• 제목/요약/키워드: Obstacle factor

검색결과 112건 처리시간 0.028초

Thermal Stability of $MnOx-WO_3-TiO_2$ Catalysts Prepared by the Sol-gel Method for Low-temperature Selective Catalytic Reduction

  • 신병길;이희수
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2011년도 추계학술발표대회
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    • pp.28.2-28.2
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    • 2011
  • The selective catalytic reduction (SCR) of NOx by $NH_3$ is well known as one of the most convenient, efficient, and economical method to prevent NOx emission in flue gas from stationary sources. The degradation of the reactivity is the obstacle for its real application, since high concentrations of sulfur dioxide and thermal factor would deactivate the catalyst. It is necessary to develop high stability of catalysts for low-temperature SCR. Among the transition metal oxides, $WO_3$ is known to exhibit high SCR activity and good thermal stability. The $MnOx-WO_3-TiO_2$ catalysts prepared by sol-gel method with various $WO_3$ contents were investigated for low-temperature SCR. These catalysts were observed in terms of micro-structure and spectroscopy analyses. The $WO_3$ catalyst as a promoter is used to enhance the thermal stability of catalyst since it increases the phase transition temperature of $TiO_2$ support. It was found that the addition of tungsten oxides not only maintained the temperature window of NO conversion but also increased the acid sites of catalyst.

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간호사의 신생아 통증관리 수행에 영향을 미치는 요인 (Factors Influencing Neonate Pain Management Performed by Nurses)

  • 노인숙;오진아
    • Child Health Nursing Research
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    • 제17권3호
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    • pp.190-197
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    • 2011
  • Purpose: The purpose of this study was to identify factors influencing neonatal pain management by nurses in order to provide evidence-based data for the development of more efficient neonatal pain care programs. Methods: This study used a descriptive research design to survey 204 registered nurses working in neonatal intensive care units and nurseries in Busan. Data collection was done from July to September 2010. General knowledge of pain and pain scale, pain intervention, neonatal pain management, and barriers to pain management were measured. Data were analyzed using stepwise multiple regression with SPSS 17.0. Results: it was found that among the factors affecting neonatal pain management by nurses, the unit where the nurse worked was the most important influential factor, followed by knowledge of pain management, education level, and barriers from medical personnel in that order. The explanatory power of these four variables accounted for 42.0% of neonatal pain management. Conclusion: Study results indicate that it is necessary to develop education programs to increase knowledge of neonatal pain management for nurses caring for neonates. Also, plans for reduction of obstacle factors in medical personnel should be prepared.

퍼지-뉴럴 네트워크를 이용한 자율 이동로봇의 운항 (Navigation of Autonomous Mobile Robot using Fuzzy Neural Network)

  • 최정원
    • 조명전기설비학회논문지
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    • 제22권4호
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    • pp.19-25
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    • 2008
  • 본 논문은 장애물에 대한 사전 정보를 가지고 있지 않은 미지의 공간에서 장애물의 회피와 지정된 목표점으로 이동할 수 있는 자율이동로봇을 위한 퍼지-뉴럴 네트워크를 이용한 지능제어 알고리즘을 제안하고, 제안된 제어기의 효용성을 모의실험과 실제 로봇의 구동실험을 통하여 검증을 한다. 제시한 지능제어기는 계층구조의 알고리즘으로 로봇이 목표에 도달하기 위한 퍼지 알고리즘과 주행 중 만날 수 있는 장애물들에 대한 회피를 수행하는 퍼지-뉴럴 알고리즘으로 구성된 계층과, 로봇이 이동하면서 만날 수 있는 여러 가지 상황에 따라 장애물 회피동작과 목표점 도달동작을 수행할 수 있도록 두 알고리즘에 적당한 가중치를 부여하는 가중치 퍼지 알고리즘으로 구성되어 있다. 그리고 로봇의 현재 운동정보와 장애물까지의 거리정보를 바탕으로 가중치 퍼지 알고리즘의 출력부 소속도 함수를 조절함으로서 오목한 장애물에 대해서도 장애물 회피 동작을 수행하도록 하였다. 제작된 로봇으로 제시한 알고리즘의 실효성을 검증하였다.

판별분석을 활용한 주·야간 고속도로 교통사고 영향요인 비교연구 (Discriminant Analysis of Factors Affecting Traffic Accident Severity During Daytime and Nighttime)

  • 김경태;이수범;최지혜;박시내;서금열
    • 한국도로학회논문집
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    • 제18권3호
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    • pp.127-134
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    • 2016
  • PURPOSES : Low visibility caused by dark surroundings at nighttime affects the likelihood of accidents, and various efforts, such as installing road safety facilities, have been made to reduce accidents at night. Despite these efforts, the nighttime severity index (SI) in Korea was higher than the daytime SI during 2011-2014. This study determined the factors affecting daytime and nighttime accident severity through a discriminant analysis. METHODS : Discriminant analysis. RESULTS : First, drowsiness, lack of attention, and lighting facilities affected both daytime and nighttime accident severity. Accidents were found to be caused by a low ability to recognize the driving conditions and a low obstacle avoidance capability. Second, road conditions and speeding affected only the daytime accident severity. Third, failure to maintain a safe distance significantly affected daytime accident severity and nonsignificantly affected nighttime accident severity. The majority of such accidents were caused by rear-end collisions of vehicles driving in the same direction; given the low relative speed difference in such cases, the shock imparted by the accidents was minimal. CONCLUSIONS : Accidents caused by a failure to maintain a safe distance has lower severity than do accidents caused by other factors.

유치원 특성 변인이 $4{\sim}5$세 유아의 운동능력에 미치는 영향 (The Effect of Kindergarten's Factors on Athletic Movement Ability in $4{\sim}5$ Years Old Children)

  • 오연주
    • 한국생활과학회지
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    • 제13권3호
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    • pp.407-415
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    • 2004
  • The purpose of this study was to investigate the effect of kindergarten's factors on athletic movement ability in early childhood. The factors included teacher's perception of athletic movement, length of time for physical activity, and number of athletic facilities in the kindergarten. The subjects consisted of 551 children aged from four to five years in 8 private kindergartens. The instruments used for this study were the obstacle course of Project Spectrum for measuring athletic movement ability, and the questionnaire to investigate the teacher's perception, length of time for physical activity, and number of athletic facilities in the kindergarten. The data from all the tests were analyzed by correlation and regression analyses. The results of this study exhibited that the length of time for physical activity was the most important factor among three factors, and the teachers' perception of athletic movement and the number of athletic facilities in the kindergarten were also deciding factors for the children's athletic movement ability.

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로봇팔의 장애물 중에서의 시간 최소화 궤도 계획 (Minimum-Time Trajectory Planning for a Robot Manipulator amid Obstacles)

  • 박종근
    • 한국정밀공학회지
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    • 제15권1호
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    • pp.78-86
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    • 1998
  • This paper presents a numerical method of the minimum-time trajectory planning for a robot manipulator amid obstacles. Each joint displacement is represented by the linear combination of the finite-term quintic B-splines which are the known functions of the path parameter. The time is represented by the linear function of the same path parameter. Since the geometric path is not fixed and the time is linear to the path parameter, the coefficients of the splines and the time-scale factor span a finite-dimensional vector space, a point in which uniquely represents the manipulator motion. The displacement, the velocity and the acceleration conditions at the starting and the goal positions are transformed into the linear equality constraints on the coefficients of the splines, which reduce the dimension of the vector space. The optimization is performed in the reduced vector space using nonlinear programming. The total moving time is the main performance index which should be minimized. The constraints on the actuator forces and that of the obstacle-avoidance, together with sufficiently large weighting coefficients, are included in the augmented performance index. In the numerical implementation, the minimum-time motion is obtained for a planar 3-1ink manipulator amid several rectangular obstacles without simplifying any dynamic or geometric models.

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시공단계에서의 BIM 활용성 증대를 위한 품질관리 방안 (Quality Management for Utilizing BIM in Construction Phase)

  • 권오철;조주원;조찬원
    • 한국CDE학회논문집
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    • 제18권5호
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    • pp.338-347
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    • 2013
  • Since it is common that design BIM data created by designers and engineers do not afford to consider constructability for the site, it is usually necessary to optimize the design BIM data to construction BIM data. While this optimization process requires various design updates depending on the construction methods and requirements, most designers in the projects do not participate the construction phase, which can arise another obstacle factor in utilizing construction BIM. In order to prevent this issue, we need cooperation system, where all the parties work together from the initial stage of project to create quality assured BIM model. However this kind of system is not realistic in Korea with most of the working processes being conventional yet. Therefore, at this point of time, it is realistic for us to secure basic construction qualities in the design phase and keep those qualities by the construction phase. This study suggested a relevant quality management plan for BIM usage in construction phase.

간질(癎疾)의 원인(原因)에 대한 동서의학적(東西醫學的) 고찰(考察) (The investigation into the cause of epilepsy between east and west medicine)

  • 박지은;권정남;김영균
    • 대한한방내과학회지
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    • 제20권1호
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    • pp.33-47
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    • 1999
  • Through a literal study upon the cause of epilepsy between east and west medicine, next conclusion have been abtained. 1. The cause epilepsy in the east medicine, congenital embryo disease is due to insufficiency of heart(心虛) or deficiency of heart energy(心氣虛), secondary cause is wind -evil(風), frightness(驚), phlegm(痰), fire(火) 2. The cause epilepsy in the west medicine is divided congenital disease and secondary cause, one is excessive discharge of electricity of the brain have on a central nerve, a digestive organ, a respiratory organ, hamatogenous functions, the other is hereditary it and pathological it. 3. The epilepsy is concerned about the abnormality in five viscera, liver, spleen, heart. 4. In comparison east and west medicine of epilepsy is native factor, or innate primary cause is added to outer cause of wind-evil(風), cold-evil(寒), summer-heat(署), wetness(濕), and inner cause of frightness-terror(驚-恐), seven modes of emotions(七情) and the epilepsy is occurred phlegm(痰), fire(火). It similar that the epilepsy is occurred to structural and functional obstacle in western hereditary and primary cause.

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다목적 야외경기장의 음향특성에 관한 연구 II -서울월드컵 경기장의 전기음향시스템고찰과 음향측정을 중심으로- (The Properties of Acoustic in Multi-purpose out-door Stadium II - a case study of seoul world cup stadium measurement -)

  • 김정중;손장열
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 춘계학술대회논문집
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    • pp.731-739
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    • 2002
  • recently out door stadiums have been built as multi purpose stadium for athletic sports It hold but also various events and huge concerts. in the past, out-door stadium usually was built, but recently the out-door stadium which of the 50 % of roof covered by doom have been built increasingly. as the result, the sound obstacle is becoming very important. but a design of sound has become unplaned except some of the stadium, also rarely been built by sound-absorption material. as the result, the purpose of this study is investigating, analyzing the theory for plan of electric acoustic sound, a drawing of acoustic design and measurement a result value, comparison, evaluating a main sound factor with criteria of the Seoul City design. and reservation time, clearness, sound pressure level suitable for using purpose, so the necessary quantities will be added to financial budget of building acoustic design. and For verification, this contains acoustic analyser measurement and computer simulation and this study will find the solution of helping method.

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중산층 이상 가족이 인식하는 치매노인 그룹흠의 장점과 국내 도입의 문제점 (Merits of this Group Homes far the Elderly with Dementia Recognized by Middle and Upper Class Families, and Potential Obstacles to its Introduction in Korea)

  • 김대년;권오정;최정선
    • 가정과삶의질연구
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    • 제19권6호
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    • pp.113-128
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    • 2001
  • middle and upper class families, and examine obstacles to their introduction in Korea. Since a few large-scale facilities for the elderly with dementia have been provided for only low-income families free of charge, the necessity of group homes for middle and upper class families willing to pay for such services has become an issue recently in order to lessen the burden on families, as well as to promote the well-being of the dementia victims themselves. The survey was conducted by questionnaires collected from 577 respondents from middle and upper class families. The results of the survey were as follows: The merits of the group homes were 1)decreasing loneliness of the elderly, 2)providing active and stimulating environments allowing for participation everyday life activities, and 3)lessening the emotional and physical burden on the caring families. Potential obstacles to its introduction in Korea were 1)the difficulty of finding sites to build the group home because of the negative perception of people with disabilities and a NIMBY(Not In My Back Yard) reaction to the construction of it and 2)the economic burden on the caring family. Surprisingly, the guilt factor associated with sending the parents into group homes was not considered as a big obstacle. Referring to results of this study, it is asserted that group homes for the elderly with dementia would be embraced throughout the country if Koreans could have the chance to understand what group homes are.

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