• Transactions of Materials Processing
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• v.31 no.4
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• pp.186-193
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• 2022

The application of UHSS sheet is being expanded up to 50% to reduce the weight of automobiles and improve safety. However, due to the high strength and low elongation of the ultra-high tensile strength steel sheet, product defects such as spring back and mold defects such as cracks and chippings also occur. In this study, Pin/Ring on Disc and Spiral wear tests were conducted to evaluate the durability of Ti/Cr-coated molds for forming 1.2GPa grade UHSS sheets. Component analysis and thickness were measured for each coating layer, and hardness and adhesion were investigated to determine mechanical properties. Combining the results of various wear tests, it was found that the TiAlN coating had the best wear and sticking resistance.

• International journal of advanced smart convergence
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• v.12 no.3
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• pp.163-167
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• 2023

The restaurant industry is an industry with low entry barriers, and furthermore, it is an indispensable industry in life. However, for the restaurant industry, it is necessary to start a business considering many factors. In particular, the comparative group for each restaurant industry is different, and the commercial area analysis should be analyzed differently. Moreover, counseling for restaurant start-ups is still sticking to how to start a restaurant by meeting with each franchise supervisor or counselor. Therefore, a restaurant start-up chatbot is needed for prospective restaurant founders, and a food tech chatbot is needed to collect basic data. Therefore, in this study, factors for restaurant start-ups were divided into youth, preliminary start-ups, menus, taste, and food. In the case of restaurant start-ups with low entry barriers, it was confirmed as the most preferred start-up by young people. However, indiscriminate restaurant start-ups not only increase the closing rate but also have a significant impact on household debt, so accurate consulting should be used to lower the closing rate and increase the success rate. Furthermore, theories and measures for food technologies such as chatbots should be further developed to obtain accurate information on franchise start-ups.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.147-150
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• 2008

The explanation of Tourism Guide of present whole country main tourist resort helps to understand the tourist resort. However, activity space of Tourism Guide is not state that can be understood all by upbringing by a natural voice. Because action of Tourism Guide is much in case of most sightseeing explanation to use microphone and speaker etc., as sticking that attach and uses to clothing and so on uses, there are much vexatious. Treatise that see hereupon makes use of establishment style fixing microphone and embody inputted obscene sounds by On-board system inflecting MCU (ATmega128), MSM7731-02 Oki-Dual Codec to minimize noise using ecad filter, and embodied a control program by serial communication method with filter codec. The resultant audible direction the maximum 59ms, the line echo maximum 27ms, the echo decrease maximum 35dB, it embodied the system which removes the adaptation elder brother noise of the back.

• Journal of the Korean Society of Clothing and Textiles
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• v.12 no.1 s.26
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• pp.81-91
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• 1988

The purpose of this study is to investigate the physiolosical responses and subjective wear sensation to the clothes with different cellulose composition. The experimental garments were four types of cellulosic fabrics, respectively composed of $100\%$-cotton, $100\%$-Rayon, cotton/Flax 85/15, and rayon/Flax 85/15 (weft blended), were sewn in blouses with half-length sleeves. Four healthy women were chosen for this experiment. The condition of the experimental room were in two environments: Temp., $25{\pm}1^{\circ}C$, R.H. $60{\pm}3\%$ and Temp., $30{\pm}1^{\circ}C$, R.H. $70{\pm}3\%$, and air velocity was maintained at 0.25 m/sec. The results are as follows. 1) At $25^{\circ}C$, rayon blouse showed the pleasantest feeling because of its excellent humidity sensation and tactile sensation. At $30^{\circ}C$, rayon and flax blended blouse showed most comportable sensation. In both environments, blouse of $100\%$ cotton showed the least pleasant because of high vapor pressure inside the blouse and bad tactile sensation. 2) Vapor pressure inside the blouse and tactile sensation play the most impotant role in comfort. Consequantly the blouse made of $100\%$-cotton which bring low air permeability, moisture regain and water vapor permearbility showed more unpleastness than rayon blouse because it raises temperature, relative humidity and vapor pressure inside the blouse under the hot circumstances In the conditions with much sweat, rayon and flax blended blouse with high stiffness increases comfort better than $100\%$ rayon because the former prevents sticking to the skin.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.9
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• pp.781-788
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• 2013

Grunt(stick-slip) noise happens between rear lining and drum on braking condition while vehicle is returning to steady position after nose-dive. The study presents a new testing and analysis methods for improving brake grunt noise on vehicle. Grunt noise is called a kind of stick slip noise with below 1 kHz frequency that is caused by the surfaces alternating between sticking to each other and sliding over each other with a corresponding change in friction force. This noise is typically come from that the static friction coefficient of surfaces is much higher than the kinetic friction coefficient. For the identification of the excitation mechanism and improvement of grunt noise, it is necessary to study variable parameters of rear drum brake systems on vehicle and to implement CAE analysis with stick slip model of drum brake. The aim of this study has been to find solution parameters throughout test result on vehicle and dynamo test. As a result of this study, it is generated from stick slip between rear lining and rear drum and it can be solved to reduce contact angle of lining with asymmetric and is effected not only brake drum strength but also rear brake size and brake factor.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.267-267
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• 2012

최근 국내 반도체 장비 업체들에 의해서 차세대 반도체용 450 mm 웨이퍼 공정용 장비 개발이 진행 중에 있다. 반도체 산업은 계속해서 반도체 칩의 크기를 작게 하고, 웨이퍼 크기를 늘리면서 웨이퍼 당 칩수를 증가시켜 생산성을 향상해오고 있다. 현재 300 mm 웨이퍼에서 450 mm 웨이퍼를 도입하게 되면, 생산성 뿐만 아니라 30%의 비용절감과 50%의 cycle-time 단축이 기대되고 있다. 장비에 대한 이해와 공정에 대한 해석 능력을 위해 비용과 시간이 많이 들기 때문에 최근 컴퓨터를 활용한 수치 모델링이 진행되고 있다. 또한, 수치 모델링은 실험 결과와의 비교가 필수적이다. 본 연구에서는 450 mm 웨이퍼 공정용 장비의 전자밀도를 cut off probe를 통해 100 mTorr에 서 Ar 플라즈마를 파워에 따라 측정했다. 13.56 MHz 200 W, 500 W, 1,000 W로 입력 파워가 증가하면서 웨이퍼 중심에서 $6.0{\times}10^9#/cm^3$, $1.35{\times}10^{10}#/cm^3$, $2.4{\times}10^{10}#/cm^3$로 증가했다. 450 mm 웨이퍼 영역에서 전자 밀도의 불균일도는 각각 10.31%, 3.24%, 4.81% 였다. 또한, 이 450 mm 웨이퍼용 CCP 장비를 축대칭 2차원으로 형상화하고, 전극에 13.56 MHz를 직렬로 연결된 blocking capacitor ($1{\times}10^{-6}$ F/$m^2$)를 통해 인가할 수 있도록 상용 유체 모델 소프트웨어(CFD-ACE+, EXI corp)를 이용하여 계산하였다. 주요 전자-중성 충돌 반응으로 momentum transfer, ionization, excitation, two-step ionization을 고려했고, $Ar^+$와 $Ar^*$의 표면 재결합 반응은 sticking coefficient를 1로 가정했다. CFD-ACE+의 CCP 모델을 통해 Poisson 방정식을 풀어서 sheath와 wave effect를 고려하였다. Stochastic heating을 고려하지 않았을 때, 플라즈마 흡수 파워가 80 W, 160 W, 240 W에서 실험 투입 전력 200 W, 500 W, 1,000 W일 때와 유사한 반경 방향의 플라즈마 밀도 분포를 보였다. 200 W, 500 W, 1,000 W일 때의 전자밀도 분포는 수치 모델링과 전 범위에서 각각 10%, 3%, 2%의 오차를 보였다. 450 mm의 전극에 13.56 MHz의 전력을 인가할 때, 파워가 증가할수록 전자밀도의 최대값의 위치가 웨이퍼 edge에서 중심으로 이동하고 있음을 실험과 모델링을 통해 확인할 수 있었다.

• Industry Promotion Research
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• v.5 no.4
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• pp.15-28
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• 2020

In this study, the methodology for measuring the structure of the Korean defense market and the competition status, and the characteristics of the Korean defense industry and the market are examined. To analyze the structure of the Korean defense market and the competition status, the market share, concentration ratio, and the Herfindal-Hirschman index are employed based on the annual sales of major Korean defense companies. On a basis of the result of the analysis, the suggestions for the Korean defense market to escape from the monopolistic market to be a competitive geographical market are presented. To present the suggestions, markets that have a similarity with the dense market are analyzed. The government's support policy, the selection of the companies led by the government, and the cost of the military are suggested for the defense market on a basis of analyzing similar markets. With the suggestions, when the government pursues the policies, the defense market sticking to principles and fairness is created and the efficiency of the companies operation is achieved, by enhancing the structure of the market fundamentally and the development of the policies in the industry's perspective.

• Journal of architectural history
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• v.12 no.3
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• pp.149-162
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• 2003

Schulz accepted the existentialist view based on Heidegger's thought and at the same time the objectivist view making fixed this living world, evoking controversies for discussion. He could not see various presentations of the meaning of place because he perceived elements of this world individually. Thus Schulz's mixed system of understanding is sternly different from Heidegger's thought. First, Heidegger suggests that place as existential space represents the occasion revelation of incidents in Dasein. While Schulz recognizes that place is a systematic space predetermined for Dasein. Second, Heidegger interprets the placeness as creative openness in which elements comprising this world face and interact with each other into one. In contrast, Schulz defines each of the elements through signification and regards it as invariable and static. Third, Heidegger perceives that the placeness is expressed with sustainable, complex images through "rift-design" which seeks dynamic interactions between the ground and the world. While Schulz attempts to take "Genius Loci" or "habituated scene" through "gathering" as a concept he regards static and then visualize such structural two factors, producing certain internal images of place. However, limits of Schulz's theory prevent us from exerting complete imagination and discovering the inner creative world of the object. Thus the ultimate goal of paying attention to the placeness, that is, the recovery of individual identity, fails due to the prevalence and abstraction of objectified thinking. In contrast, Heidegger's thought about "openness" is a useful means of realizing the placeness. Openness may be referred to a dynamic coordination in which the earth and the world sustain each other under incessant mutual tensions, but not sticking o each other. "Rift-design" is an openness strategy to cause tense relations by preventing structuralization intentively. This is a creative design that allows seeing original seams of the object.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.6
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• pp.258-263
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• 2008

The fine aggregates of below 2 mm size was fabricated using by the vertical furnace in which the aggregates could be sintered at floating state and its physical properties were analyzed. The liquid formed at the surface of specimens sintered at $1200{\sim}l300^{\circ}C$ induced a gas in core to expand so the denser shell and porous core could be produced. The C series specimen fabricated by crushing an extruded body had an irregular shape and sharp edges but those became spheroidized by bloating due to gas expansion inside. The fine aggregates fabricated in this study was as light as floating in the water and had an apparent density of $0.68{\sim}1.08$. The absorption rate was proportioned to a porosity showing that the pores in core was not closed completely. The properties of fine aggregates fabricated in vertical furnace were similar with those of in an electric muffle furnace but the sticking-together phenomenon by surface fusion was not occurred in the vertical furnace. The aggregates fabricated in this study had a little lower impact resistance than that of natural aggregate but satisfied the unit volume weight standard specified in KS.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.3
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• pp.47-55
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• 2016

The proliferation of the Internet and related technologies has led to a new form of distribution channels, namely online retailers. The conventional offline and the new online retailers have different transaction costs perceived by the consumers in the following perspectives: the accessibility to the product information, the traffic cost and the opportunity cost for the time to visit the store, the delivery time and the possibility of 'touch and feel' to test the quality of the product. In particular, the online retailers have lower distribution cost structure in that they do not have physical stores, which results in lower selling price. Thus they continuously offer price competition against offline retailers using the lower selling cost as competitive weapon. Moreover the emergence of the social commerce is likely to intensify the competition between the online and offline retailers. To survive in this fierce competition, the offline retailers are trying to defend their business interests by sticking to offline transaction in anticipation of increased customer loyalty, customer's preference for 'touch and feel' style shopping, and others. Despite of these efforts, customers who touch and feel a product in an offline store but purchase the product through an online retailer are increasing. To protect such customers, recently, some of the offline retailers began to provide the mobile discount service (MDS) which enables the offline customers to purchase a product at a discounted price through the mobile applications. In business competitions, the price discount strategy is usually considered to secure more market share at the cost of lower profit. In this study, however, we analyze the effect of MDS as a weapon for securing more profit. To do this, we set up a game model between the online and offline retailers which incorporates the effect of the MDS. By numerically analyzing the Nash equilibrium of the game, some managerial implications for using the MDS for more profit are discussed.