• 제목/요약/키워드: internal length scale

검색결과 76건 처리시간 0.022초

단일 비전에서 칼만 필티와 차선 검출 필터를 이용한 모빌 로봇 주행 위치.자세 계측 제어에 관한 연구 (A Study on Measurement and Control of position and pose of Mobile Robot using Ka13nan Filter and using lane detecting filter in monocular Vision)

  • 이용구;송현승;노도환
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.81-81
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    • 2000
  • We use camera to apply human vision system in measurement. To do that, we need to know about camera parameters. The camera parameters are consisted of internal parameters and external parameters. we can fix scale factor&focal length in internal parameters, we can acquire external parameters. And we want to use these parameters in automatically driven vehicle by using camera. When we observe an camera parameters in respect with that the external parameters are important parameters. We can acquire external parameter as fixing focal length&scale factor. To get lane coordinate in image, we propose a lane detection filter. After searching lanes, we can seek vanishing point. And then y-axis seek y-sxis rotation component(${\beta}$). By using these parameter, we can find x-axis translation component(Xo). Before we make stepping motor rotate to be y-axis rotation component(${\beta}$), '0', we estimate image coordinates of lane at (t+1). Using this point, we apply this system to Kalman filter. And then we calculate to new parameters whick make minimum error.

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하지통증을 호소하는 샤르코마리투스 질환 환자에 대한 복합적 한방처치 1례 (A Case Report of a Patient with Charcot-Marie-Tooth Disease Complaining about Lower Limb Pain)

  • 문희영;류광현;추원정;최요섭;박지원;김두리;류원형;전용현
    • 대한한방내과학회지
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    • 제39권6호
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    • pp.1321-1328
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    • 2018
  • Objective: This study was performed to report on the effects of traditional Korean Medicine as a treatment for a patient with Charcot-Marie-Tooth disease, with lower limb pain as the chief complaint. Methods: We treated this patient with traditional Korean medicine and measured symptom severity using the Visual Analogue Scale (VAS), and the Oswestry Disability Index (ODI) as well as measuring the length of the patient's self-exercising time. Results: After about 7 weeks of treatment, most pathological symptoms had decreased. There was a gradual decline in the VAS and a gradual increase in the length of the self-exercising time. Although there was an increase in the ODI scale during the first 2 weeks, it eventually showed a decline in the rest of the period. Conclusions: Traditional Korean medicine can be a solution for the patients with Charcot-Marie-Tooth disease suffering from peripheral neurological symptoms.

병원 간호사의 조직몰입 영향 요인 (Factors Influencing Organizational Commitment among Hospital Nurses)

  • 박금자;김요나
    • 간호행정학회지
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    • 제16권3호
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    • pp.250-258
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    • 2010
  • Purpose: The purpose of this study is to examine the effective factors of organizational commitment among hospital nurses. Method: The subjects were 250 registered nurses working in 3 hospitals in Busan. Data were obtained by self-reported questionnaires from the 10th of June to 30th of June, 2009. Data were analyzed by frequency and percentage, t-test, ANOVA and Sheffe's test and stepwise multiple regression. Result: Mean of job satisfaction was $60.56{\pm}9.25$ (range of scale: 20-100), internal marketing was 69.49 (range of scale: 25-125), job stress obtained $100.60{\pm}17.93$ (range of scale: 45-180), and organizational commitment got $47.78{\pm}6.84$ (range of scale: 15-75). The extent of the organizational commitment had differences according to the age (F=3.300, p=.039), educational level (F=3.21, p=.042), religion (F=3.30, p=.021), position (F=5.837, p=.003), and career length (F=2.642, p=.035). The influencing factors in organizational commitment of hospital nurses were job satisfaction, internal marketing, and age. $R^2$=.503. The job satisfaction has the highest significant predictor of organizational commitment. Conclusion: The influencing factors on organizational commitment were job satisfaction, internal marketing and age. Thus it is needed to improve the job satisfaction and internal marketing of hospitals' nurses and to provide care and support to younger nurses.

대형 축조블록을 이용한 보강토옹벽의 안정성 평가 (Stability evaluation of reinforced earth walls based on large-scale modular blocks)

  • 한중근;김민우;홍기권;윤중만
    • 한국지반신소재학회논문집
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    • 제13권4호
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    • pp.143-151
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    • 2014
  • 본 연구에서는 대형 축조블록과 지오그리드 보강재를 이용한 보강토 옹벽의 안정성을 검토하였으며, 이를 바탕으로 구조물의 적용에 대하여 평가하였다. 안정성은 옹벽높이, 뒤채움 흙의 강도 및 지오그리드 보강재의 강도 조건에 따른 외적 및 내적안정성을 검토하였다. 외적안정성 분석 결과, 보강재의 길이는 전면벽체 저면으로부터 산정된 옹벽높이의 0.7H와 보강재 수직간격을 1m로 설치하였을 때, 뒤채움 흙의 내부마찰각 및 옹벽 높이에 관계없이 모든 해석조건에서 기준안전율을 만족하였다. 내적안정성의 경우에는 뒤채움 흙의 내부마찰각이 $25^{\circ}$인 경우에도 일부 옹벽 높이에서 파단 및 인발에 대한 안정성이 확보할 수 있는 것으로 나타났다. 특히, 내적안정성 평가결과를 바탕으로 대하여 구조적 안정성 및 경제성을 고려할 수 있는 구조물로의 적용이 가능할 것으로 확인되었다.

염화마그네슘 첨가율에 따른 산화마그네슘 경화체의 길이변화 특성 (Shrinkage Strain Property of the Magnesium Oxide Matrix According to Magnesium Chloride Addition Ratio)

  • 정병열;이상수;송하영
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2013년도 추계 학술논문 발표대회
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    • pp.150-151
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    • 2013
  • Recently, the internal space organization of the building changes to the frame construction and flat slab construction in the wall type structure. And the use of light weight panel changing the internal joint use easily is increased. Therefore, in this research, the length change characteristic that the magnesium chloride addition rate reaches to the magnesium curing body tries to be studied. It could confirm according to the length change specific result that the magnesium chloride amount of addition reaches to the magnesium oxide curing body to expand. And the thing described below was the large-scale expansion the magnesium oxide addition rate 60%. And it showed up as 50, 40, 30, 20, and order of 10s (%). It could look at to form the hydrate of the SEM picture result needle-shaped of the Hardened.

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평활화 유한요소법을 도입한 응력기반 구배 탄성론 (A Stress-Based Gradient Elasticity in the Smoothed Finite Element Framework)

  • 이창계
    • 한국전산구조공학회논문집
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    • 제37권3호
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    • pp.187-195
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    • 2024
  • 본 논문에서는 평활화 유한요소법(Smoothed finite element method)을 도입한 응력 기반 구배 탄성론(Gradient elasticity)의 2차원 경계치 문제에 대한 연구를 수행하였다. 구배 탄성론은 기존 탄성론에서는 표현할 수 없는 미소규모의 크기 의존적인 기계적 거동을 설명하기 위해 제안되었다. 구배 탄성체론에서 고차 미분 방정식을 두 개의 2차 미분 방정식으로 분할하는 Ru-Aifantis 이론을 사용하기 때문에 평활화 유한요소법에 적용이 가능하게 된다. 본 연구에서 경계치 문제를 해결하기 위해 평활화 유한 요소 프레임워크에 스태거드 방식(Staggered scheme)을 사용하여 국부 변위장과 비국부 응력장을 평활화 영역 및 요소에서 각각 계산하였다. 구배 탄성에서 중요한 변수인 내부 길이 척도의 영향을 측정하기 위해 일련의 수치 예제를 수행하였다. 수치 해석 결과는 제안한 기법이 내부 길이 척도에 따라 균열 선단과 전위 선에 나타나는 응력 집중을 완화할 수 있음을 보여준다.

Multi-scale heat conduction models with improved equivalent thermal conductivity of TRISO fuel particles for FCM fuel

  • Mouhao Wang;Shanshan Bu;Bing Zhou;Zhenzhong Li;Deqi Chen
    • Nuclear Engineering and Technology
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    • 제55권3호
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    • pp.1140-1151
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    • 2023
  • Fully Ceramic Microencapsulated (FCM) fuel is emerging advanced fuel material for the future nuclear reactors. The fuel pellet in the FCM fuel is composed of matrix and a large number of TRistructural-ISOtopic (TRISO) fuel particles which are randomly dispersed in the SiC matrix. The minimum layer thickness in a TRISO fuel particle is on the order of 10-5 m, and the length of the FCM pellet is on the order of 10-2 m. Hence, the heat transfer in the FCM pellet is a multi-scale phenomenon. In this study, three multi-scale heat conduction models including the Multi-region Layered (ML) model, Multi-region Non-layered (MN) model and Homogeneous model for FCM pellet were constructed. In the ML model, the random distributed TRISO fuel particles and coating layers are completely built. While the TRISO fuel particles with coating layers are homogenized in the MN model and the whole fuel pellet is taken as the homogenous material in the Homogeneous model. Taking the results by the ML model as the benchmark, the abilities of the MN model and Homogenous model to predict the maximum and average temperature were discussed. It was found that the MN model and the Homogenous model greatly underestimate the temperature of TRISO fuel particles. The reason is mainly that the conventional equivalent thermal conductivity (ETC) models do not take the internal heat source into account and are not suitable for the TRISO fuel particle. Then the improved ETCs considering internal heat source were derived. With the improved ETCs, the MN model is able to capture the peak temperature as well as the average temperature at a wide range of the linear powers (165 W/cm~ 415 W/cm) and the packing fractions (20%-50%). With the improved ETCs, the Homogenous model is better to predict the average temperature at different linear powers and packing fractions, and able to predict the peak temperature at high packing fractions (45%-50%).

심리스 튜브 제조공정 시 피어싱 플러그의 파손거동 (Failure Behavior of Piercing Plug during Seamless Tube Manufacturing Process)

  • 임영빈;윤정모
    • 열처리공학회지
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    • 제30권5호
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    • pp.207-214
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    • 2017
  • In this study, failure behavior of piercing plug for seamless tube manufacturing process was studied. Three different kinds of passed piercing plugs (10, 90, 215 times) were prepared. The shape deformation of the passed piercing plugs was observed by 3D coordinate measuring machine, and the oxidized layer on the surface of piercing plug was observed by optical microscopy. The length reduction of piercing plug presented at 215 times passed plug. It was found that the oxidized layer consisted of outer scale, inner scale and internal oxidation layers, and the inner scale layer had vertical cracks, and interfaces had horizontal cracks. We proposed the failure mechanism of piercing plug during seamless tube manufacturing process based on the formation of vertical and horizontal crack.

Study on the progressive collapse resistance of CP-FBSP connections in L-CFST frame structure

  • Xiong, Qingqing;Wu, Wenbo;Zhang, Wang;Chen, Zhihua;Liu, Hongbo;Su, Tiancheng
    • Steel and Composite Structures
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    • 제44권3호
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    • pp.437-450
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    • 2022
  • When the vertical load-bearing members in high-rise structures fail locally, the beam-column joints play an important role in the redistribution of the internal forces. In this paper, a static laboratory test of three full-scale flush flange beam-reinforced connections with side and cover plates (CP-FBSP connection) with double half-span steel beams and single L-shaped columns composed of concrete-filled steel tubes (L-CFST columns) was conducted. The influence of the side plate width and cover plate thickness on the progressive collapse resistance of the substructure was thoroughly analyzed. The failure mode, vertical force-displacement curves, strain variation, reaction force of the pin support and development of internal force in the section with the assumed plastic hinge were discussed. Then, through the verified finite element model, the corresponding analyses of the thickness and length of the side plates, the connecting length between the steel beam flange and cover plate, and the vertical-force eccentricity were carried out. The results show that the failure of all the specimens occurred through the cracking of the beam flange or the cover plate, and the beam chord rotations measured by the test were all greater than 0.085 rad. Increasing the length, thickness and width of the side plates slightly reduced the progressive collapse resistance of the substructures. The vertical-force eccentricity along the beam length reduced the progressive collapse resistance of the substructure. An increase in the connecting length between the beam flange and cover plate can significantly improve the progressive collapse resistance of substructures.

어머니의 격리불안 척도의 개발 (Development of the Maternal Separation Anxiety Scale)

  • 조복희;박성옥
    • 아동학회지
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    • 제13권1호
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    • pp.16-37
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    • 1992
  • The purpose of this study was the development of a scale to assess maternal anxiety after mother-child separation. Subjects consisted of 384 mothers who had children from 6 to .36 months of age. A questionnaire consisting of eighty Likert-type items and Spielberger's(1970) State Anxiety Scale were administered to mothers and data were analyzed using item analysis. factor analysis. multiple regression. Cronbach's ${\alpha}$. Pearson's correlation and F-test. Sixty of the eighty items were significant and deemed acceptible through item discrimination method with indices ranging from. 32 to .95. Factor analytic procedures have selected 54 items of the 60-item scale and supported a 5-factor solution. The subscales labeled 'Maternal Separation Anxiety'. 'Perception of Separation Effects on the Child', 'Desire for Physical Cuddling and Closeness'. 'Attitudes toward the Value or Importance of Exclusive Maternal Care' and 'Employment-related Separation Concerns,' Finally. a multiple regression analysis conducted to reduce the length of the scale yielded a 39-item form for the Maternal Separation Anxiety Scale(MSAS). Internal consistency of the MSAS was high(Cronbach's ${\alpha}$ =.85). The correlation of the MSAS with the Spielberger's State Anxiety measure yielded a coefficient of .36, revealing a moderate and positive relationship.

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