• Journal of the Korean Geotechnical Society
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• v.18 no.3
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• pp.87-94
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• 2002

Recently, there have been numerous attempts to expand the traditional temporary soil nailing system into a permanent wall. Two reasons for this include the soil nailed system's advantage of efficient and economic use of subgrade space and its ability to decrease the total construction cost. However, the systematic and logical design approach has not been proposed yet. The permanent soil nailing wall system, which utilizes precast concrete from soil nailing system, is already used in many countries, but the study of cast-in-place concrete lacing or rigid walls in bottom-up construction of traditional soil nailing walls is imperfect and insufficient. In this paper, various laboratory model tests have been carried out to investigate the influence of parameters, including stiffness of the rigid wall to the soil nailing structure with respect to failure mode, displacement patterns and tensile forces at the nail head in several levels of load. Then, the variation of earth pressure distribution on the soil nailing wall, built with a rigid front plate, is sought through different levels of surcharge load and tensile forces at the nail head.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.9 s.339
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• pp.85-96
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• 2005

A ' Virtual Private Network (YPN) over Internet' has the benefits of being cost-effective and flexible. However, given the increasing demands for high bandwidth Internet and for reliable services in a 'VPN over Intemet,' an IP/GMPLS over DWDM backbone network is regarded as a very favorable approach for the future 'Optical VPN (OVPN)' due to the benefits of transparency and high data rate. Nevertheless, OVPN still has survivability issues such that a temporary fault can lose a large amount of data in seconds, moreover unauthorized physical attack can also be made on purpose to eavesdrop the network through physical components. Also, logical attacks can manipulate or stop the operation of GMPLS control messages and menace the network survivability of OVPN. Thus, network survivability in OVPN (i.e. fault/attack tolerant recovery mechanism considering physical structure and optical components, and secured transmission of GMPLS control messages) is rising as a critical issue. In this Paper, we propose a new path establishment scheme under shared risk link group (SRLG) constraint for physical network survivability. And we also suggest a new logical survivability management mechanism by extending resource reservation protocol-traffic engineering extension (RSVP-TE+) and link management protocol (LMP). Finally, according to the results of our simulation, the proposed algorithms are revealed more effective in the view point of survivability.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.3
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• pp.93-100
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• 2021

Since the IB (Immersed Boundary) method, which can perform coupling analysis with objects and fluids having an impermeable boundary of arbitrary shape on a fixed grid system, has been developed, the IB method in various CFD models is increasing. The representative IB methods are the directing-forcing method and the ghost cell method. The directing-forcing type method numerically satisfies the boundary condition from the fluid force calculated at the boundary surface of the structure, and the ghost-cell type method is a computational method that satisfies the boundary condition through interpolation by placing a virtual cell inside the obstacle. These IB methods have a disadvantage in that the computational algorithm is complex. In this study, the simplified immersed boundary (SIB) method enables the analysis of temporary structures on a fixed grid system and is easy to expand to three proposed dimensions. The SIB method proposed in this study is based on a one-field model for immiscible two-phase fluid that assumes that the density function of each phase moves with the center of local mass. In addition, the volume-weighted average method using the density function of the solid was applied to handle moving solid structures, and the CIP method was applied to the advection calculation to prevent numerical diffusion. To examine the analysis performance of the proposed SIB method, a numerical simulation was performed on an object falling to the free water surface. The numerical analysis result reproduced the object falling to the free water surface well.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.4
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• pp.41-53
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• 2002

Role Based Access Control (RBAC), which is a method, using role as an access control, has been popular with users and it is recognized as an effective method to replace the Discretionary Access Control and the Mandatory Access Control However, the existing Role Based Access Control Models have only been limited to the bureaucracy organization in which a distinctive hierarchy system was used, incorporating a stable structure and a standardized work system. Only in some parts, some access control models have been used, which supports 'Team' concept, such as Team Based Access Control Model. However, it did not incorporate the characteristics of the adhocracy organization, which is similar to the company's task force team, whose characteristics are organic, temporary, no standardized operation procedures, and many frequent changes. In this study, we have discussed the characteristics of the adhocracy organization which is different from the existing bureaucracy organization, and we have also discussed the problems related to when the existing access control models are used as the access control model for the adhocracy organization due to its characteristics. In addition, based on the problems, we have suggested an improved role based access control model for the adhocracy organization, and have come up with the solutions when any problems occur in the access control system.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.228-240
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• 2022

A comprehensive safety management system will be required in accordance with the implementation of the Major Disaster Punishment Act for close-up safety management of construction sites. Safety management level evaluation management requires a comprehensive relationship between safety management under the Construction Technology Promotion Act and health and health management system under the Industrial Safety and Health Act. Purpose: Safety under the Serious Accidents Punishment Act. The ultimate goal is to study the comprehensive analysis and relationship of health management and to improve the safety evaluation level of health and health management. Methods: The feasibility of the questionnaire was confirmed through the second Delphi analysis of construction site experts and safety managers, and the regression coefficient and path analysis of potential variants in safety management, safety management, health management and safety inspection were confirmed. Result and Conclusion: In the structural model, the regression coefficient (89%) from safety management, health system, and safety management to safety inspection execution and lambda values of appropriate observation variables were confirmed. In the path analysis, the total effect (.809) was confirmed by mediating health hygiene in the relationship between health plan establishment adequacy and post-inspection management, and the path coefficient (.82) of temporary structure safety was confirmed.

• Health Policy and Management
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• v.33 no.3
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• pp.243-252
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• 2023

This paper aims to introduce Korea's total current health expenditure (CHE) and National Health Accounts of the year 2021 and their 2022 preliminary figures constructed on the basis of the System of Health Accounts 2011. As CHE includes expenditures for prevention, tracking, and treatment of coronavirus disease 2019 (COVID-19) and compensation for losses to medical institutions from 2020, the details are also introduced. Korea's total CHE in 2021 is 193.3 trillion won, which is 9.3% of gross domestic product (GDP). The preliminary figure in 2022, 209.0 trillion won, exceeded the 200 trillion won line for the first time, and its "ratio to GDP" of 9.7% is expected to exceed the average of Organisation for Economic Co-Operation and Development member countries for the first time. Korea's health expenditures, which were well controlled until the end of the 20th century, have increased at an alarming rate since the beginning of the 21st century, threatening the sustainability of national health insurance. The increase in health expenditure after 2020 is partly due to a temporary increase in response to COVID-19. However, when considering the structure of Korea's health insurance price hike, where the ratchet effect of increased medical expenses works particularly strongly, it is unlikely that the accelerating growth trend that has lasted for more than 20 years will stop easily. More aggressive policies to control medical expenses are required in the national health insurance which not only constitutes the main financing sources of the Korean health system but also has the most powerful policy means in effect for changes in the health care provision.

• Journal of the Korea Institute of Construction Safety
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• v.6 no.1
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• pp.19-26
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• 2024

In this study, we analyzed the status of safety management in industrial sites and fatal accident statistics to identify problems and suggest directions for increasing the utilization of convergence engineering. Current industrial site safety management is passive, formal, and unsystematic, and at the same time, the delivery of information on site safety management is very insufficient. In addition, domestic occupational safety and health education was not systematic and could not be considered effective as it was repeating past education forms. Recently, ICT technology has been introduced throughout the industry, and this study suggests several directions for the introduction of convergence safety engineering. Keke is the organization and operation of school curriculum in a convergent manner. In addition, we proposed a plan to apply VR content and experiential education so that safety management education can be conducted in a practical and realistic manner. Lastly, it was proposed to provide differentiated education by industry and type of work, taking into account the characteristics of various industrial sites. It is expected that the results of this study will be able to emphasize the need for convergence and integrated safety education for those involved in the field of domestic industrial safety management and education.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.4
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• pp.32-50
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• 2019

The present study examines the circumstances around the establishment of the Seonyu Eight Scenic Spots (仙遊八景) in Gogunsan Islands and the characteristics of the landscape of each viewing point. The study conclusions are as follows. First, since the scenic spots were first established in 1969, their content and sequences have been changed several times, and their names have also been changed to some extent. Until the 1970s, these scenic spots did not have official names for them and were often specified as 'Gogunsan Eight Scenic Spots', and excluded 'the Musan Twelve Peaks (巫山十二峰)'. In addition, viewing points of the eight scenic spots varied across periods. This suggests that, for the early form of Seonyu Eight Scenic Spots, the picturesque scenery of Gogunsan Islands, and Seonyudo Island in particular, was chosen, while eight scenic spots in its vicinity were regarded. Second, the Seonyu Eight Scenic Spots of the early 2000s, which has all eight scenic spots of now, follows the nomenclature of the traditional eight scenic spots by specifying the sequence number with a refined name in four syllables. Its first scenic spot was Mangju Waterfall (望主瀑布) and its eighth scenic spot was Seonyu Sunset (仙遊落照); currently, the first scenic spot is Seonyu Sunset and the second scenic spot is Mangju Waterfall. Such change in the sequence of viewing points resulted from differences in representative landscape resources between the periods. Third, the lack of structure and finesse due to continuous changes is directed related to the identity issue of the Seonyu Eight Scenic Spots. Above all, it is unclear by whom and when Seonyu Eight Scenic Spots was established, and there are clear traces of following the eight scenic spots in the neighboring areas such as Okgu (沃溝) and Impi (臨陂)'s Eight Scenic Spots. Moreover, it is evaluated to have an unrefined, incomplete structure due to the lack of clarity in the knowledge and information about viewing objects, when to view, and historical and cultural background. Fourth, the first scenic spot, Seonyu Sunset, has the image that dominates the entire Eight Scenic Spots. The temporary landscape, the sunset, became the best view because it was perceived as the entirety of the landscape created by the fusion of the beautiful natural elements of Seonyudo Island. Therefore, there is ample room for raising the value of other landscape resources of Gogunsan Islands by utilizing the existing perception of exploring the entire landscape of Seonyudo Island and Gogunsan Islands starting with Seonyu Sunset. This likely requires additional work to imbue each viewing point with identity and completion.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.5
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• pp.119-126
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• 2011

The standard unit manpower and material in landscape architectural construction was consist of a standard and universal work classification. However, these constructional methods have created a number of problems in utilizing and responding on a variety of recently-developed working methods such as new constructional skills and technologies. This research decided that presenting the amendments of work classification of a standard unit manpower and material in landscape architectural construction was very important, and investigated those work classifications which required these new amendments. First of all, assessment items were selected through the literature reviews and a preliminary survey. Then, these assessment items were surveyed to the total of 60 professional landscape architecture field. The results of this study were as follows; First, the utilization level of the a standard unit manpower and material in landscape architectural construction was highest in the area of work classification of planting unit manpower and material. Second, the work classifications that needed to be added were recognized as leveling the ground construction, landscape structure construction, paving construction, water facilities construction, and outdoor facilities construction. Third, in the field of the a standard unit manpower and material in landscape architectural construction, 66.7% of the respondents replied that some amendments were necessary, and those amendments needed work classifications were identified as work classification of planting unit manpower and material was gigantic plant, topiary tree, temporary planting, exchange dead tree, etc. In the area of digging out was gigantic plant and plastic tree were recognized. The survey respondents also answered that, in keeping and management work classifications some amendments in pruning waste were necessary, and in the fields of rubble masonry work classifications some improvements were required in rubble aperture planting unit manpower and material and sodding and herbaceous sowing was a realistic lawn size unit manpower and material was needed. Based on the results explained above, this study suggests that amendments for a standard unit manpower and material in landscape architectural construction are necessary, especially in the areas of planting size and quality of work classifications unit manpower and material and in the unit manpower and material that affects the quality of lands caping constructions.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.3
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• pp.199-212
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• 2007

If a type IP-2 transport package were to be subjected to a free drop test and a penetration test under the normal conditions of transport, it should prevent a loss or dispersal of the radioactive contents and a more than 20% increase in the maximum radiation level at any external surface of the package. In this paper, we suggested the analytic method to evaluate the structural safety of a type IP-2 transport package using a thick steel plate for a structure part and a bolt for tying a bolt. Using an analysis a loss or dispersal of the radioactive contents and a loss of shielding integrity were confirmed for two kinds of type IP-2 transport packages to transport radioactive waste drums from a waste facility to a temporary storage site in a nuclear power plant. Under the free drop condition the maximum average stress at the bolts and the maximum opening displacement of a lid were compared with the tensile stress of a bolt and the steps in a lid, which were made to avoid a streaming radiation in the shielding path, to evaluate a loss or dispersal of radioactive waste contents. Also a loss of shielding integrity was evaluated using the maximum decrease in a shielding thickness. To verify the impact dynamic analysis for free drop test condition and evaluate experimentally the safety of two kinds of type IP-2 transport packages, free drop tests were conducted with various drop directions. For the tests we examined the failure of bolts and the deformation of flange to evaluate a loss or dispersal of radioactive material and measured the shielding thickness using a ultrasonic thickness gauge to assess a loss of shielding integrity. The strains and accelerations acquired from tests were compared with those by analyses to verify the impact dynamic analysis. The analytic results were larger than the those of test so that the analysis showed the conservative results. Finally, we evaluated the safety of the type IP-2 transport package under the stacking test condition using a finite element analysis. Under the stacking test condition, the maximum Tresca stress of the shielding material was 1/3 of the yielding stress. Two kinds of a type IP-2 transport package were safe for the free drop test condition and the stacking test condition.