충돌분무의 액적 거동에 미치는 비등방성 난류특성의 영향에 대한 수치해석 연구

고권현(G. H. Ko),유홍선(H. S. Ryou) 한국전산유체공학회 2003 한국전산유체공학회지 Vol.8 No.4

It is an aim of this study to perform extensive numerical study for analyzing the anisotropic turbulence effects on spatial and temporal behaviors of droplet for impinging sprays. The turbulence model of Durbin is used for comparisons with the k-E model. The turbulence-induced dispersions of droplets are consider to describe the anisotropy of turbulence effectively and spray/wall interactions are simulated using the model of Lee and Ryou. Present study investigates the overall and the internal structures of impinging diesel sprays such as spray shapes, radius and height of wall sprays, Sauter mean diameter (SMD), local droplet velocity, and local gas velocity and compared the results with experimental data by two adopted turbulence models. When the anisotropy effect of turbulence is included, better predictions for both gas and droplet tangential velocities are obtained, compared to the k-ε model. It is concluded that anisotropic effect of turbulence should be considered for simulating impinging diesel sprays.

Host People's Kindness and Migrant Workers' Cultural Adaptation: Evidence from South Korea

Jihyun Ryou(Jihyun Ryou),Sang-Yeon Kim(Sang-Yeon Kim) 한국학술연구원 2022 Korea Observer Vol.53 No.4

This study purports to determine the predictors of migrant workers' cultural adaptation in South Korea. In the main, we examined the extent to which the level of inter-/intracultural socializing, exposure to local/native media, and host culture receptivity affect the level of cultural adaptation in cognitive, affective, behavioral domains. Potential impacts of demographic factors (e.g., age, sex, ethnicity, marital status, living alone vs. with family, education level, residency in years, perceived cultural similarity) were also explored. To find answers to the research questions, a total of 634 migrant workers from 37 different nations were reached using a snowball sampling. Surveys were collected in 12 districts of Seoul, the capital of South Korea, and 21 adjacent metropolitan areas. Results indicate that intercultural interaction with host people and media exposure to local contents tend to help improve their knowledge about South Korea (e.g., language, culture). With all else equal, migrant workers treated kindly by Koreans at the workplace and in service sectors, and those living with family, compared to those who live alone, tended to enjoy a greater satisfaction with work and life in South Korea and were more willing to stay. Practical implications for Korean policymakers include encouraging competent migrant workers to move together with the family, making administrative efforts to further simplify the documentation process, and initiating public campaigns to raise host culture receptivity among Korean citizens.

Development and Application of a New Spray Impingement Model Considering Film Formation in a Diesel Engine

Ryou, Hong-Sun,Lee, Seong-Hyuk,Ko, Gwon-Hyun,Hong, Ki-Bae The Korean Society of Mechanical Engineers 2001 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.15 No.7

The present article presents an extension to the computational model for spray/wall interaction and liquid film processes that has been dealt with in the earlier studies (Lee and Ryou, 2000a). The extensions incorporate film spread due to impingement forces and dynamic motion induced by film inertia to predict the dynamic characteristics of wall films effectively. The film model includes the impingement pressure of droplets, tangential momentum transfer due to the impinging droplets on the film surface and the gas shear force at the film surface. Validation of the spray/wall interaction model and the film model was carried out for non-evaporative diesel sprays against several sources of experimental data. The computational model for spray/wall interactions was in good agreement with experimental data for both spray radius and height. The film model in the present work was better than the previous static film model, indicating that the dynamic effects of film motion should be considered for wall films. On the overall the present film model was acceptable for predication of the film radius and thickness.

A note on Fuzzy Vietories Topology

Ryou, J.H. Korean Institute of Intelligent Systems 2000 한국지능시스템학회논문지 Vol.10 No.2

We introduce the concept of a fuzzy Vietories topology and we obtain some properties.

Drawing the Line

Ryou Kyongjoo H. 숙명여자대학교 아세아여성문제연구소 1999 Asian Women Vol.8 No.-

Characters S: An artist/illustrator, around 30, shortish, well-mannered M: S's separated wife, near 40 Ss: S's sister, in her late 20s, a writer An unidentified Voice Willard: S's agent (never appears on the scene) Guapa: S's Golden retriever kay: Willard's secretary

A Study on the Strength Property of Mortars with Silicon Carbide as an Additive

Ryou, Jae Suk(류재석),Kim, Hong Gi(김홍기),Kim, Jun Hyeong(김준형),Woo, Byeong Hun(우병훈),Jeon, In Kyu(전인규) 한국콘크리트학회 2018 한국콘크리트학회 학술대회 논문집 Vol.30 No.2

The Importance of Word-for-Word Translation Or How to Minimize What Is Lost in Poetic Translating

Ryou, KyongJoo H. 한국비교문학회 2003 比較文學 Vol.30 No.-

번역된 시 본문이 지닌 과도한 상화화는, 특별히 이 상황화가 외견상의 본문의 매끄러움을 위해서 원래의 의미 그 이상으로 나아갈 경우 위험성이 있다. 문학작품을 번역하는데 늘 따라오는 어려움이 시 번역에서는 더욱 심해지는데 이는 문학작품을 다른 종루의 글과 구별케 하는 속성들이 시에서는 더욱 강하게 드러나기 때문이다. 게다가 시가 지닌 특별한 요소들, 즉 소리, 리듬, 운율 그리고 세쥬라(caesura) 같은 것들은 번역자에게 엄청난 부담을 주게된다. 이런 상황에서, 과도한 수정이나 첨가와 같은 시도를 멈추게 하는 힘은 기본적으로 본문 그 자체이다. 비록 몇몇 학자들은 축어적인 번역을 조소 어린 시선으로 바라보지만, 원본이 지닌 미묘한 암시들과 시사하는 바들을 가능한 한 손상시키지 않으면서도 원래의 의미에 충실한 시 번역본을 만드는 일은 번역이 매끄럽든 아니든 먼저 문자적 번역의 원리들에 기초해야 한다. 시 본문을 갖고 있는 모든 면들, 즉 단어는 단어대로, 운율은 운율대로, 은유는 은유대로 모든 차원들을 면밀하게 검토하고 살핀 후에야 비로소, 번역자는 최소한 원본이 지닌 본질의 얼마를 번역본 가운데 살려낼 수 있기를 소망할 수 있는 것이다. 위에서 본 소고가 주장하는 바는 다음과 같은 두 가지의 사례를 중심으로 개진될 것인데, 그 중 하나는 미국에서 출판될 릴케의 번역물에 대한 수용이요, 다른 하나의 가장 자주 번역되어지고 또한 가장 자주 시선집에 소개되는 김소월의 「진달래 꽃」이다.

Confucianism

Ryou, Soon Ha 장로회신학대학교 세계선교연구원 2000 선교와 신학 Vol.6 No.-

Low temperature NO adsorption over hydrothermally aged Pd/CeO₂ for cold start application

Ryou, YoungSeok,Lee, Jaeha,Lee, Hyokyoung,Kim, Chang Hwan,Kim, Do Heui Elsevier 2018 CATALYSIS TODAY - Vol.307 No.-

<P><B>Abstract</B></P> <P>Pd/CeO<SUB>2</SUB> catalyst hydrothermally aged at 750°C for 25h was employed for NO adsorption at low temperature (80–160°C). For comparison, Pt or Pt-Pd supported on CeO<SUB>2</SUB> or Al<SUB>2</SUB>O<SUB>3</SUB> catalysts were also applied. Analysis of the hydrothermally aged catalysts clearly indicates that PGM (Pt and/or Pd) on CeO<SUB>2</SUB> is more resistant to sintering than that on Al<SUB>2</SUB>O<SUB>3</SUB> support. Reducibility test of Pd/CeO<SUB>2</SUB> by H<SUB>2</SUB>-TPR exhibits H<SUB>2</SUB> spillover from Pd to CeO<SUB>2</SUB> support, attributed to the strong interaction between Pd and CeO<SUB>2</SUB>. NO adsorption/desorption results demonstrate that CeO<SUB>2</SUB>-based catalysts exhibit superior NO adsorption ability than Al<SUB>2</SUB>O<SUB>3</SUB>-based catalysts. In addition, PGM/CeO<SUB>2</SUB> catalysts shows the desirable desorption temperature for cold start application. The influence of reactant in stream, NO adsorption time, and temperature on low temperature NO adsorption over Pd/CeO<SUB>2</SUB> is also examined to advance the understanding of NO adsorption/desorption behavior. DRIFT results of adsorbed NO<SUB>x</SUB> species on Pd/CeO<SUB>2</SUB> during NO adsorption/desorption prove that NO<SUB>x</SUB> desorption peaks at 250, 300, and 450°C originate from weakly bound nitrite, nitro-nitrito species, and nitrate species, respectively. In Pd/CeO<SUB>2</SUB> catalyst, Pd plays a role in providing additional NO adsorption site arising from the intimate interaction between Pd and CeO<SUB>2</SUB> and promoting the oxidation from adsorbed nitrite to nitrate. It can be summarized that Pd/CeO<SUB>2</SUB> can be a good candidate as low temperature NO adsorption catalyst for cold start application.</P> <P><B>Highlights</B></P> <P> <UL> <LI> PGM on CeO<SUB>2</SUB> is more stable than that on Al<SUB>2</SUB>O<SUB>3</SUB> after hydrothermal treatment. </LI> <LI> CeO<SUB>2</SUB>-based catalyst has better NO adsorption ability than Al<SUB>2</SUB>O<SUB>3</SUB>-based catalysts. </LI> <LI> Pd improves NO adsorption ability of CeO<SUB>2</SUB> by promoting oxidation of NO<SUB>x</SUB> on CeO<SUB>2</SUB>. </LI> <LI> Pd on CeO<SUB>2</SUB> activates new NO adsorption sites which desorb NO at around 300°C. </LI> <LI> Pd/CeO<SUB>2</SUB> has highest NO adsorption capacity and desirable desorption temperature. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

The Effects of Water Mist on the Compartment Fire

Ryou, Hong-Sun,Kim, Sung-Chan The Society of Air-Conditioning and Refrigerating 2004 International Journal Of Air-Conditioning and Refr Vol.12 No.1

The present study investigates the fire suppression characteristics using a water mist fire suppression system. Numerical simulations of fire suppression with water mist are performed with considering the interaction of fire plume and water spray. The predicted temperature fields of smoke layer are compared with those of measured data. Numerical results agree with the experimental results within $10^{\circ}C$ in the case without water mist. In the case of fire suppression with water mist, numerical results do not predict well for temperature field in the gradual cooling region after water mist injection. But the predicted results of initial fire suppression are in good agreement with those of measured data. The reason for the discrepancy between predicted and measured data is due to the poor combustion modeling during the injection of water mist. More elaborate models for numerical simulation are required for better predictions of the fire suppression characteristics using water mist.