• Title/Summary/Keyword: Tilting unit

Search Result 58, Processing Time 0.025 seconds

Can Abdominal Drawing-In Maneuver Using a Pressure Biofeedback Unit Change Muscle Recruitment Pattern During Prone Hip Extension?

  • Oh, Jae-Seop;Weon, Jong-Hyuck;Cynn, Heon-Seock;Kwon, Oh-Yun
    • Physical Therapy Korea
    • /
    • v.13 no.4
    • /
    • pp.56-63
    • /
    • 2006
  • This study examined the effects of the abdominal drawing-in (ADI) maneuver using a pressure biofeedback on muscle recruitment pattern of erector spinae and hip extensors and anterior pelvic tilt during hip extension in the prone position. Fourteen able-bodied volunteers, who had no medical history of lower extremity or lumbar spine disease, were recruited for this study. The muscle onset time of erector spinae, gluteus maximus, and medial hamstring and angle of anterior pelvic tilt during hip extension in prone position were measured in two conditions: ADI maneuver condition and non-ADI maneuver condition. Muscle onset time was measured using a surface electromyography (EMG). Kinematic data for angle of anterior pelvic tilt were measured using a motion analysis system. The muscle onset time and angle of anterior pelvic tilt were compared using a paired t-test. The study showed that in ADI maneuver during hip extension in prone position, the muscle onset time for the erector spinae was delayed significantly by a mean of 43.20 ms (SD 43.12), and the onset time for the gluteus maximus preceded significantly by a mean of -4.83 ms (SD 14.10) compared to non-ADI maneuver condition (p<.05). The angle of anterior pelvic tilt was significantly lower in the ADI maneuver condition by a mean of 7.03 degrees (SD 2.59) compared to non-ADI maneuver condition (15.01 degrees) (p<.05). The findings of this study indicated that prone hip extension with the ADI maneuver was an effective method to recruit the gluteus maximus earlier than erector spinae and to decrease anterior pelvic tilting.

  • PDF

Structural Distortions and Electrical Properties of Magnetoelectric Layered Perovskites: $Bi_4Ti_3O_{}12.nBiFeO_3$(n=1&2)

  • Ko, Taegyung;Bang, Gyusuk;Shin, Jungmuk
    • The Korean Journal of Ceramics
    • /
    • v.4 no.2
    • /
    • pp.83-89
    • /
    • 1998
  • The structure refinements and the electrical and magnetoelectric measurements were performed for BIT.1BF and BIT.2BT. The tetragonal distortion of the ab plane became lessened with the addition of $4BiFeO_3 into Bi_4Ti_3O_{12}$ significantly. However, the tilting of the outer-oxygen octahedra of the perovskite unit and the elongatin of the $(Bi_2O_2)^{2+}$ layers became more pronounced. For the both phases, the bariations of dielectric properties and electrical conductivities at high temperatures showed that the ferroelectic I-rerroelectric II phase transition existed before reaching the Curie temperature. The electrical conductivity became higher with the increase of $Fe^{3+}$ ions, implying that the electron transfer increased correspondingly. The magnetoelectric effect was observed linear up to ~8 kOe, which was stronger in BIT.1BF than BIT.2BF. This behavior indicates that the distortion of the ab plane may affect the induced polarization as well as magnetic moment.

  • PDF

End Effectors and Flexible Fixtures for Rapidly Holding Freeform-Surface CFRP Workpieces (자유곡면 CFRP 판형 가공물 신속고정용 유연지그 및 엔드 이펙터)

  • Son, Younghoon;Do, Minh Duc;Choi, Hae-Jin
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.34 no.4
    • /
    • pp.243-246
    • /
    • 2017
  • In this study, flexible fixtures and end effectors are conceptually designed for the holding of thin-walled carbon-fiber reinforced-plastic (CFRP) workpieces in machining processes. Firstly, the fixture scenarios and system requirements for the conceptual designs of flexible-fixture and core units are proposed, including the propounding of the workpiece-holding mechanism and the core-unit requirements. A ball-joint pneumatic system is determined as a locking mechanism of the flexible-fixture system for the machining of thin-walled components. Secondly, conceptual designs of the core units are suggested with the driven requirements from the fixture scenarios. A self-tilting mechanism and an end-effector return mechanism are also proposed. Finally, the prototypes of the core units are manufactured, and the workpiece-holding capacity of each prototype is measured.

A Study on the Fabrication of Ni Stamper for 50nm Class of Patterns (50nm급 패턴 니켈 스탬퍼 제작에 관한 연구)

  • Yoo, Yeong-Eun;Oh, Seung-Hun;Lee, Kwan-Hee;Kim, Seon-Gyeong;Youn, Jae-Sung;Choi, Doo-Sun
    • 한국금형공학회:학술대회논문집
    • /
    • 2008.06a
    • /
    • pp.35-38
    • /
    • 2008
  • A pattern master and a Ni stamper for 50nm class of patterns are fabricated through e-beam lithography and Ni electroforming process. A model pattern set is designed, which is based on unit patterns of 50nm, 100nm, 150nm and 200nm in length and 50nm in width. The e-beam process is optimized to fabricate designed patterns with some parameters including dose, accelerating voltage, focal distance and developing time. For Ni electroforming to fabricate Ni stamper, a seed layer, a conducting layer, is deposited first on the pattern master fabricated by an e-beam lithography process. Ni, Ti/Ni and Cr are first tested to find optimal seed layer process. Currently the best result is obtained when adopting Cr deposited to be 100nm thick with continuous tilting motion of the master substrate during the deposition process.

  • PDF

Bearing Pad Temperature Change Depending on the Preload of Vertical Journal Guide Bearing (수직형 저널 베어링에서 preload 변화에 따른 베어링 패드 온도 변화)

  • Kim, Jun-Sung;Kim, Du-Young;Kim, Dong-Kwan;Park, Sang-Ho
    • The KSFM Journal of Fluid Machinery
    • /
    • v.12 no.6
    • /
    • pp.33-40
    • /
    • 2009
  • The temperature of vertical pump bearing metal in the pumped storage power plant has been high enough to shutdown the unit. Attempts such as decreasing the oil supply temperature, increasing the bearing oil gap etc. were performed to resolve the problem, but the issue was not resolved. Finally, the high bearing metal temperature was corrected by adjusting the bearing preload. The preload is formed by the oil wedge between the journal surface and bearing pad surface and the degree of preload is determined by the machined radial clearance, assembled radial clearance, rotor journal diameter etc. This paper focuses on the analysis of the preload depending on the bearing parameters and the result of the modification of the bearing following the analysis. The bearing metal temperature dropped as much as $20^{\circ}C$ which was similar as expected by software calculation. But the shaft vibration could increase when the assembled radial clearance is excessive. So, the adjustment of the bearing preload for the tilting pad type journal bearing should be carefully performed.

Analysis of Media Trends and Social Perceptions on Nursing Law Legislation (간호법 제정에 대한 언론 동향 및 사회적 인식 분석)

  • Lee, Seung-Hee;Joo, Min-Ho
    • Journal of Korean Academy of Nursing
    • /
    • v.53 no.4
    • /
    • pp.439-452
    • /
    • 2023
  • Purpose: This study aimed to derive considerations for the enactment of nursing law by analyzing the trends and social perceptions of nursing law mentioned in major daily newspapers, cafes, and blogs. Methods: Main texts and comments that included nursing law as a keyword were collected from major daily news and online postings from January 2021 to August 2022. The data collected through web crawling were analyzed using a TousFlux program used for big data analysis. Results: During the period of study, the awareness level around nursing law enactment increased. In particular, public concern over nursing law enactment intensified due to the two political parties' policy pledges related to nursing law in January 2022 and the failure to introduce the nursing law to the national assembly judiciary committee in May 2022. Except in December 2021, public perception of nursing law enactment was generally favorable, with public opinion tilting more in favor of than against enactment. Conclusion: Public opinion should be considered when drafting and implementing the nursing law to make it easier for the people to understand what the law constitutes. In addition, it is necessary to pay attention to and continuously promote the relationship between medical care and nursing in the nursing law system of developed nations. Lastly, nursing law enactment can enhance nurses' retention intention and provide a sense of efficacy to medical services.

PHOTOELASTIC STRESS ANALYSIS OF IMPLANT SUPPORTED FIXED PROSTHESES WITH DIFFERENT PLACEMENT CONFIGURATIONS IN MANDIBULAR POSTERIOR REGION (하악 구치부에서 임플랜트 배열방식에 따른 임플랜트지지 고정성 국소의치의 광탄성 응력 분석)

  • Cho Hye-Won;Kim Nan-Young;Kim Yu-Lee
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.43 no.1
    • /
    • pp.120-131
    • /
    • 2005
  • Statement of problem. More than 70% of patients who need the implant supported restoration are parially edentulous. The principles of design for implant supported fixed partial denture in mandibular posterior region are many and varied. Jurisdiction for their use is usually based on clinical evaluation. There are several areas or interest regarding the design of implant supported fixed partial denture in mandibular posterior region. 1) Straight and tripod configuration in implant placement, 2) Two restoration types such as individualized and splinted restorations. Purpose. The purpose of this study was to compare the amount and distribution of stress around the implant fixtures placed in the mandibular posterior region with two different arrangements and to evaluate the effects of splinting using the photoelastic stress analysis. Material & methods. 1) Production of study model: Mandibular partially edentulous model was waxed-up and duplicated with silicone and two models were poured in stone. 2) Fixture installation and photoelastic model construction: Using surveyor(Ney, USh), 3 fixtures(two 4.0 $\times$13 mm, one 5.0$\times$10 mm, Lifecore, USA) were insta)led in straight & tripod configurations. Silicone molds were made and poured in photoelastic resin (PL-2. Measurements group, USA). 3) Prostheses construction: Four 3-unit bridges (Type III gold alloy, Dongmyung co., Korea) were produced with nonhexed and hexed UCLA abutments and fitted with conventional methods. The abutments were tightened with 30 Ncm torque and the static loads were applied at 12 points of the occlusal surface. 4) Photoelastic stress analysis : The polarizer analyzer system with digital camera(S-2 Pro, Fujifilm, Japan) was used to take the photoelastic fringes and analysed using computer analysis program. Results. Solitary hexed UCLA restoration developed different stress patterns between two implant arrangement configurations, but there were no stress transfer to adjacent implants from the loaded implant in both configurations. However splinted restorations showed lesser amount of stresses in the loaded implants and showed stress transfer to adjacent implants in both configurations. Solitary hexed UCLA restoration with tripod configuration developed higher stresses in anterior and middle implants under loading than implants with straight configurations. Splintied 3 unit fixed partial dentures with tripod configuration showed higher stress development in posterior implant under loading but there were no obvious differences between two configurations. Conclusions. The tripod configuration of implant arrangement didn't show any advantages over the straight configuration. Splinting of 3 unit bridges with nonhexed UCLA abutments showed less stress development around the fixtures. Solitary hexed UCLA restoration developed tilting of implant fixture under offset loads.

Effects of Lumbar Stabilization Using Pressure Biofeedback Unit During Hip Abduction in Side-Lying in Patients With Low Back Pain

  • Seo, Young-taek;Chon, Seung-chul
    • Physical Therapy Korea
    • /
    • v.23 no.2
    • /
    • pp.67-74
    • /
    • 2016
  • Background: Lumbar stabilization (LS) improve the thickness of the quadratus lumborum (QL) muscle and muscle activity of the gluteus medius (GM) muscle during hip abduction in a side-lying position in patients with low back pain (LBP). Objects: The purpose of this study was to assess the effects of LS on muscle thickness of QL and muscle activity of GM during hip abduction in side-lying in patients with LBP. Methods: The study included 32 patients with LBP, who were randomly divided into the control group and experimental group, each with 16 patients. All subjects performed $35^{\circ}$ preferred hip abduction (control group) and $35^{\circ}$ hip abduction with LS (experimental group) during side-lying. An ultrasonography and a surface electromyography were used to measure the thickness of the QL muscle, and the muscle activities of the GM muscle respectively. Independent t-test was used to compare the muscle thickness of the QL and the muscle activity of the GM muscle, respectively. Results: Anterio-posterior diameter in the muscle thickness of QL muscle was decreased significantly in hip abduction with LS more than in preferred hip abduction (p<.001), but medio-lateral diameter in the muscle thickness of QL muscle was not significantly different between in preferred hip abduction and in hip abduction with LS (p=.06). The muscle activity of GM was increased significantly in hip abduction with LS more than in preferred hip abduction (p<.001). Conclusion: These findings suggest that hip abduction with LS could be recommended as a hip abduction for LS and a prevention unwanted compensatory pelvic lateral tilting movement.

EMG Signal Analysis of Upper Extremity Motor Function using Balance-handle Device (밸런스 핸들 장치를 이용한 상지 운동 기능의 근전도 신호 분석)

  • Lee, Choong-Keun;Song, Ki-Ho;An, Jae-Yong;Shin, Sung-Wook;Chung, Sung-Taek
    • Journal of rehabilitation welfare engineering & assistive technology
    • /
    • v.10 no.4
    • /
    • pp.295-303
    • /
    • 2016
  • Rehabilitation of upper limb motor function of hemiplegic patient must maintain interest and demand a device for a quantitative evaluation of rehabilitation training. In this paper, we developed the device that is composed of arm cradle, handle, and balance ball for rehabilitation exercise. We have performed experiment for validity as to whether to use the rehabilitation device when tilting the upper extremity training device developed to measure changes in the EMG signal to the main upper limb muscles for 7 healthy volunteers. We have analyzed muscle activation signals on agonist and antagonist as a reference in the muscle contraction and relaxation in the upper limb extension and flexion when the balance-handle device is tilted to front-rear and left-right. The experimental results showed that a tendency of muscle activation of biceps, triceps, and deltoid used in upper limb motor function of hemiplegic patients from extension and flexion evaluation items of Fugl-Meyer Assessment(FMA). These results may be helpful for rehabilitation training for upper limb motor function of hemiplegic patients by utilizing a developed unit.

Chemistry and Rietveld Structure Refinement of Nb-rich Perovskite, $Ca_2NbFe^{3+}O_6$ (네오비움 페롭스카이트($Ca_2NbFe^{3+}O_6$)의 화학조성 및 리트벨트 구조분석 연구)

  • ;Frank C. Hawthorne
    • Journal of the Mineralogical Society of Korea
    • /
    • v.15 no.1
    • /
    • pp.59-68
    • /
    • 2002
  • Chemical analyses and Rietveld structural refinement with powder X-ray diffraction data were done for Nb-rich perovskite, named latrappite ($Ca_2NbFe^{3+}O_6$)from the Oka, Quebec, Canada. Latrappite is shown to be a member of a continuous solid solution of $CaTiO_3-NaNbO_3-Ca_2NbFe^{3+}O_6$ and approximately $(Ca_{1.5}Na_{0.4})\;(Nb_{0.1}Ti_{0.6}Fe_{0.4})O_6$ in composition. The crystal structure of latrappite, determined by Rietveld refinement, is similar to that of perovskite ($CaTiO_3$). It differs in that replacement of Ti by Nb and $Fe^{3+}$ results in greater distortion and tilting of the $TiO_6$ framework octahedra relative to $CaTiO_3$. Revised unit-cell parameters of latrappite are a=5.4474(4), b=5.5264(4), c=7.7519(5) ${\AA},\;V=233.4(3){\AA}^3$ space group Pbnm.