• The Korean Journal of Applied Statistics
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• v.23 no.5
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• pp.933-941
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• 2010

Biplot is a modern graphical methodology allowing for the projection of high-dimensional data to a low-dimensional subspace that is rich in information on variation in the data, correlation among variables as well as class separation. For the construction of biplots, we use a BiplotGUI package in a free statistical software R with increasing popularity. Moreover, using data from questionnaires given to Chonbuk National University freshmen in 2009, the relationship between career goals and career maturity are studied by applying the biplot method.

• Journal of Power System Engineering
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• v.16 no.4
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• pp.51-59
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• 2012

The computational flow analysis using LES technique was carried out to investigate the flow characteristics of a sirocco fan under the maximum flowrate condition. The commercial SC/Tetra software was used for this unsteady and three-dimensional numerical analysis. In consequence, because a flow is unstable within the range of about 50% of a housing depth from a bellmouth around the cutoff region, the passing flow through the blade cascade occurred on the X-Y plane is a slow or a reverse with approaching to the housing inlet. Also, the secondary flow shows on the radial plane of a housing, and its vortex center exists within about 33% of a housing depth from a bellmouth except the cutoff region. Moreover, the flow occurring on the exit plane of a sirocco fan shows a complex secondary flow.

• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.361-369
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• 1998

Recently, the improvement of on-board satellite sensors covering hyperspectral image sensors, high spatial resolution sensors provide data on earth in diverse aspect. The application field relating remotely sensed data also varies depending on what type of job one wants. The various resolution of sensors from low to extremely high is also available on the market with a user defined specific location. The expense to purchase remote sensed data is going down compare to the cost it need past few years ago in terms of research or private use. Now, the satellite remote sensed data is used on the field of forecasting, forestry, agriculture, urban reconstruction, geology, or other research field in order to extract meaningful information by applying special techniques of image processing. There are many image processing packages available worldwide and one common aspect is that they are expensive. There need to be a advanced satellite data processing package for people who can not afford commercial packages to apply special remote sensing techniques on their data and produce valued-added product. The study was carried out with the purpose of developing a special satellite data processing package which covers almost every satellite produced data with normal image processing functions and also special functions needed on specific research field with friendly graphical user interface (GUI). And for the people with any background of remote sensing with windows platform.

• Nuclear Engineering and Technology
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• v.51 no.8
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• pp.1916-1938
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• 2019

The objective of this paper is to discuss the modeling principles of phenomena governing core degradation/melting and in-vessel melt relocation during severe accidents in light water reactors. The proposed modeling approach has been applied in the development of a new accident simulation package, COMPASS (COre Meltdown Progression Accident Simulation Software). COMPASS can be used either as a stand-alone tool to simulate in-vessel meltdown progression up to and including RPV failure, or as a component of an integrated simulation package being developed in Korea for the APR1400 reactor. Interestingly, since the emphasis in the development of COMPASS modeling framework has been on capturing generic mechanistic aspects of accident progression in light water reactors, several parts of the overall model should be useful for future accident studies of other reactor designs, both PWRs and BWRs. The issues discussed in the paper include the overall structure of the model, the rationale behind the formulation of the governing equations and the associated simplifying assumptions, as well as the methodology used to verify both the physical and numerical consistencies of the overall solver. Furthermore, the results of COMPASS validation against two experimental data sets (CORA and PHEBUS) are shown, as well as of the predicted accident progression at TMI-2 reactor.

• Bulletin of the Society of Naval Architects of Korea
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• v.30 no.2
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• pp.44-52
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• 1993

선박에 있어서 철의장품은 종류와 수량이 다양하고 형상이 불규칙하여 대부분의 사업장에서 설계 전산화가 이루어지지 못하고 있는 실정이다. 의장설계실에서는 이를 전산화하기 위하여 먼저 철의장품의 표준을 제정 및 극대화하고 설계작업절차와 물량의 흐름을 전산과 연계하여 체계화 및 표준화하였다. 또한 선박의 전구역에 설치되는 철의장품들을 관련 양식과 함께 국제표준을 근거로 BASICA CADDS, SURFACE DESING, SDDP(structural Design ＆ Detailing Package) SOFTWARE를 이용하여 2차원(2-dimension) 및 3차원(3-dimension) 데이터베이스(database)화 하였으며 이를 POP-UP MENU를 이용, 쉽게 선택함으로써 모델링(modeling) 작업시수를 대폭 감소 시켰으며, 그래픽(graphic)에서 추출한 의장품의 데이터(data)를 의장품의 표준정보 FILE과 연계하여 라벨(LABEL) 및 치수(DIMENSION)를 기입하여 배치도를 추출하고 의장품의 제작, 설치, 계산 및 관리에 소요되는 설치도, 제작도 및 관련 보고서인 BOM(bill of material), PML(pallet material list), 의장제작품 LIST, COG(center of gravity), 관리점 등을 자동추출 및 관리전산망(PC-lan)과 연계할 수 있는 DECOM(철의장 전산설계 전용 package)을 89년에 개 발하여 의장설계에 적용하여 왔으며 ORACLE사의 RDBMS(relational database management system)를 도입하여 이를 보완하므로써 정보의 일관화 및 공유화가 가능하게 되었다. 그 결과 설계 M/H절감, 생산성 향상, 자재 및 관련 정보 전달에 혁신적인 변화 향상을 가져오게 되었다.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.67 no.2
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• pp.63-69
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• 2018

In this paper, the operation principle of a bi-directional switch type resonant AC link snubber circuit was described, together with the practical design procedure, which employs in the proposed power module bridge package type resonant AC link snubber. The novel prototype of power module bridge package type resonant AC link snubber-assisted voltage type sinewave soft switching PWM inverter using IGBT power module was demonstrated herein. It was verified that both the auxiliary power switches in this resonant AC link snubber circuit and the main power switches commutate under the condition of soft switching commutation principle. In addition, the power losses of the new soft switching inverter treated here were analyzed by implementing the experimental data of the IGBT and diode v-i characteristics in addition to switching power loss characteristics into our original computer simulation software developed by the authors. Then, the voltage type sinewave soft switching PWM inverter was high efficiency than that of hard switching PWM inverter, along with performance operation waveforms. In the future, the comparative feasibility study of power module bridge type resonant AC link snubber and its related soft switching inverter in addition to the other types resonant snubber assisted soft switching inverter should be done from a practical point of view.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.11
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• pp.1733-1740
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• 2010

The analysis of the dynamic behavior of the packaging of a drum washing machine has been carried out under the drop impact conditions. LS-DYNA software is used for performing the finite element analysis, and the validations are performed by comparing with the impact acceleration, effective stress and deformation of cushioned package with high-speed camera during free drop test. By analyzing the cushion characteristics and the design parameters of the original packaging, a packaging with an improved design is developed, and this design is validated on the basis of the results of the distribution test which consists of drop test, vibration test, stacking test, squeez test and so on. The drop impact simulation and analysis methods developed in this study can be adopted to successfully improve the cushioning provided by the packaging and to reduce the cost involved in developing new packaging for drum washing machines.

• Communications for Statistical Applications and Methods
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• v.29 no.4
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• pp.421-439
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• 2022

Phase I dose-finding trials are essential in drug development. By finding the maximum tolerated dose (MTD) of a new drug or treatment, a Phase I trial establishes the recommended doses for later-phase testing. The primary toxicity endpoint of interest is often a binary variable, which describes an event of a patient who experiences dose-limiting toxicity. However, there is a growing interest in dose-finding studies regarding non-binary outcomes, defined by either the weighted sum of rates of various toxicity grades or a continuous outcome. Although several novel methods have been proposed in the literature, accessible software is still lacking to implement these methods. This study introduces a newly developed R package, UnifiedDoseFinding, which implements three phase I dose-finding methods with non-binary outcomes (Quasi- and Robust Quasi-CRM designs by Yuan et al. (2007) and Pan et al. (2014), gBOIN design by Mu et al. (2019), and by a method by Ivanova and Kim (2009)). For each of the methods, UnifiedDoseFinding provides corresponding functions that begin with next that determines the dose for the next cohort of patients, select, which selects the MTD defined by the non-binary toxicity endpoint when the trial is completed, and get oc, which obtains the operating characteristics. Three real examples are provided to help practitioners use these methods. The R package UnifiedDoseFinding, which is accessible in R CRAN, provides a user-friendly tool to facilitate the implementation of innovative dose-finding studies with nonbinary outcomes.

• Imaging Science in Dentistry
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• v.47 no.2
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• pp.75-86
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• 2017

Purpose: The purpose of this study was to apply a newly developed free software program, at low cost and with minimal time, to evaluate the quality of dental and maxillofacial cone-beam computed tomography (CBCT) images. Materials and Methods: A polymethyl methacrylate (PMMA) phantom, CQP-IFBA, was scanned in 3 CBCT units with 7 protocols. A macro program was developed, using the free software ImageJ, to automatically evaluate the image quality parameters. The image quality evaluation was based on 8 parameters: uniformity, the signal-to-noise ratio (SNR), noise, the contrast-to-noise ratio (CNR), spatial resolution, the artifact index, geometric accuracy, and low-contrast resolution. Results: The image uniformity and noise depended on the protocol that was applied. Regarding the CNR, high-density structures were more sensitive to the effect of scanning parameters. There were no significant differences between SNR and CNR in centered and peripheral objects. The geometric accuracy assessment showed that all the distance measurements were lower than the real values. Low-contrast resolution was influenced by the scanning parameters, and the 1-mm rod present in the phantom was not depicted in any of the 3 CBCT units. Smaller voxel sizes presented higher spatial resolution. There were no significant differences among the protocols regarding artifact presence. Conclusion: This software package provided a fast, low-cost, and feasible method for the evaluation of image quality parameters in CBCT.

• The Journal of the Korea Contents Association
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• v.5 no.1
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• pp.9-17
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• 2005

In this paper we developed e-Leaning system based on open source software. We selected the Moodle that after compared the open source learning management systems. Moodle is LAMP(Linux, Apache, MySQL, PHP) based course management system (CMS), a software package designed to help educators create quality online courses. One of the main advantages of Moodle over other systems is a strong grounding in social constructionist pedagogy. Also we integrated Moodle and legacy systems such as streaming service, webhard service, and short message service. The system operated during one semester at college using blended learning model. We had obtained showed that the students had almost all scored quite highly as preferred learning environment through COLLES(Constructivist On-Line Learning Environment Survey) and ATTLS(Attitudes to Thinking and Learning Survey). Therefore this research showed that open source based e-Loaming system is stable and possible.