• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.423-429
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• 2018

Objective: This study was conducted to investigate the effects of WBVE on biomechanical factor analysis of drop landing jumps before and after a four week training program. Methods: Participants were divided into two group: VEG (n=5, age: $25.7{\pm}2.3yrs$, height: $170{\pm}7.6cm$, weight: $69.3{\pm}8.3kg$) and OEG (n=5, age: $24.6{\pm}3.4yrs$, height: $164{\pm}4.9cm$, weight: $58.8{\pm}9.2kg$). Ten infrared cameras (Vicon, UK) with a sampling rate of 100 Hz were used in two GRF measurement systems (AMTI, USA). Results: The variability of the center of mass was largest at the falling phase, and there was a great risk of injury when landing after the jump. Second, the jumping heights of the VEG (vibration exercise group) were higher than those of the OEG (only exercise group), regardless of training period. Third, there were significant differences in the hip joint P1 (flexion) and knee joint P2 (extension) between the exercise groups after 4 weeks of training. However, there were no significant differences among training periods or phases. Conclusion: regardless of training periods, the VEG showed increased jump height compared with the OEG, but the consistency between the jump height and the lower joint power could not be determined.

• Korean Journal of Applied Biomechanics
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• v.16 no.3
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• pp.137-148
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• 2006

The purpose of this study was to compare muscle activity in the lower extremity during walking wearing jogging and roller shoes. Twelve male middle school students (age: 15.0 yrs, height 173.7 cm, weight 587.7 N) who have no known musculoskeletal disorders were recruited as the subjects. Seven pairs of surface electrodes (QEMG8, Laxtha Korea, gain = 1,000, input impedance >$1012{\Omega}$, CMMR >100 dB) were attached to the right-hand side of the body to monitor the rectus femoris (RF), vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), tibialis anterior (TA), and medial (GM) and lateral gastrocnemius (GL) while subjects walked wearing roller and jogging shoes in random order at a speed of 1.1 m/s. An event sync unit with a bright LED light was used to synchronize the video and EMG recordings. EMG data were filtered using a 10 Hz to 350 Hz Butterworth band-passdigital filter and further normalized to the respective maximum voluntary isometric contraction EMG levels. For each trial being analyzed, five critical instants and four phases were identified from the recording. Averaged IEMG and peak IEMG were determined for each trial. For each dependent variable, paired t-test was performed to test if significant difference existed between shoe conditions (p<.05). The VM, TA, BF, and GM activities during the initial double limb stance and the initial single limb stance reduced significantly when going from jogging shoe to roller shoe condition. The decrease in EMG levels in those muscles indicated that the subjects locked the ankle and knee joints in an awkward fashion to compensate for the imbalance. Muscle activity in the GM for the roller shoe condition was significantly greater than the corresponding value for the jogging shoe condition during the terminal double limb stance and the terminal single limb stance. Because the subjects tried to keep their upper body weight in front of the hip to prevent falling backward, the GM activity for the roller shoe condition increased. It seems that there are differences in muscle activity between roller shoe and jogging shoe conditions. The differences in EMG pattern may be caused primarily by the altered position of ankle, knee, and center of mass throughout the walking cycle. Future studies should examine joint kinematics during walking with roller shoes.

• Journal of Biomedical Engineering Research
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• v.25 no.2
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• pp.137-144
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• 2004

ECG signals are often contaminated with high-frequency noise such as muscle artifact, power line interference, and others. In the ECG signal processing, especially during a pre-processing stage, numerous noise removal techniques have been used to reduce these high-frequency noise without much distorting the original signal. This paper proposes a new type of digital filter with a continuously variable cutoff frequency to improve the signal quality This filter consists of a cutoff frequency controller (CFC) and variable cutoff frequency lowpass filter (VCF-LPF). From the noisy input ECG signal, CFC produces a cutoff frequency control signal using the signal slew rate. We implemented VCF-LPF based on two new filter design methods called convex combination filter (CCF) and weight interpolation fille. (WIF). These two methods allow us to change the cutoff frequency of a lowpass filter In an arbitrary fine step. VCF-LPF shows an excellent noise reduction capability for the entire time segment of ECG excluding the rising and falling edge of a very sharp QRS complex. We found VCF-LPF very useful and practical for better signal visualization and probably for better ECG interpretation. We expect this new digital filter will find its applications especially in a home health management system where the measured ECG signals are easily contaminated with high-frequency noises .

• 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.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.2
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• pp.1-11
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• 2023

This study intended to develop a technique for quantitatively and 3-dimensionally predicting the potential failure zone and impulse that may occur when trees are fall down. The main outcomes of this study are as follows. First, this study established the potential failure zone and impulse calculation formula in order to quantitatively calculate the risks generated when trees are fallen down. When estimating the potential failure zone, the calculation was performed by magnifying the height of trees by 1.5 times, reflecting the likelihood of trees falling down and slipping. With regard to the slope of a tree, the range of 360° centered on the root collar was set in the case of trees that grow upright and the range of 180° from the inclined direction was set in the case of trees that grow inclined. The angular momentum was calculated by reflecting the rotational motion from the root collar when the trees fell down, and the impulse was calculated by converting it into the linear momentum. Second, the program to calculate a potential failure zone and impulse was developed using Rhino3D and Grasshopper. This study created the 3-dimensional models of the shapes for topography, buildings, and trees using the Rhino3D, thereby connecting them to Grasshopper to construct the spatial information. The algorithm was programmed using the calculation formula in the stage of risk calculation. This calculation considered the information on the trees' growth such as the height, inclination, and weight of trees and the surrounding environment including adjacent trees, damage targets, and analysis ranges. In the stage of risk inquiry, the calculation results were visualized into a three-dimensional model by summarizing them. For instance, the risk degrees were classified into various colors to efficiently determine the dangerous trees and dangerous areas.

• Journal of the Korean Society of Food Science and Nutrition
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• v.5 no.1
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• pp.39-51
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• 1976

We arrive at the conclusion as follows as for the connection between dietary life, hours of exercise and growth of body, based on the survey of their height, this circumference of the breast and their body weight, and the questionnaires to the pupils of 36,547 in totals (contained the primary and middle school boys and girls) in four districts(named A, B, C and D district) of Jeonlla Bug Do from April, 1970 to March, 1973. (1) The growth in height. The boys from 6 to 7 years old are nearly same in all districts, but as age increases, those of A district grow more rapidly than those of B, C and D districts, while those of B, C and D districts grow almost samely. The girls already from 6 years old on are different between A district and B, C, D district. The average of height in Jeonlla Bug Do is not different from that of Gyungi Do and whole nation in the pupils from 6 to 11 years old, and that of Japan from 6 to 7 of age, while it falls behind them as age increases. (2) The growth in the circumference of the breast. The boys from 6 to 9 years old show nearly the same tendency in all districts, after that age the boys in A district tend to grow rapidly, those in B district most fall behind, and those in C, D districts show the same tendency. Contrasted with height the growth in the circumference of the breast does not show the difference in each district so far as 14 of age, but after 15 years old it shows a little difference by falling behind of pupils in A district, while those B, C, D districts show almost the same tendency. The average of the circumference of the breast in Jeonlla Bug Do of the pupils from 10 to 11 of age is almost same to that of Gyungi Do, whole nation and Japan, but shows difference after that age. (3) The growth of body weight. The body weight of boys over-all the investigated whole age shows the superiority in A district and a little lowness in D district which is almost same to that of B, C districts. In that of girls, A district is superior in from 6 to 9 of age, and all districts are nearly same after that age. The average in Jeonlla Bug Do is one and the same to those of Gyungi Do, whole nation and Japan as in the height, but shows the great difference as years grow. (4) The dietary life of the pupils in Jeonlla Bug Do depends chiefly upon a carbohydrate and is very low in the intake of fat and protein. Connected with a view point of districts, the intake of protein is a little more in A district than in the other districts, and is nearly same in the other districts. They tend more to eat mixed food, but about 40% of them do not yet eat it. The contents and taking of lunch is bad in the highest degree, to which their parents are entirely indifferent. As far as the hours of exercise are concerned with, about 40% of all pupils must go to the school from very far, which gives them the heavy physical suffering, and especially it is remarked that the middle school boys and girls should attend school from farther than the primary school boys and girls.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.239-246
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• 2014

Purpose: This study was performed to investigate the effect of induced ametropia on static posture for body balance. Methods: Twenty subjects (10 males, 10 females) of average age $23.4{pm}2.70$ years were participated and ametropia(binocular myopia; BM, simple myopic anisometropia; SMA, binocular hyperopia; BH, and simple hyperopic anisometropia; SHA) were induced with ${pm}0.50D$, ${\pm}1.00D$, ${\pm}1.50D$, ${\pm}2.00D$, ${\pm}3.00D$, ${\pm}4.00D$, ${\pm}5.00D$, respectively. General stability (ST), weight distribution index (WDI), and fall risk index (FI) were measured using TETRAX the biofeedback systems. Each index of the body balance was evaluated for 32 seconds in each ametropic condition and those value was compared with the value in fully corrected condition. Results: The ST showed significant increase from +0.50 D under condition of BM, from +1.00 D under condition of SMA, from -1.00 D under condition of BH, and from -1.50 D under condition of SHA compared with under condition of fully corrected condition, respectively. The FI showed significant increases from +4.00 D under condition of BM, from -1.00 D under condition of BH, and from -1.50 D under condition of SHA. The WDI show no change in all ametropia condition. Conclusions: Whatever ametropia is, uncorrected refractive error could reduce the general stability of body balance and increase the falling risk.

• International Journal of Highway Engineering
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• v.8 no.1 s.27
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• pp.131-138
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• 2006

Methods of back calculation for either design procedures or elastic moduli obtained from FWD(Falling Weight Deflectometer) tests have widely been used to predict remaining life of airfield concrete pavements. Since the variation of the elastic modulus obtained from the FWD test depends on the back calculation methods, prediction of remaining life of airfield pavement using the back calculation method has not been reliable. In addition, the FWD method only concentrates on the structural integrity of the pavement without considering functional distress. In this study, a newly developed remaining life estimation procedure is proposed. This methodology includes both structural and functional consideration and suggests models and decision criteria for each stage. In order to improve the estimation procedure on remaining life of pavement, conducted the several tests on an old airfield concrete pavement. As a result, it is concluded that the load transfer efficiency on joint is better for predicting remaining life of pavement than the elastic modulus, which is commonly used. In order to verify applicability of the newly developed estimation procedure and detailed models, investigation and analysis were conducted according to the new methodology on C-airfield pavement. Finally, it is confirmed that the efficiency of the proposed method for practical application was good enough.

• International Journal of Highway Engineering
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• v.18 no.5
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• pp.57-62
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• 2016

PURPOSES : The objective of this study is to evaluate the effect of size and depth of cavities on the pavement failure using the full-scale accelerated pavement testing. METHODS : A full-scale testbed was constructed by installing the artificial cavities at a depth of 0.3 m and 0.7 m from the pavement surface for accelerated pavement testing. The cavities were made of ice with a dimension of 0.5 m*0.5m*0.3m, and the thickness of asphalt and base layer were 0.2 m and 0.3 m, respectively. The ground penetrating radar and endoscope testing were conducted to determine the shape and location of cavities. The falling weight deflectometer testing was also performed on the cavity and intact sections to estimate the difference of structural capacity between the two sections. A wheel loading of 80 kN was applied on the pavement section with a speed of 10 km/h in accelerated pavement testing. The permanent deformation was measured periodically at a given number of repetitions. The correlation between the depth and size of cavities and pavement failure was investigated using the accelerated pavement testing results. RESULTS : It is found from FWD testing that the center deflection of cavity section is 10% greater than that of the intact section, indicating the 25% reduction of modulus in subbase layer due to the occurrence of the cavity. The measured permanent deformation of the intact section is approximately 10 mm at 90,000 load repetitions. However, for a cavity section of 0.7 m depth, a permanent deformation of 30 mm was measured at 90,000 load repetitions, which is three times greater than that of the intact section. At cavity section of 0.3 m, the permanent deformation reached up to approximately 90 mm and an elliptical hole occurred at pavement surface after testing. CONCLUSIONS : This study is aimed at determining the pavement failure mechanism due to the occurrence of cavities under the pavement using accelerated pavement testing. In the future, the accelerated pavement testing will be conducted at a pavement section with different depths and sizes of cavities. Test results will be utilized to establish the criteria of risk in road collapse based on the various conditions.

• Journal of Sericultural and Entomological Science
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• v.48 no.1
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• pp.28-31
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• 2006

These experiments were executed to develop an effective rearing or collecting equipments for silkworm excreta. The rearing devices were an assembly one equipped with wheels, and its weight was reduced so that the convenience was improved. In the amount of collecting silkworm according to the size of mess, the size of 7.0*7.0 mm had 36% more than the size of 5.0*5.0 mm. However, the falling silkworm had a little (0.3%) occurred for the period of rearing the 5day-silkworm. The amount of collecting silkworm excreta using the devised collecting equipment was 19.7 kg per box at the two-floored rearing boxes. In the budget of labor hour, the devised collecting equipment have reduced the labor of traditional handy work to 65% and the productivity of labor (kg/hour) was increased to 55%. The cost of production was also decreased to 35.9%.