편백나무의 반응 조건별 저속 열분해 생성물 특성 분석 연구

유승한,박진제,김민수,류창국,박정극 한국열환경공학회 2019 한국열환경공학회 학술대회지 Vol.2019 No.-

Recurrent-neural-network-based identification of a cascade hydraulic actuator for closed-loop automotive power transmission control

유승한,Jin-Oh Hahn 대한기계학회 2012 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.26 No.5

"By virtue of its ease of operation compared with its conventional manual counterpart, automatic transmissions are commonly used as automotive power transmission control system in today’s passenger cars. In accordance with this trend, research efforts on closed-loop automatic transmission controls have been extensively carried out to improve ride quality and fuel economy. State-of-the-art power transmission control algorithms may have limitations in performance because they rely on the steady-state characteristics of the hydraulic actuator rather than fully exploit its dynamic characteristics. Since the ultimate viability of closed-loop power transmission control is dominated by precise pressure control at the level of hydraulic actuator, closed-loop control can potentially attain superior efficacy in case the hydraulic actuator can be easily incorporated into model-based observer/controller design. In this paper, we propose to use a recurrent neural network (RNN) to establish a nonlinear empirical model of a cascade hydraulic actuator in a passenger car automatic transmission, which has potential to be easily incorporated in designing observers and controllers. Experimental analysis is performed to grasp key system characteristics, based on which a nonlinear system identification procedure is carried out. Extensive experimental validation of the established model suggests that it has superb one-step-ahead prediction capability over appropriate frequency range, making it an attractive approach for model-based observer/controller design applications in automotive systems."

수학과 기하영역 학습을 위한 온라인 RPG 교수 게임의 설계

유승한,이재인 한국정보교육학회 2001 정보교육학회논문지 Vol.5 No.3

초 저 에너지 이온주입으로 고 조사량 B 이온 주입된 실리콘의 Deactivation 현상

유승한,노재상,Yoo, Seung-Han,Ro, Jae-Sang 한국재료학회 2003 한국재료학회지 Vol.13 No.6

Shallow $p^{+}$ n junction was formed using a ULE(ultra low energy) implanter. Deactivation phenomena were investigated for the shallow source/drain junction based on measurements of post-annealing time and temperature following the rapid thermal annealing(RTA) treatments. We found that deactivation kinetics has two regimes such that the amount of deactivation increases exponentially with annealing temperature up to $850^{\circ}C$ and that it decreases linearly with the annealing temperature beyond that temperature. We believe that the first regime is kinetically limited while the second one is thermodynamically limited. We also observed "transient enhanced deactivation", an anomalous increase in sheet resistance during the early stage of annealing at temperatures higher than X$/^{\circ}C$. Activation energy for transient enhanced deactivation was measured to be 1.75-1.87 eV range, while that for normal deactivation was found to be between 3.49-3.69 eV.

A Stag Hunt Game with Social Norms

유승한 한국계량경제학회 2013 계량경제학보 Vol.24 No.3

This paper studies a stag hunt game in which each player’s payoff depends on the level of social norms in a community. First, we establish conditions under which without social norms, there exists a unique equilibrium regarding the cooperation level, but with social norms, there can be multiple equilibria. Second, we provide the comparative statics analysis such that for a statics framework,the local stability of an interior equilibrium works as a sufficient condition under which the cooperation level increases as the degree of social norms increases;and for a dynamic framework, the cooperation level always increases with social norms.

수 종의 생약제제가 함유된 치약이 치주질환에 미치는 영향

유승한,홍성우,김탁,박영채,김흥식,유용욱,유형근,신형식,You, Seung-Han,Hong, Sung-Woo,Kim, Tak,Park, Young-Chae,Kim, Heung-Shik,Yu, Yong-Uk,Yu, Hyeong-Geun,Shin, Hyung-Shik 대한치주과학회 1999 Journal of Periodontal & Implant Science Vol.29 No.4

Recently many researches on plaque removal effect and therapeutic effect of toothpaste containing natural medicines are being studied in early periodontal diseases. The purpose of this study is to examine the clinical and microbiological effect of toothpaste containing natural medicines such as camomile, rhatany, myrrh,sage oil, glycyrrhetinic acid and vitamin E. Sixty three subjects with gingivitis were divided into an experimental group which performed normal oral hygiene procedure with toothpaste containing natural medicines and vitamine E and a control group which also performed normal oral hygiene procedure with Syrinmed? toothpaste without containing herbal extracts and vitamine E. At the baseline, 2 weeks, and 4 weeks, subjects were analyzed for clinical study and microbiological study. After 2 weeks and 4 weeks use of their respective toothpastes, statistically significant decreases of gingival index, plaque index, and bleeding index were shown in both the control and the experimental group. The degree of decrease was more significant in the experimental group than the control group. A statistically significant decrease of pocket depth, and gingival crevicular fluid were shown in both the control and lie experimental group. A statistically significant increase of cocci was shown in both the control and the experimental group, the degree of increase was more significant in the experimental group than control group. A statistically significant decrease ofnon-motile rods, and motile rods were shown in both the control and the experimental group, the degree of decrease was more significant in the experimental group than the control group. Spirochetes increased weakly in both the control and the experimental group but a statistic significance was not shown. A statistically significant decrease of anaerobic bacteria, aerobic bacteria, and black pigmented Bacteroides were shown in both the control and the experimental group. These results indicate that the use of toothpaste containing natural medicines is effective in the prevention and the treatment of periodontal diseases.

학급 블로그 활동이 초등학교 학생들의 자아 존중감에 미치는 영향

유승한,성영훈,이재인 한국정보교육학회 2005 정보교육학회논문지 Vol.9 No.2

블로그는 트랙백이라는 기술을 이용하여 개인이 생산한 정보나 일상의 기록을 웹 상에서 다수의 사람들과 공유할 수 있게 하는 미디어 체계이다. 즉 기존까지 행하여 진 웹활동이 수동적이었고 일방적이었던 반면 블로그는 개인이 주체적이고 사회의 일원으로써 관심을 받을 수 있게되는 계기가 되었다. 이에 본 연구에서는 블로그 활 동이 학생들의 일반적, 사회적 자아 존중감에 어떠한 영향을 주는 가를 알아보기위해 학급 블로그 시스템을 설계하여 실제 운영해 보았다. 그 결과 6개월간 블로그를 활용 한 집단이 그렇지 않은 집단에 비해 일반적 자아 존중감, 사회적 자아존중감 등 대부 분의 자아 존중감 수치가 유의미하게 높게 나타났다. The latest BLOG is highlighted both freely writing about the personal life and the tool which is maintaining friendly relations with many people by trackback. In this study, this BLOG system is designed for improving self-esteem in the class by using these characteristic of BLOG. the internet activity of students and their normal activity in the classroom connects with The Star-Gift-Shop module. This module induces students to an active BLOG, activity with interest. as a result of this activity in the class BLOG system, students improves their computer application ability and confidence of them. Which is effected teacher's efficient classroom management.

韓國 自動車産業의 下請生産과 그 立地에 關한 硏究

柳承翰 동국지리학회 1989 東國地理 Vol.- No.10

A firm operates its economic activity through the complex interaction with other firms. Therefore, to understand modern industrial location, it is crucial that the whole process of locational decision-making is viewed in the context of the interdependence between a firm and its external environment. In this regard, this study examined structure of production subcontracting in the Korean automobile industry, focused on Hyun Dai Motors, Crop., having an interest in spatial interaction and locational pattern of the subcontractor. The results are summarized as follows; First, there is a tendency of the aggregate locational pattern that the subcontractor is located near the parent firm's production facility. However, it is difficult to demonstrate the tendency can apply to all of subcontractors. This study cissified subcontractors into several sub-groups based on their characteristics such as natures of products, scales of subcontracting, and investigated their locational patterns. As a result, each sub-group shows its own locational pattern; subcontractors which producing by press are more closely located to parent firm's production facility than subcontractors which produce electric devices; subcontractors with intense and large subcontracting linkage in scale are more closely located to parent firm's production facility than those small in scale of subcontracting. the spatial variations are due to natures of products, scales of subcontracting, purchasing strategy of parent firm, and historical inertia of auto-parts industry. Second, from the view-point of spatial arrangement of subcontractor, Hyun Dal's subcontractors have/have been concetrated around their parent firm's production site, UlSan. To explain this tendency, four types of industrial movement-new entry, closure, transfer, and establishment of branch plant - are examined and most of spatial concentration is proved to be a consequence of the last two types of movement. Finally, in terms of locational change of subcontractors, parent firm requires subcontractors to move from Ex-UlSan to UlSan and its adjacent region. By the movent of subcontractors to the parent firm's production facility, it is possible for parent firm to minimize inventory cost and to reduce production cost. On the contrary, subcontractors regard stablization of subcontracting relationship and technological assistance from the parent firm as major and important possible advantages. Nevertheless, the obstacles of movement from firm's internal and/or external environment made most subcontractors hardly move to UlSan and its adjacent region. Most crucial factors in these obstacles are identified uncertainity of relationship with the parent firm, small in subcontracting scale, enterpreneurer's personal factors, excessive land values and labor shortage.

Addition of Resection of Temporal Muscle and Fascia in Decompressive Craniectomy in the Treatment of Traumatic Brain Injury

유승한,김병철,최재영,이재일,조원호,최혁진 대한신경손상학회 2016 Korean Journal of Neurotrauma Vol.12 No.2

Objective: Decompressive craniectomy (DC) is a widely used surgical procedure for control of severely increased intracranial pressure in various conditions. The goal of this study is to evaluate the effectiveness of the addition of resection of temporalis muscle and fascia in DC particularly in the treatment of traumatic brain injury. Methods: Twenty patients underwent temporalis muscle and fascia resection in addition to conventional DC and duroplasty due to massive brain swelling in a single tertiary hospital from 2013 to 2015 were enrolled. Twenty other patients who received the standard techniques by other neurosurgeons in the same period were gathered for the control group. Postoperative computed tomography (CT) as well as functional outcome in both groups were analyzed retrospectively. Results: CT volumetry showed a significant increase of 85.19 mL (p<0.001) of extracranial herniation volume in the research group compared with the control group. Using modified Rankin Scale and Glasgow Outcome Scale, there was no statistically significant difference in functional outcome between the two groups. Conclusion: Although preliminary, the procedure appears to show a meaningful increase in extracranial herniation volume with minimal masticatory and cosmetic impairment.

지정토론

유승한 한국금융연구원 2013 韓國經濟의 分析 Vol.19 No.2

본 연구는 우리나라의 소득분배지표의 근간이 되는 통계청의 가계조사방식이 가지고 있는 한계점에 대해 논의하고 소득세 자료를 이용하여 이를 보정할 수 있는 대안을 제시하고 있다. 구체적으로 살펴보면, 가계조사방식은 상위소득자 를 누락하게 되는 문제점과 더불어 누락되지 않은 표본들에서도 과소보고현상이 일관되게 나타나고 있고, 이는 우리나라의 소득불평등도를 과소평가하게 만드는 원인이 될 수 있다는 것을 다각도로 보여주고 있다. 이러한 논의의 가장 대표적 인 사례로 현재의 가계조사방식은 다른 OECD국가와 비교하여 우리나라를 소득 불평등도가 상대적으로 낮은 국가의 하나로 보여주고 있으나, 저자들은 이것이 가계조사방식이 불평등도를 과소평가한 것에 기인한다고 설명하고 있다. 흥미로운 연구로서 최근에 소득집중도와 불평등도의 장기추세를 보기 위해 소득 세자료를 이용한 일련의 중요한 연구들과 관련이 되어 있다. 소득세자료를 이용 하여 소득집중도와 불평등도의 장기추세에 새로운 시각을 제시한 논문들은 Piketty (2001, 2003)가 프랑스의 사례를 연구한 것으로부터 시작되어 Piketty and Saez (2003)의 미국의 사례, Atkinson(2005)의 영국의 사례와 Moriguchi and Saez(2008) 의 일본의 사례로 이어지고 최근에는 세계 각국의 사례를 연구하는 것으로 큰 영향력을 발휘하고 있다(Atkinson, Piketty and Saez(2011)). 본 연구는 한국의 사 례에 소득세 자료를 적용하여 우리나라 소득불평도에 대해 새로운 시각을 제시 하였을 뿐만 아니라 소득세 자료의 문제점을 보완하기 위한 보정방법을 논의한 다. 본 연구의 분석과 관련한 두 가지가 보완되거나 재검토되어야 할 점은 다음과 같다.