• Title/Summary/Keyword: eccentric

Search Result 904, Processing Time 0.026 seconds

Effect of Non-elastic Taping on Ankle Dorsiflexion and Activity of the Triceps Surae Muscles While Vertical Jumping (수직점프 시 비탄력 테이핑이 발목 발등굽힘과 하퇴삼두근의 근활성도에 미치는 영향)

  • Kim, Geun-Su;Weon, Jong-Hyuck;Jung, Do-Young
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.11 no.4
    • /
    • pp.11-17
    • /
    • 2016
  • PURPOSE: There are several standard interventions for managing Achilles tendinitis, including eccentric exercise and calf muscle stretches, orthoses, electrotherapy, and taping. However, no study has determined the effect of non-elastic taping on deloading the Achilles tendon while vertical jumping. Therefore, this study determined the effect of non-elastic taping on ankle dorsiflexion and the triceps surae muscle activity while vertical jumping in healthy subjects. METHODS: The study recruited 17 participants. A motion analysis system was used to measure the angle of ankle dorsiflexion and wireless surface electromyography was used to measure the soleus and gastrocnemius activities while vertical jumping. Non-elastic taping was applied on randomized leg side. All subjects performed maximal effort vertical jumps without and with non-elastic taping, with three trials for each condition. The mean peak dorsiflexion and muscle activities during the three trials were calculated and paired t-tests were used to compare the mean values without and with non-elastic taping. Significance was defined as (p<.05). RESULTS: The maximum angle of ankle dorsiflexion and activity of the gastrocnemius muscle decreased significantly when non-elastic tape was applied (p<.05), while there was no significant difference in the soleus activity between no-taping and taping (p>.05). CONCLUSION: We introduce non-elastic taping as a method to decrease maximum ankle dorsiflexion and gastrocnemius activity while vertical jumping.

Design of Wedge in the Electro-Mechanical Brakes for Commercial Vehicles to Boost Braking Friction Forces (브레이크 마찰력 증가를 위한 상용차용 전기-기계식 브레이크의 쐐기 설계)

  • Lee, Sang Min;Park, Jeonghun;Nam, Kanghyun;Yoo, Chang-Hee;Park, Sang-Shin
    • Tribology and Lubricants
    • /
    • v.34 no.2
    • /
    • pp.55-59
    • /
    • 2018
  • This paper proposes a new type of electro-mechanical wedge brake for commercial vehicles. The brake operates on a novel mechanism for self-boosting braking friction forces using eccentric shafts, and involves wedges that are inserted between the rampbridge and traverse; this self-boosting mechanism is explained herein. A dynamic analysis using ADAMS was conducted, and the findings are reported. The constraint and contact conditions are explained to verify the precision of the dynamic analysis. The dynamic analysis shows that in the proposed mechanism, the self-boosting effect occurs as desired. However, it is also noted that the system has a limitation in terms of the production of unlimited braking forces that can jam the roller inside the wedges. After demonstrating the self-boosting effect, dynamic analyses are performed for several values of the wedge angles and friction coefficients between the brake pads and disks. Conventionally, a lower wedge angle has been suggested owing to its provision of a larger clamping force for given friction coefficients. However, it is noted that lower wedge angles can lead to a higher probability of occurrence of undesirable high braking forces, which can jam the roller into the wedge; thus, a larger wedge angle is preferable for avoiding the undesirable jamming phenomena. These analysis results are presented and discussed herein.

Echocardiographic Diagnosis of Mitral Valve Dysplasia Concurrent with Mitral Stenosis and Tricuspid Valve Dysplasia in a Dog (개에서 승모판 이형성증과 병발한 승모판 협착증 및 삼첨판 이형성증의 심초음파적 특징 1례)

  • Choi, Soo-Young;Lee, Jung-Woo;Lee, Young-Won;Choi, Ho-Jung
    • Journal of Veterinary Clinics
    • /
    • v.32 no.1
    • /
    • pp.101-104
    • /
    • 2015
  • A 4-years-old, intact male Golden retriever dog was presented with abdominal distension and dyspnea. Physical examination revealed arrhythmia and cardiac murmur. Generalized cardiomegaly, pleural effusion and ascites were shown on thoracic and abdominal radiographs. Two-dimensional echocardiography revealed abnormal mitral and tricuspid valve motion, mitral and tricuspid regurgitation, left ventricular eccentric hypertrophy and left atrial dilation. Color-flow Doppler imaging revealed turbulent flow extending into the left ventricle during diastole from the mitral valve orifice, and into the left atrium during systole. Spectral Doppler recordings revealed highly increased early diastolic mitral valve inflow and prolonged pressure half-time of mitral inflow. Based on the echocardiographic examination, the diagnosis was made as the mitral valve dysplasia concurrent with mitral valve stenosis and tricuspid valve dysplasia.

AN INTEGRATED EMG STUDY OF THE RELATIONSHIP OF STERNOCLEIDOMASTOID AND MASSETER MUSCLES DURING OCCLUSAL FUNCTION (교합기능시 흉쇄유돌근과 교근의 관계에 대한 근전도학적 연구)

  • Kim, Kyo-Chul;Choi, Boo-Byung
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.27 no.2
    • /
    • pp.37-52
    • /
    • 1989
  • The purpose of this study was to investigate the relationship between sternocleidomastoid (SCM) and masseter muscles during occlusal functions by means of EMG recordings of examined muscles. For the study, eighteen normal subjects were selected and the Bio-electric Processor EM2 (Myo-tronics Research, Inc., U.S.A.) with the surface electrodes was used to record the EMG activity from the right and left middle of masseter and insertion of SCM of each subject during right and left gum-chewing and isometric contraction by changing the biting force at right eccentric position of jaw. The amount of biting force ranged from 5 to 70kg during isometric contraction were measured by use of Jaw Force Meter. (Nihon Koden Kogyo, Japan.) The results were as follows: 1. The activity onset of SCM and masseter on the same side was almost at the same time, and integrated EMG values of two muscles on the chewing side were higher than the same named muscles on the non-chewing side during gum-chewing. (p<0.01) 2. The regression correlation was not present between both masseters (p>0.05), but between both SCM muscles or muscles of two kinds on the chewing or non-chewing side. ($p{\leqq}0.05$) 3. The integrated EMG value of SCM on chewing or non-chewing side were about 10 percent of that of ipsilateral masseter. 4. Mean voltage of each examined muscles were almost proportional to biting force during isometric contraction and the slope of voltage/biting force line was steepest at the ipsilateral masseter, followed by contalateral masseter, ipsi- and contra-lateral SCM muscles. 5. Mean voltage of ipsilateral masseter was highest during isometric contraction, followed by ipsilateral masseter, contra- and ipsi-lateral SCM muscles.

  • PDF

A comparison of three performance-based seismic design methods for plane steel braced frames

  • Kalapodis, Nicos A.;Papagiannopoulos, George A.;Beskos, Dimitri E.
    • Earthquakes and Structures
    • /
    • v.18 no.1
    • /
    • pp.27-44
    • /
    • 2020
  • This work presents a comparison of three performance-based seismic design methods (PBSD) as applied to plane steel frames having eccentric braces (EBFs) and buckling restrained braces (BRBFs). The first method uses equivalent modal damping ratios (ξk), referring to an equivalent multi-degree-of-freedom (MDOF) linear system, which retains the mass, the elastic stiffness and responds in the same way as the original non-linear MDOF system. The second method employs modal strength reduction factors (${\bar{q}}_k$) resulting from the corresponding modal damping ratios. Contrary to the behavior factors of code based design methods, both ξk and ${\bar{q}}_k$ account for the first few modes of significance and incorporate target deformation metrics like inter-storey drift ratio (IDR) and local ductility as well as structural characteristics like structural natural period, and soil types. Explicit empirical expressions of ξk and ${\bar{q}}_k$, recently presented by the present authors elsewhere, are also provided here for reasons of completeness and easy reference. The third method, developed here by the authors, is based on a hybrid force/displacement (HFD) seismic design scheme, since it combines the force-base design (FBD) method with the displacement-based design (DBD) method. According to this method, seismic design is accomplished by using a behavior factor (qh), empirically expressed in terms of the global ductility of the frame, which takes into account both non-structural and structural deformation metrics. These expressions for qh are obtained through extensive parametric studies involving non-linear dynamic analysis (NLDA) of 98 frames, subjected to 100 far-fault ground motions that correspond to four soil types of Eurocode 8. Furthermore, these factors can be used in conjunction with an elastic acceleration design spectrum for seismic design purposes. Finally, a comparison among the above three seismic design methods and the Eurocode 8 method is conducted with the aid of non-linear dynamic analyses via representative numerical examples, involving plane steel EBFs and BRBFs.

A Study on the Amount of Mandibular Rotation and Pattern of Condylar Path (하악운동 회전량과 과로의 형태에 관한 연구)

  • Kyung-Soo Han;You-Me Lee
    • Journal of Oral Medicine and Pain
    • /
    • v.21 no.2
    • /
    • pp.369-382
    • /
    • 1996
  • The author performed this study to investige the relationship between condylar movements recorded with Pantronicⓡ and mandibular rotational torque movements with BioEGNⓡ. For this study 56 patients with Temporomandibular disorders(TMD) and 30 dental students without any masticatory signs and symptoms were selected as patients group and control group, respectively. The items recorded with Pantronicⓡ(Denar Corp., USA) were immediate side-shift, progressive side-shift, angle of orbiting path, protrusive path and PRI. BioEGNⓡ(Bioelectric gnathography, Bioresearch Inc., USA) were used to measure the amounts of mandibular rotational torque movements in frontal and horizontal plane, and the distance of mandibular translation at incisal area. Amount of mandibular rotational torque movement depicted between the condyles was automatically analysed by angle and difference in frontal and horizontal plane. The obtained data were processed with SAS program and the conclusion of this study were as follows : 1. Mean values of items between patients group and control group in Pantronic measurements were not significantly different except in left protrusive path and in Pantronic Reproducibility Index(PRI). There were no significant difference of condylar paths by preferred chewing side and affected side between the two groups. 2. The amount of mandibular rotational torque movements were differed in frontal angle and difference on protrusion, and in frontal and in horizontal difference on left excursion between the two groups. But the amounts of translatory movements were actually same on all eccentric movements. 3. The amount of mandibular rotational torque movements with splint mere almost not changed from those without splint, with the exception of in horizontal measurements on protrusion. 4. The correlations of items between in Pantronic measurements and in BioEGN measurements wert not consistently, significant, however, generally the ISS related significantly with horizontal torque movement positively, and with frontal torque movement negatively on the contrary, the PSS showed positive correlation with frontal torque movement, and negative correlation with horizontal torque movement.

  • PDF

Efficacy of Microcurrent Electrical Neuromuscular Stimulation with Different Types of Stimulating Electrodes (미세전류치료기 전극 종류에 따른 효능 비교)

  • Choi, Hyo-Jeong;Kim, Sung-Soo
    • Journal of Korean Medicine Rehabilitation
    • /
    • v.23 no.3
    • /
    • pp.107-116
    • /
    • 2013
  • Objectives The purpose of this study was to evaluate the most effective stimulating electrode in Microcurrent electrical neuromuscular stimulation (MENS) for pain relief, and to apply to the treatment of Delayed onset muscle soreness (DOMS). Methods We included 45 participants who met the inclusion criteria. DOMS of both Triceps Surae Muscles were experimentally induced through eccentric contractions. 24-hours after induction of DOMS, who scored more than 40 mm in visual analogue scale (VAS) were randomly assigned into three groups (n=44). In 15 of them, needle electrodes were inserted into BL57, BL56. In 15 of them, surface electrodes were applied on the same points and the others were treated with manual acupuncture. The effects of pain relief were assessed by visual analogue scale (VAS), mechanical pain threshold (MPT), surface electromyography (SEMG). Results In VAS, group comparison had no significant difference after all treatments had done. The difference in VAS between the time before the treatment was started (Day 2) and after all treatments were completed was greater in Acupuncture group than that of needle-electrode group. In MPT, there was no significant difference among groups. Electrical contraction decreased significantly at 2nd before-after treatment comparison in needle-electrode MENS group. But fatigue scores were not significantly different between groups. Conclusions The results suggest that the types of electrodes has no significant effect on microcurrent therapy in DOMS.

Difference of The Cardiac Structure and Function Depending on Obesity Level of Healthy Adults

  • Shin, Kyung-A;Hong, Seung-Bok
    • Biomedical Science Letters
    • /
    • v.17 no.2
    • /
    • pp.141-149
    • /
    • 2011
  • The purpose of this study was to find out any difference and correlation between the cardiac structure and its function according to the level of obesity as evaluated by waist measurement and BMI (body mass index) in healthy adults. For research subjects, the study selected a final 519 subjects excluding 198 subjects aged 55 or over out of 717 subjects who received echocardiography through a medical checkup at J General Hospital. For the criteria for obesity, men were defined as being obese in case their waist measurement was over 90 cm, whereas women were defined as being obese in case their waist measurement was over 80 cm. Also, regarding the BMI criteria, in case a person's BMI was 30 kg/$m^2$, the subject was classified as belonging to an obese group, and in case a person's BMI was between 25 kg/$m^2$ and 30 kg/$m^2$, the subject was classified as belonging to an overweight group. Concerning the evaluation of cardiac structure and function, they were evaluated using two-dimensional, M-mode, doppler echocardiography. According to the stage of obesity in accordance with waist measurement and BMI, the cardiac structure showed both eccentric and centripetal changes, and the cardiac function was also discovered to show differences according to the stage of obesity. In addition, also in the overweight group, which is a prior stage to obesity, out of the criteria for obesity classification according to BMI, there were differences in the cardiac structure and function. Also, both the waist measurement and BMI were found to have a correlation with cardiac structure and diastolic function. Consequently, cardiac structure and function are correlated with BMI and waist measurement, which are anthropometrical variables, and obesity is assumed to induce not only structural change but also functional change of the heart.

Application of Aggregate Recycled in-situ for Anti-frost Layer and Lean Concrete Base Course (저노현장파쇄 순환골재의 동상방지층 및 빈배합콘크리트기층 정용성평가)

  • Kim Jin-cheol;Shim Jae-won;Cho Kyou-sung
    • Resources Recycling
    • /
    • v.14 no.4 s.66
    • /
    • pp.10-16
    • /
    • 2005
  • In order to recycle the waste concrete from which the reproductive aggregate should be produced in-situ, the applicability of crushers and recycled aggregates, and the compliance with the specification have been evaluated comprehensively. As a result of them, the properties of recycled aggregate particles were inferior to the natural one because of the adherent mortars on the recycled one, and the mobile impact crusher and the eccentric-mounted cone and jaw were superior to the others for the graded aggregates. In the case of anti-frost layer, the recycled one was easily controlled since the dry densities, contrary to natural one, were not largely changed with the moisture contents. It was found that the lean concrete base course is not influenced by absorption as cement dust grows larger, and the 7-day compressive strengths of lean concrete were higher than 10 MPa regardless of the crushing type.

The Response Modification Factor of Inverted V-type Braced Steel Frames (역V형 가새골조의 반응수정계수)

  • Ahn, Hyung Joon;Jin, Song Mei
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.17 no.1
    • /
    • pp.1-9
    • /
    • 2013
  • In this study of Eccentric Braced Frames have identified the following target eccentricity on the length of the inelastic behavior of the reaction by calculating the correction factor by comparing it to the value suggested by the earthquake provided material for the rational design aims to There are. As a variable-length V-braced frame analysis model stations were set up. Eccentricity faults in the model according to the length stiffness ratio, the maximum amount of energy dissipation were analyzed base shear and multi-layered model of the reaction from the eccentricity correction factor calculated on the length of the building standards proposed by KBC 2009 in response eccentricity correction factor calculated from The length varies. does not have the same response modification factor was confirmed.