• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.1-6
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• 1957

The mobilities and the electrophoretic phenomena of human serum albumin, and of horse serum albumin, etc., on paper were reported, but there is no information about the mobility and the electrophoretic phenomena of ovalbumin. In this study they are determined and considered at various time durations. The mean value of this mobility is compared with the value determined by the electrophoresis in solution. Also, the mobilities of the electroendosmotic flow, which affect on the mobility seriously, are determined at various time durations. Apparatus and method used, are a closed system type and a method with electrode vessels. It is concluded that: 1) The mobilities of ovalbumin have the nearly constant mobilities at six and eight hours of time durations, but it decreases at ten hours of long time duration. Their mean value is (0.243 ${\pm}$ 0.003)cm./hr./v./cm. toward anode at pH 8.0. 2) Under these experimental conditions, ovalbumin cannot be separated into three fractions (A1, A2, A3) on paper. 3) Most of the factors, which affect on the mobility, are fixed by the initial experimental conditions, but the electroendosmotic flow due to the characteristic capillarity of paper is measured. Then, the mean value of its mobilities shows the good constancy, and the value is (0.073 ${\pm}$ 0.0003)cm/hr./v./cm. toward cathode at pH 8.0. 4) By the above facts, if the same paper and the same experimental conditions are chosen, it may be preferred to determine the mobility of the electroendosmotic flow once time, even when many observations are required.

• Journal of the Korean Ceramic Society
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• v.49 no.6
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• pp.620-624
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• 2012

The role of moisture remaining inside the deposition chamber during the formation of the cubic boron nitride (c-BN) phase in BN film was investigated. BN films were deposited by an unbalanced magnetron sputtering (UBM) method. Single-crystal (001) Si wafers were used as substrates. A hexagonal boron nitride (h-BN) target was used as a sputter target which was connected to a 13.56 MHz radiofrequency electric power source at 400 W. The substrate was biased at -60 V using a 200 kHz high-frequency power supply. The deposition pressure was 0.27 Pa with a flow of Ar 18 sccm - $N_2$ 2 sccm mixed gas. The inside of the deposition chamber was maintained at a moisture level of 65% during the initial stage. The effects of the evacuation time, duration time of heating the substrate holder at $250^{\circ}C$ as well as the plasma treatment on the inside chamber wall on the formation of c-BN were studied. The effects of heating as well as the plasma treatment very effectively eliminated the moisture adsorbed on the chamber wall. A pre-deposition condition for the stable and repeatable deposition of c-BN is suggested.

• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.1
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• pp.3642-3654
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• 1975

The purpose of this thesis is to derive a unit hydrograph which may be applied to the ungaged watershed area from the relations between directly measurable unitgraph properties such as peak discharge(qp), time to peak discharge (Tp), and lag time (Lg) and watershed characteristics such as river length(L) from the given station to the upstream limits of the watershed area in km, river length from station to centroid of gravity of the watershed area in km (Lca), and main stream slope in meter per km (S). Other procedure based on routing a time-area diagram through catchment storage named Instantaneous Unit Hydrograph(IUH). Dimensionless unitgraph also analysed in brief. The basic data (1969 to 1973) used in these studies are 9 recording level gages and rating curves, 41 rain gages and pluviographs, and 40 observed unitgraphs through the 9 sub watersheds in Nak Oong River basin. The results summarized in these studies are as follows; 1. Time in hour from start of rise to peak rate (Tp) generally occured at the position of 0.3Tb (time base of hydrograph) with some indication of higher values for larger watershed. The base flow is comparelatively higher than the other small watershed area. 2. Te losses from rainfall were divided into initial loss and continuing loss. Initial loss may be defined as that portion of storm rainfall which is intercepted by vegetation, held in deppression storage or infiltrated at a high rate early in the storm and continuing loss is defined as the loss which continues at a constant rate throughout the duration of the storm after the initial loss has been satisfied. Tis continuing loss approximates the nearly constant rate of infiltration (${\Phi}$-index method). The loss rate from this analysis was estimated 50 Per cent to the rainfall excess approximately during the surface runoff occured. 3. Stream slope seems approximate, as is usual, to consider the mainstreamonly, not giving any specific consideration to tributary. It is desirable to develop a single measure of slope that is representative of the who1e stream. The mean slope of channel increment in 1 meter per 200 meters and 1 meter per 1400 meters were defined at Gazang and Jindong respectively. It is considered that the slopes are low slightly in the light of other river studies. Flood concentration rate might slightly be low in the Nak Dong river basin. 4. It found that the watershed lag (Lg, hrs) could be expressed by Lg=0.253 (L.Lca)0.4171 The product L.Lca is a measure of the size and shape of the watershed. For the logarithms, the correlation coefficient for Lg was 0.97 which defined that Lg is closely related with the watershed characteristics, L and Lca. 5. Expression for basin might be expected to take form containing theslope as {{{{ { L}_{g }=0.545 {( { L. { L}_{ca } } over { SQRT {s} } ) }^{0.346 } }}}} For the logarithms, the correlation coefficient for Lg was 0.97 which defined that Lg is closely related with the basin characteristics too. It should be needed to take care of analysis which relating to the mean slopes 6. Peak discharge per unit area of unitgraph for standard duration tr, ㎥/sec/$\textrm{km}^2$, was given by qp=10-0.52-0.0184Lg with a indication of lower values for watershed contrary to the higher lag time. For the logarithms, the correlation coefficient qp was 0.998 which defined high sign ificance. The peak discharge of the unitgraph for an area could therefore be expected to take the from Qp=qp. A(㎥/sec). 7. Using the unitgraph parameter Lg, the base length of the unitgraph, in days, was adopted as {{{{ {T}_{b } =0.73+2.073( { { L}_{g } } over {24 } )}}}} with high significant correlation coefficient, 0.92. The constant of the above equation are fixed by the procedure used to separate base flow from direct runoff. 8. The width W75 of the unitgraph at discharge equal to 75 per cent of the peak discharge, in hours and the width W50 at discharge equal to 50 Per cent of the peak discharge in hours, can be estimated from {{{{ { W}_{75 }= { 1.61} over { { q}_{b } ^{1.05 } } }}}} and {{{{ { W}_{50 }= { 2.5} over { { q}_{b } ^{1.05 } } }}}} respectively. This provides supplementary guide for sketching the unitgraph. 9. Above equations define the three factors necessary to construct the unitgraph for duration tr. For the duration tR, the lag is LgR=Lg+0.2(tR-tr) and this modified lag, LgRis used in qp and Tb It the tr happens to be equal to or close to tR, further assume qpR=qp. 10. Triangular hydrograph is a dimensionless unitgraph prepared from the 40 unitgraphs. The equation is shown as {{{{ { q}_{p } = { K.A.Q} over { { T}_{p } } }}}} or {{{{ { q}_{p } = { 0.21A.Q} over { { T}_{p } } }}}} The constant 0.21 is defined to Nak Dong River basin. 11. The base length of the time-area diagram for the IUH routing is {{{{C=0.9 {( { L. { L}_{ca } } over { SQRT { s} } ) }^{1/3 } }}}}. Correlation coefficient for C was 0.983 which defined a high significance. The base length of the T-AD was set to equal the time from the midpoint of rain fall excess to the point of contraflexure. The constant K, derived in this studies is K=8.32+0.0213 {{{{ { L} over { SQRT { s} } }}}} with correlation coefficient, 0.964. 12. In the light of the results analysed in these studies, average errors in the peak discharge of the Synthetic unitgraph, Triangular unitgraph, and IUH were estimated as 2.2, 7.7 and 6.4 per cent respectively to the peak of observed average unitgraph. Each ordinate of the Synthetic unitgraph was approached closely to the observed one.

• Journal of Chest Surgery
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• v.36 no.12
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• pp.904-910
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• 2003

Thoracoscopic bullectomy (VATS-B) is now the preferred treatment for spontaneous pneumothorax despite of higher recurrence rate than open thoracotomy. Several methods have been used to prevent this problem. The effectiveness of staple line reinforcement (SLR) in VATA-B using endostaplers was assessed by clinical and experimental study. Meterial and Method: In experimental study, canine lungs were harvested immediately (group I N=5) and 48 hours (group II N=5) after stapling. The pressures at which initial air leaks occurred were measured. In clinical study from February 1997 to March 1999, 106 procedures in 104 patients undergoing VATS-B for spontaneous pneumothorax were classified into two groups according to the presence of SLR and were compared. Result: The average pressure of the initial air leakage was significantly higher in SLR than that of staples alone (18$\pm$1.6 vs 48$\pm$3 mm Hg in group I; 23.8$\pm$1.9 vs 54$\pm$4.6 mm Hg in group II, p<0.001). In the clinical data, there were significant differences seen in the duration of drainage, the total length of endostaplers used, and the duration of the postoperative hospital stay between patients with staple alone and patients with SLR (4.4$\pm$1.4 vs 3.1$\pm$1.1 days in duration of drainage, 92.3$\pm$28.1 vs 71.1$\pm$30.6 mm in total length of endostaplers used, 5.9$\pm$1.9 vs 4.6$\pm$1.7 days in postoperative hospital stays, p<0.001). Conclusion: SLR was effective for preventing prolonged air leakage and responsible for shorter hospital stays after VATS-B for the treatment of spontaneous pneumothorax.

• Quality Improvement in Health Care
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• v.2 no.1
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• pp.68-84
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• 1995

Background: Guideline for practice is useful because it can be the standard for assessment and way to improve quality. We need to take account of expert opinion and consensus as well as scientific evidences to develope practice guideline because it should be practical. Delphi method has been developed to gather opinions from experts fairly. This study was designed to develop practice guideline and apply it to practices as a method to improve quality in primary medical care. Methods: Hypertension(in adults over 18 years old) was selected as a target problem. Self questionnaires about management of hypertensive patients were developed by a researcher with advice of 11 experts. The questionnaires were designed to response as a 5 pont scale. The results of previous questionary were given to respondents in second and third questionnaires. If needed, the questionnaires were changed on the previous responses. The items with medium greater than or equal to 4 point in 1st and 2nd responses were accepted in guideline. The items with medium lesser than or equal to 3 point were questioned again about whether they can be excluded or not. The criteria for assessment was made with reference to guideline and applied to 85 hypertensive patients of 9 family practitioners. At 3 months after practice guideline had been given to family practitioners, performance of same practitioners was assessed with 36 new hypertensive patients. Results: 23 professors in family medicine, 22 family practitioners and 6 cardiologists, responded among 50, 50, 15 respectively. Practice guideline with 33 items was developed as a result of 3 times questionaires. The difference of responses between professors in family medicine, family practitioners and cardiologists was not significant. Performance of practice was improved in diagnosis, history taking about 6 fields, laboratory examination and decision making about time of pharmaceutical prescription. It was not improved in physical examination, life style modification, method of pharmaceutical prescription, choice of initial antihypertensives and history taking about duration of disease and diet habit. It was decreased in history taking about psychosocial factors. The assessment scores were low in history taking, physical examination and life style modification before and after use of practice guideline. Conclusion: Practice guideline for hypertension could be developed by Delphi method. Performance of practice improved partially after use of guideline.

• Journal of Chest Surgery
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• v.41 no.6
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• pp.724-728
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• 2008

Background: The purpose of this study was to identify factors associated with recurrent pneumothorax after wedge resection in primary spontaneous pneumothorax in our hospital. Material and Method: Two hundred thirty-five consecutive patient (98% males; mean age, $23.9{\pm}4.5$ years) who had undergone video-assisted thoracoscopic surgery (VATS) were reviewed retrospectively. The two groups were divided as follows: group A, non-recurrent patients (225 patients [96%]); and group B, recurrent group (10 patients [4%]); the risk factors were compared between the two groups. The single and multiple factors that influenced the recurrence rate were analyzed using Cox's proportional hazard model. Result: There were no significant differences between the recurrent and non-recurrent groups in terms of gender, smoking, site of recurrence, degree of collapse, operative time, and number or weight of resected bullae. The recurrence rate was significantly more common in the following: younger ages, increased height/weight ratio, longer initial air leakage period, and shorter duration of chest drainage. Early aggressive exercise (<30 days) of patients after wedge resection increased the tendency for recurrence. Conclusion: Thoracoscopic wedge resection does not have a higher recurrence rate than open thoracotomy. However, young age, height/weight ratio, continuous air, and duration of chest tube placement were risk factors for a recurrent pneumothorax.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.22 no.1
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• pp.40-46
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• 2011

Background and Objectives : Vocal fold bowing is an organic voice disorder that is associated with an abnormal structure of the vocal folds whereas vocal fold polyp is a functional voice disorder caused by an abnormal use of the vocal folds. Both types of vocal folds share a common property in that they make one's voice breathy or strained. The purpose of this study is to compare voice from two types of vocal folds and to offer information of clinical importance. Materials and Method: Vocal fold bowing and vocal fold polyp groups consisted of 7 male subjects, respectively. All subjects recorded /a/ in the state of measuring MPT (maximum phonation time), repeating 3 times, by a voice recorder (48 kHz sampling rate; 24 bit quantization). They answered the questions of K-VHI. Time domain parameters (such as perturbation parameters including HNR, Jitter, etc.) were calculated for the whole duration of /a/ and those of the frequency domain were measured in initial 40 ms and stable 40 ms of /a/, respectively. Mann-Whitney V-test was used for the time domain parameters and K-VHI survey, and Wilcoxon signed rank test was applied to the frequency domain parameters (H1, H2, H1-H2). Results: For K-VHI survey and the time domain analysis, there was no significant difference between bowing and polyp group. For frequency domain analysis, H1 and H2 showed a significantly different result between two groups. Vocal fold bowing group has longer duration and lower intensity than that of vocal fold polyp group in the 'aspirated interval', which could be observable prior to ordinary vowel oscillation. Conclusion: Both groups seem to show breathy voice. This could be referred on the basis of the value of H1-H2. The K-VHI survey says that subjects with vocal fold bowing feel more uncomfortable than subjects with vocal fold polyp.

• Journal of Chest Surgery
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• v.32 no.3
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• pp.276-280
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• 1999

Background: Post-pneumonectomy empyema(PPE) is an uncommon but a serious complication. The management remains as challenge for general thoracic surgeons. Material and Method: During the period of January 1990 to December 1996, we evaluated the results of 20 patients with post-pneumonectomy empyema. Result: Sex ratio were 15 male and 5 female patients with mean age of 41.5${\pm}$21.5 yrs. The occurrence ratio of left to right side was 8:12. The most common disease for prior pneumonectomy was pulmonary tuberculosis. The duration between pneumonectomy and PPE was variable in 1 month to 6yrs. Fever was the most frequent symptom and S. aureus was the most frequent pathogen. In 13 cases, there were combined with BPF. Four patients underwent trans-sternal closure, and Clagett procedure was performed. There was one recurrence that later underwent muscle plombage and omentopexy later. Nine patients underwent omentopexy, muscle plombage and thoracoplasty. There were 7 cases that were not combined with BPF. All 7 patients underwent thoracoplasty, and two of them were combined with muscle plombage. Mean follow-up duration is 40${\pm}$32.3 months. There were no late deaths nor recurrences of PPE. Conclusion: We conclude that early diagnosis and proper drainage in PPE patients are important in its initial stage of management, and also management is completely achieved in thoracoplasty with muscle plombage or omentopexy.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.22 no.3
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• pp.153-166
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• 2009

Objectives : This study was planed to evaluate clinical status of the alopecia patients who had visited Korean medicine clinic. And the result from this study would provide a standard in Korean medical diagnostic and classification method of alopecia. Methods : Clinical records of 183 patients with alopecia seen from January 2004 to April 2005 at Korean medical clinic was examined. They were classified into 4 different types according to chief complains besides alopecia by 2 Korean medical doctors. Results and conclusions : We made clinical analysis of patients of alopecia from January 2004 to April 2005. Among the alopecia patients who visit Korean medical clinic, people age between 20 and 30 had high ratio. The duration from the recognition of initial hair loss to the time of the first visit to the Korean medical clinic was less than 12 months in 20.8%(38/138), and less than 60 months in 72.2% (132/183). The condition of alopecia was more worse than other alopecia patients who visit the west medical clinic. Also the ratio with increased temperature of face or scalp is chief complaint except alopecia in alopecia patients was high in men and the ratio with dysfunction of digestive system or chronic weakness was high in women. Among the incidence of alopecia, the androgenic alopecia was most in number; 43.7%(80/183) and the sex distribution showed 83 men and 100 women.

• Journal of Korean Neurosurgical Society
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• v.30 no.6
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• pp.761-768
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• 2001

Objective : To describe the underlying causes, surgical results, and prognostic factors in thoracic stenosis causing myelopathy, retrospective analysis for 28 cases of thoracic stenosis with surgery was performed Materials & Method : Twenty-eight patients(male, 15 ; female, 13) who underwent decompressive surgery for thoracic stenosis between 1987 and 1997 were analyzed. The mean age was 49 and the mean follow-up was 30.6 months. Statistical analysis with $SPSS^{(R)}$ was performed. Chi-square test was used for the analysis of relationship between subjects and multivariate analysis with general linear model was used to find prognostic factors. Result : Degenerative spondylosis was the most common cause, and three cases were associated with systemic diseases. Decompressive laminectomy was done in 23 cases, anterior decompression in four cases, and combined decompression in one case. Ossification of ligamentum flavum was found in 18 cases, facet hypertrophy in 13, ossification of posterior longitudinal ligament in six, and ventral spur in four. Postoperatively, 16 patients improved functionally and 4 patients worsened. The group of which initial symptom duration was less than two years showed better result(p=0.003). The group with sufficient decompression and no additional proximal stenosis had better outcome(p=0.002, p=0.001). Conclusion : Chronic myelopathy caused by thoracic stenosis can be reversible with appropriate decompression.