• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.4
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• pp.42-51
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• 2018

Verticality problem during the installation process in offshore wind turbine substructures could degrade the safety of the whole structures. Therefore, in this paper, the design of vertically adjustable transition piece(T.P.), using a PS anchor and grout of anchor socket in concrete gravity based substructure(G.B.S.), was proposed. T.P. was designed for 5MW offshore wind trubine and can adjust up to $0.5^{\circ}$ in verticality, occurred during installation. The design plan for each members and design procedure for T.P. was proposed. Then based on the proposed design, actual design targeting sea of Jeju-island was carried out. Finally, by use of non-linear 3D Finite Element Analysis(F.E.A.), evaluation of design was performed. As a result of evaluation, by checking load transfer mechanism and stress of T.P, proposed design was considered safe up to $0.5^{\circ}$ of adjustment.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.3
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• pp.479-486
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• 2012

This paper presents a high-speed automatic micro-alignment system that is a part of an inspection machine for small-sized molded lenses of mobile phones, palm-top computers, and so on. This work was motivated by the shortcomings of existing highest-grade commercial machine. A simple tip/tilt/Z parallel mechanism is designed based on kinematic couplings, which is a 3-degree-of-freedom (3-DOF) moderate-cost alignment stage. It is used to automatically adjust the posture of each lens on the tray, which is impossible by the conventional instrument. Amplified piezoelectric actuators are used to ensure the accuracy and dynamic response. Forward kinematic analysis and simulation show that the parasitic motion is small enough compared to the actuator stroke. From the workspace analysis of the moving platform, it is clear that the output motion range satisfies the design requirements.

• Journal of the Korea Society of Computer and Information
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• v.26 no.8
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• pp.1-11
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• 2021

This paper proposes a novel mechanism called Event-driven Uncore Frequency Scaler (eUFS) to improve the energy efficiency of the HPC systems. UFS exploits the hardware events such as LAPI (Last-level Cache Accesses Per Instructions) and CPI (Clock Cycles Per Instruction) to dynamically adjusts the uncore frequency. Hardware events are collected at a reference time period, and the target uncore frequency is determined using the collected event and the previous uncore frequency. Experiments with the NPB benchmarks demonstrate that the eUFS reduces the energy consumption by 6% on average for class C and D NPB benchmarks while it only increases the execution time by 2% on average.

• Composites Research
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• v.22 no.4
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• pp.1-12
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• 2009

In this paper, quasi-static crushing tests of composite circular tubes under axial compression load are conducted to investigate the energy absorption characteristics. Circular tubes used for this experiment are glass/epoxy (GFRP) composite tubes which are fabricated by the filament winding method. One edge of the composite tube is chamfered to reduce the initial peak load and to prevent catastrophic failure during crushing process. Energy absorption characteristics vary significantly according to the constituent materials, fabrication conditions, tube geometry and test condition. In tube geometry, according as inner diameter increase, unstable crush mode is caused by local buckling of delamination, but control of the fiber orientation should help composite tubes get stable crush mode.

• Environmental and Resource Economics Review
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• v.31 no.3
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• pp.419-449
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• 2022

This paper aims to quantify the potential economic burdens of EU's carbon border adjustment mechanisms faced by Korean domestic industries. In addition, this study tries to compare and analyzes changes in the burden of each industry resulted from the implementation of the domestic low-carbon policy. Based on the quantitative findings, we intend to suggest policy implications for establishing mid- to long-term strategies in response to climate change risks. Based on the environmentally extended input-output analysis, the total economic burdens of the domestic industries due to the EU's carbon border adjustment mechanisms are estimated to be approximately KRW 8,245.6 billion in 2030. Looking at the impacts by industry, it is found that major industries such as petrochemicals, petroleum refining, transportation equipment, steel, automobiles, and electric/electronic equipment industries are expected to account for 84.3% of the total potential burdens. In addition, in multiple policy scenarios assuming technological developments and energy transition following the implementation of domestic low-carbon policies, the total economic burden of carbon border adjustment is expected to decrease by about 11.7% to 15.0%. The main result of this study suggests that we should not view EU EU's carbon border adjustment mechanism as a trade regulation, but to use it as a momentum for more effective implementation of the low-carbon and energy transition strategies in the global carbon neural era.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.15 no.5
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• pp.321-327
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• 2022

In this paper, a wrinkled structure was formed on the PDMS surface through UV/Ozone treatment, and the wrinkle structure formation mechanism was revealed through physicochemical characterization. A wrinkle structure was formed on the PDMS surface through UV/Ozone treatment for 30 min, and periodic wrinkle formation on the PDMS surface was confirmed by cross-sectional imaging of the scanning electron microscope. In addition, through x-ray photoelectron spectroscopy spectral analysis, it was confirmed that the silica-like-surface of SiOx on the PDMS surface was formed by UV/Ozone. The results of this study not only improve the understanding of the mechanism of wrinkle structure formation on the PDMS surface by UV/Ozone treatment, but also can be used as a basic study to adjust the amplitude and period of the wrinkle structure according to UV/Ozone irradiation conditions in the future.contact angles and the surface energies of FSAMs, it was confirmed that pretilt angles of LC molecules increased according to the alkyl chain length. High optical transparency and uniform homeotropic LC alignment characteristics of FSAMs showed the possibility of FSAMs as an LC alignment layers.

• KNOM Review
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• v.22 no.1
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• pp.1-10
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• 2019

The process to determine the required number of resources depends on the factors being considered. Autoscaling is one such mechanism that uses a wide range of factors to decide and is a critical process in NFV. As the networks are being shifted onto the cloud after the invention of SDN, we require better resource managers in the future. To solve this problem, we propose a solution that allows the VNFMs to autoscale the system resources depending on the factors such as overhead of hyperthreading, number of requests, execution-times for the virtual network functions. It is a known fact that the hyperthreaded virtual-cores are not fully capable of performing like the physical cores. Also, as there are different types of core having different frequencies so the process to calculate the number of cores needs to be measured accurately and precisely. The platform independency is achieved by proposing another solution in the form of a monitoring microservice, which communicates through APIs. Hence, by the use of our autoscaling application and a monitoring microservice, we enhance the resource provisioning process to meet the criteria of future networks.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 1999.10a
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• pp.291-300
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• 1999

인터넷을 기반으로 한 정보통신의 급속한 발전이라는 기업환경의 변화에 적응하기 위해서 기업은 점차 모든 경영시스템을 인터넷을 기반으로 하도록 변화시키고 있을 뿐만 아니라, 기업 조직 또한 전세계를 기반으로한 글로벌 기업 형태로 변화하고 있다. 이러한 급속한 경영환경의 변화로 인해서 기업 내에서는 종전과는 다른 형태의 부서간 상호의사결정조정 과정이 필요하게 되었다. 일반 기업들을 대상으로 한 상호의사결정의 지원과정에 대해서는 기존에 많은 연구들이 있었으나 글로벌기업과 같은 네트워크 형태의 새로운 형태의 기업에 있어서의 상호의사결정과정을 지원할 수 있는 의사결정지원시스템에 대해서는 단순한 그룹의사결정지원시스템 또는 분산의사결정지원시스템과 같은 연구들이 주를 이루고 있다. 따라서 본 연구에서는 인터넷 특히, 웹을 기반으로 한 기업의 글로벌경영 및 분산 경영에서 비롯되는 부서간 상호의사결정이라는 문제를 효율적으로 지원할 수 있는 기업의 글로벌경영 및 분산 경영에서 비롯되는 부서간 상호의사결정이라는 문제를 효율적으로 지원할 수 있는 메커니즘을 제시하고 이에 기반한 프로토타입 형태의 시스템을 구현하여 성능을 검증하고자 한다. 특히, 기업 내에서 가장 대표적으로 상호의사결정지원이 필요한 생산과 마케팅 부서를 대상으로 상호의사결정지원 메커니즘을 개발하고 실험을 진행하였다. 그 결과 글로벌 기업내의 생산과 마케팅 부서간 상호의사결정을 효율적으로 지원 할 수 있는 상호조정 메카니즘인 개선된 PROMISE(PROduction and Marketing Interface Support Environment)를 기반으로 한 웹 분산의사결정지원시스템 (Web-DSS : Web-Decision Support Systems)을 제안하는 바이다.자대상 벤처기업의 선정을 위한 전문가시스템을 구축중이다.의 밀도를 비재무적 지표변수로 산정하여 로지스틱회귀 분석과 인공신경망 기법으로 검증하였다. 로지스틱회귀분석 결과에서는 재무적 지표변수 모형의 전체적 예측적중률이 87.50%인 반면에 재무/비재무적 지표모형은 90.18%로서 비재무적 지표변수 사용에 대한 개선의 효과가 나타났다. 표본기업들을 훈련과 시험용으로 구분하여 분석한 결과는 전체적으로 재무/비재무적 지표를 고려한 인공신경망기법의 예측적중률이 높은 것으로 나타났다. 즉, 로지스틱회귀 분석의 재무적 지표모형은 훈련, 시험용이 84.45%, 85.10%인 반면, 재무/비재무적 지표모형은 84.45%, 85.08%로서 거의 동일한 예측적중률을 가졌으나 인공신경망기법 분석에서는 재무적 지표모형이 92.23%, 85.10%인 반면, 재무/비재무적 지표모형에서는 91.12%, 88.06%로서 향상된 예측적중률을 나타내었다.ting LMS according to increasing the step-size parameter $\mu$ in the experimentally computed. learning curve. Also we find that convergence speed of proposed algorithm is increased by (B+1) time proportional to B which B is the number of recycled data buffer without complexity of computation. Adaptive transversal filter with proposed data recycling buffer

• Journal of the Korean Geotechnical Society
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• v.38 no.4
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• pp.33-45
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• 2022

A series of model tests were performed in this study to demonstrate the clogging mechanism created during the installation of a compaction pile to improve soft ground. The application of an air-jet to extrude sand or aggregates from a casing during the installation of a compaction pile imposes a remarkably high-pressure difference between the composite soil layers of clay and sand (or aggregates), resulting in severe clogging. Therefore, a one-dimensional testing system was developed to simulate composite soil layers consisting of clay and sand (or aggregates) and to apply a high-pressure differential at both boundaries, thus replicating the extrusion process used in compaction pile installation. Herein, the performance of two construction materials for compaction piles of crushed stone and grading-controlled aggregates was compared. A series of one-dimensional model tests were performed under multiple pressure settings, with clogging depth and permeability measured in each case. Results indicate that, blinding clogging mechanisms and blocking defined by previous studies were observed for crushed stone, and a new mechanism of "infiltration" was revealed and defined. Whereas, the controlled aggregates performed excellently against clogging because only blinding was observed.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06d
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• pp.208-210
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• 2006

그리드 환경에서는 원격의 이질적인 자원들을 서로 공유하며 상호 접근이 가능하도록 하여 사용자의 작업을 처리 할 수 있는 메커니즘을 제공한다. 하지만 각 노드들은 그리드에 자유롭게 참여 및 탈퇴가 가능하다는 점에서 P2P 네트워크 구조와 매우 유사하기 때문에 기존의 병렬처리 컴퓨터에서의 부하 균형문제와는 다른 특징을 갖게 된다. 본 논문에서는 동적인 자원 구성의 특징을 갖는 그리드 컴퓨팅 환경에서 발생할 수 있는 부하 균형 문제를 정의하고 이를 해결하기 위해 조정 노드(coordinating node)라고 불리는 부하 탐지 모듈을 설계 및 구현한다. 본 논문에서 제안된 조정 노드는 동적으로 변화하는 그리드 자원들의 상태를 실시간으에 탐지하게 되며 각 노드들이 네트워크에 새롭게 참여/탈퇴하여 네트워크 위상이 변화하는 경우에도 부하 균형을 달성 하게 된다.