• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3902-3909
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• 2009

The purpose of this study was to investigate the spontaneous therapy, TENS(transcutaneous electrical nerve stimulation) and ice therapy after induction of DOMS(delayed onset muscle soreness) through application of eccentrically exercise in ralation to biceps brachii muscle of opposite-dominance. And to explain this, we analyzed VAS(visual analogue scales), peak torque, RMS(roots mean square) when exercising elbow joint. The subjects were 30 adults without any physical defect. Subjects were divided into three groups that spontaneous therapy, TENS therapy and ice therapy after DOMS induction, choosen movement could get the maximal peak torque in angular velocity of $60^{\circ}$/sec, and mearsured peak torque, RMS and VAS. 1. The VAS was significantly decreased after 3 days application of TENS than other groups(p<.05). 2. The peak torque was significantly increased after 3 days application of TENS than other groups(p<.05). 3. The RMS was significantly increased after 3 days application of TENS than other groups(p<.05). This study showed that TENS therapy application were effective treatment strategy on DOMS than spontaneous therapy and ice therapy. Therefore, it could be considered as a treatment method in the patients with DOMS.

• Journal of the Korean Institute of Landscape Architecture
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• v.24 no.3
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• pp.96-108
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• 1996

This study aimed at choosing the urban community parks such as D Kjin, Chungang, Dosan Park as the target place for this study, and at analyzing the damage level of the pavement surfaces focusing on the spaces and the materials. We devided the damage level within $1.5\times$1.5m grid int the grade from one to five points, and made use of the method of giving marks to get hold of the damage level of the pavement surfaces. Especially we took and analyze Duncan test for the spaces suffering severe damage. The result is as follows : 1. The damage of unenenness turned out to be a most excessive damage in the damage level according to the pavement materials in case of D kjin, and Chunggnag Park. Especially the concrete blocks proved to be the exessive damage in comparison with the other pavement materials, and the demolitional damage of the damage types to the most severe damage. The corner damage turned relatively out to be a heavy damage in case of Dosan Park in Seoul. 2. In the event of the damage level of pavement surfaces according to the spaces, the space which was made the more use of and which was the more concentrated, turned out to be the degree of the more excessive damage. 3. We took the Duncan test to verify the deference of the damage type between the spaces and the pavement materials of the target places for survey. The result of verification was that there was no difference of the damage type between the corner and block damage itself in case of the enterance area and the square of D kjin Park in Ch nju, and that the damage level of the pavement materials proved to be the more execssive damage than that of the spaces. The corner damage of Chungang Park in Hj ngju, showed the same result as D kjin Park in Ch nju and the uneveness didn't have any difference of damage type in all spaces. In case of Dosan in Seoul, the damage of crevice, demolition, and pumping didn't have any difference of damage type and the damage of the cross area was the most high. In conclusion, we proposed that we should get hold of whether the cause of pavement damage is caused by the defect of materials of by the construction problem including the foundation, or the unsuitableness of the method for using the pavement materials, and also that we should take a sensus of the user type and should decide a suitable design load and the necessary thickness of the pavement materials. In this study, not only we aimed at the external damage of the materials, but we tried to propose rather reasonable and developed construction method by studying the material experiment, the foundation state, and the type of using the spaces and materials, and by examining into the fundamental damaged cause.

• Journal of the Korean Society for Nondestructive Testing
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• v.16 no.3
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• pp.162-173
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• 1996

Dry magnetic particle inspection(MPI) was performed to detect the surface defects of steel ingot cast billets. Magnetic properties of several materials were characterized by the measurement of the B-H hysteresis curve. The inspection results were evaluated in terms of the magnetizing current, temperature, and the amount of magnetic particles applied to billets. Magnetic flux leakage near the defect site of interest was measured and compared with the results of calculation by the finite element method in the case of direct magnetizing current. Direct and alternating magnetizing currents for materials were deduced by the comparison of the inspections. Results of the magnetic particle inspection by direct magnetizing current were compared with those of finite element method calculations, which were verified by measuring magnetic leakage flux above the surface and the surface defects of the material. For square rods, due to the geometrical effect, the magnetic flux density at the edges along the length of the rods was about 30% of that at the center of rod face for a sufficiently large direct magnetizing current, while it was about 70% for an alternating magnetizing current. Thus, an alternating magnetizing current generates rather uniform magnetic flux density over the rods, except for the region on the face across about 10 mm from the edge. The attraction of the magnetic particle by the magnetic leakage field was nearly independent of the surface temperature of the billets up to $150^{\circ}C$. However, the temperature should have been limited below $60^{\circ}C$ for an effective fixing of gathered magnetic particles to the billet surface using methylene chloride. We also found that the amount of applied magnetic particles tremendously affected the detection capability.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.1
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• pp.15-19
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• 2005

Conventional eddy current testing has been used for the detection of the defect-like fatigue crack in the conductive materials, such as aluminum, which uses a sinusoidal signal with very narrow frequency bandwidth, Whereas, the pulsed eddy current method uses a pulse signal with a broad bandwidth. This can allow multi-frequency eddy current testing, and the penetration depth is greater than that of the conventional eddy current testing. In this work, a pulsed eddy current instrument was developed for evaluating the metal loss. The developed instrument was composed of the pulse generator generating the maximum square pulse voltage of 40V, an amplifier controlled up to 52dB, an A/D converter of 16 bit and the sampling frequency of 20 MHz, and an industrial personal computer operated by the Windows program. A pulsed eddy current probe was designed as a pancake type in which the sensing roil was located inside the driving roil. The output signals of the sensing roil increased rapidly wich the step pulse driving voltage かn off, and the latter part of the sensing coil output voltage decreased exponentially with time. The decrement value of the output signals increased as the thickness of the aluminum test piece increased.

• Archives of Reconstructive Microsurgery
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• v.16 no.2
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• pp.113-118
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• 2007

Purpose: The purpose of this work was to describe the results of treatment for motor vehiclerelated crushing injuries among children and adolescents under sixteen years in Korea. Materials and Methods: A retrospective analysis was conducted of data from children who were under sixteen year and injured foot by motor vehicles. Cases were documented 1) age at the time of injury, 2) injured site, 3) the area of accident, 4) the kind of vehicle, 5) associated injuries, 6) methods of treatment for soft tissue reconstruction and 7) complications. The relationships between the area of accident and associated injuries, and the kind of vehicle and associated injuries were analyzed using Chi-square test and Fisher exact test. Results: There were 97 children who were 15 year and younger. The mean age was 7.4 years, and 65% were boys. The left foot was more dominant side of injury (57%). Seasonal variation was seen with the number of injuries peaking during the summer (43%, p<0.05). Among the vehicles, 78.3% were the large vehicles (bus, truck or van). The where of accident was more frequent at an alley or less than two lanes of traffic. But, the relationships between the place of accident and associated injury or the kind of vehicles and associated injury were not statistically significant. The associated injury were fracture or dislocation (23 cases, 35.9%), injury of tendon (21 cases, 32.8%). There were amputation or disarticulation of foot in 8 cases (8.2%) and post-traumatic deformities such as flatfoot, hindfoot varus or valus deformities by tendon injury in 7 cases (7.2%). Conclusion: More than 50% of crushing or degloving injuries of child's foot by traffic accidents happened in boys between 5 to 9 years old. The associated injury was unrelated with size of vehicles or accident place at the time of accident. But, even though foot injury happened in an alley or one lane by small vehicles, child who hurt feet by car need thorough investigation about associated injury. If a surgeon keep in mind and treat child to associated injury necessarily, can minimize complication. Microsurgical reconstruction for soft tissue defect was prior to other methods.

• Journal of dental hygiene science
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• v.17 no.2
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• pp.175-182
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• 2017

From March 1, 2016 to August 31, 2016, 375 dental implant patients between the ages of 30 and 70 years to evaluate their subjective symptoms and satisfaction according to prosthesis methods. The collected data were analyzed using the chi-square distribution test, t-test, one-way analysis of variance, and multiple logistic regression. Of the patients with subjective symptoms of peri-implantitis, 40.5% reported food impaction, 49.1% reported bleeding, 61.1% reported pain, 61.9% reported halitosis, and the overall satisfaction level with the implants was 3.95 points. In the prosthesis methods, implant-teeth connective group showed the lowest level of the food impaction (21.3%), the pain (35.5%), and the halitosis (36.6%) (p<0.001), and the lowest bleeding was the implant single (33.8%) (p<0.05). Patient satisfaction was higher in the implant-teeth connective group (4.06 points) and the group without bone grafting (4.03 points) (p<0.01). Factor analysis showed that implant satisfaction was 0.43 times lower in the single implant group and 0.44 times lower in the implant-implant connective group than in the implant-teeth connective group. As a result of the study, it is expected that the method of extending the life of adjacent teeth and restoring the function of the tooth defect region is an implant-teeth connection method, so that it can be utilized positively through various clinical studies.

• Childhood Kidney Diseases
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• v.5 no.1
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• pp.22-29
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• 2001

Purpose : 99mTc DMSA renal scan have been widely used not only for tile evaluation of renal scars but also for the diagnosis of acute pyelonephritis. Recent studies have shown SPECT images have higher accuracy than the planar images with some controversy. We evaluated the availability of the SPECT images adding to planar images for the diagnosis of acute pyelonephritis(APN) and renal scar in children with urinary tract infection (UTI). Methods : 130 children with UTI (260 kidney units) and 22 follow-up children (44 kidney units) were included between January 1, 1997 and July 31, 1999 at Ewha University Mokdong Hospital. Planar Anterior and posterior images and SPECT axial and coronal images of 99mTc DMSA renal scan were obtained with Starcam 4000-i U.S.A. GE at 3 hours after 99mTc DMSA I.V. injection. The data were analyzed by Chi square test after Yates's correction. Results : The detection rate of the acute pyelonephritis by SPECT images was 12.3$\%$ higher than that of planar images ($47.7\%\;vs\;35.4\%$) by the patient and 6.9$\%$ higher also ($31.9\%\;vs\;25.4\%$) by the kidney unit. 18 kidney units with negative planar images had focal defect in 10 kidney units (3.8$\%$) and multifocal defect in 8 kidney units (3.1$\%$) on SPECT images, but 1 kidney unit with positive planar image had negative SPECT image. SPECT images were superior to tile planar images in 17.3$\%$. identical in 82.3$\%$ and inferior in 0.4$\%$ to planar image. The detection rate of tile renal scars by SPECT images was 13.7$\%$ higher than planar images by the patient ($68.2\%\;vs\;54.5\%$) and 6.8$\%$ higher also ($43.2\%\;vs\;36.4\%$) by the kidney unit. SPECT images were superior to the planar images in 17.3$\%$ and identical in 82.3$\%$ to planar image. Conclusion SPECT images had shown higher detection rate and better image than planar images for the diagnosis of the acute pyelonephritis and the evaluation of the renal scars. (J. Korean Soc Pediatr Nephrol 5 : 22- 9, 2001)

• Clinical and Experimental Pediatrics
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• v.52 no.12
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• pp.1364-1369
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• 2009

Purpose : To analyze abnormal ventricular activation in childhood congenital heart disease induced by postoperative changes in ventricular volume and pressure and ventricular scar formation using signal-averaged electrocardiography (SAECG). Methods : Fifty-two patients who had undergone open heart surgery (OHS) were enrolled. Patients were divided into the following 3 groups: right ventricular volume overload (atrial septal defect, group1), left ventricular volume overload (ventricular septal defect, group2), and right ventricular pressure overload (tetralogy of Fallot, group 3). The patients were monitored by standard 12-lead ECG and SAECG before and 2 months after the operation. QRS duration, QT and QTc intervals, filtered QRS (f-QRS), high frequency low amplitude potential (HFLA), and root mean square (RMS) voltage in the terminal 40 ms of SAECG were determined. Results : In the preoperative period, group1 showed significant increase in QRS (P=0.011) compared to those of the other 2 groups. In the postoperative period, group3 showed significant increase in the QTc interval (P=0.004) compared to those in the other 2 groups. SAECG parameters showed no significant differences among the groups in the pre- or postoperative period. Of the 52 patients, 12 (23%) in the preoperative period and 21 (40%) in the postoperative period had at least 1 SAECG abnormality. The prevalence of SAECG abnormalities was significantly higher in the postoperative group 2 and group 3 (preoperative: 20% versus postoperative: 28%, P<0.001, preoperative: 14% versus postoperative: 64%, P<0.001, respectively). Conclusion : Abnormal SAECG patterns may be attributed to postoperative scars, OHS itself, and/or ventricular overload.

• Journal of the Korean Wood Science and Technology
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• v.2 no.2
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• pp.8-12
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• 1974

1. If one unity is given to the prongs whose ends touch each other for estimating the internal stresses occuring in it, the internal stresses which are developed in the open prongs can be evaluated by the ratio to the unity. In accordance with the above statement, an equation was derived as follows. For employing this equation, the prongs should be made as shown in Fig. I, and be measured A and B' as indicated in Fig. l. A more precise value will result as the angle (J becomes smaller. $CH=\frac{(A-B') (4W+A) (4W-A)}{2A[(2W+(A-B')][2W-(A-B')]}{\times}100%$ where A is thickness of the prong, B' is the distance between the two prongs shown in Fig. 1 and CH is the value of internal stress expressed by percentage. It precision is not required, the equation can be simplified as follows. $CH=\frac{A-B'}{A}{\times}200%$ 2. Under scheduled drying condition III the kiln, when the weight of a sample board is constant, the moisture content of the shell of a sample board in the case of a normal casehardening is lower than that of the equilibrium moisture content which is indicated by the Forest Products Laboratory, U. S. Department of Agriculture. This result is usually true, especially in a thin sample board. A thick unseasoned or reverse casehardened sample does not follow in the above statement. 3. The results in the comparison of drying rate with five different kinds of wood given in Table 1 show that the these drying rates, i.e., the quantity of water evaporated from the surface area of I centimeter square per hour, are graded by the order of their magnitude as follows. (1) Ginkgo biloba Linne (2) Diospyros Kaki Thumberg. (3) Pinus densiflora Sieb. et Zucc. (4) Larix kaempheri Sargent (5) Castanea crenata Sieb. et Zucc. It is shown, for example, that at the moisture content of 20 percent the highest value revealed by the Ginkgo biloba is in the order of 3.8 times as great as that for Castanea crenata Sieb. & Zucc. which has the lowest value. Especially below the moisture content of 26 percent, the drying rate, i.e., the function of moisture content in percentage, is represented by the linear equation. All of these linear equations are highly significant in testing the confficient of X i. e., moisture content in percentage. In the Table 2, the symbols are expressed as follows; Y is the quantity of water evaporated from the surface area of 1 centimeter square per hour, and X is the moisture content of the percentage. The drying rate is plotted against the moisture content of the percentage as in Fig. 2. 4. One hundred times the ratio(P%) of the number of samples occuring in the CH 4 class (from 76 to 100% of CH ratio) within the total number of saplmes tested to those of the total which underlie the given SR ratio is measured in Table 3. (The 9% indicated above is assumed as the danger probability in percentage). In summarizing above results, the conclusion is in Table 4. NOTE: In Table 4, the column numbers such as 1. 2 and 3 imply as follows, respectively. 1) The minimum SR ratio which does not reveal the CH 4, class is indicated as in the column 1. 2) The extent of SR ratio which is confined in the safety allowance of 30 percent is shown in the column 2. 3) The lowest limitation of SR ratio which gives the most danger probability of 100 percent is shown in column 3. In analyzing above results, it is clear that chestnut and larch easly form internal stress in comparison with persimmon and pine. However, in considering the fact that the revers, casehardening occured in fir and ginkgo, under the same drying condition with the others, it is deduced that fir and ginkgo form normal casehardening with difficulty in comparison with the other species tested. 5. All kinds of drying defects except casehardening are developed when the internal stresses are in excess of the ultimate strength of material in the case of long-lime loading. Under the drying condition at temperature of $170^{\circ}F$ and the lower humidity. the drying defects are not so severe. However, under the same conditions at $200^{\circ}F$, the lower humidity and not end coated, all sample boards develop severe drying defects. Especially the chestnut was very prone to form the drying defects such as casehardening and splitting.