• 제목/요약/키워드: kinetic system

검색결과 946건 처리시간 0.024초

동적가족화에 의한 청소년의 가족지각과 가족체계와의 관련성 연구 -Minuchin의 구조적 가족치료 이론에 기초하여- (Family Perception of Adolescence Through the Kinetic Family Drawing(KFD), And Relation with Family System -On the basis of Minuchin's Structural Family Therapy Theory-)

  • 이미옥
    • 대한가정학회지
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    • 제42권5호
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    • pp.145-160
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    • 2004
  • The purpose of this study was to explore family perception of adolescence through the Kinetic Family Drawing (KFD), and to explore its relation with the family system. The Kinetic Family Drawing (KFD) and Family System Diagnosis Scale (FSDS) were administered to 356 adolescent children. Data were analyzed using the regression analysis and the discriminant analysis. The results were as follows: First, there was a significant difference among the KFD family adaptability variables of boys' KFD and the flexibility and rigidity variables of the FSDS in the family relationship. For example, That is; for sons', it means that if there is a greater the satisfaction for their family in their drawings, then the family relationship will be more flexible. Especially with the son's KFD, there was an indication that if there is a greater the activity level of the self, then he has more flexibility in his family relationship. Second, there is a significant difference in the relationship between the KFD family hierarchy variables of girls' KFD and the parent coalition·cross-generational triads variable of the FSDS. For girls 'KFD, the result of this study indicated that when there is a greater the distance between the father figure and the child figure, the cross-generational triads we greater.

대형 자동차 하이브리드 유압 구동시스템의 회로구성과 특성해석에 관한 연구 (A Study on the Circuit Composition and Characteristics Analysis for Heavy-Duty Vehicular Hybrid Hydraulic Driving System)

  • 이재구;이재천;한문식
    • 한국자동차공학회논문집
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    • 제12권2호
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    • pp.197-204
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    • 2004
  • An accumulator in hydraulic systems stores kinetic energy during braking action, and then that controls hasty surge pressure. An energy recovery system using accumulator seems to be advantageous for ERBS due to its high energy density. This study suggests a method to decide suitable accumulator volume for ERBS. The method is based upon energy conservation between kinetic energy of moving inertia and elastic energy of accumulator. The energy conversion was analyzed and a simple formula was derived. Also accumulator tests were conducted for different load mass and motor speed. A series of test work were carried out in the laboratory and the dynamic characteristics of the hydraulic motor system, such as the surge pressure and response time, were investigated in both brake action and acceleration action and these results show that the proposed design is effective for decision accumulator volume in ERBS.

틸팅 부하메커니즘 특성 분석을 위한 유압식 부하특성 평가 장치구성에 대한 연구 (A Study on a Configuration of the Load Characteristic Evaluation Device Using Hydraulic Power for the Analysis of the Tilting Kinetic Mechanism)

  • 이준호;김호연;한성호
    • 한국소음진동공학회논문집
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    • 제21권12호
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    • pp.1152-1158
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    • 2011
  • In this paper a configuration of the load evaluation device for the tilting actuator using hydraulic power is presented, which makes it possible to measure the force action on the tilting actuator. It is possible to measure only current using the conventional electro-mechanical actuator when the bogie is in the process of the tilting. This makes impossible to measure the force acting on the tilting actuator. In order to overcome this problem a kinetic mechanism test system using hydraulic cylinder is proposed. The system are consisted of hydraulic cylinder for the tilting actuation, control system to control hydraulic power, sensors to measure for force and displacement and monitoring system for the user interface.

선반주축계의 동특성 향상에 관한 연구 -주축대와 베드의 보울트 결합을 중심으로- (A Study on the Improvement of Dynamic Characteristics of Spindle-Work System in Lathe - Focused on the Bolt Juint between Headstock and Bed -)

  • 신용호;박태원;홍동표;정인성
    • 대한기계학회논문집
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    • 제12권1호
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    • pp.1-7
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    • 1988
  • 본 연구에서는 컬럼모델을 보울트로 고정할 때 접합면에 알루미늄판, 황동판, 스테인리스판 등을 삽입하고 정적강성과 동적특성을 검토하여 이것을 기초로 공작물- 주축대-공구로 형성되고 있는 사이클중에서 선반의 주축대와 베드를 연결하는 결합부에 모델실험을 사용한 게재물을 삽입하고 선반구축계의 동적특성을 검토하였다.

부분 구조합성법을 이용한 대형구조물의 동특성 규명 및 개선에 관한 연구 (A Study on the Identification and Improvement of Dynamic Characteristics of Large Structure by Component Mode Synthesis Method)

  • 오재응;이정환;임동규
    • 소음진동
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    • 제4권3호
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    • pp.327-335
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    • 1994
  • In this paper, to identify the dynamic characteristics of antenna system, the antenna is divided into 4 components and those were analyzed with a conventional FEM package MSC/NASTRAN. Using a Component Mode Synthesis Method, dynamic characteristics of total system is also identified. The Coherence of each component to total system is evaluated by using strain and kinetic component to total system is evaluated by using strain and kinetic energy. The improving strategy of dynamic characteristics is suggested by changing mass and stiffness of large coherence components.

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MATHEMATICAL MODELLING FOR THE AXIALLY MOVING PLATE WITH INTERNAL TIME DELAY

  • Kim, Daewook
    • East Asian mathematical journal
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    • 제37권5호
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    • pp.619-626
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    • 2021
  • In [1, 2], we studied the string-like system with time-varying delay. Unlike the string system, the plate system must consider both longitudinal and transverse strains. First, we consider the physical phenomenon of an axially moving plate concerning kinetic energy, potential energy, and work dones. By the energy conservation law in physics, we have a nonlinear plate-like system with internal time delay.

정속가열(定速加熱)조건에서 표준온도상당시간(相當時間)을 이용한 비효소적 갈색화 반응의 동력학 파라미터 추정(推定) (Estimation of Kinetic Parameters of Nonenzymatic Browning Reaction Using Equivalent Time at Reference Temperarture with Linearly Increasing Temperature Profile)

  • 조형용;권윤중;김인규;변유량
    • 한국식품과학회지
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    • 제25권2호
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    • pp.178-184
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    • 1993
  • 식품의 품질변화에 미치는 온도의 영향을 분석하기 위한 kinetic parameters를 추정하는데 있어서 표준온도 상당시간이 유효함을 밝히기 위하여 비효소적 갈색반응 액체 모델 및 식품시스템을 직선적으로 온도를 증가시키는 조건$(6^{\circ}\;/h)$에서 반응시켰다. 표준온도 상당시간은 $t_E=-{\exp}[-(E_a/R)\;(1/T-1/T_{ref})]$로 정의되며, 임의의 온도 T에서 1일 동안에 일어난 품질변화는 표준온도 $T_{ref}$에서 몇일 동안에 일어난 변화에 상당하는가를 의미한다. 이와 같이 정의되는 표준온도 상당시간을 이용하여 glucose-lysine모델, 여러종류의 아미노산과 당의 액체모델 및 액체 음료 식품시스템의 실험자료로부터 비선형 최소자승법으로 kinetic parameter, n, $k_{ref}$$E_a$를 추정하였다. Glucose와 lysine의 손실속도는 1차 반응, 갈색물질 형성속도는 0차 반응이었다. 추정한 kinetic parameters를 이용하여 computer simulation한 결과 실험값과의 상관계수가 0.96 이상으로 잘 일치하여 $t_E$를 이용한 1단계 비선형 최소자승법으로 kinetic parameters를 효율적으로 정확히 추정할 수 있음을 확인하였다.

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구조물의 운동 에너지 원리에 의한 감지기의 최적 위치 (Optimal Transducer Placement Based on Kinetic Energy of the Structural System)

  • 황충열;허광희
    • 한국구조물진단유지관리공학회 논문집
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    • 제1권2호
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    • pp.87-94
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    • 1997
  • This research aims to develop an algorithm of optimal transducer placement using Kinetic Energy of the structural system. The structural vibration response-based health monitoring is considered one of the best for the system which requires a long-term, continuous monitoring. In its experimental modal testing, however, it is difficult to decide on the measurement locations and their number, especially for complex structures, which have a major influence on the quality of the results. In order to minimize the number of sensing operations and optimize the transducer location while maximizing the accuracy of results, this paper discusses about an optimum transducer placement criterion suitable for the identification of structural damage. As a criterion algorithm, it proposes the Kinetic Energy Optimization Technique (EOT), and then addresses the numerical issues which are subsequently applicable to actual experiment where a bridge model is used. By using the experimental data, it compares the EOT with the EIM (Effective Independence Method) which is generally used to optimize the transducer placement for the damage identification and control purposes. The comparison conclusively shows that the EOT algorithm proposed in this paper is preferable when a structure is to be instrumented with fewer sensors.

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Effect of Kinetic Parameters on Simultaneous Ramp Reactivity Insertion Plus Beam Tube Flooding Accident in a Typical Low Enriched U3Si2-Al Fuel-Based Material Testing Reactor-Type Research Reactor

  • Nasir, Rubina;Mirza, Sikander M.;Mirza, Nasir M.
    • Nuclear Engineering and Technology
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    • 제49권4호
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    • pp.700-709
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    • 2017
  • This work looks at the effect of changes in kinetic parameters on simultaneous reactivity insertions and beam tube flooding in a typical material testing reactor-type research reactor with low enriched high density ($U_3Si_2-Al$) fuel. Using a modified PARET code, various ramp reactivity insertions (from $0.1/0.5 s to $1.3/0.5 s) plus beam tube flooding ($0.5/0.25 s) accidents under uncontrolled conditions were analyzed to find their effects on peak power, net reactivity, and temperature. Then, the effects of changes in kinetic parameters including the Doppler coefficient, prompt neutron lifetime, and delayed neutron fractions on simultaneous reactivity insertion and beam tube flooding accidents were analyzed. Results show that the power peak values are significantly sensitive to the Doppler coefficient of the system in coupled accidents. The material testing reactor-type system under such a coupled accident is not very sensitive to changes in the prompt neutron life time; the core under such a coupled transient is not very sensitive to changes in the effective delayed neutron fraction.

운동 양자 체(Kinetic Quantum Sieving) 효과를 가진 나노다공성 물질을 활용한 수소동위원소 분리 동향 (Research Trend of Crystalline Porous Materials for Hydrogen Isotope Separation via Kinetic Quantum Sieving)

  • 이슬지;오현철
    • 한국재료학회지
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    • 제31권8호
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    • pp.465-470
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    • 2021
  • Deuterium is a crucial clean energy source required for nuclear fusion and is a future resource needed in various industries and scientific fields. However, it is not easy to enrich deuterium because the proportion of deuterium in the hydrogen mixture is scarce, at approximately 0.016 %. Furthermore, the physical and chemical properties of the hydrogen mixture and deuterium are very similar. Therefore, the efficient separation of deuterium from hydrogen mixtures is often a significant challenge when using modern separation technologies. Recently, to effectively separate deuterium, studies utilizing the 'Kinetic Quantum Sieving Effect (KQS)' of porous materials are increasing. Therefore, in this review, two different strategies have been discussed for improving KQS efficiency for hydrogen isotope separation performance using nanoporous materials. One is the gating effect, which precisely controls the aperture locally by adjusting the temperature and pressure. The second is the breathing phenomenon, utilizing the volume change of the structure from closed system to open system. It has been reported that efficient hydrogen isotope separation is possible using these two methods, and each of these effects is described in detail in this review. In addition, a specific-isotope responsive system (e.g., 2nd breathing effect in MIL-53) has recently been discovered and is described here as well.