• The Journal of the Korea Contents Association
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• v.15 no.4
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• pp.9-16
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• 2015

On modern operating systems such as Linux, virtual memory is a general way to provide a large address space to applications by using main memory and storage devices. Recently, storage devices have been improved in terms of latency and bandwidth, and it is expected that applications with large memory show high-performance if next-generation storage devices are considered. However, due to the overhead of virtual memory subsystem, the paging system can not exploit the performance of next-generation storage devices. In this study, we propose several optimization techniques to extend memory with next-generation storage devices. The techniques are to allocate block addresses of storage devices for write-back operations as well as to configure the system parameters, and we implement the techniques on Linux 3.14.3. Our evaluation through using multiple benchmarks shows that our system has 3 times (/24%) better performance on average than the baseline system in the micro(/macro)-benchmark.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.6
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• pp.52-61
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• 2015

Personal distance is one of the basic and important concepts in the field of Environmental Psychology in influencing personal space, visible or invisible territoriality and psychological carrying capacity of contemporary urban dwellers. This study aims to analyze the bench users' behaviour and personal distances in urban parks for the first time in Korea, one of the representative landscape spaces in urban areas. For these purposes, this study has adopted a blind observation and pictorial analysis for bench users in Yeouido Park in Seoul. The main results of this study show that the average interpersonal distance between female and male(intimate relationship) is 47.5cm, the distance between female and female is 53.2cm, and the distance between male and male is 70.3cm. These results mostly support the previous western study results, but the interpersonal space and territoriality of Koreans in urban parks may be smaller than that for western societies.

• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.4 s.44
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• pp.55-66
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• 2005

The effectiveness of fuzzy supervisory control technique for the control of seismic responses of smart base isolation system is investigated in this study. To this end, first generation base isolated building benchmark problem is employed for the numerical simulation. The benchmark structure under consideration is an eight-story base isolated building having irregular plan and is equipped with low-damping elastometric bearings and magnetorheological (MR) dampers for seismic protection. Lower level fuzzy logic controllers (FLC) for far-fault or near-fault earthquakes are developed in order to effectively control base isolated building using multi-objective genetic algorithm. Four objectives, i.e. reduction of peak structural acceleration, peak base drift, RMS structural acceleration and RMS base drift, are used in multi-objective optimization process. When earthquakes are applied to benchmark building, each of low level FLCs provides different command voltage and supervisory fuzzy controller combines two command voltages io one based on fuzzy inference system in real time. Results from the numerical simulations demonstrate that base drift as well as superstructure responses can be effectively reduced using the proposed supervisory fuzzy control technique.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.629-633
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• 2004

The number of claims and disputes among project participants has been steadily increasing last a few years and it creates numerous conflicts and problems in the domestic construction industry. One of the root causes of claims and disputes can be explained by the fact that project objectives of participants are offer different and not aligned. This research is considered as a pre-study of developing a strategy to mitigate conflicts such as claims and disputes in the domestic construction industry by utilizing Alternative Dispute Resolution (ADR) techniques. This research focused on improving standard contrast documents to establish a systematic dispute resolution process which emphasize the ADR method. To do so, several well-recognized contract documents developed by FIDIC, AIA, ECC were throughly investigated and analyzed using a benchmarking process. Result of the research propose needs of improving the domestic construction document's some clauses and the details will be further Investigated through surveys and expert's opinions.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.7
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• pp.13-20
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• 2004

In order to set up the design of micro optical bench, optical coupling efficiencies of two sets of test benches are calculated. Simple linear connections of incoming and outgoing optical fibers with and without ball lenses are designed. Positional errors that are possible in actual fabrication processes we considered in the calculations and their tolerances are determined from -3 ㏈ conditions. For a simple fiber-to-fiber connection, the lateral misalignment should be limited to 2.7 um and tilt error 5.8o. In case of the fiber-to-fiber with ball lens, the working distance between fibers can be extended over 60 um. The optical coupling efficiency depends strongly on the positional errors of ball lenses along the optical axis, and it is also found that the lateral and vertical positional errors should be considered simultaneously in order to keep the high coupling efficiency.

• The Journal of the Korea Contents Association
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• v.20 no.2
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• pp.27-35
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• 2020

The Korean semiconductor industry is the top export item, and its technological prowess is also higher than that of its competitors. However, the technology gap with rivals will narrow. And the semiconductor industry is facing difficulties due to trade friction. Therefore, semiconductor firms should be more efficient in their production. we study analyzes the efficiency semiconductor firms using DEA model. We evaluate the CCR, BBC efficiency and RTS(return to scale) of 30 Korean semiconductor firms. There are a total of 13 efficient DMUs with a BCC of 1. There are a total of 6 efficient DMUs with a CCR of 1. A total of 10 DMUs were IRS in Scale Efficiency and a total of 9 DMUs were CRS in Scale Efficiency and a total of 11 DMUs were DRS in Scale Efficiency. We also suggest the semiconductor firms which can be benchmarked based on analyzed information.

• Journal of the Institute of Convergence Signal Processing
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• v.6 no.3
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• pp.148-156
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• 2005

The purpose of this paper is to propose an approach to design a robust servo controller based on the mixed $H_2/H_{\infty}$ theory, and confirm its validity by applying to a benchmark problem. First, the existing $H_{\infty}$ servo problem is modified to a structure for the mixed $H_2/H_{\infty}$ control problem by virtue of the internal model principle. By making use of proposed structure, we can divide specifications required in the robust servo system design into $H_2$ and $H_{\infty}$ performance criteria, respectively. It is shown that the proposed design approach is quite effective through an application to a three inertia benchmark problem.

• Journal of Internet Computing and Services
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• v.2 no.3
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• pp.81-92
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• 2001

The clustering environment with heterogeneous workstations provides the cost effectiveness and usability for executing applications in parallel. The load balancing is considered as a necessary feature for the clustering of heterogeneous workstations to minimize the turnaround time. Since each workstation may have different users, groups. requests for different tasks, and different processing power, the capability of each processing unit is relative to the others' unit in the clustering environment Previous works is a static approach which assign a predetermined weight for the processing capability of each workstation or a dynamic approach which executes a benchmark program to get relative processing capability of each workstation. The execution of the benchmark program, which has nothing to do with the application being executed, consumes the computation time and the overall turnaround time is delayed. In this paper, we present an efficient task distribution method and implementation of load balancing system for the clustering environment with heterogeneous workstations. Turnaround time of the methods presented in this paper is compared with the method without load balancing as well as with the method load balancing with performance evaluation program. The experimental results show that our methods outperform all the other methods that we compared.

• Korean Journal of Construction Engineering and Management
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• v.10 no.3
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• pp.122-129
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• 2009

Strategic planning is an essential function of senior management in any business firm. Planning involves the firm's behavior in an competitive market and adaptation of the company's resources towards the selected market strategy. This study presents a methodological procedure for strategic planning in global top-tier construction firms. This procedure consists of the following stages. First, analyzed growth of revenue in which weight of total construction firms' revenue shown in Global Top 225 Contractors(ENR). Second, analyzed specialty of construction products. The products are General Building, Power, Water Supply, Industrial/Petroleum Process, and Transportation. Third, analyzed business the portfolio plan. The business portfolio plan includes both local/overseas market and specification/diversification of construction products. It affects the subsequent choice of a benchmarking for development of each construction company. The choice of the benchmarking firm, among several available alternatives, should follow a careful analysis of the characteristics and benefits inherent in the implementation of each.

• Journal of the Korean Data and Information Science Society
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• v.25 no.5
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• pp.987-998
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• 2014

The primary purpose of this paper is to derive a benchmark dose lower limit (BMDL) of lead for the attention deficit/hyperactive disorder (ADHD) based on a longitudinal cohort data set which is referred to as CHEER data set. The CHEER data were recently recruited from the Ministry of Environment of S. Korea to investigate the effect of environment on children's health We first confirm the correlation of ADHD with the blood lead level using a linear mixed effect model. We report from the longitudinal characteristic of CHEER data that ADHD scores tend to have "regression to the mean". A dose-response curve of blood lead level with ADHD being the end point is derived and from this dose-response curve a few BMDLs are derived based on corresponding assumptions on the benchmark region.