• 제목/요약/키워드: Passive design method

검색결과 373건 처리시간 0.027초

Acute effect of self-myofascial release using a foam roller on the plantar fascia on hamstring and lumbar spine superficial back line flexibility

  • Do, Kwangsun;Kim, Jaeeun;Yim, Jongeun
    • Physical Therapy Rehabilitation Science
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    • 제7권1호
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    • pp.35-40
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    • 2018
  • Objective: The purpose of this study was to investigate the immediate effect of applying self-myofascial release (SMR) to the plantar fascia using a foam roller on hamstring and lumbar spine superficial back line (SBL). Design: Randomized controlled trial. Methods: Thirty-one healthy adults agreed to the method and purpose of the study. Selection and exclusion criteria were screened, and baseline measurements for the Toe Touch test and passive straight leg raise (PSLR) test were obtained. The participants were then randomly assigned to the SMR group or the sham group. After group assignment, the SMR group rolled the surface of the foot from the heel to the metatarsal head using a foam roller for 5 minutes. The sham group received passive mobilization of the ankle joint in the supine position. Afterwards, the Toe Touch test and the passive straight leg-raise test were re-assessed. Results: In the SMR group, the Toe Touch test results showed significant improvement (p<0.05). Left and right PSLR test results showed a significant increase (p<0.05). In the sham group, there was no significant difference between pre and post-test results. The SMR group showed a significant difference in the PSLR test and Toe Touch test compared to the sham group (p<0.05). Conclusions: The results of this study showed that SMR on the plantar fascia was immediately effective for improving the flexibility of the SBL of the lumbar spine and hamstring.

Overview of separate effect and integral system tests on the passive containment cooling system of SMART100

  • Jin-Hwa Yang;Tae-Hwan Ahn;Hong Hyun Son;Jin Su Kwon;Hwang Bae;Hyun-Sik Park;Kyoung-Ho Kang
    • Nuclear Engineering and Technology
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    • 제56권3호
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    • pp.1066-1080
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    • 2024
  • SMART100 has a containment pressure and radioactivity suppression system (CPRSS) for passive containment cooling system (PCCS). This prevents overheating and over-pressurization of a containment through direct contact condensation in an in-containment refueling water storage tank (IRWST) and wall condensation in a CPRSS heat exchanger (CHX) in an emergency cool-down tank (ECT). The Korea Atomic Energy Research Institute (KAERI) constructed scaled-down test facilities, SISTA1 and SISTA2, for the thermal-hydraulic validation of the SMART100 CPRSS. Three separate effect tests were performed using SISTA1 to confirm the heat removal characteristics of SMART100 CPRSS. When the low mass flux steam with or without non-condensable gas is released into an IRWST, the conditions for mitigation of the chugging phenomenon were identified, and the physical variables were quantified by the 3D reconstruction method. The local behavior of the non-condensable gas was measured after condensation inside heat exchanger using a traverse system. Stratification of non-condensable gas occurred in large tank of the natural circulation loop. SISTA2 was used to simulate a small break loss-of-coolant accident (SBLCOA) transient. Since the test apparatus was a metal tank, compensations of initial heat transfer to the material and effect of heat loss during long-term operation were important for simulating cooling performance of SMART100 CPRSS. The pressure of SMART100 CPRSS was maintained below the design limit for 3 days even under sufficiently conservative conditions of an SBLOCA transient.

Design and Implementation of UAV System for Autonomous Tracking

  • Cho, Eunsung;Ryoo, Intae
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권2호
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    • pp.829-842
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    • 2018
  • Unmanned Aerial Vehicle (UAV) is diversely utilized in our lives such as daily hobbies, specialized video image taking and disaster prevention activities. New ways of UAV application have been explored recently such as UAV-based delivery. However, most UAV systems are being utilized in a passive form such as real-time video image monitoring, filmed image ground analysis and storage. For more proactive UAV utilization, there should be higher-performance UAV and large-capacity memory than those presently utilized. Against this backdrop, this study described the general matters on proactive software platform and high-performance UAV hardware for real-time target tracking; implemented research on its design and implementation, and described its implementation method. Moreover, in its established platform, this study measured and analyzed the core-specific CPU consumption.

High Efficiency Soft-Switching Boost Converter Using a Single Switch

  • Kim, Jun-Ho;Jung, Doo-Yong;Park, Sang-Hoon;Won, Chung-Yuen;Jung, Yong-Chae;Lee, Su-Won
    • Journal of Power Electronics
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    • 제9권6호
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    • pp.929-939
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    • 2009
  • This paper presents a new soft-switching boost converter based on the LC resonance and passive clamping technique without additional active switches. The circuit achieves high efficiency and low voltage stress by adopting a soft switching method using LC resonance. This paper gives a mathematical analysis of each mode and a detailed design procedure of the proposed boost converter. First of all, the operational principles are verified through simulation results. Then, according to the design procedure, we designed and built a 1.5[kW] prototype soft switching boost converter. Through the experimental results, we demonstrated the validity and usefulness of the proposed boost converter.

압전재료와 점탄성 재료를 이용한 지능 적층보의 하이브리드 진동 제어 (Hybrid vibration control of smart laminated composite beams using piezoelectric and viscoelastic material)

  • 강영규;김재환;최승복
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 춘계학술대회논문집
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    • pp.133-137
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    • 2001
  • Active control of flexural vibrations of smart laminated composite beams has been carried out using piezoceramic sensor/actuator and viscoelastic material. The beams with passive constrained-layer damping have been analyzed by formulating the equations of motion through the use of extended Hamilton's principle. The dynamic characteristics such as damping ratio and modal damping of the beam are calculated for various fiber orientations by means of iterative complex eigensolution method, This paper addresses a design strategy of laminated composite under flexural vibrations to design structure with maximum possible damping capacity.

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능동구속감쇠 기법을 이용한 보의 진동제어 실험 (Experiment on Vibration Control of Beam Using Active Constrained-Layer Damping Treatment)

  • 강영규;최진영;김재환
    • 한국소음진동공학회논문집
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    • 제11권4호
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    • pp.52-57
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    • 2001
  • The flexural vibration of aluminum beams with active and passive constrained-layer damping has been investigated experimentally to design a structure with maximum possible damping capacity. Piezoelectric film is used as a sensor and piezoceramic as an actuator for the negative velocity feedback control. The experimental results are compared with those by the finite element analysis. This paper shows the effectiveness of active constrained-layer damping treatment through experiments, and we have carried out an experiment to study the effect of beam thickness.

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수동화 기법에 의한 비정방 선형 시스템의 강인 제어기 설계 (Robust Controller Design for Non-square Linear Systems Using a Passivation Approach)

  • 손영익
    • 제어로봇시스템학회논문지
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    • 제8권11호
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    • pp.907-915
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    • 2002
  • We present a state-space approach to design a passivity-based dynamic output feedback control of a finite collection of non-square linear systems. We first determine a squaring gain matrix and an additional dynamics that is connected to the systems in a feedforward way, then a static passivating (i.e. rendering passive) control law is designed. Consequently, the actual feedback controller will be the static control law combined with the feedforward dynamics. A necessary and sufficient condition for the existence of the parallel feedfornward compensator (PFC) is given by the static output feedback fomulation, which enables to utilize linear matrix inequality (LMI). The effectiveness of the proposed method is illustrated by some examples including the systems which can be stabilized by the proprotional-derivative (PD) control law.

Relation between Game Motivation and Preference to Cutscenes

  • 완소음;조동민
    • 만화애니메이션 연구
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    • 통권36호
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    • pp.573-592
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    • 2014
  • Following rapid development of software and hardware technologies and increasing enhancement in arithmetic capability, there are more and more content that can be accommodated and processed in video games, which is also increasingly complex and fine. Cutscene as a main narrative method have been developed, which have become necessary to express some key plots and important scenarios in games. Good cutscene can strengthen engagement of players with virtual world in games and make players share affection and sorrow with roles in games; while badly-designed cut-scene or overused cut-scene will impair immersion of players and affect players' gaming experience; for this reason, developers should not continue cut-scene design just from opinions of designers nor make players passive receivers, instead, they should reduce as much as possible interruption by cut-scene to players' immersion and grant players with better immersion. After all, only designs depending on demands and preferences of players by having some knowledge of impacts of cut-scene on players' immersion can be accepted by players.

A Digitally Designed All-on-4 Restoration with Screwmentable Concept

  • Park, Koungjin;Han, Jung-Suk;Lee, Jae-Hyun
    • Journal of Korean Dental Science
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    • 제15권1호
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    • pp.84-91
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    • 2022
  • An all-on-4 restoration allows edentulous patients to use a fixed prosthesis with a minimum number of implants. These implant-supported fixed complete dentures have traditionally been fabricated as screw-retained or cement-retained prostheses. However, it is difficult to passively fit the long-span full-arch prosthesis using the screw-retained type restoration, and predictable retrievability is not obtained with the cement-retained type. This case report describes a prosthesis fabricated using a combination of the two retention types. The screwmentable method allows the implant-supported fixed complete denture to achieve a passive fit at the connection with retrievability. In addition, a framework with an optimized size was designed by using digital dental technology.

Using the pendulum column as an isolator by reducing the gravity effect

  • Abdallah Azizi;Majid Barghian
    • Earthquakes and Structures
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    • 제25권4호
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    • pp.297-305
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    • 2023
  • The conventional method of structural seismic design was based on increasing structural capacity, which usually didn't reduce earthquake seismic effects. By changing the philosophy of structure design, technologies such as passive seismic control have been used in structures. So far, a large number of seismic isolation systems have been introduced to dissipate earthquake energy that is applied to a structure. These systems act against earthquakes rather than increasing the strength and capacity of the structure. In the present paper, a suspended column called a "pendulum column" is investigated, and a new idea has been considered to improve the performance of the pendulum column isolator by changing the gravity effect by adding a spring under the isolator system. The behavior of the studied isolator system has been researched. Then the isolator system was investigated under different earthquakes and compared with a common pendulum column isolator. The results show that changing the gravity effect has an effective role in the response of the system by reducing the system stiffness. Equations for the system showed that even in a special state, complete isolation is possible. Finally, the tested model verified the theory.