• Korean Journal of Applied Biomechanics
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• v.26 no.1
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• pp.11-20
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• 2016

Objective: This study aimed to compare biomechanical data between elite and beginner cyclists during cycle pedaling by performing a comparative analysis and to provide quantitative data for both pedaling performance enhancement and injury prevention. Methods: The subjects of this study included 5 elite cyclists (age: $18{\pm}0years$, body mass: $64.8{\pm}9.52kg$, height: $173.0{\pm}4.80cm$) and 5 amateur cyclists (age: $20{\pm}0years$, mass: $66.6{\pm}2.36kg$, height: $175.6{\pm}1.95cm$). The subjects pedaled on a stationary bicycle mounted on rollers of the same gear (front: 50 T and rear: 17 T = 2.94) and cadence of 90. The saddle height was adjusted to fit the body of each subject, and all the subjects wore shoes with cleats. In order to obtain kinematic data, 4 cameras (GR-HD1KR, JVC, Japan) were installed and set at 60 frames/sec. An electromyography (EMG) system (Telemyo 2400T, Noraxon, USA) was used to measure muscle activation. Eight sets of data from both the left and right lower extremities were obtained from 4 muscles (vastus medialis oblique [VMO], vastus lateralis oblique [VLO], and semitendinosus [Semitend], and lateral gastrocnemius [Gastro]) bilaterally by using a sampling frequency of 1,500 Hz. Five sets of events ($0^{\circ}$, $90^{\circ}$, $180^{\circ}$, $270^{\circ}$, and $360^{\circ}$) and 4 phases (P1, P2, P3, and P4) were set up for the data analysis. Imaging data were analyzed for kinematic factors by using the Kwon3D XP computer software (Visol, Korea). MyoResearch XP Master Edition (Noraxon) was used for filtering and processing EMG signals. Results: The angular velocity at $360^{\circ}$ from the feet was higher in the amateur cyclists, but accelerations at $90^{\circ}$ and $180^{\circ}$ were higher in the elite cyclists. The amateur cyclists had greater joint angles at $270^{\circ}$ from the ankle and wider knee joint distance at $0^{\circ}$, $180^{\circ}$, and $360^{\circ}$ than the elite cyclists. The EMG measurements showed significant differences between P2 and P4 from both the right VLO and Semitend. Conclusion: This study showed that lower body movements appeared to be different according to the level of cycle pedaling experience. This finding may be used to improve pedaling performance and prevent injuries among cyclists.

• Korean Journal of Applied Biomechanics
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• v.26 no.4
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• pp.343-351
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• 2016

Objective: The purpose of this study was to help improve game performance and provide preliminary data to enhance the efficiency of the kick and stability of the support foot by comparing the kinematic characteristics of the repeated side kick (geodeupyeopchagi) in poomsaeKoryo between expert and non-expert groups. Method: The subjects were divided into 2 groups according to proficiency in Taekwondo, an expert group and a non-expert group (n = 7 in each group), to observe the repeated side-kick technique. Four video cameras were set at a speed of 60 frames/sec and exposure time of 1/500 sec to measure the kinematic factors of the 2 groups. The Kwon3D XPprogramas used to collect and analyze three-dimensional spatial coordinates. Ground reaction force data were obtained through a force plate with a 1.200-Hz frequency. An independent samplesttest was performed, and statistical significance was defined as .05. The SPSS 18.0 software was used to calculate the mean and standard deviation of the kinematic factors and to identify the difference between the experts and non-experts. Results: The angular displacement of the hip joint in both the expert and non-expert groups showed statistical significance on E1 and E4 of the left support foot and E5 of the right foot (p<.05). The angle displacement of the knee joint in both groups showed statistical significance on E4 of the left support foot, and E1 and E2 of the right foot (p<.05). The angular velocity of the lower leg in both groups showed no statistical significance on the left support foot but showed statistical significance on E2 and E6 of the right foot (p<.05). The angular velocity of the foot in both groups showed no statistical significance on the left support foot but showed statistical significance on E2 of the right foot (p<.05). The vertical ground reaction force in both groups showed statistical significance on E2 (p<.05). The center of pressure in all directions in both groups showed statistical significance (p<.5). Conclusion: While performing the repeated side kick (geodeupyeopchagi), the experts maintainedconsistency and stability of the angle of the support leg while the kick foot moved high and fast. On the other hand, the angle of the support foot of non-experts appeared inconsistent, and the kick foot was raised, relying on the support leg, resulting in unstable and inaccurate movement.

• Journal of dental hygiene science
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• v.9 no.5
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• pp.545-550
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• 2009

This study set out to examine the knowledge about and preventive actions against musculoskeletal diseases among dental hygiene students according to the Health Belief Model, suggest a need for programs to promote health and prevent those diseases, and investigate their relations, A survey was taken among 83 sophomores and 114 juniors at the dental hygiene major of a college in Gyeonggi Province. Analyzed by using SAS 8.0 version. The findings are as follows: 1. The sophomores and juniors scored $22.50{\pm}2.37$ and $22.29{\pm}3.01$ points, respectively, on susceptibility of the Health Belief Model with significant differences between the two groups(P < 0.01). Significant differences were also found between the sophomores that scored $18.82{\pm}2.60$ points and the juniors that scored $18.64{\pm}2.77$ points on benefit(P < 0.05). 2. The juniors experienced a higher level of pain than the sophomores with statistical significance observed on the neck, shoulder, lower back, knee, foot, and ankle(P < 0.05). 3. Of the Health Belief Model, severity had significant positive correlations with 'Placing frequently used tools near the dental technician' and 'Trying to avoid repeating the same task and diversify tasks'(P < 0.01). And benefit was positively correlated with 'Trying to reduce the frequency of bending and stretching out during treatment, 'Trying not to lean much with the neck, back, arm, and wrist' and 'Trying to maintain the torso in the neutral position'(P < 0.01). The results suggest that there should be some instructions to help dental hygiene students practice the preventive actions against musculoskeletal diseases and further prevention programs against those diseases.

• Investigative Magnetic Resonance Imaging
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• v.12 no.2
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• pp.131-141
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• 2008

Purpose : To investigate the feasibility and accuracy of Proton Resonance Frequency (PRF) shift based magnetic resonance (MR) temperature mapping utilizing the self-developed center array-sequencing phase unwrapping (PU) method for non-invasive temperature monitoring. Materials and Methods : The computer simulation was done on the PU algorithm for performance evaluation before further application to MR thermometry. The MR experiments were conducted in two approaches namely PU experiment, and temperature mapping experiment based on the PU technique with all the image postprocessing implemented in MATLAB. A 1.5T MR scanner employing a knee coil with $T2^*$ GRE (Gradient Recalled Echo) pulse sequence were used throughout the experiments. Various subjects such as water phantom, orange, and agarose gel phantom were used for the assessment of the self-developed PU algorithm. The MR temperature mapping experiment was initially attempted on the agarose gel phantom only with the application of a custom-made thermoregulating water pump as the heating source. Heat was generated to the phantom via hot water circulation whilst temperature variation was observed with T-type thermocouple. The PU program was implemented on the reconstructed wrapped phase images prior to map the temperature distribution of subjects. As the temperature change is directly proportional to the phase difference map, the absolute temperature could be estimated from the summation of the computed temperature difference with the measured ambient temperature of subjects. Results : The PU technique successfully recovered and removed the phase wrapping artifacts on MR phase images with various subjects by producing a smooth and continuous phase map thus producing a more reliable temperature map. Conclusion : This work presented a rapid, and robust self-developed center array-sequencing PU algorithm feasible for the application of MR temperature mapping according to the PRF phase shift property.

• Women's Health Nursing
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• v.4 no.2
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• pp.217-230
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• 1998

The purpose of this descriptive correlational study was to define the relationship between the experience of Sanhuujori, Korean traditional non-professional postpartal care after delivery and abortion and present health status of chronic arthritis female patient who visited to outpatient clinic of rheumatic internal medicine at a hospital located in Seoul, Korea. A convenience sample of 64 women who orally agreed to be a participant and data were collected form October 1996 to May, 1997 for sis months by way of interview with semistructured questionnaire. The data were analyzed by the SPSS pc program using t-test, ANOVA and Scheffe test as a post hoc and Pearson Correlation Coefficient. The results of the study were as follows ; Mean age of participants was 53.2 years and mean number of children was 3.1. Mean frequency of abortion was 2.1 times per woman. Seventy four percentage of respondents did not have Sanhujori after abortion. The mean period of Sanhujori after delivery was 17.7, 15.2, 13.8 days from the first child to third child and shorter than that of general woman such as 20.0, 19.0, 17.3 days in the previous study. On the subjective evaluation of whether the women did Sanhujori well or not, the rate of 'did Sanhujori wrongly' was the highest rank in each child where as general woman 'did Sanhujori well' at the first child, 'moderate' at the second and third child and 'did Sanhujori wrongly' at the 4th and fifth child. The health status implies both subjective health status women perceived and the rate of complaints of physical symptom distress women are experiencing presently. The respondents of 82.5% perceived them as unhealthy or sick and 68.9% of women complained more than two symptoms. Mean number of physical symptom distress women complained was 2.33. The main sites of physical symptom distress were upper & lower extremities 69.1% including knee and hand, whole body 19.1%, neck 3.7%, waist & shoulders 2.7% respectively. The characteristics of the symptoms were mostly pain 60%, swelling 19.8%, rigidity & deformity 7.9% respectively, sensation of heat 6.8% and weakness 1.7%. Women perceived the etiology of the chronic arthritis as stress 25.8%, 'did Sanhujori wrongly' & overwork 23.4% respectively, genetic 12.9%, malnutrition, 4.8%, and aging process 3.2%. There were significant positive correlation between subjective health status and the period of Sanhujori after delivery of the second child(r=-0.22) and negative correlation with the number of child at the level of 5% of significance statistically(r=0.27). There were significant negative correlation between the rate of complaints of physical symptom distress and the subjective evaluation whether she did Sanhujori well or not at the level of 5% of significance statistically(r=-0.23). And the rate of complaints of physical symptom distress in the group of women who experienced abortion was significantly higher than that of women who did not experience it at the level of 5% significance statistically(t=2.00) In conclusion, this finding reconfirmed the possible relationship between health status of chronic arthritis female patient and the experience of Sanhujori after delivery & abortion. It provides a challenge to the professional care givers to research further on the effects of Sanhujori on the health status, health recovery after abortion or delivery from the various aspects through the crosssectional and longitudinal research for the refinement of the reality of not only as cultural phenomenon but as conceptual model for the appropriateness of intervention and quality of care for desirable health outcomes.

• Journal of Society of Preventive Korean Medicine
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• v.1 no.1
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• pp.149-165
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• 1997

In order that, investigating the feature of patients suffering arthritis, analysing its contents, and grasping a Primary factor affecting it, I might offerbasic datas which could help to plan and perform healthy affairs to thake precautions beforehand, I have investigated, analysed, and studied a total of 320 patients suffering arthritis, who have received physiotherapy in hospital located in Teaegu area for five months, from November 1 1995 to March 30 1996, of which summary and conclusion is this. 1. The general feature of patients in investigative objects In the distribution of the distinction of sex, men accounted for 26.9% and women, for 73.1%, and, in the fistribution of age, 60-year-old or more, most for 27.2% and from 20 to 29 years old, least for 14.0%. In the distinction of a vocation, housewives most accounted for 34.7% and students(jobless men), least for 19.3%. In the distinction of a matrimonial state, married persons most accounted for 76.7% and people living alone(divorce, separation by death, separation), least for 11.4%. In the distinction of an economic state, the middle classes most accounted for 73.5% and the upper classes, least for 2.9%. In the distinction of their academic careers, graduates of a primary school most accounted for 26.9% and graduates of university, for 14.1%, of which patients, having the ability to decode the national language, reached to 11.3%. In the distinction of the house form, people living in independent houses most accounted for 76.4% and residents in apartment(having an elevator), least for 9.4%. 2. In the distribution of the recurring state in the distinction of the feature, the recurring group was more than the group of patients falling that ill at first as 62.2% and in the distinction of the feature of the recurring group, the recurring group turned high in case of men being from 50s to 60s years old or more, people living alone (divorce, separation by death, separation), students (joblessmen), people working in farming, stockbeeding, forestry, fisheries, a simple labour, graduates of a primary school I having the ability to decode the national language, the upper classes, people part two years since they begined to suffer arthritis, people who had members having ever experienced arthritis among families. 3. In the distribution of arthritis on the distinction of bodily pars, a knee articulation most accounted for 50.2% and the articulation of fingers, for 8.8%, wile the simultaneous, several parts (multiple) accounted for 35.1%. In the distinction of the feature, arthritis of a knee turned high in case of men being from 20s to 30s years old, unmarried persons, people having academic careers of university, the middle classes, residents in apartment (having stairs). In the dictnction of a feature the case of several parts (multiple) turned high in case of women being from 50s to 60s years old or more, people living alone (divorce, separation by death, separation), people having the ability to decode th. national language, the graduates of a primary school, the upper classes, residents in apartment (having elevator). 4. In the distribution of arthritis on e distinction of a contracting term, two years or more most accounted for 51.6% and the case of contacting from one year to two years, for 15.3%. Analysing the distinction of the feature, the case of two years or more turned high in case of women being from 50s to 60s years old or more, people living alone (divorce separation by death, separation), the upper classes, people having the ability to decode the national language, residents in apartment (having elevator). 5. In the distribution of an treatment institution before patients came to help, their not curing most accounted for 39.1%, general, orthopedic, neurological surgery (physical therapy), for. 20.0%, and th. therapy of Chinese medicine (acupuncture, moxacautery, Chinese medicine), for 17.5%, and a pharmacy (medical therapy), for 13.4%. The case of patients not curing, in the distinction of a feature, turned high in case of men 20s years old, unmarried, the lower classes, people having academic careers of university, residents in apartment (having elevator). 6. In e distribution of the extent of satisfaction with treatment, common most accounted for 54.4% and some satisfaction, for 32.8%. The case of common, in the distinction of a feature, turned high, in case of men living alone from 50s to 60s years old (divorce, separation by death, separation), married persons, the upper classes, people having academic careers of university, residents in independent house, residents in apartment (having elevator), 7. In the distribution of the degree of knowledge of the cause of arthritis, patients knowing that the cause is to use very much a articulation in normal times most accounts for 60.1%, and patients knowing the state of short nutrition as a cause, for 2.5%. The case of patients knowing that the cause is to use very much in normal times, in the distinction of a feature, turned high in·case of ment being 20s and 60s years old or more, unmarried persons, e lower classes, people having the ability to decode. the national language, people having academic careers of university, residents in apartment (having stairs), 8. In the distribution of the state of physical exercise before arthritis contracted, patients exercising very much on the whole most accpimend for 40.3%, and patients not exercising, for 34.7%. The case of patients exercising very much on the whole, in the distinction of the feature, turned high in case of men being from 50s to 60s years old or more, people living alone(divorce, separation by death, separation), the lower classes, people having the ability to decode the national language, graduates of a primary school, residents in apartment (having elevator). 9. In the taste of patients suffering from arthritis, while the group of patients falling that ill at first and the recurring group didn't smoke cigarets, during alcohol and coffee on the whole, and the group of patients falling once again that ill drank a cup of distilled linquor and three cup of coffee or more on the whole per one day, and the group of patients falling that ill at first liked sort of vegetables and the recurring group liked very much sons of vegetables and fresh and meat in their loving food normal times. 10. Analysing the distribution on the dining table used by patients and the structure of a powder room, at first, in the structure of a powder room, the group of patients filling that ill have a toilet stool using as their sits, and a Bush toilet on the whole, and the recurring group, a toilet stool using as their sits and conventional type, and in the structure of a dinning table, the group of patients falling that ill at first and the recurring group turned high, each as 66.9% and 6.3%, who have a dining table carring here and there. 11. In the distribution of patients of arthritis in relation to stress, the case that they feeled severly symptoms of arthritis when thay got stress, turned high, each, as 78.6% in the recurring poop, and the case not knowing, as 61.5% in the first group. In the extent of stress normal times, the case that they got much stress on the whole turned high, each, as 72.4% in e recurring group, and the care that got less stress on the whole, as 60.0%. 12. In the distribution on the distinction of symptoms and impedimental extent, the recurring group turned high in each variable. Analysing the feature of the recurring group, in the distinction of symptoms, the case that they fooled much that the node of an articulation is stiff, turned high, as 71.6, and in the distinction of treatment before. patients came to helpk, the theraphy of Chinese medicine (physical theraphy), as 84.4%, the theraphy of Chinese medicine (acupuncture, moxacautery, Chinese medicine), as 73.2%, and in the distinction of the satisfing extent on treatment, the case of comman, as 72.3%, and in the cause of arthritis, the case not recruiting their health after a birth, as 68.5%, and the case not recovering wholely an articulation having got hurt, as 62.8%, and in the state of physical exercise before they begined suffering from arthritis, the case exercising very much on the whole, (as 74.2%), and in the extent of subjective impediment, the case of not being able to act almost, as 66.7%, the case of acting but feeling some hard, as 66.3%. 13. The correlation in variables in relation to arthritis Analysing realted variables, the recurring frequency showed correlation with such as the extent that patients got stress normal times, and the exercising state before suffering arthritis, and showed contra-correlation with academic careers, the wights, coffee. The cigaret, e loving food of taste, showed corralation with the weight, stature, alcohole as the loving food of taste. On the basis of this result medical members of heal, who are related to the regular education, public education or development of this program, should be concerned to prevent orthris.