• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.24.1-24
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• 1996

The development of future aircraft that involves the expanded flight envelop will place increased performance requirements on the design of the flight control system. Maneuvering areas are expanding into flight envelopes characterized by significantly larger levels of modeling uncertainty than encountered in present flight control designs. Conventional flight control techniques that ignore the effects of large parameter variations, modeling uncertainties and nonlinearities, will likely produce designs with poor performance and robustness. Recent advances in modern control theories called advanced control theories, most notably the H$\_$.inf./ synthesis technique, adaptive control and neural network application, offer the promise of a design technique that can produce both high performance and robust controllers for next generation aircraft. This special lecture will survey the recent development in advanced flight control and review the possible application of advanced control theories.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.454-459
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• 2004

This paper considers the problem of satellite's orbit control and a solution based in Linear Matrix Inequalities (LMI) is proposed for the case of Low Earth Orbiters (LEO). In particular, the modelling procedure and the algorithm for control law synthesis are tested using as study case the European Gravity Field and Ocean Circulation Explorer satellite (GOCE), to be launched by the European Space Agency (ESA) in the year 2006. The scientific objective of this space mission is the recovering of the Earth gravity field with high accuracy (less than 10${\mu}m$/${\mu}m$) and spatial resolution (better than 100km). In order to meet these scientific requirements, the orbit control must guarantee stringent specifications in terms of environmental disturbances attenuation (atmospheric drag forces) even in presence of high levels of model uncertainty.

• Journal of Astronomy and Space Sciences
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• v.23 no.2
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• pp.91-96
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• 2006

We use near-infrared observations of eight selected Galactic globular clusters to estimate their distances by comparing the observed and theoretically predicted K magnitudes of the red giant branch bumps and tips. The K magnitude levels of the RGB bump and tip have been measured from the luminosity function of the selected RGB stars in the clusters. Theoretical absolute $M_k$ magnitudes of the RGB bump and tip are taken from the Yonsei-Yale isochrones. Comparing the observed apparent K magnitude with the derived absolute $M_k$ magnitude, we calculate the distance moduli of the clusters. We discuss the dependency of the derived distance modulus on the cluster age and the uncertainty of the distance measurement from the near-infrared photometry of the RGB bump and tip.

• KIEAE Journal
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• v.10 no.3
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• pp.3-10
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• 2010

As indoor air quality directly affects health and comforts of the residents, researchers from different countries have continued to explore criteria by which indoor air quality can be indicated in a scientific and quantitative manner over the past several decades. However, there are many possibilities that can deteriorate indoor air quality. Due to the uncertainty of influence factors, it is quite difficult to develop a correct evaluation model and quantitative method. Furthermore, the effects from the indoor air pollutants have different levels, leading to the difficulties to apply the regular standard. This study aims to propose evaluation criteria by using the FD-AHP analysis. Obtained findings will be beneficial to construct apartment buildings, commercial buildings and others health performance evaluation framework.

• Journal of The Korean Association For Science Education
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• v.11 no.1
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• pp.25-36
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• 1991

For the purpose of extending the fields of biological preconceptual studies, the conceptions of plant classification, which have not been researched on them in korea, were selected and a questionnaire were administered to a sample of a total of 965 students at elementary and secondary school levels of korea. Many elementary school students have the alternative conceptions that plants are not alive. The misconceptions in plant classification are partly caused by the uncertainty of biological terms. To serve the teachers, who have difficulty in teaching them, the preceeding results are summarised with Composition the misconception maps.

• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1391-1394
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• 2008

Polymer materials are very difficult to decompose for the purpose of chemical analysis. Nondestructive analysis without pretreatment provides a suitable solution that will overcome this obstacle. In this study, CRM candidate samples that contained toxic elements such as As, Cd, Cr and Zn in a polypropylene (PP) were analyzed using instrumental neutron activation analysis (INAA). The analytical results were obtained from ten samples selected by random sampling at two different concentration levels (low and high). Particular attention was paid to reducing analytical errors and evaluating the associated uncertainty.

• Korean Management Science Review
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• v.30 no.1
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• pp.149-165
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• 2013

This study empirically investigated the changes of performance evaluation systems under the environment of supply-chain e-commerce. The objectives of e-commerce include obtaining financial profit, internal innovation through processes integration, learning with information flow, and customer satisfaction through quick response. These objectives are generally consistent with the four evaluation measures of balanced scorecard(BSC). This study, first, demonstrated that perceived environmental uncertainty(PEU) has a significant effect on the adoptions of e-commerce and BSC, and severe competition positively influences the use of e-commerce. With cluster analysis and subgroup analysis, we also showed that under the high adoption levels of e-commerce, the high utilization of BSC can improve the supply-chain performance of a firm. In addition, it was found that the use of e-commerce indirectly and significantly affects supply-chain performance through inter-organizational information flow, and the supply-chain performance of a firm leads to the improvement of organizational performance.

• Korean Medical Education Review
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• v.19 no.3
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• pp.152-157
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• 2017

Interprofessional education (IPE) fosters effective team-based collaborative practice among members of different health care professions to advance high-quality and safe patient care. Although the importance of IPE has been recognized and IPE initiatives have expanded rapidly in the past decades, substantial difficulties in IPE assessment still exist. At present, a lack of consensus on the optimal approach to IPE assessment contributes to uncertainty about the level of attainment of collaborative team performance. This paper aims to provide an overview of the benefits and current challenges associated with IPE assessment. Furthermore, a multifactor model with an assessment matrix and assessment blueprints from a recent study is briefly discussed. We also provide examples of assessment blueprints for the team management of stroke patient discharge covering a competency examination at the levels of individuals, the team, and the task.

• Structural Engineering and Mechanics
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• v.23 no.2
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• pp.195-207
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• 2006

An efficient and accurate algorithm is proposed to estimate cable safety factor of suspension bridges satisfying prescribed reliability levels. Uncertainties in the structure and load parameters are incorporated. The proposed algorithm integrates the concepts of the inverse reliability method and deterministic method for assessing cable safety factors of suspension bridges. The unique feature of the proposed method is that it offers a tool for cable safety assessment of suspension bridges, when the reliability level is specified as a target to be satisfied by the designer. After the accuracy and efficiency of the method are demonstrated through two numerical examples, the method is used to estimate cable safety factors of suspension bridges with span length ranging from 2000 to 5000 m. The results show that the deterministic method overestimates cable safety factor of suspension bridges because of neglecting the parameter uncertainty effects. The actual cable safety factor of suspension bridges should be estimated based on the proposed method.

• Bulletin of the Korean Chemical Society
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• v.10 no.1
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• pp.30-32
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• 1989

Traces of nine elements, gold, arsenic, cobalt, chromium, copper, europium, hafnium, sodium and antimony in commercially available silicon crystals were determined by the instrumental neutron activation analysis using the single comparator method. The values of the concentrations of these elements in both single and polycrystals were found to decrease significantly to a low limiting level by simply washing and etching surface contaminants having been introduced during various steps of sample preparation and irradiation. However, the chromium levels in polycrystals were not easily decreased, these depending upon the cutting tools employed. The Sb-doped content in each semiconductor has been compared with the associated quantities such as the concentration and the conductivity range given by the sample donor. Uncertainty in the sodium analysis due to the fission neutron reaction by silicon itself was discussed.