• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.8
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• pp.42-50
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• 2013

The reactionary responses to control human standing dynamics were estimated under the assumption that postural complexity mainly occurs in the mid-sagittal plane. During the experiment, the subject was exposed to continuous horizontal perturbation. The ankle and hip joint rotations of the subject mainly contributed to maintaining standing postural control. The designed mobile platform generated anterior/posterior (AP) motion. Non-predictive random translation was used as input for the system. The mean acceleration generated by the platform was measured as $0.44m/s^2$. The measured data were analyzed in the frequency domain by the coherence function and the frequency response function to estimate its dynamic responses. The significant correlation found between the input and output of the postural control system. The frequency response function revealed prominent resonant peaks within its frequency spectrum and magnitude. Subjects behaved as a non-rigid two link inverted pendulum. The analyzed data are consistent with the outcome hypothesized for this study.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.445-449
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• 1989

Achievement of a straight line motion in the Cartesian space has a matter of great importance. Minimization of task execution time with linear interpolation in the joint space, accomplishing of a approximation of straight line motion in the Cartesian coordinate is considered as the prespecified task. Such determination yields minimum time joint-trajectory subject to input torque constraints. The applications of these results for joint-trajectory planning of a two-link manipulator with revolute joints are demonstrated by computer simulations.

• Tuberculosis and Respiratory Diseases
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• v.65 no.4
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• pp.261-268
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• 2008

The role of atypical bacterial infection in the pathogenesis of asthma is a subject of continuing debate. There is an increasing body of literature concerning the association between the atypical bacteria such as Mycoplasma pneumoniae (M. pneumoniae) and asthma pathogenesis. Moreover, many studies investigating such a link have been uncontrolled and have provided conflicting evidence, in part due to the difficulty in accurately diagnosing infection with these atypical pathogens. This manuscript will review the relationship between M. pneumoniae infection and asthma pathogenesis.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.2
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• pp.447-460
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• 1996

Network optimization and design procedures often separate quality of service (QOS) performance measures from reliability issues. This paper considers channel allocation and flow assignment (routing) in a network subject to link failures. Fault-tolerant channel allocation and flow assingments are determined which minimize network cost while maintaining QOS performance requirements. this approach is shown to yield significant network cost reductions compared to previous heuristic methods used in the design of packet switched network with unreliable links.

• Journal of the Korean Society for information Management
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• v.27 no.3
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• pp.83-102
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• 2010

This study aims to understand and compare the characteristics of two major approaches to solving global environmental problems - an academic approach including scholarly activities of environmental sciences and a practical approach of environmental movements led by NGOs - by employing informetric analysis methods. Knowledge structure of environmental sciences is depicted through co-citation networks of subject categories assigned to the cited journals in the discipline of environmental sciences for the 10-year period from 2000 to 2009. Furthermore, major interests of environmental NGOs are identified on the basis of external link data collected from web sites of the NGOs. Co-word analyses are also performed using the texts of journal papers in environmental sciences as well as news articles provided by NGO sites. Through the analyses, dominant subject areas of environmental sciences and environmental movements are identified demonstrating similarities and differences between the two approaches.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.2
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• pp.54-67
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• 2000

It is known that the performance of a DS-CDMA system mainly depends on Multiple Access Interference(MAI). The effect of MAI in a reverse link is larger than that of a forward link because of the absence of orthogonality among mobile stations. In this paper we investigate the effect of synchronous transmission in the reverse link, which is compared to the performance of asynchronous transmission in the reverse link. In addition, we consider the effect of interference from Mobile Stations(MSs) in a hand-over region. That is, if we assume that a MS is moving from a serving base station(sowing BS) to a target base station(target BS), the signal of the MS is not orthogonal with the signals of all other MSs within the target BS because the MS is only synchronized with the serving BS. Finally we suggest an interference cancellation scheme to reduce the interference from MSs in the region of hand-over, which can be one of solutions for the capacity degradation due to interference from the MSs in the hand-over region in reverse link synchronous transmission.

• Journal of The Korean Association For Science Education
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• v.38 no.4
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• pp.451-465
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• 2018

The purpose of this study is to investigate the challenges of pre-service teachers for good science teaching with focus on the process of imparting meaning of teaching subject. We have detailed research questions such as, 'What the pre-service teachers thought about teaching subject? How they grasped the meaning of the teaching subject? and What kinds of methods they have used to expose the meaning in their classes?'. We had four pre-service teachers who took the class 'Teaching methods in physics teaching' as voluntary participants in the first semester of 2017. The results show that there are common features in the process of imparting meaning of the teaching subject. The participants started to think about fundamental/existential answer to the question, 'Why should we teach science to students?'. In addition, they grasped the meaning of the teaching subject by using the specific key words. And they tried to link the teaching components with the teaching subject as the center. This challenging process led pre-service teachers to form teachers' identity and to enhance teacher professionalism.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37C no.11
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• pp.1129-1137
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• 2012

The wireless link of tactical datalink system provides a communication network to share digitalized tactical data in real-time. Also MAC(Multiple Access Control) of this system is subject to TDMA or CSMA according to a operated circumstance of target nodes to exchange the data reliably. In this paper, we verify the operability when we use CSMA scheme based on MIL-STD-188-220 in tactical datalink system which is basically designed with TDMA, and provide a mathematical analysis scheme to verify the operability and performance. Finally, by implementing CSMA scheme to a tactical datalink equipment we obtain practical results which can be compared with theoretical results.

• Journal of Communications and Networks
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• v.9 no.4
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• pp.394-401
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• 2007

High speed all optical network is a viable option to satisfy the exponential growth of internet usage in the recent years. Optical networks offer very high bit rates and, by employing technologies like internet protocol over wavelength division multiplexing(IP-over-WDM), these high bit rates can be effectively utilized. However, failure of a network component, carrying such high speed data traffic can result in enormous loss of data in a few seconds and persistence of a failure can severely degrade the performance of the entire network. Designing IP-over-WDM networks, which can withstand failures, has been subject of considerable interest in the research community recently. Most of the research is focused on the failure of optical links in the network. This paper addresses the problem of designing IP-over-WDM networks that do not suffer service degradation in case of a single link failure. The paper proposes an approach based on the framework provided by a recent paper by M. Kurant and P. Thiran. The proposed approach can be used to design large survivable IP-over-WDM networks.

• KIPS Transactions on Computer and Communication Systems
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• v.1 no.2
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• pp.103-108
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• 2012

Recently, IT Governance has been applied to business management environment. In this paper, we study business model that can minimize information security risk using IT governance in cloud computing environment. Especially, we propose the interaction model that link risk management for subject of information security governance. In our model, synergy means the effective, strategic and secure business support. And interaction analysis of BMIS's 4 elements and 6 dynamic interconnections is required. Therefore we propose interaction model which can link risk management based on COSO ERM or COBIT Risk IT Framework.