• Journal of Communications and Networks
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• 제2권1호
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• pp.18-34
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• 2000

The evolution of mobile communications is inducting several new issues belonging to the system engineering disciplines. this paper tires to underline some of the most important problems staring room the novel requirements and the application characteristics expected for Third Generation Mobile System. Based on these new service peculiarities. the radio resource control and the architectural solutions to be chosen for the Mobile core network are becoming key issues to be investigated for the forthcoming configurations. Particularly. the service acceptance control and the perspective of integration with the IP (internet Protocol) context are of great importance for the definition of the radio control functions and the specification of the switching and nobility control features respectively．The paper presents some basic considerations on the cellular planning issues arising in W-CDMA ( wideband -code division Multiple access) systems. by underlying the most significant innovative elements that are to be introduced in the planning process form the mobile operator viewpoint..

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2003년도 춘계공동학술대회
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• pp.1048-1055
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• 2003

This paper proposes a new method of solving integrated problems that consist of several sub-problems in a symmetric multi-layered structure, and also demonstrate the applicability of the method. The proposed method is named Symmetric Multi-layered Coevolutionary Algorithm (SMCA). The SMCA imitates partly the natural process of endosymbiotic evolution, which is a special type of coevolution. The SMCA is applied to the process planning problem in flexible manufacturing system (FMS), taking account of the flexibility of machine, tool, process, and sequence. To do this, SMCA's components are studied and its strategies are developed to improve the performance. The proposed algorithm is compared with the existing ones in terms of solution quality. The experimental results confirm the effectiveness of our approach.

• Structural Monitoring and Maintenance
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• 제2권2호
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• pp.133-143
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• 2015

Civil engineering infrastructure is aging and requires cost-effective maintenance strategies to enable infrastructure systems operate reliably and sustainably. This paper presents an approach for determining risk-cost balanced repair strategy of corrosion damaged reinforced concrete structures with consideration of uncertainty in structural resistance deterioration. On the basis of analytical models of cover concrete cracking evolution and bond strength degradation due to reinforcement corrosion, the effect of reinforcement corrosion on residual load carrying capacity of corroded reinforced concrete structures is investigated. A stochastic deterioration model based on gamma process is adopted to evaluate the probability of failure of structural bearing capacity over the lifetime. Optimal repair planning and maintenance strategies during the service life are determined by balancing the cost for maintenance and the risk of structural failure. The method proposed in this study is then demonstrated by numerical investigations for a concrete structure subjected to reinforcement corrosion. The obtained results show that the proposed method can provide a risk cost optimised repair schedule during the service life of corroded concrete structures.

• 대한건축학회논문집:계획계
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• 제34권3호
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• pp.73-84
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• 2018

The purpose of this study is to analyze the contents of the cultural heritage conservation standards those have been developed throughout the century to reveal the evolution of the conservation. The analysis targets are prepared principles in response to the risks posed by armed conflicts, improper modifications, risks caused by urban planning and development, and the risk posed by environmental impacts. The study analyzed how conservation targets, issues, and conservation methods have changed. The analysis showed that the results of changed trend of conservation, first, the segmentation and diversification of the conservation targets, second, the integrated approaches, third, risk perception changes due to indirect effects from direct risk factors, forth, changes of conservation from safeguard to sustainable development.

• 대한두개안면성형외과학회지
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• 제23권5호
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• pp.193-204
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• 2022

Tongue reconstruction remains a major aspect of head and neck reconstructive procedures. Surgeons planning tongue reconstruction should consider several factors to optimize the overall outcomes. Specifically, various technical aspects related to tongue reconstruction have been found to affect the outcomes. Multidisciplinary teams dedicated to oncologic, reconstructive, and rehabilitative approaches play an essential role in the reconstructive process. Moreover, operative planning addressing certain patient-related and defect-related factors is crucial for optimizing functional speech and swallowing, as well as quality of life outcomes. Furthermore, tongue reconstruction is a delicate process, in which overall functional outcomes result from proper flap selection and shaping, recipient vessel preparation and anastomosis, surgical approaches to flap insetting, and postoperative management. The second part of this review summarizes these factors in relation to tongue reconstruction.

• 대한교통학회:학술대회논문집
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• 대한교통학회 1998년도 Proceedings The 4th International Transport Symposium
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• pp.135-140
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• 1998

Social and economic development needs the support of transportation and communications and in turn the development level of society and economy affects urban traffic demand and determines the investment scale of transportation facilities. In the paper based on the analysis of the evolution of urban transportation in Shanghai in the past ten years and the economic background of that period, the urban transportation in the future development of economy is generally prospected.

• 대한교통학회지
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• 제22권3호
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• pp.159-166
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• 2004

도로용량편람에서 정의하고 있는 용량은 하류부에 용량을 제한하는 요소가 없다는 것을 가정한 정상교통류에 대한 용량 개념으로서, 이는 전통적으로 계획, 설계, 현재 및 장래 도로시설의 운영상태 분석 등에 사용되어 왔다. 실시간 제어는, 용량을 초과하지 않는 교통류를 유지시켜 혼잡교통류로의 전이를 막고, 물리적 여건이나 제반 확률적 요인으로 혼잡이 발생하였을 경우 조속히 용량이하로 교통량을 떨어뜨려 정상교통류로 회복시키는 데 목표를 둔다. 이러한 맥락에서 용량은 실시간 제어의 효과를 좌우하는 중요한 입력변수이며, 정상교통류 상태라면 혼잡으로 전이되지 않을 임계치로서의 용량 산정이 중요한 관건이다. 그러나 혼잡교통류 상태에서 정상교통류로 되도록 빨리 회복시켜 주기 위한 제어 기준으로서의 용량은, 하류부 혼잡의 시공간적 전개에 따라 변하는 값이어야 하며 이러한 동적 용량변화를 정확히 예측할 수 있는 방법론이 요구된다. 이에 본 연구에서는 기존의 용량 개념을 출력 개념의 용량으로 정의하고, 입력 개념의 용량을 최대가능처리량(Maximum Sustainable Throughput)으로 새롭게 정의하였다. 이 최대가능처리량은 혼잡의 시공간적 전개에 따라 결정되는 동적 용량이며, 이러한 혼잡의 시공간적 전개는 Newell의 단순화된 교통량-밀도 모형으로 예측할 것을 제안하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.361-364
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• 2005

The use of remotely sensed data and geographic information system (GIS) to develop conservation-oriented watershed management strategies on Imha Dam, Korea, is presented. The change of land use for study area was analyzed using multi-temporal Landsat imagery. A soil loss model was executed within a GIS environment to evaluate watershed management strategies in terms of soil loss. In general, remotely sensed data provide efficient means of generating the input data required for the soil loss model. Also, GIS allowed for easy assessment of the relative erosion hazard over the watershed under the different land use change options. The soil loss model predicted substantial declines in soil loss under conservation-oriented land management compared to current land management for Imha Dam. The results of this study indicate that soil loss potential (5,782,829 ton/yr) on Imha Dam in 2003 is approximately 1.27 times higher than that (4,557,151 ton/yr) in 1989. This study represents the first attempt in the application of GIS technology to watershed conservation planning for Imha Dam. The procedures developed will contribute to the evolution of a decision support system to guide the land planning and dam management in Imha Dam.

• Strategy21
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• 통권39호
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• pp.198-241
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• 2016

Aircraft carriers: are they national platforms to maximize national interest or just simply paper tigers to be little useful for states' development? To some states such as U.S., U.K, and France, aircraft carriers functioned as national assets which is indispensable to their interest. By contrast, Thailand's aircraft carrier was a dead platform which is useless to its national interest and India's ones were little used on the mission field. What is the mechanism leading to this difference? The key is whether states make aircraft carriers connected to overall national evolution when it comes to establishing military strategy and planning a long-term force structure. Put it another way, conditions to acquire them need to be analyzed regarding two variables-national status(prestige and economic power) and threat(mission)-for the future as well as in the present. The former acquired carriers under the condition of making them becoming national platforms which is balanced with their overall development. However, the latter simply bought them without carefully taking account of economic obstacles, e.g., the poverty rate, when it comes to force planning. At the same time, we should not neglect to identify that states of the former cases might have a hard time in maximizing their key interests if they did not have carriers. Accordingly, conditions on carriers' acquisition need to be carefully examined and a typological theory suggested here could shed light on this process. This theory shows that South Korea's status is eligible to have a necessary and sufficient condition to acquire carriers.

• 한국경영과학회지
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• 제26권4호
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• pp.133-141
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• 2001

Rapid development in computer and network technology these days has created in environment in which decisions for manufacturing companies can be made in a much broader perspective. Especially, better decisions on production and distribution planning(PDP) problems can be made laking advantage of real time information from all the parties concerned. However, since the PDP problem-a core part of the supply chain management- is known to be the so-called NP-hard problem, so heuristic methods are dominantly used to find out solutions in a reasonable time. As one of those heuristic techniques, many previous studios considered genetic a1gorithms. A standard genetic a1gorithm applies rules of reproduction, gene crossover, and mutation to the pseudo-organisms so the organisms can pass along beneficial and survival-enhancing trails to a new generation. When it comes to representing a chromosome on the problem, it is hard to guarantee an evolution of solutions through classic a1gorithm operations alone, for there exists a strong epitasis among genes. To resolve this problem, we propose a hybrid genetic a1gorithm based on Silver-Meal heuristic. Using IMS-TB(Intelligent Manufacturing System Test-bed) problem sets. the good performance of the proposed a1gorithm is demonstrated.