• Proceedings of the ESK Conference
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• 1994.04a
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• pp.49-51
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• 1994

The aims of this study were first to determine the influence of vibration displacement amplitude $(200{\mu}m, 300{\mu}m peak-to-peak)$ at selected frequencies (40-200Hz) on a commonly observed but often undesired motor response elicited bylocal vibratory stimulation, the Tonic Vibration Reflex (TVR). Second, to determine the degree of synchronization of motor unit (MU) activity with vibratory stimuli. Vibration was applied to the distal tendons of the hand flexor muscles. Changes in root- mean-square electromyographic (EMG) activity of the finger and wrist flexor muscles were analyzed both as a function of their initial contraction level (0%, 10%, 20% of the maximal voluntarycontraction: MVC) and as a function of the vibration parameters. The results indicate that the TVR increased with the initial muscle contraction up to 10% MVC: The TVR increased with vibration frequency up to 100-150 Hz and decreases beyond; A significant increase of the TVR with vibration displacement amplitude was observed only for the wrist flexor muscle; MU synchronization at vibration frequency (VF) was found more often in the low frequency range $(f{\leq}100 Hz)$ and tended todecrease beyond; In the high frequency range $(f{\geq}120 Hz)$, MU activity at subharmonic frequency was predominant; The "cut-off" frequency of the synchronization with VF was neither affected by the vibration displacement amplitude nor initial muscle contraction level. The surface EMG turned out to be a useful means to analyze MU synchronization since it is noninvasive, and it can be easily used for analysis of different muscle contraction levels, while single MU technique might have some difficulties at high muscle contraction levels. Furthermore, these results indicate that high frequencyvibration (f>150 Hz) tends to induce less muscle/tendon stress and MU synchronization. Such remarks are of importance for the design of hand-held vibrating tools.ing tools.

• Journal of Korean Medicine Rehabilitation
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• v.18 no.1
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• pp.125-140
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• 2008

Objectives : The purpose of this study was to investigate the effect of Progressive Muscle Relaxation(PMR) on stress and muscle relaxation in healthy people. Methods : Sample group of 14 healthy subjects had been treated by progressive muscle relaxation for 10 days. Control group of 14 healthy subjects were not treated during the same period. Outcomes were assessed by Meridian-Electromyograph(MEMG), Heart Rate Variability(HRV), Stress Reaction Inventory(SRI). Results : The contraction and fatigue of erector spinae muscle by MEMG had decreased significantly in Sample group. There was no significant difference between two groups in the HRV and SRI. Conclusions : Further studies analysing PMR effect on stress and muscle relaxation are needed.

• Journal of Korean Orthopaedic Sports Medicine
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• v.7 no.1
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• pp.8-14
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• 2008

Elbow joint injuries during exercise mostly occur by repeated stress to the joint than direct trauma. A pitcher who uses his arm above his head is most likely to be injured. So learning the right way to exercise and gaining the strength by maturating the body are essential for diminishing the chance of injury. On lateral ulnar tendon injury, which is most commonly injured area on elbow joint, pitchers generally complain of pain in arm movement above head and reduction of velocity, accuracy, and number of pitching. When there is pain on upper arm in harsh using, the stress fracture must be thought and epicondylar physis fracture of medial arm can occur by repeated abduction stress and contraction of flexors on forearm on children with immature skeleton. Osteochondritis dissecans of capitullum occur in young athletes who use there upper limb continuously lifting weights and gym work. And stress of abduction-extension includes damage of soft tissue and bone components, post medial crush syndrome, lateral ulnar ligament injury, extensor-abductor injury, stress of radius- capitullum are in this category.

• Korea-Australia Rheology Journal
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• v.21 no.4
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• pp.225-233
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• 2009

In various attempts to relate the behaviour of highly-elastic liquids in complex flows to their rheometrical behaviour, obvious candidates for study have been the variation of shear viscosity with shear rate, the two normal stress differences $N_1$ and $N_2$, especially $N_1$, and the extensional viscosity $\eta_E$. In this paper, we shall be mainly interested in 'constant-viscosity' Boger fluids, and, accordingly, we shall limit attention to $N_1$ and $\eta_E$. We shall concentrate on two important flows - axisymmetric contraction flow and "splashing" (particularly that which arises when a liquid drop falls onto the tree surface of the same liquid). Modern numerical techniques are employed to provide the theoretical predictions. It is shown that the two obvious manifestations of viscoelastic rheometrical behaviour can sometimes be opposing influences in determining flow characteristics. Specifically, in an axisymmetric contraction flow, high $\eta_E$ can retard the flow, whereas high $N_1$ can have the opposite effect. In the splashing experiment, high $\eta_E$ can certainly reduce the height of the so-called Worthington jet, thus confirming some early suggestions, but, again, other rheometrical influences can also have a role to play and the overall picture may not be as clear as it was once envisaged.

• Steel and Composite Structures
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• v.8 no.1
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• pp.1-18
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• 2008

Observations from experiments and real fire indicate that restrained steel beams have better fire-resistant capability than isolated beams. Due to the effects of restraints, a steel beam in fire condition can undergo very large deflections and the run away damage may be avoided. In addition, axial forces will be induced with temperature increasing and play an important role on the behaviour of the restrained beam. The factors influencing the behavior of a restrained beam subjected to fire include the stiffness of axial and rotational restraints, the load type on the beam and the distribution of temperature in the cross-section of the beam, etc. In this paper, a simplified model is proposed to analyze the performance of restrained steel beams in fire condition. Based on an assumption of the deflection curve of the beam, the axial force, together with the strain and stress distributions in the beam, can be determined. By integrating the stress, the combined moment and force in the cross-section of the beam can be obtained. Then, through substituting the moment and axial force into the equilibrium equation, the behavior of the restrained beam in fire condition can be worked out. Furthermore, for the safety evaluation and repair after a fire, the behaviour of restrained beams during cooling should be understood. For a restrained beam experiencing very high temperatures, the strength of the steel will recover when temperature decreases, but the contraction force, which is produced by thermal contraction, will aggravate the tensile stresses in the beam. In this paper, the behaviour of the restrained beam in cooling phase is analyzed, and the effect of the contraction force is discussed.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.4 no.2
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• pp.1-12
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• 2009

Objectives : The purpose of this study was to investigate the relationship between pain and psychological state in female office workers with neck pain. Methods : Experimental group of 31 healthy subjects complained of neck and arm discomfort related to computer use which lasted more than 3 months in the past year and was present in the past 7 days as well as on the day of test. Outcomes were assessed by meridian-electromyography(MEMG), Neck Disability Index(NDI), Visual Analog Scale(VAS), Beck Depression Inventory(BDI), Stress Reaction Inventory(SRI), Holmes & Rahe Social Readjustment Rating Scale(SRRS). Results : The NDI score and BDI score had a correlationship(r=0.48), and the NDI score and SRI score also had a correlationship(r=0.48), significantly. The NDI score and contraction power of upper trapezius by MEMG had a correlationship significantly, but with the other muscles the NDI score didn't have correlationships. The NDI score and the SRI score were significantly higher in depression group(BDI score ${\circ}{\surd}$14). The contraction power of trapezius by MEMG was significantly lower in depression group. Conclusions : The results suggest that mental stress can be a major risk factor of neck pain in female office workers.

• Korean Journal of Pharmacognosy
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• v.20 no.3
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• pp.188-195
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• 1989

Hyangsayangwee-Tang, a combined preparation of crude drugs, which has been used for stomach and intestinal disorder, was examined for anti-spasmodic, anti-ulcerative and anti-emetive effects. Spontaneous motility of isolated ileum was strongly suppressed and inhibitory effects against contraction of isolated ileum induced by acetylcholine and barium chloride were shown in mice. And, contraction of isolated guinea-pig ileum by histamine was inhibited. In rats fundus preparations, Hyangsayangwee-Tang elicited strong relaxation and had antagonist effects against the spasm induced by acetylcholine and barium chloride. A significant inhibitory effect on the intestinal propulsion of barium sulfate in mice was shown. In pylorus-ligated rats, Hyangsangwee-Tang inhibited gastric secretion and showed a strong anti-peptic activity. Protective effects against gastric ulceration induced by pyloric ligation, water-immersion stress, histamine and aspirin were significantly recognized in mice and rats. Hyangsayangwee-Tang decreased cupric sulfate-induced vomitting in frogs.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.2 no.2
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• pp.141-150
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• 2007

Objectives : The purpose of this study was to investigate the correlation of stress and meridian muscle electrography in Korean adult males. Methods : Sixty-nine volunteers suffering from stress participated in this study. Physical examination, stress survey and meridian muscle electrography were performed. Each variable was compared with each other by correlation analysis. Results : Correlation between stress response inventory and fatigue of trapezius muscle right upper portion was statistically significant. In relationship between sub scales of stress response inventory and meridian muscle electrography, fatigue of trapezius muscle right upper portion was statistically significant with tension, depression, and frustration. Contraction power of left sternocleidomastoid muscle was significant with somatization and others were not significant. Conclusions : In Korean adult males, trapezius muscle shows more fatigue under more stress. This suggests that stress influences muscle fatigue. Although meridian muscle electrography is not a typical method for the evaluation of pain nor stress, this is referential method to clinical evaluation of painful shoulder caused stress.

• Journal of Navigation and Port Research
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• v.32 no.2
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• pp.121-126
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• 2008

This paper presents hull stress monitoring system installed in LNGC damaged by a Typhoon Elongation/contraction of removed areas has been assessed in terms of possible residual stress that will take place in replaced blocks when the applied load is removed. The bending moment of a vessel changes actually in terms of loss of longitudinal members and the change of weight distribution in repair procedure. The change of bending moment affects mainly in hull stress of longitudinal members. Hull stress monitoring system was installed on upper deck to prove LNGC stable in the criteria to be less than 40MPa during the period of repair procedure. A temperature measuring system was also installed to exclude the additional stress due to thermal effect from the measured hull stress. As a result, the hull stress was modified with the data measured by the temperature measuring system. This hull stress considering thermal effect was used as a guide stress to check the safety of LNGC during the period of repair procedure.

• Journal of Korean Academy of Nursing
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• v.29 no.1
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• pp.34-47
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• 1999

This study evaluated the Comparison of the Effectiveness of Pelvic Floor Muscle exercise and Biofeedback treatment for Genuine Stress Incontinence I assigned 60 participants to 2 groups : 30 to the pelvic floor muscle exercise group and 30 to the biofeedback group. Treatment protocol lasted for 6 weeks. Peak pressure, and duration time of pelvic muscle contraction were evaluated by a perineometer. Lower urinary symptoms, sexual matter and life style scores were achieved by using Jackson's scale. The treatment efficacy of the pelvic floor muscle exercise is compared with the biofeedback group and the main results of the comparison are as follows : 1. Pelvic muscle contraction 1) The peak pressure in the biofeedback group was significantly increased(P＝0.000). 2. The frequency and quantity of incontinence 1) The frequency of incontinence in the biofeedback group was significantly decreased(P＝0.000). 2) The quantity of incontinence in the biofeedback group was significantly decreased(P＝0.000). 3. The lower urinary symptoms Daily frequency(P＝0.000), nocturia(P＝0.000), urgency(P＝0.000), bladder pain(P＝0.000), unexplained incontinence(P＝0.048), wearing protection(P＝0.022), changing outer clothing(P＝0.005), hesitancy(P＝0.008), intermittent stream(P＝0.000), abnormal strength of stream(P＝0.004), retention(P＝0.000), incomplete emptying(P＝0.000), and inability to stop mid stream(P＝0.006) of the lower urinary symptoms in the biofeedbatk group were significantly decreased. 4. The sexual matters The dry vagina (P＝0.004) and pain during sexual Intercourse (P＝0.002) in the biofeedback group was significantly decreased. 5. The life style The fluid intake restriction(P＝0.007), affected daily task(P＝0.003), avoidance of places & situation(P＝0.003), interference in Physical activity (P＝0.002), interference in relationship with other people(P＝0.01), and feeling about the rest of life with urinary symptom(P＝0.000) in the biofeedback group were significantly decreased. In conclusion, the biofeedback treatment was more effective than the pelvic floor muscle exercise in genuine stress incontinence.