Mesoscale modeling of the temperature-dependent viscoelastic behavior of a Bitumen-Bound Gravels

Sow, Libasse,Bernard, Fabrice,Kamali-Bernard, Siham,Kebe, Cheikh Mouhamed Fadel Techno-Press 2018 Coupled systems mechanics Vol.7 No.5

A hierarchical multi-scale modeling strategy devoted to the study of a Bitumen-Bound Gravel (BBG) is presented in this paper. More precisely, the paper investigates the temperature-dependent linear viscoelastic of the material when submitted to low deformations levels and moderate number of cycles. In such a hierarchical approach, 3D digital Representative Elementary Volumes are built and the outcomes at a scale (here, the sub-mesoscale) are used as input data at the next higher scale (here, the mesoscale). The viscoelastic behavior of the bituminous phases at each scale is taken into account by means of a generalized Maxwell model: the bulk part of the behavior is separated from the deviatoric one and bulk and shear moduli are expanded into Prony series. Furthermore, the viscoelastic phases are considered to be thermorheologically simple: time and temperature are not independent. This behavior is reproduced by the Williams-Landel-Ferry law. By means of the FE simulations of stress relaxation tests, the parameters of the various features of this temperature-dependent viscoelastic behavior are identified.

Detonation onset in a thermally stratified constant volume reactor

Sow, Aliou,Lee, Bok Jik,Herná,ndez Pé,rez, Francisco E.,Im, Hong G. Elsevier 2019 Proceedings of the Combustion Institute Vol.37 No.3

<P><B>Abstract</B></P> <P>Understanding detonation development from a flame kernel initiated by a pre-ignition event is important for modern internal combustion (IC) engines operating at boosted conditions. To provide fundamental insights into the effects of bulk gas temperature stratification on the characteristics of detonation development, one-dimensional high fidelity simulations were conducted for a constant volume reactor filled with a thermally stratified reactive stoichiometric hydrogen/air mixture. A linear temperature variation in the upstream end-gas was introduced to represent the thermal stratification of the bulk mixture, and the evolution from the initial deflagration flame front to detonation development was examined. The results showed that the bulk-gas temperature gradient has a significant effect on the run-up time and intensity of the developing detonation. Detailed analyses further revealed that the mechanism of detonation development is qualitatively different for the positive and negative temperature gradient cases. In the former, the detonation development is initiated by the end-gas autoignition at the wall, while the latter exhibits detonation development following the process of the self-acceleration of the flame similar to the deflagration-to-detonation transition. This behavior is attributed to the longer residence time in the end-gas allowing the reinforcement by the interaction of incident and reflected pressure waves during the flame propagation, and results in the peak pressure even higher than the case with the same level of positive temperature gradient. Furthermore, yet another detonation development pattern was observed for the negative temperature gradient condition in the presence of a uniform temperature region just ahead of the flame. In this case, autoignition was found to start in the middle of the bulk end-gas, and subsequently leads to the transition to detonation. The results demonstrate the importance of the bulk gas conditions in predicting the detonation development, which corroborate the existing theoretical framework.</P>

THE INTERRELATIONSHIPS BETWEEN CASINO BRAND IMAGE, CASINO SERVICE, CUSTOMER SATISFACTION AND LOYALTY

Sow Hup Joanne Chan,Yim King Penny Wan,Miyoung Jeon 글로벌지식마케팅경영학회 2018 Global Marketing Conference Vol.2018 No.07

The antecedents of customer loyalty have been a subject of interest to marketers and researchers alike. Few studies have investigated the moderating influence of brand image on customer satisfaction and loyalty. A framework was developed and tested to link casino service quality with satisfaction (affective and cognitive satisfaction) and loyalty (revisit intention and willingness to recommend). The influence of brand image as a moderator was also proposed. Quantitative surveys with 240 mainland Chinese tourists, who were the major source of tourists in Macau, were conducted. All the proposed hypotheses were supported. This study contribute knowledge on customers’ satisfaction and loyalty to casinos by explaining the interrelationships between casino brand image, casino service, customer satisfaction and loyalty. The research demonstrates that satisfied customers are more inclined to revisit and recommend the casino. These relations are stronger for customers who scored higher in image than those who scored lower. The study provides promotional marketing strategies for the casino industry and theoretical suggestions for future study.

`스크롤`의 미디어, 웹툰의 스토리텔링 특성 연구

손현화(Sown, Hyun Hwa),전승규(Jeon, Seung Kyu) 한국디자인학회 2015 한국디자인학회 학술발표대회 논문집 Vol.2015 No.10

The webtoon can be considered the medium of ‘scroll’, whose impact has rapidly grown along with the spread of smartphones and tablets. The webtoon is fundamentally different from any other existing storytelling media, as it exclusively involves scrolling down of a web page on a smart device. This study aims to identify storytelling characteristics of the webtoon by comparing it to other more traditional storytelling media, the comic book and film. Currently, the webtoon is the only storytelling medium that allows infinite canvas. It furthermore enables the author to utilise the auditory and tactile sense in addition to the visual sense. The webtoon is still at its infancy, and its full potential has yet been realised.

Dynamics of a globular protein and its hydration water studied by neutron scattering and MD simulations

Chen, Sow-Hsin,Lagi, Marco,Chu, Xiang-qiang,Zhang, Yang,Kim, Chansoo,Faraone, Antonio,Fratini, Emiliano,Baglioni, Piero IOS Press 2010 Spectroscopy Vol.24 No.1

<P>This review article describes our neutron scattering experiments made in the past four years for the understanding of the single-particle (hydrogen atom) dynamics of a protein and its hydration water and the strong coupling between them. We found that the key to this strong coupling is the existence of a fragile-to-strong dynamic crossover (FSC) phenomenon occurring at around TL=225±5 K in the hydration water. On lowering of the temperature toward FSC, the structure of hydration water makes a transition from predominantly the high density form (HDL), a more fluid state, to predominantly the low density form (LDL), a less fluid state, derived from the existence of a liquid–liquid critical point at an elevated pressure. We show experimentally that this sudden switch in the mobility of hydration water on Lysozyme, B-DNA and RNA triggers the dynamic transition, at a temperature TD=220 K, for these biopolymers. In the glassy state, below TD, the biopolymers lose their vital conformational flexibility resulting in a substantial diminishing of their biological functions. We also performed molecular dynamics (MD) simulations on a realistic model of hydrated lysozyme powder, which confirms the existence of the FSC and the hydration level dependence of the FSC temperature. Furthermore, we show a striking feature in the short time relaxation (β-relaxation) of protein dynamics, which is the logarithmic decay spanning 3 decades (from ps to ns). The long time α-relaxation shows instead a diffusive behavior, which supports the liquid-like motions of protein constituents. We then discuss our recent high-resolution X-ray inelastic scattering studies of globular proteins, Lysozyme and Bovine Serum Albumin. We were able to measure the dispersion relations of collective, intra-protein phonon-like excitations in these proteins for the first time. We found that the phonon energies show a marked softening and at the same time their population increases substantially in a certain wave vector range when temperature crosses over the TD. Thus the increase of biological activities above TD has positive correlation with activation of slower and large amplitude collective motions of a protein.</P>

장애를 지닌 어머니를 위한 양육 지원방안 고찰 : 최근 10년간 연구를 중심으로

이소영,이숙향 이화여자대학교 특수교육연구소 2008 특수교육 Vol.7 No.2

본 연구는 자녀를 둔 여성 장애인에 대한 양육지원 방안을 모색하기 위하여 1998년부터 2008년까지 수행된 국내외 문헌을 조사하였다. 여성 장애인의 자녀양육과 관련된 주제를 다루고 있는 연구는 국내에서 10편, 국외에서 12편이 있었다. 국내 문헌 중 6편은 기존 통계자료를 분석하거나 문헌 연구를 하였으며, 4편은 질적연구였다. 이 중 질적연구의 대상은 주로 지체장애와 시각, 청각 등의 감각장애를 가진 여성이었다. 국외논문은 12편 중 질적연구와 문헌연구가 주를 이루었다. 질적연구나 조사 및 실험연구에 참가한 참가자 장애 특성으로는 지적장애가 5편으로 많았고, 지체장애가 2편이었다. 각 연구 결과들에서 여성 장애인의 양육현황 대해 여성 장애인들의 양육에 대한 인식과 양육 어려움과 영향 요소, 부모의 장애가 자녀의 발달에 미치는 영향, 지원방안으로 나누어 묘사하였다. 이 중 지원방안은 국내 문헌과 국외 문헌에서 제시하는 구체적 내용이 다른 경향이 있어, 따로 나누어 그 결과를 제시하였다. 이러한 결과에 근거하여 장애를 지닌 어머니의 자녀양육 지원 방안과 관련하여 논의되었다. The purpose of this study was to analyze the literature regarding supporting for parenting of the women with disabilities which were published from the 1998 to 2008. There were 10 Korean articles and 12 foreign countries' articles met the criteria for this study. The research was conducted by analyzing research method, participants' characteristics, the result of the research, and supporting strategies that researches suggested. The major findings of this study were as follows: 4 Korean articles were qualitative studies and 4 articles were literature review. The participants for the qualitative studies had mainly physical disabilities and sensory disabilities. In the 12 Foreign articles were mainly qualitative studies and articipants mainly had intellectual disability. In the results of the studies, authors described the parenting state of mothers with disability as follows: perception of the mothers with disability about the parenting, parenting problem and impact element, impact of the mother's disability to the children's development. Supporting strategies for parenting were analyzed from both Korean and foreign articles, respectively. Based on the result, discussions of the study and implications were recommended.

청소년의 여가 사회화 과정에 관한 연구 : An Exploratory Path Analysis

정행도,김수아 명지대학교 예체능연구소 1995 藝體能論集 Vol.5 No.-

The question of when, where, and with whom enduring leisure activities are begin is important both to the development of explanatory and to planning programs. However, leisure socialization has seldom been the central focus of either theory or research. In focusing on leisure generally, the emphasis is placed of the processes through which a youth acquires basic knowledge about leisure and recreation, forms fundamental attitudes and values associated with them. learns various leisure skills and motives. Much of this learning in adolescents occurs through imitation, modeling, and identification with the behavior of others. It then follows that the socialization agent play an important role in transmitting behavioral patterns and basic values relating to leisure, that is judgement as to leisure activities are good and with are bad. The study of this study was to examine process of leisure socialization in adolescents. A causal model with varibles related to leisure socialization was specifically established for the objectives of this study . For the purpose several problems to be identified were as follow: 1. The effect of the demographic and socio-economic backgrounds of the leisure participation in adolescent. 2. The effect of the leisure participation in childhood of the leisure participation in adolescent. 3. The effect of the socializing agents on the leisure participation in adolescent. 4. The effect of the perceived leisure competence on the leisure participation in adolescent. 5. The effect of the leisure attitude of the leisure participation in adolescent. In order to solve the problems the following hypotheses were formulated: Hypotheses Ⅰ. The demographic and socio-economic backgrounds would be influence on the leisure participation in adolescent. Hypotheses Ⅱ. The leisure participation in childhood influences of the leisure participation in adolescent. Hypotheses Ⅲ. The socializing agents influence on the leisure participation in adolescent. Hypotheses Ⅳ. The perceived leisure competence influences of the leisure participation in adolescent. Hypothesed Ⅴ. The leisure attitude influences on the leisure patricipation in adolescent. In order to test the hypotheses 2,085 subject(964 middle school students and 1,121 high school students) among school youth by means of multi-stage systematic stratified random sampling were selected. The data used in the paper were collected by means of a self-administrative questionnaire. The statistics employed the study were correlational analysis, multiple regression, and path analysis. The results obtained from hypotheses test were as follow: 1. Gender, income of family, and grade of school have a direct effect of the leisure participation, and grade of school have a direct effect of the leisure participation, and background of social class have a indirect effect of the leisure participation in youth 2. Experience of leisure participation in childhood has a direct effect on the leisure participation in youth. 3. Peer group and school have a direct effect on the leisure participation, and family has a indirect effect of the leisure patricipation in youth. 4. Perceived leisure competence has a indirect effect on the leisure participation in youth. 5. Lesure attitude has a direct effect of the leisure paritcipation in youth.

Dynamics of a Globular Protein and Its Hydration Water Studied by Neutron Scattering and MD Simulations

Chansoo Kim,Xiang-qiang Chu,Marco Lagi,Sow-Hsin Chen,Kwang-Ryeol Lee 한국진공학회 2011 한국진공학회 학술발표회초록집 Vol.40 No.0

Relationships Between Soil Fetility Indicators and Toposequence: in the Soudano Sahelian Area : Case of the Watershed of Koutango in the Southern Peanut Basin of Senegal

Mateugue Diack,Macoumba Loum,Fary Diome,Khady Sow 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Severity Staging of Chronic Obstructive Pulmonary Disease: Differences in Pre- and Post-Bronchodilator Spirometry

Sheng-Hsiang Lin,Ping-Hung Kuo,Sow-Hsong Kuo,Pan-Chyr Yang 연세대학교의과대학 2009 Yonsei medical journal Vol.50 No.5

Purpose: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines for chronic obstructive pulmonary disease (COPD) uses the post-bronchodilator spirometry for diagnosis and severity staging. We evaluated differences in the severity classification of COPD, based on pre- and post-bronchodilator spirometry. Materials and Methods: From 2000 to 2004, 207 COPD patients who underwent spirometry before and after inhalation of 400 μg of fenoterol were analyzed. A responder to the bronchodilator test (BDT) was defined by the American Thoracic Society (ATS) as an increase in forced expiratory volume in one second (FEV1) or forced vital capacity ≥ 12% and ≥ 200 mL, and by the European Respiratory Society (ERS) as an increase in FEV1 ≥ 10% of the predicted value. COPD severity was classified according to the 2008 GOLD guidelines. Results: For the entire study population, the FEV1 increased by 11.8 ± 12.5% of baseline after BDT and 41.1% and 27.1% of subjects were classified as responders using the ATS and ERS criteria, respectively. Based on pre-BDT spirometry, 55, 85, 58, and 9 patients were classified as Stage I-IV COPD, respectively. Sixty-seven (32.4%) patients changed severity staging after BDT, including 20.0%, 28.2%, 44.8%, and 66.7% of pre-BDT patients Stages I through IV, respectively. More ATS or ERS BDT-responders had a change in severity staging than non-responders (52.9% vs. 18.9% and 62.5% vs. 21.2%, both p < 0.001). Conclusion: Our data suggest that the severity staging of COPD using pre-BDT spirometry might lead to significant differences as compared to staging, based on post-BDT spirometry, as recommended by the current GOLD guidelines. Purpose: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines for chronic obstructive pulmonary disease (COPD) uses the post-bronchodilator spirometry for diagnosis and severity staging. We evaluated differences in the severity classification of COPD, based on pre- and post-bronchodilator spirometry. Materials and Methods: From 2000 to 2004, 207 COPD patients who underwent spirometry before and after inhalation of 400 μg of fenoterol were analyzed. A responder to the bronchodilator test (BDT) was defined by the American Thoracic Society (ATS) as an increase in forced expiratory volume in one second (FEV1) or forced vital capacity ≥ 12% and ≥ 200 mL, and by the European Respiratory Society (ERS) as an increase in FEV1 ≥ 10% of the predicted value. COPD severity was classified according to the 2008 GOLD guidelines. Results: For the entire study population, the FEV1 increased by 11.8 ± 12.5% of baseline after BDT and 41.1% and 27.1% of subjects were classified as responders using the ATS and ERS criteria, respectively. Based on pre-BDT spirometry, 55, 85, 58, and 9 patients were classified as Stage I-IV COPD, respectively. Sixty-seven (32.4%) patients changed severity staging after BDT, including 20.0%, 28.2%, 44.8%, and 66.7% of pre-BDT patients Stages I through IV, respectively. More ATS or ERS BDT-responders had a change in severity staging than non-responders (52.9% vs. 18.9% and 62.5% vs. 21.2%, both p < 0.001). Conclusion: Our data suggest that the severity staging of COPD using pre-BDT spirometry might lead to significant differences as compared to staging, based on post-BDT spirometry, as recommended by the current GOLD guidelines.