• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.37 no.5
• /
• pp.787-799
• /
• 2017

Although the long-term leakage between the box culvert and the soil contact surface is one of the main causes of the failure in the embankment of the reservoir, there is a little studies on this matter. If a leakage occurs by the structure such as the buried box culvert of reservoir embankment is partially damaged, it is difficult to observe and there is a possibility of damage caused by piping. For these reasons, more research is necessary. In this study, the embankment type of the reservoir is divided into the core type and the homogeneous type when the damaged box culvert passing through the embankment of the reservoir is leaked due to the differential behavior of materials like differential settlement. In view of the condition, the seepage analysis of 2D was performed according to the water level change. The result of the study shows that the possibility of piping increases at the upper part rather than the bottom part of the box culvert when the leakage occurs to the box culvert passing through the embankment of the reservoir. Particularly, it is considered that the presence of the core helps to maintain the seepage stability of the embankment in case where the leakage occurs at the downstream side of the embankment. Also, if there is a drastic decrease on the internal pore water pressure in the embankment of reservoir, it is necessary to consider the possibility of piping.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.19 no.2
• /
• pp.231-248
• /
• 2017

Government plans to construct a double-deck tunnel under a portion of Gyeongbu Expressway that will solve traffic problems and could also be used as a flood storage facility. Divergence tunnels connect the main tunnel to the urban areas and their construction effects on adjacent structures at shallow depth need to be analyzed. This study primarily includes the numerical analysis of construction effects of divergence tunnels on utility tunnels. The utility tunnel was analyzed for three cases of volume loss applied to the divergence tunnel and two cases of the angle between main tunnel and divergence tunnel ($36^{\circ}$ and $45^{\circ}$). The results show that the more the volume loss was applied and the shorter the distance was between utility tunnel and divergence tunnel, the more the utility tunnel was affected in terms of induced displacements, angular displacement and stability. The worst scenario was found out to be the one where the angle between main tunnel and divergence tunnel was $36^{\circ}$ and the distance between divergence tunnel and utility tunnel was 10 m, resulting in the largest displacement and differential settlement at the bottom of the utility tunnel. A relationship between the angular displacement and the distance to diameter ratio was also established.

• 재활복지
• /
• v.17 no.4
• /
• pp.1-26
• /
• 2013

As the social development progress, social welfare policy for people with disabilities also advance to meet rights of people with disabilities. The personal assistance service(PAS) is the primary service system for persons with disabilities based on guaranteeing the self-determination. The purpose of this study was to compare the personal assistance service system between Japan and Korea to propose improvement plan for Korean system. The comparison of two countries was based on current situation analysis of PAS. The analysis on eligibility criteria, information referral, amount and type of services and service provider, appealing process and service fee deductible etc. The result showed that PAS in Korea is served according to administration convenience than personal need based. Korean PAS policies are limited to particular service amount and type of needed services to satisfy personal PAS need. Whereas, Japan PAS system is served on the philosophy of independent living paradigm and therefore, PAS is provided on personal service needs. The service emphasis is on self-determination and rights on service selection for persons with disabilities. The recommendation for improvement of PAS in Korea are as followed. First, PAS should served under independent living paradigm. Paradigm based service is important because it effects the main theme of PAS; the self determination and rights of service selection. Second, reconstruction of PAS system is needed. As it showed on analysis, eligibility criteria, information referral, amount and type of services and service provider, appealing process and service fee deductible need to be supplemented. Last, to better serve PAS, case management method should be apply. Case management would contribute to settlement of PAS system in Korea. Thru case management, participation opportunities of people with disabilities must be provided during the selection of service quantity and type of PAS.

• Journal of Forest and Environmental Science
• /
• v.34 no.6
• /
• pp.461-471
• /
• 2018

In this study, the deforestation and forest degradation areas have been obtained in Myanmar using a land cover lamp (LCM) and a tree cover map (TCM) to get the $CO_2$ potential reduction and the strength of occurrence was evaluated by using the geostatistical technique. By applying a multiple criteria decision-making method to the regions having high strength of occurrence for the $CO_2$ potential reduction for the deforestation and forest degradation areas, the priority was selected for candidate lands for REDD+ project. The areas of deforestation and forest degradation were 609,690ha and 43,515ha each from 2010 to 2015. By township, Mong Kung had the highest among the area of deforestation with 3,069ha while Thlangtlang had the highest in the area of forest degradation with 9,213 ha. The number of $CO_2$ potential reduction hotspot areas among the deforestation areas was 15, taking up the $CO_2$ potential reduction of 192,000 ton in average, which is 6 times higher than that of all target areas. Especially, the township of Hsipaw inside the Shan region had a $CO_2$ potential reduction of about 772,000 tons, the largest reduction potential among the hotpot areas. There were many $CO_2$ potential reduction hot spot areas among the forest degradation area in the eastern part of the target region and has the $CO_2$ potential reduction of 1,164,000 tons, which was 27 times higher than that of the total area. AHP importance analysis showed that the topographic characteristic was 0.41 (0.40 for height from surface, 0.29 for the slope and 0.31 for the distance from water area) while the geographical characteristic was 0.59 (0.56 for the distance from road, 0.56 for the distance from settlement area and 0.19 for the distance from Capital). Yawunghwe, Kalaw, and Hsi Hseng were selected as the preferred locations for the REDD+ candidate region for the deforestation area while Einme, Tiddim, and Falam were selected as the preferred locations for the forest degradation area.

• Journal of the Society of Disaster Information
• /
• v.17 no.3
• /
• pp.454-464
• /
• 2021

Purpose: There is a need to construct an evacuation passageway for the 2-Arch tunnel, which has been constructed and is in operation. Therefore, it aims to analyze tunnel and center wall behaviour and stability due to excavation of the center wall. Method: We describe the theoretical background of 2-Arch tunnel and evacuation passageway, and focused on analyzing the behaviour of tunnel and wall using 3-dimensional finite element analysis. Parametric analysis according to rock rating was performed with various ground conditions, and the displacement and stress of the center wall were intensively analyzed. Result: With the center wall excavation, the largest amount of settlement was shown in the center of the opening, and the stress was greatest during the first excavation. In addition, it was shown that stress concentration occurred at the top of both openings, and stability reviews considering the concept of allowable stress showed that it exceeded the allowable stress. Conclusion: Although the displacement of the tunnel has secured stability within the allowable standard, the generated stress is found to exceed the allowable standard, so it is necessary to prevent sudden stress release by applying appropriate reinforcement methods during construction.

• Journal of Internet Computing and Services
• /
• v.22 no.4
• /
• pp.123-134
• /
• 2021

This paper suggests that the Internet is not free through analysis of U.S. Internet history and lawsuits related to the Charter merger in 2016. Generally speaking, the players in internet connectivity market agree to Non-Disclosure Agreement, when connecting their facilities and networks each other. So, I adopted the case study & analysis as research methodologies due to limitation of collecting the transaction data between them. The former finds that Internet access has never been free in U.S Internet history. As we know, some including Content Providers(CPs) argue that the Internet is a free network and there are many cases to use the internet for free, so they came to conclusion that ISPs have no right to charge the users like CPs. This study refutes these arguments in two ways. One is that using the internet has never been free. From ARPANET, known as the beginning of the U.S. Internet, to the commercialization of backbone, no Internet has been considered or implemented for free since the early Internet network was devised. Also, the U.S government was paying subsidies or institutions were paying fees to secure network operations for the NSFNET backbone. the other is that "free peering" refers to barter transactions between ISPs, not to free access to counterpart internet networks. Second, this study analyze the FCC' executive order of conditioned merger approval and the court's related ruling and verify that using the internet is not free. According to the analysis, this study finds that it's real situation to make paid settlements between ISP-CPs (including OTTs) in the US Internet market at the moment. This study concludes that the Internet has never been free in terms of its technical characteristics, network structure, network operation, and system. Also it proposes how to improve the domestic settlement system between ISPs-CPs in terms of policy and regulation.

• Journal of the Korean GEO-environmental Society
• /
• v.12 no.10
• /
• pp.39-49
• /
• 2011

Recently PBD method, one of acceleration of consolidation methods is used in the soft ground to shorten consolidation time for fast settlement during construction. It is economical and easy to work. Discharge capacity of PBD is sensitive in proportion to thickness of soft ground layer, and drainage of PBD declines due to disturbance effect in surrounding ground by mandrel used for vertical drainage setting and setting machines and type. Also, deviation of discharge capacity is large according to ground condition, construction condition and soil properties. In addition, when embankment loading is not conducted instantly after PBD setting due to rain or lack of embankment material supply, it causes leaving period problems. But cause and analysis of those problems for discharge capacity is lack. So, in this test, ground improvement and discharge capacity is investigated by implementing composite discharge capacity test for analysis of an effect factor of PBD discharge capacity with leaving period. After fixing the vertical drain on a cylindrical cylinder, put churned sample into the cylinder. Then leave 0day, 30day, 60day and 90day. And then, load following the loading step of 30, 70 and 120kPa using a pressure device. As a result, the longer leaving period, discharge capacity is reduced. It is caused by a decrease of discharge area caused by creep transformation moisture absorption of PBD filter after long leaving period.

• Journal of Korean Society of Forest Science
• /
• v.100 no.4
• /
• pp.639-649
• /
• 2011

The purpose of this study aimed to analyze factors on motives to tree burial and choice conditions to tree burial site in order to suggest policy direction for the desirable settlement of tree burial. For those purpose, this study performed questionnaire, targeting 522 visitors of funeral hall all around Korea. As the result, the factors of motives to tree burial were extracted as follows: funeral ceremony progressed along with trees, simplicity, memorial site's easy insurance, environmental friendliness and consideration toward descendants. The factors on choice conditions to tree burial sites were extracted as follows: beauty of natural scenery, emotional mood as a memorial site, convenience, stability and economic feasibility. Based on the results of factor analysis, this study suggested policies related to motives to tree burial as follows: develop various types of tree burial sites, develop a funeral ceremony suitable for tree burial, come into wide use of tree burial as a social welfare service, develop tree burial methods capable of many burials, and improve professionalism to manage tree burial system. In addition, this study proposed related choice conditions to tree burial sites as follows: establish natural forest scenery, convert existing graveyards into tree burial sites, select easily accessible places for tree burial sites, form tree burial sites as places for both rest and memory, and reduce using fee of tree burial site.

• Journal of Korea Port Economic Association
• /
• v.37 no.3
• /
• pp.19-34
• /
• 2021

Yeosu Gwangyang Port, along with Busan Port, Incheon Port, Ulsan Port, and Pyeongtaek Dangjin Port, serves as Korea's top five ports for trade on the southern coast. It is the second largest port in Korea after Busan Port, and the largest port in terms of import and export volume. Yeosu Chemical Industrial Complex, the world's largest chemical industrial complex, has continued to grow rapidly, but recently, the increase in volume has been decreasing. Therefore, this study sought to find major development strategies for the development of Yeosu Gwangyang Port and to derive the priorities of the strategies. To this end, the development strategy of Yeosu Gwangyang Port was divided into three major categories: operation revitalization, infrastructure construction, and policy support using the AHP analysis technique and analyzed again in two aspects: short, medium, and long term. As a result of the analysis, 'integrated operation of container docks and strengthening competitiveness' were considered the most important in short- and medium-term policies. It is believed that it will be necessary to integrate container operators, establish routes in preparation for entry of super-large ships, and install large cranes. In the long-term policy, the most important thing was to foster high value-added industries based on local industries. It is believed that strategies are needed to attract companies from outside regions through the settlement support system. The results of this study are expected to be used to establish development strategies for Yeosu Gwangyang Port and to establish investment priorities.

• Journal of Digital Convergence
• /
• v.20 no.2
• /
• pp.1-8
• /
• 2022

Although the OTT industry is an area that needs urgent policy response as a priority area under the new industry regulatory reform master plan, various issues are occurring due to the lack of related institutional infrastructure. Therefore, this study aims to analyze the policy conflict structure in which regulatory obstacles and delays occur by listening to the opinions of major stakeholders and using the Q methodology to identify the regulatory innovation demand of the OTT industry. The analysis results are as follows. The analysis results are as follows. First, in the implementation of OTT-related policies, it is necessary to improve the standard system for the method of settlement of copyright fees. Second, it is required to improve the support method that can reduce the burden of OTT operators' fund. Third, it is necessary to supplement the system by changing the regulatory application method for potential regulatory issues related to zero-rating. This study can be utilized in the process of introducing a system in which various stakeholders are connected and developed in a complex manner in the process of regulatory innovation in new industries and services.