• Journal of Korea Multimedia Society
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• v.20 no.4
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• pp.649-659
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• 2017

Typically, a smart car is equipped with access to the Internet and a wireless local area network. Moreover, a smart car is equipped with a global positioning system (GPS) based navigation system that presents a map to a user for recommending the shortest path to a desired destination. This paper presents the design and implementation of a real-time shortest path search system for directed and dynamic roads. Herein, we attempt to simulate real-world road environments, while considering changes in the ratio of directed roads and in road conditions, such as traffic accidents and congestions. Further, we analyze the effect of the ratio of directed roads and road conditions on the communication cost between the server and vehicles and the arrival times of vehicles. In this study, we compare and analyze distance-based shortest path algorithms and driving time-based shortest path algorithms while varying the number of vehicles to search for the shortest path, road conditions, and ratio of directed roads.

• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.408-421
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• 2014

This study was carried out to investigate flora and vegetation in cutting slope along a construction age sequence (2007, 2009, 2010, 2011, 2012) of forest roads in Yongchiri, Younghyunmyon, Sacheonshi, Geyongsangnamdo. Mean slopes of the cutting and banking slopes of forest roads constructed were ranged from $42^{\circ}$ to $54^{\circ}$. Soil texture in the cutting and banking sides of forest roads constructed in 2012 was loam, while sandy loam in the cutting and banking slopes of forest roads constructed between 2007 and 2011. Vegetation cover percentage was higher in the banking slopes (66%) than the cutting slopes (49%) of forest roads. Total flora were higher in the banking slopes (50 species) than the cutting slopes (46 species) of forest roads. Species diversity was generally higher in the banking slopes than in the cutting slopes in all forest roads. In addition, the species diversity index was the highest in the cutting slopes (1.4015) of forest roads constructed in 2011, while the highest in the banking slopes (1.5603) of forest roads constructed in 2012. The results indicate that evenness index in the cutting and banking slopes of recent construction roads was high compared with old construction roads because of the distribution of simple plant species.

• International Journal of Highway Engineering
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• v.19 no.6
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• pp.155-164
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• 2017

PURPOSES : Owing to the growth of income and socio-economic levels, demands from road users have diversified. Accordingly, new road policies are being actively sought. The metropolitan city government of Busan has been focused on constructing and expanding roads to accommodate the increasing traffic demand. Given the increase in functional characteristics, we need to re-evaluate the hierarchy and function of roads, and specifically remodel the road planning and operations that fit into their functions. METHODS : First, this study focuses on introducing the minimum condition required to redefine the hierarchy of the roads. Second, the authors propose a new model that identifies the impact level of road hierarchy adopting discriminated analysis technique. RESULTS : Authors suggest that we redefine the hierarchy of roads in the central business distinct in Busan, and specifically the arterial roads in Busan, namely, Joonang-daero and Gaya-ro. These roads need to be reequipped with cross walks, a lower speed limit, and exclusive bus lanes to improve their accessibility. CONCLUSIONS : The authors found that the sub-arterial and collector roads have been subjected to excessive loads, owing to inappropriate functions being assigned to the main arterial road. Moreover, given that through traffic is concentrated on the sub-arterial and collector roads, over-speeding and other safety issues are consequently created.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.367-372
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• 2004

Highway have to be constructed under thorough investigation about function, economy, safety of the traffic and environment, because they are needing huge budget for construction and management as important facilities of the social overhead capital in the national economics. Initially the construction of roads becomes effective the plan, the design, construction phase. The design is foundation of accomplishment of the roads operation, the results of the design operation come to much effect a nation when using roads. Especially ancient design methods were not expected for visual effects as attaching weight to 2-dimensional drawing from flat. Therefore, it is difficult to recognize troubles happened during the work operation besides, many troubles are solved by modification of drawings as situations. For solving of those of the problems, it is emphasize on visual effect through introduction of 3-dimensional design from the initial phase. In case of national conditions, limited national land has caused increasing weight for construction of the roads through cities as the urban centered development. thereupon, citizens are increasing concern about the right of the light and the environmental effect, road designs and construction of the structures under agreement with local residents cause to make troubles. The analysis of 3-dimensional design is necessary as intermediation for decision making. In this study, Virtual reality techniques in 3-dimensional roads design are expected to visual effect on the publishing Internet Web, find problems in first phase and make decision between users and people having civil appeal.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.5135-5142
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• 2011

A flexible mechanism is proposed in this paper to improve the dynamic response performance of a traffic flow control system in an urban area. The roads, vehicles, and traffic control systems are all modeled as intelligent systems, wherein a wireless communication network is used as the medium of communication between the vehicles and the roads. The necessary sensor networks are installed in the roads and on the roadside upon which reinforcement learning is adopted as the core algorithm for this mechanism. A traffic policy can be planned online according to the updated situations on the roads, based on all the information from the vehicles and the roads. This improves the flexibility of traffic flow and offers a much more efficient use of the roads over a traditional traffic control system. The optimum intersection signals can be learned automatically online. An intersection control system is studied as an example of the mechanism using Q-learning based algorithm, and simulation results showed that the proposed mechanism can improve the traffic efficiency and the waiting time at the signal light by more than 30% in various conditions compare to the traditional signaling system.

• Korean Journal of Agricultural Science
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• v.44 no.4
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• pp.504-512
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• 2017

Forest roads are essential for forest resource management. This study investigated and compared forest road and road policy data in Korea and the United States to improve future forest road policies in Korea. As compared to the United States (9.5 m/ha), Korea has much lower forest road density (3.19 m/ha) and has been actively constructing new forest roads. The Korea Forest Service leads forest road policy in Korea by providing subsidies for new road construction in non-national forests. The budget for forest roads accounted for 9.1% of the total Korea Forest Service budget in 2010 - 2015 and 73.5% of it was used for new road construction. Korean forest road policies have been distinctively changed over the past decades; e.g., an increase in forest road mileage in the 1990s, an increase in forest road standards in the 2000s, and an increase in the mileage of higher standard roads in the 2010s. In comparison to Korea, the United States has focused on road maintenance and road decommissioning since 2001. The budget for forest roads accounted for 2.9% of the total USDA Forest Service budget in 2011 - 2016 and 82.2% of it was used for operations and maintenance. Our study results suggest that forest road policies in Korea should start focusing on road maintenance and decommissioning, if needed.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.1
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• pp.63-72
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• 2005

Chirisan National Park, the first and largest one out of 20 national parks in Korea, is divided into five zones. They are composed of nature preservation zone, natural environment zone, natural residential zone, concentrated residential zone, and collective facility zone. However, the park is not a continuous habitat: roads, trails, local residences, and various facilities created the habitat mosaics severely fragmented. We investigated the fragmentation pattern of the park due to roads and mountain trails using GIS. Based on perimeter length, area, and the ratio of perimeter to area of each patch, we obtained landscape analysis indices which reflect the regularity of the patch shape. The 1 m-wide hiking trails divided the park into 491 fragments. The legal trails with 1.5 m - 3 m width which have been heavily used by hikers generate 58 fragments. Even the nature preservation zone, corresponding to a core zone comprising 31.8% of the park area, was divided into 37 fragments because of the roads and mountain trails. With the different widths of buffer applied, the core sizes of the fragments were reduced. When the 60 m buffer was applied, the patch interior areas ranged from 0.0001 to 47.77 $km^2$ with a mean of 7.08 $km^2$. The landscape shape indices were far greater than 1 for most of the cases with a maximum value of 25. These results clearly indicate that Chirisan National Park is not a continuous habitat, but mosaics of small, irregularly shaped habitat fragments. It is necessary to take the size and shape of the fragmented habitats into consideration when nature conservation is planned, especially for large wildlife such as brown bears.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.2
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• pp.34-43
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• 2007

To investigate the restoration procedure on soil physical properties and vegetation at the surface of strip road affected by timber harvesting operation. This study was carried out at strip roads constructed between 1989 and 1994 in Mt. Baekun, Kwangyang, Chollanam-Do. Soil hardness of the surface layer was improved with change of time after strip road construction, but that of 7.6~15 cm depth from the surface was not improved. According to linear regression analysis, it was estimated 16.6 years in 0~7.5 cm and 16.9 years in 7.6~15 cm soil depth to be restored to natural forest lands. The amount of surface soil erosion was 0.045$m^3$/km/yr on strip roads constructed in 1989 and 1990, and road constructed in 1994 showed the highest value (4.5$m^3$/km/yr). Vegetation coverage rates of road surface were 96.7% in strip roads constructed in 1990. Those of cutslope and fillslope were highest in roads constructed in 1990. The results indicated that strip roads were restored with change of time after road construction.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.917-918
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• 2013

Navigation or Portal sites is providing real-time information of roads according to heavy rain in guide services for finding a path recently. Especially "e-traffic alerts" is providing traffic information according to the presence of road flooding and accidents. This research is goal to provide drivers to real-time status information of roads which have the connected its information to support the real-time rainfall information of meteorological office and portal sites. We suggest the evaluation method of risk roads combined the real-time rainfall information and portal information.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.4
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• pp.537-548
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• 2022

It is important to design the pavement thickness considering heavy-duty traffic loads, which can cause excessive stress and strain in the pavement. Port-rear roads and industrial roads have many problems due to early stress in pavement because these have a higher ratio of heavy loads than general roads such as national roads and expressways. Internationally, composite pavement has been widely applied in pavement designs in heavy-duty areas. Composite pavement is established as an economic pavement type that can increase the design life by nearly double compared to that of existing pavement while also decreasing maintenance and user costs. This study suggests a thickness design method for composite pavement using roller-compacted concrete as a base material to ensure long-term serviceability in heavy-duty areas such as port-rear roads and industrial roads. A three-dimensional finite element analysis was conducted to investigate the mechanical behavior and the long-term pavement performance ultimately to suggest a thickness design method that considers changes in the material properties of the roller-compacted concrete (RCC) base layer. In addition, this study presents a user-friendly catalog design method for RCC-base composite pavement considering the concept of linear damage accumulation for each container trailer depending on the season.