• Title/Summary/Keyword: retro

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Theoretical Studies on the Gas-Phase Pyrolysis of Esters The effect of ${\alpha}$- and ${\beta}$-methylation of Ethyl Formates

  • Ikchoon Lee;Ok Ja Cha;Bon-Su Lee
    • Bulletin of the Korean Chemical Society
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    • v.11 no.1
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    • pp.49-54
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    • 1990
  • The gas-phase thermolysis reactions of ${\alpha}$- and ${\beta}$-methylated ethyl formates, Y = $CH-X-CHR_1CH_2R_2$ where X = Y = O or S and $R_1\;=\;R_2$ = H or $CH_3$, are investigated theoretically using the AM1 method. The experimental reactivity order is reproduced correctly by AM1 in all cases. The thermolysis proceeds through a six-membered cyclic transition state conforming to a retro-ene reaction, which can be conveniently interpreted using the frontier orbital theory of three-species interactions. The methyl group substituted at $C_{\alpha}\;or\;C_{\beta}$ is shown to elevate the ${\pi}$-HOMO of the donor fragment (Y = C) and depress the ${\sigma}^{\ast}$-LUMO of the acceptor fragment ($C_{\beta}$-H), increasing the nucleophilicity of Y toward ${\beta}$-hydrogen which in turn increases the reactivity. The two bond breaking processes of the $C_{\alpha}$-X and $C_{\beta}$-H bonds are concerted but not synchronous so that the reaction takes place in two stages as Taylor suggested. The initial cleavage of $C_{\alpha}$-X is of little importance but the subsequent scission of $C_{\beta}$-H occurs in a rate determining stage.

Supersonic and Subsonic Projectile Overtaking Problems in Muzzle Gun Applications

  • Gopalapillai, Rajesh;Nagdewe, Suryakant;Kim, Heuy-Dong;Setoguchi, Toshiaki
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.03a
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    • pp.711-722
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    • 2008
  • A projectile when passes through a moving shock wave, experiences drastic changes in the aerodynamic forces as it moves from a high-pressure region to a low pressure region. These sudden changes in the forces are attributed to the wave structures produced by the projectile-flow field interaction, and are responsible for destabilizing the trajectory of the projectile. These flow fields are usually encountered in the vicinity of the launch tube exit of a ballistic range facility, thrusters, retro-rocket firings, silo injections, missile firing ballistics, etc. In earlier works, projectile was assumed in a steady flow field when the computations start and the blast wave maintains a constant strength. However, in real situations, the projectile produces transient effects in the flow field which have a deterministic effect on the overtaking process. In the present work, the overtaking problem encountered in the near-field of muzzle guns is investigated for several projectile Mach numbers. Computations have been carried out using a chimera mesh scheme. The results show that, the unsteady wave structures are completely different from that of the steady flow field where the blast wave maintains a constant strength, and the supersonic and subsonic overtaking conditions cannot be distinguished by identifying the projectile bow shock wave only.

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What Kind of Fun Food Marketing Do Customers Want?

  • CHA, Seong-Soo;LEE, Min-Ho
    • The Korean Journal of Food & Health Convergence
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    • v.7 no.3
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    • pp.1-11
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    • 2021
  • Purpose of the research: This study aims to explain the state of marketing using fun among recent popular marketing strategies. Although companies are using various differentiated marketing strategies to gain a competitive edge, among them, fun marketing has constituted the most effective area of interest recently. Research design and methodology: To extract the customer selection attributes of fun marketing, after reviewing the literature, six optional attributes were selected from the factors of fun marketing towards consumers such as funny design, language play, celebrity use, funny taste, how to eat, and newtro (new + retro). Out of 300 questionnaires, 276 were used for analysis, excluding unscrupulous or incomplete questionnaires. The results were reviewed for validity and reliability using SPSS andAMOS, and the hypothesis was verified using structural equation modelling (SEM). Principal results: The results showed that funny design, language play, and newtro statistically significantly affected customer satisfaction, but celebrity use, funny taste, and eating methods had no significant effect. It was also confirmed that satisfaction had a statistically significant effect on repurchase intention. Major conclusions: This study can serve as basic data to enhance the marketing strategy of the food service industry, and it provides theoretical and practical implications.

Aerodynamics of a wing section along an entry path in Mars atmosphere

  • Zuppardi, Gennaro;Mongelluzzo, Giuseppe
    • Advances in aircraft and spacecraft science
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    • v.8 no.1
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    • pp.53-67
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    • 2021
  • The increasing interest in the exploration of Mars stimulated the authors to study aerodynamic problems linked to space vehicles. The aim of this paper is to evaluate the aerodynamic effects of a flapped wing in collaborating with parachutes and retro-rockets to reduce velocity and with thrusters to control the spacecraft attitude. 3-D computations on a preliminary configuration of a blunt-cylinder, provided with flapped fins, quantified the beneficial influence of the fins. The present paper is focused on Aerodynamics of a wing section (NACA-0010) provided with a trailing edge flap. The influence of the flap deflection was evaluated by the increments of aerodynamic force and leading edge pitching moment coefficients with respect to the coefficients in clean configuration. The study was carried out by means of two Direct Simulation Monte Carlo (DSMC) codes (DS2V/3V solving 2-D/3-D flow fields, respectively). A DSMC code is indispensable to simulate complex flow fields on a wing generated by Shock Wave-Shock Wave Interaction (SWSWI) due to the flap deflection. The flap angle has to be a compromise between the aerodynamic effectiveness and the increases of aerodynamic load and heat flux on the wing section lower surface.

A Study on the Design Characteristics of Athleisure Look in Image-based SNS (이미지 기반 SNS에 나타난 애슬레저 룩의 디자인 특성 연구)

  • Kwon, Suehee;Park, Minjung
    • Journal of the Korean Society of Clothing and Textiles
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    • v.45 no.1
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    • pp.17-27
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    • 2021
  • The pursuit of a healthier life has created life style changes through exercise; in addition, an athleisure look as well as a combination of everyday clothes and sportswear has rapidly spread through sharing based on image-based SNS. Fashion related images shown in an image-based SNS are considered important resources for grasping micro-needs with regard to the sensibility of consumers. Therefore, this study analyzes the design characteristics of an athleisure look shown in image-based SNS. In order to analyze the athleisure look, images of the entire garment were collected and classified to enable content analysis methods that analyzed the design characteristics of each type. As a result, types were classified as sporty-athleisure, modern-athleisure, high-end athleisure, retro-athleisure, and romantic-athleisure. Looking at the characteristics of the athleisure look, it was shown that the design characteristics of each type were well expressed through differences in the direction, material, and details by matching between the items used. This study can be used in design development processes by deriving the characteristics of athleisure looks through an analysis of fashion images that appear in image-based SNS.

A New Component Software for Hierarchical Visualization for Whole Genomes (전 유전체 단계적 가시화를 위한 새로운 컴포넌트 소프트웨어)

  • Chung, Woo-Keun;Cho, Chi-Young;Cho, Hwan-Gue
    • Proceedings of the Korea Information Processing Society Conference
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    • 2009.04a
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    • pp.988-991
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    • 2009
  • 게놈 데이터의 지속적인 증가로 인해 생물정보학에서 유전체 정보를 체계적으로 저장하고 열람하는 효과적이고 효율적인 시스템을 확립하는 것은 중요한 일이다. 잘 알려진 게놈 정보의 계층적 구조처럼 우리는 게놈의 내부 구조를 연구하기 위한 우수한 툴도 필요하다. 게놈 연구에 있어서 한 가지 문제는 유전체 정보는 너무 거대해서 표준적인 정보 처리를 이용하는 간단한 툴로는 작업하기 어려운 점이다. 예를 들어 특정 게놈 데이터 크기는 100메가 바이트를 넘는다. 추가적으로 유전자, promoters, retro-elements(HERV), operons, exon-introns와 같은 많은 게놈 요소들이 있다. 전통적으로 생물학자 들은 게놈 연구를 위해 툴을 아무거나 사용하지 않고, 보통 그들의 연구에 좋은 툴을 채택하려 노력했다. 게놈 연구에서 기본적이고 주시할만한 단계는 다른 종과 유전체 요소를 비교하기 위해 위치를 인식할 수 있도록 하나의 화면에 모든 게놈 데이터를 시각화하는 것이다. 생물학자에게 툴의 개발은 많은 시간이 걸리고 시행착오를 겪기 쉬운 일이다. 이 논문에서 우리는 전체 게놈 중 어떤 게놈 요소를 시각화하는 컴포넌트 웨어의 셋을 제안한다. 그리하여 실험을 목적으로 생물학자를 만나서 우리의 셋을 이용하여 컴포넌트를 조합하여 소프트웨어를 만드는 것은 비교적 간단한 작업이다. 이 실험에서 우리는 HERV와 연동되는 게놈 요소를 보여주는 툴을 어떻게 우리의 컴포넌트 웨어를 간단히 조합하여 구축하는지를 보여주겠다.

A Study on Food Repurchase Intention Using Nostalgia Marketing

  • Bo-Kyung Seo;Seong Soo CHA
    • The Korean Journal of Food & Health Convergence
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    • v.9 no.3
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    • pp.11-17
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    • 2023
  • This study aims to investigate the effect of the selection attribute of Newtro (New + Retro) product marketing, which is a recent topic in the food industry, on consumer satisfaction. Newtro marketing, also known as Newtro-style marketing, is a marketing strategy that emerged in South Korea, particularly in the food industry. Newtro marketing aims to appeal to consumers' nostalgia for the past while incorporating contemporary elements. As a research method, a survey was conducted on the importance of selection attributes and repurchase intention of Newtro food for consumer groups of various age groups ranging from teenagers to those in their 40s or older. To analyze the demographic content of the sample, frequency analysis of the SPSS statistical package was performed, and structural equation modeling was performed using the AMOS program for confirmatory factor analysis and discriminant validity analysis. The analysis results are as follows. First, Package Design, Perceived Healthiness, and Emotional Taste, optional attributes of Newtro marketing, significantly affected satisfaction. Second, satisfaction was found to have a statistically significant effect on repurchase intention. However, Functional Flavor did not statistically affect satisfaction. This study empirically analyzed the importance of consumers' selection attributes for the recently popular food Newtro marketing and suggested implications.

A Study on the Production of 2D Pixel Game Objects Using Basic Shape (기본도형을 활용한 2D Pixel 게임 오브젝트 제작연구)

  • KIM, Do-Kyung
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2022.07a
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    • pp.213-215
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    • 2022
  • 현재 게임들에서 Retro 풍이 일면서 다시 2D그래픽이 주목을 받고 있는 현상이 발생하고 있다. 물론 과거에도 2D 그래픽풍의 게임이 없었던 것은 아니나 근래에 들어서는 그 양상이 좀 더 진화되어 유저들에게 어필을 하고 있어 주목이 되고 있다. 현재 출시된 멀티 플랫폼 게임 엔진 중 게임 개발사에서 많이 사용 중인 엔진은 Unity3D 엔진이다. 본 논문에서는 Unity3D 엔진을 이용한 2D게임 그래픽 제작에 대해 논하고자 한다. 유니티 엔진은 C#, 자바스크립트로 코드를 작성할 수 있다는 이유로 C#과 모노 기반 코드로 개발되었다고 알려져 있었다. 실제로 엔진의 런 타임 부분은 C++과 마이크로소프트 닷넷 API, 에디터 프로그램은 C#으로 개발되었다. 스크립트는 유니티 내에서 바로 수정은 하지 못하고 Mono Develop등 유니티를 지원하는 스크립트 에디터에서 수정할 수 있다. 이에 본 논문에서는 멀티 플랫폼 게임 엔진을 이용한 2D 게임 그래픽인 Pixel Art 구현을 제안 하고자한다. 이를 통해서 다양한 멀티 플랫폼 기반의 게임 설계 및 개발에 도움이 되었으면 한다. 어떤 요소들이 2D게임을 선택하는 데에 있어 영향을 끼치는가에 대해서 알아보고, 세부항목에 따른 기본 도형을 이용한 게임 오브젝트 제작의 특징과 그 이유가 사용자에게는 어떤 의미를 가지는가에 대한 것을 알 수 있다.

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A Study on The Grunge Fashion of the 1990's and 2000's (1990년대와 2000년대의 그런지(Grung) 패션에 관한 연구)

  • Chung Yu Kyoung;Geum Key-Sook
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.3_4 s.141
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    • pp.449-461
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    • 2005
  • The purpose of this study is to rediscover the hidden value of non-mainstreamers style which has been overlooked for the past decade by investigate the aesthetics and formative features of the Grunge fashion. The Grunge fashion was derived from explosive popularity of the early 90's grunge music. Grunge was the alternative anti-thesis against mainstream pop music and anti-fashion against mainstream fashion. Dirty, rubbish grunge style of the poor street youth and grunge musicians have raised to the high fashion by designers. And These trial of designers made people to notice the value of the non-mainstreamers street style like grunge. Actually, the grunge brought the shock with many argument to the 90's fashion field. But now, It became the classic of the street fashion. And It has potent influence on the music, culture and high fashion. The Grunge is a kind of links between music and fashion, street fashion and high fashion, sub culture and mainstream culture, the past and now. Grunge isn't only a fashion of appearance. It is the attitude of wearing clothes and living a life. Variety grunge style in the international street fashion, high fashion, typical musicians's fashion of the 1990's and the 2000's was researched for this study. These materials were gathered from music magazines, fashion magazines, movies, musics and books. As a results of analysis, Grunge has the formative features like mix & match, layering, patchwork, primitive edge, rag, retro, recycle, kinderwhore, sneer scribbling, disheveled hair. Grunge also has the Aesthetic features like the beauty of $disorder{\cdot}\;disharmony{\cdot}\;incompleteness{\cdot}\;kitsch{\cdot}\;poverty{\cdot}\;alternative{\cdot}\;eclectic{\cdot}$symbiosis. For the last 10 years, These features changed our fashion be more pluralistic and dynamic.

Aesthetic Characteristics of Western Women's Costumes on Artistic Paradigm Shifts and Modern Expression in Fashion (예술적 패러다임 전환기에 나타난 서양 여성 복식의 미적 특성과 현대적 표현)

  • Jun, Yuh Sun;Kim, Young Sam
    • Fashion & Textile Research Journal
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    • v.16 no.6
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    • pp.835-848
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    • 2014
  • This study investigated the relationship between inner characteristics manifested through the characteristics of artistic styles and formativeness manifested through external expressions of architectural styles in the early Medieval Period and early Renaissance Period. The method applied to this study is as follows. First, a historical document research was conducted centering on academic theses, related books, and academic databases; in addition, a case study identified the aesthetic characteristics of women's clothes. The conclusion of this study is as follows. First, the following is the analysis of the relationship between the artistic mode and architectural formativeness in the early Medieval Period and early Renaissance Period that represent a turning point in artistic paradigms. Second, the inner characteristics and eclecticism of the artistic mode literally appear in the formativeness of architectural style in the early Medieval Period, and the eclecticism in the architectural style appears to be expressed through a combination with new styles based on the application of the retro mode such as the eclectic adoption of cultural styles of various regions based on the tradition and technology of ancient Rome. Third, the trend of the aesthetic characteristics commonly appear in the modern style of expression related to the aesthetic characteristics of western women's clothes in the early Medieval Period; in addition, the early Renaissance Period was analyzed as decorativeness and respectively manipulability.