• International Journal of High-Rise Buildings
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• v.4 no.1
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• pp.65-73
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• 2015

Detailed finite element (FE) analyses of a full-scale four-story steel frame structure, subjected to consecutive 60% and 100% excitations from the JR Takatori records during the 1995 Hyogoken-Nanbu earthquake, are conducted using E-Simulator. The four-story frame was tested at the largest shake-table facility in the world, E-Defense, in 2007. E-Simulator is a parallel FE analysis software package developed to accurately simulate structural behavior up to collapse by using a fine mesh of solid elements. To reduce computational time in consecutive dynamic time history analyses, static analysis with gravity force is introduced to terminate the vibration of the structure during the analysis of 60% excitation. An overall sway mechanism when subjected to 60% excitation and a story mechanism resulting from local buckling of the first-story columns when subjected to 100% excitation are simulated by using E-Simulator. The story drift response to the consecutive 60% and 100% excitations is slightly smaller than that for the single 100% excitation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.6
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• pp.120-129
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• 2007

Rapid urbanization has transformed the spatial pattern of urban land use or cover. This paper concentrates that changed characteristics of landscape structure in the Tancheon Watershed, from 1995 to 2003 were investigated using land cover map. We used FRAGSTATS software to calculate landscape indices to characterize the landscape structure. We found that built up area has been increased rapidly during the study period, while cultivated area and forest area have been decreased rapidly in the same period. From 1995 to 2003, built up area was increased from 19.73% to 39.62% and cultivated area and forest area was decreased 17.60% to 5.97% and 58.31% to 49.41%. Number of patches, mean euclidean nearest-neighbor distance, contagion index, Shannon's diversity index increased considerably from 1995 to 2003, also suggesting the landscape in the study area became more fragmented and heterogeneous. but because of continuously fragmentation, landscape became homogeneity. The study demonstrates that landscape metrics can be a useful indicator in landscape monitoring and landscape assessment.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.5
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• pp.146-153
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• 2010

Urban development typically results in many species being confined to small, isolated and degraded habitat fragments. Fragment size and isolation underpin many studies of modified landscape to prevent biodiversity loss. However, habitat characteristics such as vegetation structure and edge effects are less frequently incorporated in planning. The relative influence of biogeographic (e.g. size, isolation) and vegetation parameters on assemblages is poorly understood, but critical for conservation management. In this study, the relative importance of biogeographic and vegetation parameters in explaining the diversity of forest-interior dwelling birds in forest fragments in Chungcheong Province Area. Fragment size and vegetation characteristics were consistently important predictors of bird diversity. Forestinterior bird richness was influenced by fragment size (0.437), wood age (0.332), wood diameter (0.068), and patch shape (-0.079). To preserve bird diversity of Chungcheong Province Area, it is important to consider differing responses of bird diversity to landscape change, move beyond a focus primarily on spatial attributes (size, isolation) to recognize that landscape change also has profound effects on habitat composition and quality. The result is very useful for long-term aspect of biodiversity conservation plan in regional scale.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1293-1299
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• 2010

Daegu urban railroad line 3 is introduced with straddle-type monorail system within the country at the first time. This system is long line with 24km in total length which has not the results of construction in Korea. The rail beam of monorail bridge to be constructed/ installed in the city is adopted on the basis of the PSC rail beam. It is required to apply the steel rail beam at rapid/ curved line parts or location to be required the long span bridge as passing river and intersection. The composition of span bridge is various and the height of bridge is change with each section and exist the different curve radius due to all section is passes in the city. The rail beam shall be considered the ground conditions and then consider the construction methods. It is analyzed to construction period of PSC rail beam to be linked with period of infrastructure construction and construction of steel rail beam, structure construction of station etc. It is compared to crane construction methods and launching girder as alternative construction methods and propose to upper construction methods which is superior in economic and construction.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.6
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• pp.225-240
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• 2022

Gyeonggi-do comprises several types of areas, including urban, semi-urban, and rural areas. The availability of public transportation services varies depending on the area types, but the fare structure is based on a simple transfer rule, i.e., a transfer is free when completed within 30 minutes. As a result, users in non-urban areas with a poor frequency of public transportation services do not receive transfer discounts because most of the bus routes in these areas have a gap of more than 30 minutes between services. In terms of equality of opportunity, the transfer rule is being applied unfavorably and, as a result, equality of opportunity of the non-urban commuter is severely affected. Therefore, this study analyzed the user benefits mainly stemming from transfer fares using the smart card data of commuters using public transportation in Gyeonggi-do. An index called the beneficiary rate of the free transfer was developed and a scenario analysis was conducted based on the various levels of the rate. The results of this analysis proved that the users of public transportation services in non-urban areas in Gyeonggi-do can only receive transfer benefits by the extended time for free transfer and not by the implementation of a uniform policy irrespective of the type of area. The study also suggested an equitable fare transfer system and policy alternatives.

• Health Policy and Management
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• v.28 no.3
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• pp.226-232
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• 2018

The objectives of this study were to evaluate the current state of governance structure and management of the health system to achieve the goals of the health system in South Korea, and to propose reform plan. This study drew implications from the governance of United Kingdom, Germany, and Netherlands, based on the principle of health system proposed by World Health Organization. The presidency and the health ministry should make macroscopic decision-making. The government has to decentralize the enforcement by municipality to operate public health and national health insurance (NHI), and to distribute the centralized NHI fund by municipality. The front line health centers and community centers should provide integrated health and social services. The government has to establish diversified regulatory bodies to enhance both the patient-centered care and the efficiency and equity of health care, and to provide mechanisms for ensuring autonomy of providers. The governance of the health system should be composed of the centralization of macro decision-making, the decentralization of implementation by municipality, the integration of health and social services on the front line, and the well-balanced regulation and autonomy on both consumers and suppliers.

• Journal of the Korean Geographical Society
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• v.29 no.3
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• pp.281-296
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• 1994

It is generally accepted that there is always a potential for crisis in the capitalist society because of the internal contradiction of capitalism. The contradiction is explicitly and implicitly expressed in space. The fundamental contradiction in capitalism, however, is controlled and mediated by the state (i.e., the capitalist state). We thus could argue that the state plays an important role in the capitalist society and in the capitalist spatial formation. It is necessary to note how and why spatial structure has developed unevenly in capitalist societies, particularly in the U.S., The general concept of uneven geographical development is understood in the context of the capitalist economic system and the role of the state. But the problem is that the capitalist state itself has a contradiction between the productive function (i.e., accumulation function) and the reproductive function (i.e., legitimation function). The compromise of the two functions is always the dilemma of the state and the state becomes the object of class struggle (e.g., political class struggle) . The research questions are as follows. First, what is the role of the state in the economic structure and what is the internal problem of the state\ulcorner Second, what is the role of the state in space economy (or in spatial structure)\ulcorner And last, what is the relation between the federal state and the local state in the U.S. and how does the relation form the urban policies and thus the urban and regional development\ulcorner The paper will be looking at how the political economy in the U.S. explains unevenly developed geographical phenomenon.

• Journal of Korea Trade
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• v.24 no.2
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• pp.15-30
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• 2020

Purpose - This paper investigates the theories and practices of Most-Favored-Nation (MFN) clauses. The MFN clause became a controversial issue during the past two decades, especially in the context of investment arbitration. This paper aims to clarify a reasonable way to apply MFN clauses. It in particular focuses on the territoriality requirements and the scope of investment activity which are common features included in most of investment treaties. Design/methodology - This paper analyses two investment arbitration cases, Ansung Housing and Beijing Urban Construction. Through the case study, this paper reveals limitations of the currently dominant views on the operation of MFN clauses. It then tries to reconstruct the system of MFN application within the relevant arbitration principles. Findings - Tribunals of recent investment arbitration as represented in the two cases above employed strict literal interpretation of the treaty provisions, especially of the phrase "in its territory". This paper finds a more functional interpretation is appropriate and consistent with theories of public international law and developments of global economy. Originality/value - Existing studies either stuck to literal interpretation or suggested more flexible interpretation of the phrase "in its territory" without full explanation. This paper tries to fill the gap in the existing discussion by analyzing legal foundations and theoretical structure for an effective interpretation of MFN clauses.

• Journal of Korean Society of Transportation
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• v.14 no.1
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• pp.101-116
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• 1996

Increased attention has been paid in recent years to the need of traffic management for alleviating urban traffic congestion. This paper presents a discrete event modeling and simulation framework for analyzing the traffic flow. Traffic simulation models can be classified as being either microscopic and macroscopic models. The discrete event modeling and simulation technique can be basically employed to describe the macroscopic traffic simulation model. To do this, we have employed the System Entity Structure/Model Base (SES/MB) framework which integrates the dynamic-based formalism of simulation with the symbolic formalism of AI. The SES/MB framework supports to hierarchical, modular discrete event modeling and simulation environment. We also adopt the Symbolic DEVS (Discrete Event System Specification) to developed the automated analysis methodology for generating optimal signal light policy. Several simulation tests will demonstrates the techniques.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.9
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• pp.599-608
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• 2022

Urban air mobility (UAM) equipped with rotor system is subject to ground effect at vertiport during takeoff and landing. The aerodynamic performance of the aircraft in ground effect should be analyzed for the safe operation. In this study, The ground effects on the aerodynamic performance and wake structure of the quadcopter electric vertical takeoff and landing (eVTOL) configuration equipped with coaxial counter-rotating propellers were investigated by using the lattice Boltzmann method (LBM). The influence of the ground effect was observed differently in the upper and lower propellers of the coaxial counter-rotating propeller system. There was no significant change in the aerodynamic performance of the upper propeller even if the propeller height above the ground was changed, whereas the averaged thrust and torque of the lower propeller increased significantly as propeller height decreased. In addition, the amplitude of the thrust fluctuation tended to increase as the propeller height decreased. The propeller wake was not sufficiently propagated downstream and was diffused along the ground due to the outwash flow developed by the ground effect. The impingement of the rotor wakes on the ground and a fountain vortex structure were observed.