• Journal of Electrical Engineering and Technology
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• v.8 no.4
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• pp.686-693
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• 2013

Generation Expansion Planning (GEP) is one of the most important decision-making activities in electric utilities. Least-cost GEP is to determine the minimum-cost capacity addition plan (i.e., the type and number of candidate plants) that meets forecasted demand within a pre specified reliability criterion over a planning horizon. In this paper, Differential Evolution (DE), and Opposition-based Differential Evolution (ODE) algorithms have been applied to the GEP problem. The original GEP problem has been modified by incorporating Virtual Mapping Procedure (VMP). The GEP problem of a synthetic test systems for 6-year, 14-year and 24-year planning horizons having five types of candidate units have been considered. The results have been compared with Dynamic Programming (DP) method. The ODE performs well and converges faster than DE.

• Korean Management Science Review
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• v.13 no.2
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• pp.193-203
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• 1996

There is no generally accepted definition of information technology (IT) although this is an important issue in the management information systems (MIS) area. In an effort to address this issue, the evolution of IT is reviewed from a historical perspective. A historical review on IT suggests that its evolution be broken down into three stages in a systematic way. Further, the identification of mainstream research interests at each stage makes a contribution in part to defining IT. Two approaches to defining IT are identified, and limitations of each approach are discussed. Finally, a better way to address these limitations is suggested.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2000.04a
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• pp.13-16
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• 2000

In this paper the authors proposed a new anisotropic yield criterion for porous ductile materials. By using the proposed yield criterion and its flow rules a damage evolution of anisotropic sheet under biaxial tensile loading is investigated. A comparison of yield locus and damage evolution between the proposed yield criterion and experiments are carried out. the results are in good agreement.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.10a
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• pp.53-56
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• 2007

Computer simulation of microstructure evolution during hot forging process is of great interest in recent years. Recrystallization model and grain growth model which use a phenomenological approach were summarized. For the waspaloy, upsetting process and cogging process were simulated using $DEFORM^{TM}$ and the change in grain size were investigated in each deformation procedure.

• 한국IT서비스학회:학술대회논문집
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• 2006.11a
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• pp.593-599
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• 2006

Including technical device and general information system, the information-technical(IT) system is defined as the technical system for acquiring, processing, storing and transferring information to a person. This paper presents Knowledge-based Heuristic Evolution Model for creating the advanced information-technical system. This Evolution Model is derived from the historical review on definition of evolution, the research on the architecture of the general IT system, history of IT system, technology innovation theory and multi-case study research. The evolution model is applicable to the conceptual creation of the advanced product in R&D organization requiring development methodologies like rapid-prototyping to develop next generation product. For the detailed theoretical construction and practical application of Evolution Model, the case study research based on action research is performed. the object of the case study is mobile device, especially mobile hand-held phone. Thus, we obtain the Evolution Model for creating the advanced information-technical system.

• Smart Structures and Systems
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• v.14 no.3
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• pp.307-325
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• 2014

A newly developed method based on energy is presented to study the damage pattern of FRP material. Basalt fiber reinforced polymer (BFRP) is employed to monitor the damage under fatigue loading. In this study, acoustic emission technique (AE) combined with scanning electronic microscope (SEM) technique is employed to monitor the damage evolution of the BFRP specimen in an approximate continuous scanning way. The AE signals are analyzed based on the wavelet transform, and the analyses are confirmed by SEM images. Several damage patterns of BFRP material, such as matrix cracking, delamination, fiber fracture and their combinations, are identified through the experiment. According to the results, the cumulative energy (obtained from wavelet coefficients) of various damage patterns are closely related to the damage evolution of the BFRP specimens during the entire fatigue tests. It has been found that the proposed technique can effectively distinguish different damage patterns of FRP materials and describe the fatigue damage evolution.

• Geomechanics and Engineering
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• v.20 no.1
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• pp.29-41
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• 2020

It is extremely important to obtain rock strength parameters for geological engineering. In this paper, the evolution of sandstone cohesion and internal friction angle with plastic shear strain was obtained by simulating the cyclic loading and unloading tests under different confining pressures using Particle Flow Code software. By which and combined with the micro-crack propagation process, the mesoscopic mechanism of parameter evolution was studied. The results show that with the increase of plastic shear strain, the sandstone cohesion decreases first and then tends to be stable, while the internal friction angle increases first, then decreases, and finally maintains unchanged. The evolution of sandstone shear strength parameters is closely related to the whole process of crack formation, propagation and coalescence. When the internal micro-cracks are less and distributed randomly and dispersedly, and the rock shear strength parameters (cohesion, internal friction angle) are considered to have not been fully mobilized. As the directional development of the internal micro-fractures as well as the gradual formation of macroscopic shear plane, the rock cohesion reduces continuously and the internal friction angle is in the rise stage. As the formation of the macroscopic shear plane, both the rock cohesion and internal friction angle continuously decrease to a certain residual level.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.6
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• pp.600-607
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• 2006

For the effective operation of manufacturing system, FMS(Flexible Manufacturing System) and CIM(Computer Integrated Manufacturing) system are developed. In these systems, a machine tool is the target of integration in last 3 decades. In nowadays, the conventional concept of machine tools is changing to the autonomous manufacturing device based on knowledge-evolution through applying advanced information technology in which open architecture controller, high speed network and internet technology are contained. In this environment, a machine tool is not the target of integration but the subject of cooperation. In the future, a machine tool will be more improved in the form of a knowledge-evolution based device. In order to develop the knowledge-evolution based machine tools, this paper proposes the structure of knowledge evolution in M2M(Machine To Machine) and the scheme of a dialogue agent among agent-based modules such as a sensory module, a dialogue module, and an expert system. The dialogue agent has a role of interfacing with another machine for cooperation. To design the dialogue agent module in M2M environment, FIPA-OS and ping agent based on FIPA-OS are analyzed in this study. Through this, it is expected that the dialogue agent module can be more efficiently designed and the knowledge-evolution based machine tools can be hereafter more easily implemented.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.265-267
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• 2005

본 논문에서는 무선 랜과의 인터워킹 등 새로운 특징을 갖는 주요 기능들을 추가하기 위한 기반 시스템인 3G Evolution 시스템 개발에 필요한 액세스 시스템 내의 서브 시스템인 RRCS(Radio Resource Control Subsystem)를 구현 및 검증하기 위하여 단말-기지국간 무선 액세스 프로토콜을 형식 기술 언어인 SDL(Specification and Description Language)을 이용해 구현하였다. 여기서 효율적 시스템 설계를 위해 복잡한 각 메시지 처리 함수는 C 언어를 이용해 라이브러리화하고 이를 SDL 시스템 내에서 호출하도록 지원하는 방법을 사용했다.

• STI Policy Review
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• v.2 no.1
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• pp.1-12
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• 2011

Korea is examining how to coordinate its S&T policies and solidify its position as a leader of infrastructure innovation policy that forms the foundation for many different policies. A number of questions have been raised, such as whether to install a superior coordinating body like the National Science and Technology Council (NSTC) or separate the budget allocation and coordination authority from the budget-planning ministry. Korea has tried using various institutional coordination devices and functions such as reorganizing its administrative ministries based on related functions and installing or reinforcing a superior coordinating body. In line with these discussions, the strengthening of the S&T policy coordination function through the NSTC is currently under review. In order to design an effective S&T coordination system in step with changing political and social demands, it is important to have a clear recognition of the current context as well as the unique institutional characteristics of Korea. This study examines the evolution of Korea's S&T policy coordination systems and analyzes its features.