simulated 11.80% longer flow travel time on average (max. 23.66%) and 4.73% larger total road surface discharge on average (max. 9.50%) than the uniform flow analysis module. In order to accurately estimate the amount of runoff from the road, it was appropriate to perform flow analysis by applying the critical duration and the varied flow analysis module. The developed algorithm was expected to be able to be used in the design of road drainage because it was accurately simulated the runoff characteristics on the road surface.

• Journal of Korean Society of Transportation
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• v.9 no.2
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• pp.135-144
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• 1991

In recent years parking problems have been rapidly highlighted. Particularly on-street parking has become a very serious problem so an immediate action needs to be taken to resolve this problem. On-steet parking is attributable not only to insufficient capacity of parking lots but also to the facts that must of the parking lots are far away from the destinations to which drivers intend to go and that their locations are unclear. The effect of on-street parking is so great as to cause road traffic problems such as traffic jam and danger to road safety as well as to lead to obstructing business activities resulting in a decline of commercial areas. Therefore on-street parking is an important problem for a city as a whole. In this paper I have investigated a parking lot information and guiding system as one of the techniques to resolve the on-street parking problem and have clarified the effect of introducing this system and necessary conditions for implementing an optimum information and guiding system. Moreover I have pointed out the problems to be encountered in imp-lementing such system in areas not equipped with infrastructures taking into account the road conditions in these areas and have stated that it would be necessary to develop a new idea of information and guiding system in order to overcome these problems. I have suggested a Shot Gun Method as a proposal and have discussed extensibility of this method in the future.