• Journal of Navigation and Port Research
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• v.35 no.8
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• pp.619-624
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• 2011

A significant factor limiting the ranging accuracy of Loran (Long Range Navigation) signal is the additional secondary factor (ASF) in the time of arrival (TOA) measurements. Precise ASF values are essential if Loran deliver the high absolute accuracies demanded for aircraft approach, maritime harbour entrance. We measured the absolute propagation delay between Pohang Loran signal and Loran receiver output signal by comparing with Cesium atomic clock. In this study we measured ASFs between Pohang 9930M station and the 12 measurement points in the Yeongil Bay by using the measurement technique of absolute time delay. The measurement points were spaced at interval of 3 km by 3 km. An E-field antenna and an H-field antenna were used to improve the accuracy of ASF measurements and a DGPS (Differential GPS) receiver was used for accurate positions. We have gotten the result that the measured ASFs were compared with the predicted ASFs through this measurement technique.

• Archives of design research
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• v.14 no.2
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• pp.267-278
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• 2001

Beyond the simple stage of technical development, the growth of information networks have changed areas such as the economy, communities, and education. Existing knowledge and new knowledge about these things have developed and either coexist or conflict with each other. It is difficult to predict the result of this interaction since old and new information is changing so quickly. The transition from a simple communication to an interactive communication is related to a changed communication environment which involves a more complex level of understanding. Establishing the new design concept which is aimed at the future and developing new educational programs which respond to these new information networks are important in order to educate designers who can adjust to the new information network era and construct design education. This paper reports research about the process of developing new education systems that explore the new design paradigms, the changing information network, and the proper approaches to developing design education programs which fulfill these requirements.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.11
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• pp.951-956
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• 2008

The high temperature creep properties of the generating plant's high temperature tube, pipe and header and such are very significant in accordance with long-time exposure to the high temperature and pressure environment. Not only this, but as the welding procedure is compulsory for the cohesion of components, the creep properties regarding the local microstructures of steel weldment are very important. In order to understand the creep properties regarding the local microstructures of steel weldment, the SP-Creep test which is easy to get sample from the field component was conducted. The local microstructure of steel weldment, that is, W.M. and B.M.'s microstructures were observed using the SEM. The rupture time of W.M. was longer as 110 % averagely in a same condition, which is the consequence of the difference of the microstructure. Each lethargy coefficient of B.M. and W.M. is evaluated by the relation among the temperature, load and the rupture time from SP-Creep Test. The life estimation equation can be induced by the transformation of Power-law. B.M. and W.M. for each $550\;^{\circ}C$ and $575\;^{\circ}C$, the very similar to normal temperature of the domestic thermal power generation in working, are estimated.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.2101-2108
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• 2008

Most of train fires which occur in usual cases do not grow up significantly on a large scale enough to bring about casualties and harmful damages. However, the consequence of some train fire accidents can be devastating disaster so that it would be even recorded in history in unusual cases. Accordingly, such a probability of fire disaster cannot be ignored in aspect of the railway safety assesment. A scale of injury and damage is very difficult to predict and analyze. Because it is depend on various factors, i.e. fire load, burning period, facilities, environment condition, and so on. Thus, a prediction of fire load could be understood as a one methodology to estimate railway safety assesment. The summation method which is one of them is used to evaluate the overall fire load by assuming that sum of heat release rate per unit area or mass of each composite material equals the total. However, since the train fire is classified into a compartment fire in under-ventilation condition. The summation method do not estimate a fire load completely. In this journal, Various methods to predict fire load are introduced and evaluated. Especially the fire simulation tool FDS(Fire Dynamics Simulator)which is based on the CFD(Computational Fluid Dynamics) is introduced, too. Through the FDS simulation, numerical analyses for the fire load and flame spread are performed. Then, these results of the simulation are validated through the comparison study with the experimental data. Then, limitations and approximations including in simulation process are discussed. The future direction of research is proposed.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2017.11a
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• pp.1581-1603
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• 2017

한국의 기초연구는 1977년 한국과학재단(현(現) 한국연구재단) 설립을 시작으로 1989년 기초과학진흥 원년 선포, 기초과학진흥법 제정을 통해 정부의 과감한 연구비 투자와 과학기술 인력양성 등에 힘입어 놀라운 속도로 성장하였다. 그러나 정부 R&D 투자가 증가하였음에도 불구하고 대학 연구자의 낮은 정부 기초연구비 수혜 체감율 이슈가 지속적으로 제기되었다. 본 연구는 기초연구의 정의와 역할에 관한 근본적인 질문에 대한 답을 찾고 그간의 투자와 성과 등에 대한 분석을 기반으로 한 합리적 진단을 통해 미래를 위한 발전과제를 제안하고자 하였다. 이를 위해 한국의 기초연구투자 현황과 수준 등을 분석하여 우리의 기초연구가 다음 단계로 도약하기 위해 필요한 여섯 가지 핵심이슈별 진단을 내리고자 하였다. 핵심이슈는 대학에 대한 기초연구 투자 규모, 교수 1인당 적정 지원 규모, 기초연구비 지원 방식, 연구과제 선정률의 적정선 유지, 우수 연구자의 체계적 지원, 연구몰입환경 조성이다. 다각적 분석과 진단을 기반으로 기초연구의 지속적 혁신을 위한 다섯 가지 발전과제를 제안하였다. 발전과제는 대학연구비 증액, 기초연구 펀딩방식 다양화, 연구분야별 연구지원체계 구축 및 예측 가능한 원칙 수립, 우수연구자에 대한 안정적이고 충분한 지원, 연구행정 부담 완화이다. 정책적 제도적 발전과제 외에 기초연구를 통한 직접적인 경제 사회 문화적 효과를 강조하기 보다는 창의적 도전적인 연구 수행 과정을 통해 축적되는 고유의 경험과 지식을 기반으로 세계를 선도하는 연구가 창출될 수 있음을 우리 모두가 받아들일 수 있는 문화조성이 더불어 필요할 것이다.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.7
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• pp.957-963
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• 2007

In this paper, Nonlinear Autoregressive (NAR) method based on Least Square-Support Vector Regression (LS-SVR) is introduced and tested for nonlinear sustained vowel modeling. In the database of total 43 sustained vowel of Benign Vocal Fold Lesions having aperiodic waveform, this nonlinear synthesizer near perfectly reproduced chaotic sustained vowels, and also conserved the naturalness of sound such as jitter, compared to Linear Predictive Coding does not keep these naturalness. However, the results of some phonation are quite different from the original sounds. These results are assumed that single-band model can not afford to control and decompose the high frequency components. Therefore multi-band model with wavelet filterbank is adopted for substituting single band model. As a results, multi-band model results in improved stability. Finally, nonlinear sustained vowel modeling using NAR based on LS-SVR can successfully reconstruct synthesized sounds nearly similar to original voiced sounds.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.39 no.4
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• pp.329-335
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• 2013

Three-dimensional quantitative structure-activity relationships (3D-QSARs) models between the substituents with changing groups ($R_1$ & $R_2$) of 4-hydroxybenzyl alcohol (4-HBA) derivatives as substrate molecule and their inhibitory activities against tyrosinase were derived and discussed quantitatively. The optimized CoMSIA FF model showed the best predictability and fitness ($r^2$ = 0.858 & $q^2$ = 0.951). The contour maps of the optimized CoMSIA FF model showed that, the inhibitory activities of the analogues against tyrosinase were expected to increase when hydrophobic (Hy) favor, negative charge (E) favor, steric (S) disfavor and hydrogen bond donor (HD) disfavor groups were substituted at the $R_2$ position. When the hydrogen bond donor (HD) favor groups were substituted at the $R_1$ position, it is predicted that the substituents will be able to increase the inhibitory activity.

• Magazine of the Korea Concrete Institute
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• v.9 no.2
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• pp.121-132
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• 1997

The thermal behavior of' concrete can be ch;lracterized from a knowledge of concrete ternperatu1.e at early ages, environmental conditions, and cement hydration in the mixture. 'l'o account for thost. interactions, a computer model was developed for prwlicting the temperature pr.ol'ile in hnrdcning c o n c r c t ~ st.r~icture in terms of material and tmvironmcntal factors. The cerncnt hydration cha~.acteristics such as the activating energy, total heat 1ihei.atr.d. anti th\ulcorner degree of' hydration. can represent the internal heat gc,neration. In this study. th(> activating c1ncrgy and the tlcgree of' hydration curve were determined well fmm the rnortn~. compressive strength tests while total amount of heat liberated was determined by tht> isothermal calorimctcr method. The main purpose of' this study is to correlate measured tt>mperaturr distributions in a concrete st1,ucture during thc hardening process with the ~ c s u l t s computed f'ro~n theoretical considrl.ations. Using twodimensional heat transfer model, first. the importance of several parameters will be identified by a parametric analysis. Then, the tcmpcmture distribution of thc cylindrical concrete specimen in the laboratory was mensuwti and compared with that yielded by thc theoretical considel.ations.

• Journal of Convergence for Information Technology
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• v.8 no.2
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• pp.141-148
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• 2018

The purpose of this paper is to explore the scope of realization of multiple perspectives so that the implementation of the right to be forgotten is more realistic than the ideal information deletion concept. We examined domestic and foreign legal system and technology/service trends, and reflected the classification realization level of service realization, processing type and information characteristics of personal information processor, and legislative/technical factors for multi-level scope analysis. As a result, we have presented a matrix of the range of realization of the right to be forgotten and the scope of diversified regulation by the subject of protection. This study will be extended to the convergence of law and engineering, and will contribute to the prediction of social costs and expansion of the market by identifying the scope of 'deletion rights'.

• Aerospace Engineering and Technology
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• v.10 no.2
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• pp.29-36
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• 2011

The Science and Technology Satellite-3 (STSAT-3) is based on the KITSAT-1, 2, 3 and STSAT-1, 2 which were Korea micro-satellites for the mission of space and earth science. The objectives of the STSAT-3 are to support earth and space sciences in parallel with the demonstration of spacecraft technology. The STSAT-3 carries an infrared (IR) camera for space & earth observation and an imaging spectrometer for earth observation. The IR payload instrument of the STSAT-3, Multi-purpose Infrared Imaging System (MIRIS), will observe the Galactic plane and North/South Ecliptic poles to research the origin of universe. The secondary payload instrument, Compact Imaging Spectrometer (COMIS), images the Earth's surface. The data acquired from COMIS are expected to be used for various application fields such as monitoring of disaster management, water quality studies, and farmland assessment. In this paper we present the operations concept of STSAT-3 which will be launched into a sun-synchronous orbit at a nominal altitude of 600km in late 2012.