• 제목/요약/키워드: Dynamic Compliance

검색결과 167건 처리시간 0.025초

Dynamic Response of Blade Surface Cavitation

  • Toyoshima, Masakazu;Sakaguchi, Kimiya;Tsubouchi, Kota;Horiguchi, Hironori;Sugiyama, Kazuyasu
    • International Journal of Fluid Machinery and Systems
    • /
    • 제9권2호
    • /
    • pp.160-168
    • /
    • 2016
  • In high speed turbopumps, cavitation occurs and often causes the flow instabilities such as cavitation surge and rotating cavitation. The occurrence of these cavitation instabilities is considered to relate to dynamic characteristics of the cavitation, which are modelled using a cavitation compliance and a mass flow gain factor. Various types of cavitation such as a blade surface cavitation, a tip leakage vortex cavitation, and a backflow vortex cavitation occur at the same time in the inducer and the dynamic characteristics of each cavitation have not been clarified yet in experiments. Focusing on the blade surface cavitation as one of fundamental cavitation, we investigated the dynamic characteristics of the blade surface cavitation on a flat plate hydrofoil in experiments in the present study.

굽힘곡선을 이용한 공작기계 주축의 정적 동적 취약부 규명 (Static and Dynamic Weak Point Analysis of Spindle Systems Using Bending Curve)

  • 이찬홍;이후상
    • 한국정밀공학회지
    • /
    • 제15권12호
    • /
    • pp.188-193
    • /
    • 1998
  • This paper describes static and dynamic weak point analysis of spindle systems to eliminate high concentrated bending point on spindle and improve total stiffness of spindle systems. The weak point analysis is based on the evaluation of bending curves of spindles. For static weak point analysis the bending curve is derived from static deflection curve and for dynamic weak point analysis it is derived from the mode shape curves in consideration of the transfer function at exciting point. The validity of the weak point search methodology is verified by comparison of the static deflection, the natural frequency and the dynamic compliance between the original and the improved spindle.

  • PDF

Artificial Muscle Actuator for Robotic Applications

  • Park, Hyoukryeol;Kwangmok Jung;Sungmoo Ryew;Kim, Hunmo;Jaewook Jeon;Jaedo Nam
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2002년도 ICCAS
    • /
    • pp.36.1-36
    • /
    • 2002
  • $\textbullet$ Actuator based on dielelectric elastomer $\textbullet$ Antagonistic configuration $\textbullet$ Musclelike characteristics $\textbullet$ Quasi-static and dynamic analysis $\textbullet$ Compliance control $\textbullet$ Robotic actuators

  • PDF

기관 내 흡인 유형이 인공호흡기 대상자의 폐기능과 저산소혈증에 미치는 효과 (Effects of Open or Closed Suctioning on Lung Dynamics and Hypoxemia in Mechanically Ventilated Patients)

  • 이은영;김수현
    • 대한간호학회지
    • /
    • 제44권2호
    • /
    • pp.149-158
    • /
    • 2014
  • Purpose: This study was conducted to compare effects of open and closed suctioning methods on lung dynamics (dynamic compliance, tidal volume, and airway resistance) and hypoxemia (oxygen saturation and heart rate) in mechanically ventilated patients. Methods: This study was a cross-over repeated design. Participants were 21 adult patients being treated with endotracheal intubation using a pressure-controlled ventilator below Fraction of Inspired Oxygen ($FiO_2$) 60% and PEEP $8cmH_2O$. Data were collected at baseline and 1, 2, 3, 4, 5, and 10 minutes after suctioning. Data were analyzed using two-factor ANOVA with repeated measures on time and suctioning type. Results: Effects of the interaction between suction type and time were significant for oxygen saturation and heart rate but not significant for dynamic compliance, tidal volume, or airway resistance. Prior to performance of suctioning, tidal volume and oxygen saturation were significantly lower, but airway pressure and heart rate were significantly higher using the closed suctioning method as compared with the open suctioning method. Conclusion: For patients on ventilator therapy below $FiO_2$ 60% and PEEP $8cmH_2O$, open suctioning performed after delivery of 100% $FiO_2$ using a mechanical ventilator may not have as much negative impact on lung dynamics and hypoxemia as closed suctioning.

Charpy 충격시편을 이용한 압력용기 재료의 파괴인성 측정 (Evaluation of Fracture Toughness of Pressure Vessel Steel Using Charpy Impact Test Specimens)

  • Han, Dae-June;Park, Sun-Pil
    • Nuclear Engineering and Technology
    • /
    • 제19권1호
    • /
    • pp.1-9
    • /
    • 1987
  • 원자로 압력용기 재료인 SA 533 Grade B Class 1강의 파괴인성에 대하여 -4$0^{\circ}C$~288$^{\circ}C$의 온도 구간에서 Charpy 충격시편을 이용하여 연구하였다. 동적 파괴인성은 계장화 충격시험으로, 정적 파괴인성은 unloading compliance 방법에 따라 3-point bend test로 수행되었으며, 결과는 큰 시편에 의한 자료와 비교하였다. 온도에 대한 재료의 적절한 파괴인성치(하한값)는 천이온도 이상에서는 정직 파괴인성을, 그 이하의 온도에서는 동적 파괴인성을 택함으로써 유추할 수 있음을 알게 되었으며 side-groove가 14%이상일 때 시험은 ASTM E 813의 조건을 만족함을 보였다.

  • PDF

Future Challenges and Perspectives of Digital Dance Interventions for Depression in Older Adults

  • Zhiting Zhang;Qingfeng Zhang
    • International Journal of Advanced Culture Technology
    • /
    • 제12권2호
    • /
    • pp.72-89
    • /
    • 2024
  • Depression is a common disorder among the elderly, significantly affecting their quality of life. Traditional dance interventions, although beneficial, have limitations in convenience, personalization, and retention. With the advent of digital technology, digital dance interventions have emerged as a potential solution to these limitations. This paper involves an extensive review of literature on digital dance interventions. Research databases were searched for studies that focus on the use of digital dance in treating depression among older adults. The review also includes analyses of the advancements in digital dance technology, its application in therapeutic settings, and the evaluation of its efficacy. The paper identifies three main challenges in the current digital dance intervention research: real-time dynamic assessment, multimodal dance generation, and improving compliance. Despite these challenges, digital dance interventions show promise in addressing the limitations of traditional dance therapy. The research suggests that the integration of human-computer interaction and personalized approaches in digital dance interventions could significantly improve outcomes in elderly patients with depression. Digital dance interventions represent a novel and promising approach to treating depression in older adults. Future research should focus on overcoming the identified challenges and enhancing the effectiveness of these interventions.

선형 모터의 동특성 분석 (Analysis of the Dynamic Characteristics of the Linear Motors)

  • 설진수;임경화
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2005년도 춘계학술대회논문집
    • /
    • pp.258-263
    • /
    • 2005
  • The nearest variety of the industrial world requires using the high precision and resolution positioning technology to do a semi-conductor, information field , and measurement field. It is especially important for the positioning technology that makes up a proper controller, is affected by the minimal heat and vibration, and can control a structurally generated non-linear friction factor to determine the efficiency of the system. The paper is to analyze the vibration characteristic according to the speed of linear motor and grasp the dynamic characteristic through the modal test and show the verification of the experimental result and design parameters by using FEM(Finite Element Method). Also, it shows the optimum standard analyzed the acceleration patterns of the moving part that lead to the vibration source in linear motor. It presents the analyzed dynamic of linear motor in compliance with a change of the non-linear factor.

  • PDF

POGO와 PSD의 소개 (Review of POGO and PSD)

  • 고광웅;이한주;정동운;이상용
    • 한국추진공학회지
    • /
    • 제7권4호
    • /
    • pp.1-9
    • /
    • 2003
  • 액체 로켓 시스템에 있어서 주 구조물과 연료 공급 장치의 상호작용 효과에 기인하여 발생하는 POGO라 불리는 축방향 동적 불안정 현상을 억제하기 위하여 몇 가지 종류의 PSD라 불리는 장치가 연구되고 있다. 본 연구에서는 기존에 사용된 PSD의 형태를 살펴보았다. PSD 장치는 수동적 PSD와 능동적 PSD 두 가지 그룹으로 분류할 수 있다. 수동적 PSD는 다시 컴플라이언스의 분포 방식에 따라 집중형과 분산형의 두 가지로 세분할 수 있다 현재까지 개발된 PSD 장치에 대한 포괄적인 검토를 통해, 기체 채움 수위조절 방식의 완충기가 연료 공급 장치의 성능을 저하시키지 않고 POGO 불안정성을 억제할 수 있는 최적의 PSD임을 잠정적으로 제안하였다.

유전성 고분자를 이용한 생체모방형 구동기 (Biomimetic Actuator Based on Dielectric Polymer)

  • 정광목;류성무;구익모;전재욱;구자춘;남재도;이영관;최혁렬
    • 제어로봇시스템학회논문지
    • /
    • 제10권12호
    • /
    • pp.1271-1279
    • /
    • 2004
  • A new bio-mimetic actuator is proposed. The actuator realizes bidirectional actuation since it is with a stretched film antagonistically configured with compliant electrodes. Also, it is distinguished from existing actuators with respect to the controllability of its compliance. Bidirectional actuation and compliance controllability are important characteristics for the artificial muscle actuator and the proposed one accomplishes these requirements without any mechanical substitute or complicated algorithms. In this paper its basic concepts and working principles are introduced with static and dynamic analysis. Control strategies for displacement as well as stiffness are introduced and experimental results are given to confirm the effectiveness of the proposed methods. In addition, an example of robotic actuating devices is given to confirm the usefulness of the proposed actuator.