• Journal of the Ergonomics Society of Korea
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• v.30 no.5
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• pp.605-611
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• 2011

Objective: The aim of this study was to investigate the influence of seat heights for optimizing the ingress/egress performance in the elderly people. Background: Recently elderly users have been increasing in number and the ease of ingress/egress of the vehicle becomes an important issue. Method: Seven elderly subjects participated in this study(age: 71.7${\pm}$3.6yr, height: 167.7${\pm}$5.4cm, weight: 68.1${\pm}$11.5kg). Each subject performed the sitting and rising task from comfortable seated position on the chair under the following conditions: (1) with a lumbar support and (2) without a lumbar support. We measured EMG activities of seven muscles(tibialis anterior, soleus, gastrocnemius, vastus lateralis, rectus femoris, biceps femoris and erector supinae) and ranges of motion in lower limb during sitting and standing from three different heights (400mm, 500mm and 600mm from ground) of slide-up seat. Results: Muscle activities and angular movements of hip and knee joints during standing-up and sitting-down with a high seat height(600mm) were reduced mean 30.4% in extensor muscles, 57.11% in flexor muscle, 18.74% in erector muscle and 31.0% in joints compared with a low seat height(400mm). Conclusion: Muscle activities and joint movements in hip and knee were reduced when rising/sitting from a high seat height(600mm) compared with a low seat height(400mm). Application: This study can be used to design vehicle that are easy to get in and out of by older peoples with or without impairments.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.6
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• pp.861-866
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• 2011

This paper described the hybrid power generation using ocean wave that consists of linear power generation system and vibrational power generation system. The linear power generation system is made up of the winding coil, the permanent magnet and it is performed stable generation regardless of the wave frequency using directly the ocean wave velocity. And the vibration power generation system consists of the winding coil, the permanent magnet and spring. When the vibration system natural frequency in the vibrational power generation system is tuned to the ocean wave frequency, the relative velocity of between the winding coil and the permanent magnet is faster than the velocity of ocean wave up and down motion, then we can obtain more the electric power. Therefore, in this paper, the proposed hybrid power generation using ocean wave have merits that obtaining the more electric energy in resonance frequency and carrying out stable generation even over the range of resonance frequency.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.10 no.1
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• pp.47-57
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• 2016

In this paper, we measured human body signals in order to verify a active harness system that we developed for gait and balance training. The experimental procedure was validated by tests with 20 healthy male subjects. They conducted motions of Activities of Daily Living(ADL)(Normal Walking, Stand-to-Sit, Sit-to-Stand, Stair Walking Up, and Stair Walking Down) according to body weight support rates (0%, 30%, 50% of subjects' body weight). The effectiveness of the active harness system is verified by using the results of foot pressure distribution. In normal walking, the decrease of fore-foot pressure, lateral soleus muscle and biceps femoris muscle were remarkable. The result of stand-to-sit results motion indicated that the rear-foot pressure and tibialis anterior muscle activities exceptionally decreased according to body weight support. The stair walking down show the marked drop of fore-foot pressure and rectus femoris muscle activities. The sit-to-stand and stair walking up activities were inadequate about the effect of body weight support because the velocity of body weight support system was slower than male's activity.

• Journal of Korean Public Health Nursing
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• v.13 no.2
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• pp.101-114
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• 1999

This study was designed to investigate the effects of an aquatic exercise program on the shoulder joint function. physical symptom. quality of life and stress among the patients who received modified radical mastectomy between 6 to 12 months prior to their visits. The subjects were 31 women aged between 40 and 60 who visited the out-patient department at Kang Nam St. Mary's Hospital for follow-up care. and were not under the treatment of intravenous cancer chemotherapy or radiation therapy. and had no complications. Twelve of them were assigned to the control group. while nineteen subjects to the experimental group. The aquatic exercise program was developed by the author with the assistance of exercise specialists. The program includes warming uP. aerobic and cooling down exercises in water. The aquatic exercise program for the experimental group was carried out 3 times a week with 60 minutes in each time for 8 weeks from September 20th to November 15th. 1995 in a regular swimming pool in Seoul. Changes in the range of motion of the shoulder joint. muscle strength. physical symptom. quality of life. and stress were examined after the completion of treatment. The data were collected through isokinetic muscle strength evaluation and questionnaire survey before and after the treatment. Paired and unpaired t-test were adopted to analyze the data. The results were as follows ; 1. The increment in the range of motion of the shoulder joint in the experimental group after the exercise was significantly greater than those in the control group. 2. The peak torque of shoulder girdle muscles increased significantly after the exercise in the experimental group only. 3. The physical symptom score decreased significantly after the exercise in the experimental group only. 4. The experimental group revealed significantly higher level of quality of life and lower level of stress after the exercise compared with those before the exercise. whereas the control group showed no significant changes in those levels. These findings may indicate that the aquatic exercise program is effective in increasing the range of motion of the shoulder joint and muscle strength and quality of life. and also effective in decreasing physical symptoms. and the level of stress in postmastectomy patients. Accordingly. the acquatic exercise program' can be adopted as an effective nursing intervention for postmastectomy rehabilitation.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.7 no.2
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• pp.55-62
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• 2013

The exoskeleton robot to assist walking of hemiplegia patients or disabled persons has been studied in this paper. The exoskeleton robot with degrees of freedom of 2 axis has been developed and tested for joint motion. The obtained EMG signal from normal person was analyzed and the control signal was extracted from it for convenient and automotive performance of assistance robot to help hemiplegia patient walks as normal person does. the purpose of using FES(Functional Electrical Stimulation) for hemiplegia patient's walk is to restore damaged body function by this, but this could give fatal electrical shock to patients by wrong use or cause quick fatigue in muscle by continuous stimulation. The convenient movement of hemiplegia patients with minimum muscle fatigue was looked possibly by operation of assistance robot exoskeleton using control signal. and the walking assistance exoskeleton robot seemed works more efficiently than using FES stimulator. The experiment in this study was performed based on usual motion in our life like walking, standing-up, sitting-down, and particularly feedback control system using Piezo sensor along with button switch was applied for smooth swing motion in walking. The experiment also shows that hemiplegia patients can move conveniently by using electromyogram signal of healthy leg for the operation signal of assistance robot system attached at damaged symmetrical leg.

• Journal of Korean Medical classics
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• v.7
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• pp.198-231
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• 1994

Up to now, after I had examined the relation between the origin of Fung(風) and Gi(氣) and the mean of Fung in medical science, I obtained the conclusion being as follows. The first, Fung(風) means a flux of Gi(氣) and Gi shows the process by virtue of the form of Fung, namely, Fung means motion of Gi. In other words, it is flow of power. Accordingly, the process of all power can give a name Fung. The second, Samul(事物) ceaselessly interchange with the external world to sustain the existence and life of themselves. And they make a adequate confrontation against the pressure of the outside. This the motive power of life action(生命活動) is Gi and shows its the process on the strength of Fung. The third, Samul(事物) incessantly releases power which it has to the outside. Power released to the outside forms the territory of the established power in the environment of them and keep up their substance(實體) in the space time(時空). It can be name Fung because the field(場) of this power incessantly flows. The fourth, man operates life on the ground of the creation of his own vigor(生氣) for himself as the life body(生命體) of the independence and self-support. The occurence of this vigor and the adjustment process(調節作用) is supervised by Gan(肝). That is to say, Gan plays a role to regulate and manage the process of Fung or the action of vigor with Fung-Zang(風臟). The fifth, because the Gi-Gi adjustment process(氣機調節作用) of Gan is the same as the process of Fung, Fung that operates the cause of a disease is attributed to the disharmony of the process of the human body Gi-Gi. Therefore, the generating pathological change is attributed to the extraordinary of the function by the incongruity of Gi-Gi(氣機) or the disorder of the direct motion of Gi-Hyul(氣血). Because the incongruity of this Gi-Gi of the human body gives rise to the abnormal of Zung-Gi(正氣) in the human body properly cannot cope with the invasion of 'Oi-Sa(外邪). Furthermore, Fung serves as the mediation body of the invasion of other Sa-Gi(邪氣) because of its dynamics, By virtue of this reason, Fung is named the head of all disease. And because the incongruity of the Gi-Gi has each other form according to Zang-Bu(臟腑), Kyung-Lak(經絡), and a region, the symptoms of a disease appear differently in line with them as well. The sixth, Fung-byung(風病) is approximately separated Zung-Fung(中風) and Fung-byung(猍義의 風病). Zung-fung and Fung-byung is to be attributed to the major invasion of each Jung-gi and Fung-sa(正氣와 風邪). But these two kinds stir up the problem to the direct motion of Gi-hyul(氣血) and the harmony of Gi-Gi in the human body. When one cures it, therefore, Zung-fung has to rectify Gi-Gi and the circulation of Gi-hyul on the basis of the supplement of Jung-gi(正氣) and Fung-byung must make the harmony of Gi-Gi with the Gu-fung(驅風). -Go-gi(調氣), Sun-Gi(順氣). Hang-Gi(行氣) - All existing living things as well as man maintain life on the ground of the pertinent harmony between the soul(精神) and the body(肉體). As soon as the harmony falls down, simultaneously life disappears as well. And Fung which means the outside process between Gi(氣) and Gi(氣) makes the action of their life cooperative and unified, Accordingy, the understanding of Fung, first, has to start wi th the whole thought that not only all Samul(事物) but also the soul and the body are one.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.5 no.1
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• pp.11-21
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• 1994

The vocal pitch is controlled by the tension, mass, and length of the vocal fold. It is well known that cricothyroid approximation raises the vocal pitch by simulating the contraction of the cricothyroid muscle, and there were so many reports that have noted a relationship between cricothyroid distance and pitch control, but there does not seem to be any single generally accepted theory to account for this connection. It is generally known that the strap muscles are active during low and falling Fo, and the suprahyoid muscles are active during high and raising Fo. These findings can be related to a general picture of the motion of the larynx during changes in Fo, the cricothyroid joint would tend to lengthen the vocal folds, as the larynx moves up and forward, and relax them as it moves back and down. In this study, we suggest that the relationship between anterior cricothyroid distance and fundamental frequency of the larynx was so complex according to the level of larynx and vertebral curvature. The higher the level of larynx, the wider the cricothyoid distance, but there is more greater fundamental frequency even though more wide cricothyroid distance. This phono-menon seems to be due to the multifactors, especially the vertical tension of the conus elasticus or the change of cricothyroid articulation. It is generally known that the crocothyoid and vocal is muscles are very closely related to pitch elevation, but sternohyoid muscle seems to be more closely related to pitch lowering. By this electromyographic studies, the sternohyoid muscle have dual activity to pitch control, increased activity during the low fundamental frequency and falling pitch, but also increased activity during the higher fundamental frequency and raising pitch at least in this study.

• Journal of the Korean Society of Clothing and Textiles
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• v.39 no.1
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• pp.63-76
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• 2015

This study conducted a survey to gauge the buying and wearing propensities of wearers of leg guards made for baseball catchers, as well as product characteristics of preferred leg guards. Data from the survey were analyzed to obtain basic data for the development of an advanced leg guard design. Degree of compression, horizontal distance, cross section view and outline 3D sketch were also analyzed from the 3D data of leg guards; in addition, mobility and kinematic analysis were conducted through a wearing test. The survey indicated that imported products dominate the current retail market because they are appreciated by customers in terms of fit, price, brand, and protection. Representative complaints of products were discomfort, pressure, and the heavy-weight of the leg guards in general attributed to overall structure and 3D shape. When the pressure was lower on the front area of knee, it feels better to wear and the average knee angular velocity during the up and down motion increased, which suggests a better design from a kinematic point of view. The knee is the primary part of the body responsible for any movement of the lower limbs; consequently, the degree of compression and support stability of the leg guards near the knee area are important factors to evaluate the performance of leg guards. The results of our study indicate significant opportunities for improvement in product design and the development of baseball leg guards along with an ergonomic design that considers the mobility of the knee, skin deformations is necessary to improve performance. The process followed in this study will be applicable to studies on other personal protective equipment for sports.

• Journal of Korean Academy of Nursing
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• v.30 no.5
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• pp.1318-1332
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• 2000

The purpose of this study was to determine the effect of walk training on leg strength, flexibility, postural stability, balance and gait in home bound elderly women. Eighteen elderly women of the experimental group aged between 70 and 90 years image who have normal vision, hearing and Romberg test. They participated in the 12 week walk training. The subjects of the experimental group practiced walk training 3 times a week for during 12 weeks. During the 40 minute workout, the subjects practiced 5 minutes of warming-up exercises, 30 minutes of conditioning exercises and 10 minutes of a cool-down exercise. The intensity for the conditioning phase was determined by subject' heart rates, which ranged from 60% to 70% of age-adjusted maximum heart rates. The body composition, leg strength, flexibility, postural stability, balance and gait were measured prior to and after the experimental treatment. The body fat, lean body mass, leg strength (ankle dorsiflexor, plantarflexor, inversor and eversir, knee flexor, extensior), flexibility (range of motion of ankle dorsiflexion, plantarflexion, inversion and eversion), and postural stability of the experimental group were significantly greater than those of the control group. Duration of standing on the right foot and that of standing on the left foot of the experimental group was greater than that of the control group. Total balance scores of the experimental group were significantly higher than those of the control group. Among 13 items for balance, the scores of experimental group in balance with eyes closes, turning balance, sternal nudge, neck turning, one leg standing balance and back extension were higher than those of the control group. Total scores of gait of the experimental group were significantly higher than those of the control group following the walking training. Scores of experimental group in step height, step length and walk stance while walking among 9 items for gait were significantly higher than those of the control group. The results suggest that walk training can improve physical fitness for prevention in home bound elderly women.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.394-394
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• 2013

The spin-orbit interaction has received great attention in the field of spintronics, because of its property and applicability. For instance, the spin-orbit interaction induces spin precession which is the key element of spin transistor proposed by Datta and Das, since frequency of precession can be controlled by electric field. The spin-orbit interaction is classified according to its origin, Dresselhaus and Rashba spin-orbit interaction. In particular, the Rashba spin-orbit interaction is induced by inversion asymmetry of quantum well structure and the slope of conduction band represents the strength of Rashba spin-orbit interaction. The strength of spin-orbit interaction is experimentally obtained from the Shubnikov de Hass (SdH) oscillation. The SdH oscillation is resistance change of channel for perpendicular magnetic field as a result of Zeeman spin splitting of Landau level, quantization of cyclotron motion by applied magnetic field. The frequency of oscillation is different for spin up and down due to the Rashba spin-orbit interaction. Consequently, the SdH oscillation shows the beat patterns. In many research studies, the spin-orbit interaction was treated as a tool for electrical manipulation of spin. On the other hands, it can be considered that the Rashba field, effective magnetic field induced by Rashba effect, may interact with external magnetic field. In order to investigate this issue, we utilized InAs quantum well layer, sandwiched by InGaAs/InAlAs as cladding layer. Then, the SdH oscillation was observed with tilted magnetic field in y-z plane. The y-component (longitudinal term) of applied magnetic field will interact with the Rashba field and the z-component (perpendicular term) will induce the Zeeman effect. As a result, the strength of spin-orbit interaction was increased (decreased), when applied magnetic field is parallel (anti-parallel) to the Rashba field. We found a possibility to control the spin precession with magnetic field.