• 디지털산업정보학회논문지
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• 제12권2호
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• pp.87-102
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• 2016

The customer requirements are constantly changing in the hyper-competition and competition is becoming increasingly intensified. In order to ensure the competitive advantage in the industry should focus on the management activities to enhance customer satisfaction. High quality means pleasing customers, not just protecting them from annoyances. It is due to continuous and requires the establishment of a quality management system that meets the characteristics and systematization need to manage a stable quality and productivity, which should be done in a company-wide quality management activities. The purpose of this study is to identify a suitable organizational diagnostic model for considering to adopt ISO 9001 quality management systems. We used the three-round delphi techniques on a panel of 30 experts. A total of 26 assessment indicators were developed through this panel. First, it is important to evaluate the strategy about quality. Second, it is important to evaluate the systems about periodically communicating quality agenda. Third, it is important to evaluate the responsibility of overall business process. In conclusion, this study empirically shows how firms can develop an organizational diagnostic model to increase their quality management systems.

• 소성∙가공
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• 제21권8호
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• pp.499-505
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• 2012

The fuel cell is a very promising power generation system combining the benefits of extremely low emissions, high efficiency, ease of maintenance and durability. In order to promote the commercialization of fuel cells, a flexible forming process, in which a hyper-elastic rubber is adopted as a medium to transmit forming pressure, is suggested as an efficient and cost effective manufacturing method for fuel cell bipolar plates. In this study, the ability of this flexible forming process to produce the micro channel arrays on metallic bipolar plates was first demonstrated experimentally. Then, a finite element (FE) model was built and validated through comparisons between simulated and experimental results. The effects of key process parameters on the forming performance such as applied load and punch velocity were investigated. As a result, appropriate process parameter values allowing high dimensional accuracy without failure were suggested.

• 소성∙가공
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• 제29권4호
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• pp.218-228
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• 2020

The prediction of final mass and optimized process conditions of injection molded products using Artificial Neural Network (ANN) were demonstrated. The ANN was modeled with 10 input parameters and one output parameter (mass). The input parameters, i.e.; melt temperature, mold temperature, injection speed, packing pressure, packing time, cooling time, back pressure, plastification speed, V/P switchover, and suck back were selected. To generate training data for the ANN model, 77 experiments based on the combination of orthogonal sampling and random sampling were performed. The collected training data were normalized to eliminate scale differences between factors to improve the prediction performance of the ANN model. Grid search and random search method were used to find the optimized hyper-parameter of the ANN model. After the training of ANN model, optimized process conditions that satisfied the target mass of 41.14 g were predicted. The predicted process conditions were verified through actual injection molding experiments. Through the verification, it was found that the average deviation in the optimized conditions was 0.15±0.07 g. This value confirms that our proposed procedure can successfully predict the optimized process conditions for the target mass of injection molded products.

• Journal of Welding and Joining
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• 제17권4호
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• pp.26-31
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• 1999

An attempt was made in this study to investigate the brazing characteristics of Zr-Be binary amorphous alloys for the development of a new brazing filler metal for joining Zircaloy-4 nuclear fuel cladding tubes. This study was also aimed at the feasibility study of rapidly solidified amorphous alloys to substitute the conventional physical vapor-deposited(PVD) metallic beryllium. The $Zr_{1-x}Be_{x}$($0.3\leq$x$\leq0.5$) binary amorphous alloys were produced in the ribbon form by the melt-spinning method. It was confirmed by x-ray diffraction that the ribbons were amorphous. The amorphous. the amorphous alloys were used to join bearing pads on Zircaloy-4 nuclear fuel cladding tubes. Using Zr-Be amorphous alloys as filler metals, it was found that the reduction in the tube wall thickness caused by erosion was prevented. Especially, in the case of using $Zr_{0.65}Be_{0.35}$ and $Zr_{0.7}Be_{0.3}$ amorphousalloys, the smooth and spherical primary $\alpha$-Zr particles appeared in the brazed layer, which was the most desirable microstructure from the corrosion-resistance standpoint.

• 공업화학
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• 제21권5호
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• pp.586-589
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• 2010

본 연구에서는 1,3-dicarbonyl 화합물과 올레핀 화합물의 산화첨가반응에서 $Ag_2CO_3$/celite (SC)를 촉매로 하여 1,3-cycleohexandion (1,3-CHD)과 ethyl vinyl ether (EVE)를 acetonitrile (AN), dimethyl sulfoxide (DMSO), benzene (BZ), heptane (HT)을 각각 용매로 하여 반응을 진행시켜 보았다. 그 결과 수득률이 78, 40, 15, 10%로 나타났다. 따라서 이러한 용매의 효과에 따른 수득률의 변화를 알아보기 위하여 하이퍼캠의 반경험적 방법으로 PM3와 ZINDO/1 파라미터를 이용하여 이론적 고찰을 해 보았다.

• 대한후두음성언어의학회지
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• 제8권2호
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• pp.210-216
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• 1997

Many tools have been used to evaluate the voice abnormalities of velopharyngeal insufficiency(VPI). The aim of study was to obtain the objective evaluation method of VPI by comparing the acoustic and nasalance data of experimentally induced VPI group and those of normal control group. Ten healthy young men were included in this study Mild and severe VPI were experimentally induced by retracting velopharyngeal movement. Using the nasometer, we obtained the nasalance score of the sustained oral vowels and those of three types of nasometer passages and the slope scores of nasogram of nasal words. And we analysed the change of formant frequencies for the sustained oral vowels and the changes of various parameters of hyper-tnasality by the computerized speech analysis system. The nasalance score of sustained /a/ was increased significantly in VPI conditions. There was no changes in the slope score of nasogram. On the acoustic speech analysis, the second formant frequencies of vowel /e/ and /i/ were decreased significantly in VPI conditions. This results suggested that the measurement of nasalance score and formant frequency might be useful in the evaluation of VPI.

• 디지털산업정보학회논문지
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• 제16권3호
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• pp.37-47
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• 2020

The In the 4^th industrial revolution, cyber space will evolve into hyper-connectivity, super-convergence, and super-intelligence due to the development of advanced information and communication technologies, which will connect the nation's core infrastructure into a single network. As applying the 4^th industrial revolution technology to the cyber attack technique, it is evolving in an intelligent and sophisticate method. In order to response intelligent cyber attacks, it is difficult to guarantee self-defense in cyberspace by policy-oriented, preplanned-centric and hierarchical cyber response strategies. Therefore, this research aims to propose a situation-flexible & action-oriented cyber response mechanism that can respond flexibly by selecting the most optimal smart security solution according to changes in the cyber attack steps. The proposed cyber response mechanism operates the smart security solutions according to the action-oriented detailed strategies. In addition, artificial intelligence-based decision-making systems are used to select the smart security technology with the best responsiveness.

• 대한화학회지
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• 제40권5호
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• pp.317-326
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• 1996

Linear polyenes, ($C_4H_6\;to\;C_{30}H_{32}$)의 frequency dependent longitudinal polarizablilty, ${\alpha}zz(\omega)$ 와 second hyperpolarizabilities, ${\gamma}zzzz(\omega)$를 6-31G basis set에서 ab initio TDHF 이론을 사용하여 계산하였다. 폴리 아세틸렌의 frequency dispersion effect를 보기 위하여 외부 전기장의 주파수 영역에 광학성질을 구한후 무한 사슬을 갖는 고분자에 대하여 extrapolate하였다. 이때걸어준 외부 전기장에서의 광학적 성질에 대한 static field 에서의 광학성질의 비를 사용하여 비공면 영역에서의 dispersion effect를 고찰하였다. 또한 광학성질에 대한 주변 사슬의 효과를 조사하였으며 공명이 일어나는 영역에서의 광학 성질을 계산하기 위한 이론적 방법을 제안하였다.

• 한국세라믹학회지
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• 제43권10호
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• pp.646-652
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• 2006

Several oxynitride glasses were fabricated by means of adding $Si_3N_4$ powders as nitrogen source to Ca-Al-Si-O-N (CAS) and Mg-Al-Si-O-N (MAS) glass powders, and heat-treated in graphite crucible at 1600$^{\circ}C$ for 1 h. The physical and mechanical properties as well as impact resistance were generally increased and compared with each other. The impact resistance properties of those manufactured glasses were evaluated by DOP (depth of penetration) method which is a way to analyze armor materials. There were two means to be used herein; the copper jet impacted at hyper velocity by exploding K2l5 warhead and tungsten heavy alloy (WHA) impact bar at high velocity by firing in 30 mm solid propellent gun. The impact resistance properties against copper jet were increased and then decreased with increasing nitrogen content, while those against WHA bar were not changed apparently with nitrogen content.

• 복식
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• 제59권8호
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• pp.152-165
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• 2009

The purpose of this study was to expand the expression of Fashion Illustration using Lenticular imaging process. In the 2-dimensional pictures, Lenticular imaging process can be effective to make multiple, virtual and variable images, which are assumed the main characteristics of modern Fashion Illustration. For this study, the main characteristics of digital based fashion trend and Fashion Illustration were analyzed. The main characteristics of digital based fashion were 'Interaction, Variableness, Virtuality, Multiples and Hyper-text' which were related with Simulacre thinking. The main characteristics of expression in Fashion Illustration were 'Virtuality and Multiples'. The image of 'Variableness' was an important factor in digital based fashion, but it was restricted within Fashion Illustration because of the 2-dimensional picture. Therefore, the Lenticular imaging process was proposed as an effective method to expand 2-dimensional limit, giving an effect of 'Variableness' in Fashion Illustration. Based on this study, 5 illustration works were proposed. The Lenticular imaging process was applied in making the images of 'Virtuality, Multiples and Variableness' in 5 works. The result of this study can be a basic material to understand the characteristics of modern Fashion Illustration as a meaningful sub-culture, and diverse expressions corresponding with the phases of the times.