• 한국의류학회지
• /
• 제45권5호
• /
• pp.741-757
• /
• 2021

In addition to direct sales to consumers, the direct-to-consumers (D2C) strategy, which provides specialized experiences and services, communicates closely with a consumer's perspective. This tendency is related to the recent trend wherein the luxury fashion system is being transformed into a new luxury. Therefore, this study analyzes the development of online D2C platforms and investigates the characteristics of new luxury from the functional, symbolic, and experiential dimension perspectives based on mobile apps, which is becoming increasingly important among online D2C platforms. Based on the study results, the premium of new luxury fashion displayed in Louis Vuitton's mobile D2C platform in terms of product utility and functionality is newly defined as a usable luxury experience. Moreover, from the heritage perspective, based on the cultural sympathy of the brand contents, we determine that an attachment can be formed between new luxury fashion consumers and brands. Additionally, the personalization service and experiential content on the D2C platform can directly afford emotional and bonding induced brand immersion in a playful way.

• 대한기계학회논문집
• /
• 제8권5호
• /
• pp.476-480
• /
• 1984

본 연구에서는 S15C 및 S45C의 이온 질화에 있어서 확산층 및 합성층의 생성 속도를 계산하였고 이를 기초로 질소의 활성화 에너지를 구하였다.

• Advances in aircraft and spacecraft science
• /
• 제7권6호
• /
• pp.475-493
• /
• 2020

This paper is focused on the characterization of the thermomechanical properties of semicrystalline poly-ether-ether-ketone (PEKK) and of carbon fiberreinforced thermoplastic based laminated composites (C/PEKK) below and above the glass transition temperature (T_g). Differential Scanning Calorimetry (DSC), Dynamic Mechanical Analysis (DMA) and tensile tests are carried out on both pure PEKK polymer and [(±45)₂, +45]_s C/PEKK composite samples, showing a significant similarity in behavior. The employment of a simple micromechanical model confirms that the mechanical and physical behavior of the polymer and that of the matrix in the composite are similar.

• 대한치과기공학회지
• /
• 제30권2호
• /
• pp.39-45
• /
• 2008

Titanium and its alloys are widely used as dental implants materials because of their excellent mechanical properties. However, the alumina and zirconia ceramics are preferred to use as the substitute of Ti implants because there is a problems in esthetics and biocompatibility in Ti implant. The the glass infiltrated alumina ceramics are studied to increase the toughness and biocompatibility. The 45S5 and soda-lime glass powder was mixed with ethanol at ratio of 1:1 and brushed on the surface of alumina. Then it was heat treated in the electric furnace at $1400^{\circ}C$ from 30 min. to 5 hours. The glass powder was controlled from 200 to $350{\mu}m$ using ball milling. After heat treatment, the glass infiltrated specimen was tested in universal testing machine to measure the bending strength. The surface microstructure of each specimen was observed with SEM. The biocompatibility of 45S5 and soda-lime glass coated alumina was investigated using PBS at $36.5^{\circ}C$ incubator. The specimen was immersed in PBS for 3, 5, 7, 10 days. After that, the surface morphology was investigated with SEM. As the results of experiment, the 45S5 bioglass infiltrated alumina show the increase of bending strength according to the increasing of heat treatment time from 30 min. to 5 hours at $1400^{\circ}C$ Finally the 1370N bending strength of alumina increased to 1958N at 5 hours heat treatment, which shows 1.4 times higher. In contrast to this, the soda lime glass infiltrated alumina ceramics shows the convex curve according to heat treatment time. Thus it shows maximum bending strength of 1820N at 1 hour heat treatment of $1400^{\circ}C$ It gives 1.3 times higher. However, the bending strength of soda lime glass infiltrated alumina is decreasing with increasing heat treatment time after 1 hour. The precipitation on the surface of 45S5 glass infiltrated alumina was revealed as a sodium phosphate ($Na_{6}P_{6}O_{24}6H_{2}O$) and the amount of precipitation is increasing with increasing of immersion time in PBS. In contrast to this, there is no precipitation are observed on the surface of soda lime glass infiltrated alumina. This implies that 45S5 glass infiltrated alumina brings more biocompatible when it is implanted in human body.

• 천문학회보
• /
• 제43권1호
• /
• pp.45.2-45.2
• /
• 2018

CS molecule is known to be adsorbed onto dust in cold dense cores, causing its significant depletion in the center region of cores. This study is aimed to investigate the depletion of CS molecule with optically thin $C^{34}S$ molecular line observations, including significance of its differentiation depending on the evolutionary status of the dense cores. We mapped five evolved starless cores, L1544, L1552, L1689B, L694-2 and L1197 using two molecular lines, $C^{34}S$ (J=2-1) and $N_2H^+$ (J=1-0) with NRO 45 m telescope. The $H^2$ column density and temperature structures of each targets were obtained by SED fitting for Herschel continuum images and the internal number density profiles by model fitting. All of the integrated intensity maps of $C^{34}S$ show depletion holes and 'semi-ring-like' distribution, indicating that the depletion of CS is clear and general. The radial profiles of CS abundance also show significant decrease towards the core center, while $N_2H^+$ abundance is almost constant or enhanced. We find that the more evolved cores with higher $H^2$ density tend to have a stronger depletion of CS. Our data strongly support claims that CS molecule generally depletes out in the central regions of starless dense cores and such chemical differentiation is closely related to their evolution.

• 한국해양공학회지
• /
• 제18권1호
• /
• pp.53-62
• /
• 2004

The Purpose of this study is to recycle the waste concrete, which is generated in huge quantities, from construction works. in order to achieve this goal, it is important to determine the compressive strength, workability, slump, and ultrasonic velocity of recycled aggregate concrete. Thus, several experiment parameters are considered, such as water-cement ratios, sand percentage, and fine aggregate composition ratios, in order to apply the recycled aggregate concrete to pre-cast artificial fishing reefs. From the results, it has been shown that the proper mix designs for reef concrete are W/C=45%, S/a=50%, SR50:SN50 in recycled sand and natural sand mix combination case, W/C=45%, S/a=50%, SC50:SN50 in crushed sand and natural sand mix combination case, W/C=45%, S/a=50%, SR50:SC50 in recycled sand and crushd sand mix combination case. Also, this study shows that the shape and surface roughness of fine aggregate particles have an effect on the strength, slump, ultrasonic velocity of tested concrete, and the compressive strength ratios of 7days' and 90days' curing ages of recycled aggregate concrete are about 70% and 110% of 28days' curing age.

• 한국세라믹학회지
• /
• 제45권9호
• /
• pp.497-506
• /
• 2008

The long time of twenty years has passed since Diesel Particulate Filter (DPF) was proposed before the practical use. The main factors that DPF has been put to practical use in this time, are the same time proposal of the evaluation method of SiC porous materials linked to he performance on the vehicle, and that the nature of thermal shock required for the soot regeneration (combustion of soot) in the DPF is different from the conventional requirement for the rather rapid thermal shock. For the requirements, these includ demonstrating utmost the characteristic of SiC's high thermal conductivity, and overcoming the difficulty of thermal expansion of SiC-DPF by dividing the filter into segments binding with the cement of lower Young's modulus, and the innovation of technology around the diesel exhaust system such as Common-Rail system. As the results of these, the cumulative shipments of SiC-DPF have reached about 5 million, and it goes at no claim in the market.

• 미생물학회지
• /
• 제47권1호
• /
• pp.74-80
• /
• 2011

Bacillus cereus에 항균활성을 갖는 박테리오신을 생산하는 유산균을 김치로부터 분리하였다. 선별한 균주는 Bergey's manual, 16S rDNA 분석을 통하여 Lactococcus lactis로 동정되었으며, L. lactis ET45로 명명하였다. ET45가 생산하는 박테리오신은 pH 3.0-11.0까지 안정하였고, 열 안정성 테스트결과 $40-121^{\circ}C$까지 안정함을 확인하였다. 박테리오신의 생산을 위한 최적 조건으로 MRS 액체배지에서 초기 pH 7.5, $30^{\circ}C$에서 18시간 배양하였을 때 최대생산을 보였다. 박테리오신의 항균활성이 proteinase K의 처리로 활성이 소실되어, 박테리오신이 단백질성 물질임을 확인하였다. 박테리오신의 분자량은 tricine sodium dodecyl sulfate polyacryamide gel electrophoresis (TSDS-PAGE)를 통하여 약 4.5 kDa임을 확인하였다.

• 한국미생물·생명공학회지
• /
• 제19권4호
• /
• pp.390-397
• /
• 1991

효모를 Ca-alginate에 고정화하여 회분발효에서 glucose로부터 에탄올을 생산하여 다음의 결과를 얻었다. 100g wet weight/l($4.3 \times 10^9$ cell/l)의 효모를 pH 7.0, 2% 농도의 Ca-alginate에 고정화하였다. 10 beads volume이 에탄올 생산에 최적이었고 30일 (720 시간) 동안 bead의 수명이 지속되었다. 회분식 발효에서 온도안정성은 고정화 효모의 경우 30~$40^{\circ}C$였으며 free cell의 경우 30~$37^{\circ}C$였다. pH 안정성은 pH 4.0~9.0였으며, 에탄올생산 최적 당농도는 15%였다. 최적조건에서 에탄올수율은 0.45, 생산된 에탄올 농도는 67.6g/l 그리고 에탄올 생산성은 1.99g/l.h로 각각 나타났다.

• 한국구조물진단유지관리공학회 논문집
• /
• 제10권6호
• /
• pp.105-113
• /
• 2006

본 연구는 잔골재와 굵은 골재를 전량 플라이애쉬로 치환한 콘크리트의 공학적 특성을 밝히기 위한 실험적 연구의 결과이다. 그리고 플라이애쉬 전량 치환 콘크리트의 유동성 저하 문제를 추가수량($W_f$)으로 해결하고자 하였다. 실험은 물-시멘트 비($W_c/C$)를 0.35, 0.45 그리고 물-플라이애쉬 비($W_f/FA$)를 0.35, 0.45로 하였다. 플라이애쉬 치환은 P와 Q의 두 가지 방법으로 하였다. P 방법은 플라이애쉬와 첨가수량($W_f$)의 중량이 골재의 중량과 같은 배합법이다[$FA+W_f$ = G (또는 S)]. Q 방법은 플라이애쉬와 골재의 중량이 같고 첨가수량($W_f$)을 추가하는 배합법이다 [$FA+W_f$ > G (또는 S)]. 실험은 굳기 전 콘크리트의 특성과 3, 7, 28 및 91일 압축강도 특성을 측정하였다. 실험결과 압축강도는 $Wc/C=0.35$, $W_f/C=0.35$ 일 때, P 치환법 중에서 잔골재 치환이 다른 배합들보다 향상되었다. Q 방법은 P 방법에 비해 유동성은 향상되었으나, 압축강도는 그렇지 않았다. 실험결과는 잔골재와 굵은 골재를 플라이애쉬로 전량 치환한 콘크리트의 유동성과 강도 특성이 향상됨을 알 수 있었고, 플라이애쉬 치환방법으로 효과적임을 보여주었다.