• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.6 s.107
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• pp.23-35
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• 2005

Korean goral (Nemorhaedus caudatus raddeanus) is an endangered species in Korea, and the rugged terrain of the Sorksan National Park $(373km^2)$ is a critical habitat for the species. Since the goral population is threatened by habitat fragmentation, it is essential to establish a reserve for the isolated goral population. The objective of this study was to propose a reserve for Korean goral in the national Park We employed habitat suitability model, habitat capability model, and the concept of minimum viable population. The results of the study were as follows. First, the carrying capacity and optimal density of gorals in the national park were projected to be 449 gorals, and 251 gorals, respectively Second, since only one patch was projected to satisfy the criteria of minimum viable population (50 individuals/during 50 years), the long term extinction possibility of gorals in the site would be very high. Finally, the patch that satisfy the minimum viable population of goral was proposed as the core zone of the goral reserve and adjacent patches were included as buffer zones.

• The Journal of Fisheries Business Administration
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• v.28 no.1
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• pp.51-70
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• 1997

The fishing industry of Korea is now i a critical transitional stage. That is, broadly speaking, there are two dominant factors that constrain the further development of Korea fishey and effective competition in the international fishing industry. First of all, the global fishing industry has experienced many significant changes due to the execution of U.N, maritime law, the establishment of EEZ(the Exclusive Economic Zones), the increased roles of WTO(the World Trade Organization) as well as Korea being a member of OECD(the Organization for Economic Co-operation and Development). Second, the fishing industry of Korea is faced with the following domestic troubles, such as the icreasing fishing expenses, insufficient labor supply, and the collapse of traditional local co-operative organizations of fishing villages, etc. However, the demand for aquatic products of home consumers not only continues to increase but also is shifting to select more valuable species, completely ignoring the above-mentioned serious pressures incurred by the Korean fishery. To solve these problems and keep developing steadily, it is necessary for the fishing industry of Korea to adopt a more active and flexible development pattern in order to reset up the regional economic base in fishing villages nation-wide and make the exploitation of fishing resources balance. The paper gives an reconsideration to the primary alternatives facing the Korean fishery and its prospective roles in a realistic and far-sighted attitude. It may serve as an endeavour in seeking an outlet for the fishing industry of korea to advance forwardly and lastingly.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.6 no.1
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• pp.50-56
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• 2007

Exhaust manifold is generally subjected to thermal cycle loadings ; at hot condition, large compressive plastic deformations are generated, and at cold condition, tensile stresses are remained in highly deformed critical zones. These phenomena originate from the fact that thermal expansions of the runners are restricted by inlet flange clamped to the cylinder head, because the former is less stiff than the latter and, the temperature of the inlet flange is lower than that of the runners. Since the failure of an exhaust manifold is mainly caused by geometric constraints between the cylinder head and the manifold, the thermal stress can be controlled by geometric factors. The generic geometric factors include the inter distance (2R), the distance from the head to the outlet (L), the tube diameter(d) and the tube thickness (t). This criteria based on elastic analysis up to onset of yield apparently indicate that the pre-stress also reduces the factor; however, high temperature relaxation may reduce this effect at later operation stage.

• Geomechanics and Engineering
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• v.12 no.3
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• pp.483-503
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• 2017

Uncertainty is a fact belonging to engineering practice. An important uncertainty that sets geotechnical engineering is the variability associated with the properties of soils or, more precisely, the characterization of soil profiles. The reason is due largely to the complex and varied natural processes associated with the formation of soil. Spatial variability analysis for the study of the stability of natural slopes, complementing conventional analyses, is able to incorporate these uncertainties. In this paper the characterization is performed in back-analysis for a case of landslide occurred to verify afterwards the presence of the conditions of shear strength at failure. This approach may support designers to make more accurate estimates regarding slope failure responding, more consciously, to the legislation dispositions about slope stability evaluation and future design. By applying different kriging techniques used for spatial analysis it has been possible to perform a 3D-slope reconstruction. The predictive analysis and the areal mapping of the soil mechanical characteristics would support the definition of priority interventions in the zones characterized by more critical values as well as slope potential instability. This tool of analysis aims to support decision-making by directing project planning through the efficient allocation of available resources.

• Proceedings of the KWS Conference
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• 2007.11a
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• pp.276-278
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• 2007

Many processes have been introduced to join PE pipes, but most of these methods have lots of disadvantages such as costs and lack of reliability, etc. Recently due to the benefits of cost, safety and reliability, the but welding has been paid much attention to join PE pipes. In case of butt welding, the heat plate which is used to melt PE pipes is the most critical equipment. In this study, after designed secondary developed heat plate of new shape, the PE double wall pipes were but-welding by using the developed heat plate and secondary developed heat plate and comparison of weld-zones and tensile test were performed. As results of tensile test, tensile strengths using secondary developed heat plate were measured higher $1.17{\sim}1.5$ than using developed heat plate.

• Journal of The Korea Institute of Healthcare Architecture
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• v.26 no.1
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• pp.51-62
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• 2020

Purpose: The Intensive Care Unit (ICU) is an important inpatient care area where critical patients are treated intensively with advanced medical technology. The level of care of ICU and the modernization of related facilities is an important indicator of health care quality. At the present time, when the Regional public hospitals are frequently expanding, the rational planning of the ICU has become an important part of the medical institutions treating the ICU. The purpose of this study is to present basic data with net area which can be used in the architectural planning of the ICU. Methods: The investigation and analysis of the ICUs were conducted on 26 medical facilities, based on theoretical analysis through relevant guidelines, articles, and documents, and on the basis of the actual space composition and net area analysis through the architectural drawings. Results: This study provides basic data such as zone division, spatial composition, relationship between main activities and zones, composition of facilities in the zone and area ratio within each zone. Implications: The results of this paper are expected to be effective reference materials for future research for rational spatial organization and efficient operation of the Intensive Care Unit in regional public hospitals.

• Journal of the Korea institute for structural maintenance and inspection
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• v.4 no.2
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• pp.113-129
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• 2000

This study evaluates the behavior and strength of an anchorage zone of the prestressed concrete box girder bridge on the Kyungboo highway railroad using the 2D SUB-3D STM approach and a linear elastic finite element analysis. The 2D SUB-3D STM approach utilizes several two-dimensional sub strut-tie models that represent the compressive and tensile stress flows of each projected plane of the three-dimensional structural concrete in the selection of a three dimensional strut-tie model, evaluation of the effective strengths of the concrete struts, and verification of the geometric compatibility condition and bearing capacity of the critical nodal zones in the selected three-dimensional strut-tie model. The finite element analysis uses an 8-node brick element and the longitudinal prestressing force is considered as the equivalent nodal force. Analysis results show that the 2D SUB-3D STM approach and linear elastic finite element method can be effectively applied to the analysis and design of three-dimensional structural concrete including a prestressed concrete box girder anchorage zone.

• Structural Engineering and Mechanics
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• v.37 no.1
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• pp.95-110
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• 2011

This paper presents a tri-uniform bond stress model for predicting the lap splice strength of reinforcing bar at the critical bond splitting failure. The proposed bond distribution model consists of three zones, namely, splitting zone, post-splitting zone and yielding zone. In each zone, the bond stress is assumed to be constant. The models for bond strength in each zone are adopted from previous studies. Combining the equilibrium, strain-slip relation and the bond strength model in each zone, the steel stress-slip model can be derived, which can be used in the nonlinear frame analysis of the column. The proposed model is applied to derive explicit equations for predicting the strength of the lap splice strengthened by fiber reinforced polymer (FRP) in both elastic and post-yield ranges. For design purpose, a procedure to calculate the required FRP thickness and the number of FRP sheets is also presented. A parametric investigation was conducted to study the relation between lap splice strength and lap splice length, number and thickness of FRP sheets and the ratio of concrete cover to bar diameter. The study shows that the lap splice strength can be enhanced by increasing one of these parameters: lap splice length, number or thickness of FRP sheets and concrete cover to bar diameter ratio. Verification of the model has been conducted using experimental data available in literature.

• Wind and Structures
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• v.17 no.5
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• pp.515-535
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• 2013

The present study aims to investigate characteristics of the flow structures around the Ahmed body by using both experimental and numerical methods. Therefore, 1/4 scale Ahmed body having $25^{\circ}$ slant angle was employed. The Reynolds number based on the body height, H and the free stream velocity, U was $Re_H=1.48{\times}10^4$. Investigations were conducted in two parts. In the first part of the study, Large Eddy Simulation (LES) method was used to resolve the flow structures around the Ahmed body, numerically. In the second part of the study the particle image velocimetry (PIV) technique was used to measure instantaneous velocity fields around the Ahmed body. Time-averaged and instantaneous velocity vectors maps, streamline topology and vorticity contours of the flow fields were presented and discussed in details. Comparison of the mean and turbulent quantities of the LES results and the PIV results with the results of Lienhart et al. (2000) at different locations over the slanted surface and in the wake region of the Ahmed body were also given. Flow features such as critical points and recirculation zones in the wake region downstream of the Ahmed body were well captured. The spectra of numerically and experimentally obtained stream-wise and vertical velocity fluctuations were presented and they show good consistency with the numerical result of Minguez et al. (2008).

• Earthquakes and Structures
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• v.19 no.6
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• pp.445-457
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• 2020

An ultra-high voltage (UHV) transmission system has the advantages of low circuitry loss, high bulk capacity and long-distance transmission capabilities over conventional transmission systems, but it is easier for this system to cross fault rupture zones and become damaged during earthquakes. This paper experimentally and numerically investigates the seismic responses and collapse failure of a UHV transmission tower-line system crossing a fault. A 1:25 reduced-scale model is constructed and tested by using shaking tables to evaluate the influence of the forward-directivity and fling-step effects on the responses of suspension-type towers. Furthermore, the collapse failure tests of the system under specific cross-fault scenarios are carried out. The corresponding finite element (FE) model is established in ABAQUS software and verified based on the Tian-Ma-Qu material model. The results reveal that the seismic responses of the transmission system under the cross-fault scenario are larger than those under the near-fault scenario, and the permanent ground displacements in the fling-step ground motions tend to magnify the seismic responses of the fault-crossing transmission system. The critical collapse peak ground acceleration (PGA), failure mode and weak position determined by the model experiment and numerical simulation are in relatively good agreement. The sequential failure of the members in Segments 4 and 5 leads to the collapse of the entire model, whereas other segments basically remain in the intact state.