• The Journal of the Korean life insurance medical association
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• v.2 no.1
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• pp.152-181
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• 1985

A statistical analysis on the cardiothoracic ratio in insurance medicine was carried out for 5,200 insured persons who were medically examined including photofluorography of the chest at the Honam medical department, Dong Bang life insurance Company, Ltd from November, 1979 to August, 1984. The results were as follows: 1. The mean value of the cardiothoracic ratio in all of the insured was $44.2{\pm}4.3%$. The mean value of the cardiothoracic ratio was $43.1{\pm}4.1%$ in all males and $45.2{\pm}4.2%$ in all females, and the difference of the values between males and females showed statistical significance(P<0.001). In each age group, the mean value of the cardiothoracic ratios of female was higher than that of male without exception and the difference of the values between males and females showed statistical significance(P<0.001). The mean value of the cardiothoracic ratio showed gradual increase with age from the second to sixth decade in male(P<0.05 or 0.001 after fourth decade) and from the second to seventh decade in female(P<0.05 or 0.001 from the second to sixth decade). 2. Correlation between both sexes and among age groups relating to the cardiothoracic ratios of the insureds seen to be a physiological phenomenon of the cardiac size and should be considered on the rating of the cardiothoracic ratio. Based on the correlation above mentioned and an author's assumption that the incidence of normal and abnormal cardiothoracic ratios in each age group would show the same rate in male and female, author prepared a modified rating table from the existing table; in male group the existing rating table is used and in female group the ratings of 0, 30-50, 50-100 and 100-D are to calculate by the cardiothoracic ratio of 51%or under, 52-56%, 57-61% and 62% or over respectively in the age group below 39, by the cardiothoracic ratio of 52% or under, 53-57%, 58%-62% and 63% or over respectively in the age group of 40-49, by the cardiothoracic ratio of 53% or under, 54-58%, 59-63% and 64% or over respectively in the age group over 60. 3. The relative frequency distribution polygons of the cardiothoracic ratio of both sexes drawn in a pair on one coordinate plane revealed lying in juxtaposition each other horizontally and showed the shifting of females polygon to male's one toward the direction of greater value of the cardiothoracic ratio at a short distance which increased gradually with age. 4. The minimum cardiothoracic ratio was 31.2% and the maximum cardiothoracic ratio was 63.6% in all of the insured. 5. In each age group, no significant sex difference was found in the relative frequency distribution of ratings by the cardiothoracic ratios of 5,200 insureds by using the rating table modified by author, while significant sex difference was found by using the existing rating table.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.46 no.6
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• pp.379-384
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• 2020

Objectives: We sought to identify a clinically useful method of analyzing orbital dystopia to aid in diagnosis and treatment planning and to quantify vertical discrepancies in eye level and variations in canthal tilt in Koreans. Patients and Methods: In 76 Korean patients with a mean age of 23.12 years, mean differences in the level of the pupils, lateral canthi, medial canthi, and canthal tilt were measured. The difference in pupil level was calculated from the perpendicular lines drawn from the midpupil area of each eye to the midline of the face to determine the amount of skeletal discrepancy of the eye. Soft tissue discrepancies were determined according to the vertical difference between the lines drawn from the lateral or medial canthus of each eye perpendicular to the midline of the face. The canthal tilt was determined from the inclination of a line connecting the lateral and medial canthi, then classified as class I, II, or III. Results: Mean differences in pupil level, medial canthi, and lateral canthi were 1.57±1.10 mm, 1.14±1.07 mm, and 2.03±1.64 mm, respectively. The mean degree of canthal tilt were 8.45°±3.53° for the right side and 8.42°±3.81° for the left side. No study participants presented with class III canthal tilt. The mean canthal tilt values for those with class I tilt were 3.21°±1.68° for the right side and 3.18°±1.63° for the left side, while, for those who had class II tilt, the values were 9.60°±3.66° for the right side and 9.54°±2.99° for the left side. Conclusion: The presented diagnostic method of orbital dystopia can be used to effectively establish a treatment plan that takes into consideration the patient's skeletal and soft-tissue discrepancies.

• MALSORI
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• no.35_36
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• pp.1-12
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• 1998

This study aims to investigate the prosodic characteristics of Korean discourse sentences, especially focusing the initial and final part of a sentence. 50 disourse sentences were read in two different styles; one, sentence by sentence, the other, continuous of all 50's. First, we tried to get two kinds of ratios from the acoustic results: first, ratio of the final syllable to the initial syllable in first word in a sentence; second, ratio of the final syllable to the initial syllable in last word in a sentence. We, then, calculated statistical values of the ratios including mean, standard deviation, minimum, maximum, and p-values in t-test. With respect to duration, there were little difference between two different styles. If any, we could see tiny unharmonious durational aspect in the initial of continuous reading. More concisely, there could be observed some deviation from standard. In case of F0, there was prominent statistical difference between ratios of last words in two styles. This difference might play a role as a prosodic feature. Energy seems to show similar pattern with that of F0. The results showed that final syllable in last word was pronounced with about 85 % of initial syllable in the same context and the last words in continuous speech were strongly articulated compared with those of sentence by sentence reading.

• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3816-3823
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• 2022

This work analyzed the dosimetric difference between the intensity modulated radiotherapy (IMRT), partial/single/double-arc volumetric modulated arc therapy (PA/SA/DA-VMAT) techniques in treatment planning for treating more than one target of lung cancer at different isocenters. IMRT and VMAT plans at different isocenters were created systematically using a Harold heterogeneous lung phantom. The conformity index (CI), homogeneity index (HI), gradient index (GI), dose-volume histogram and mean and maximum dose of the PTV were calculated and analyzed. Furthermore, the dose-volume histogram and mean and maximum doses of the OARs such as right lung, contralateral lung and non GTV were determined from the plans. The IMRT plans showed the superior target dose coverage, higher mean and maximum values than other VMAT techniques. PA-VMAT technique shows more lung sparing and DA-VMAT increases the V_5/10/20 values of contralateral lung than other VMAT and IMRT techniques. The IMRT technique achieves highly conformal dose distribution to the target than other VMAT techniques. Comparing to the IMRT plans, the higher V_5/10/20 and mean lung dose were observed in the contralateral lung in the DA-VMAT.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.4
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• pp.335-341
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• 2019

Purpose: Chemically strong-acids (HF and $HCl/H_2SO_4$) dual etching implant surfaces have higher strengths of osseointegration than machined implant surfaces. However, the dual acid treatment deteriorates the physical properties of the titanium by weakening the fatigue resistance of the implant and causing microcracks. The removal torque comparison between the dual-acid etched (hydrochloric acid, sulfuric acid, HS) and single-acid etched implants (hydrochloric acid, H) could reveal the efficiency of implant surface acid treatment. Materials and methods: Nine $3.75{\times}4mm$ dual-acid etched SLA implants and nine single-acid etched SLA implants were inserted into New Zealand rabbit tibias. After 10 days, removal torque, roughness, and wetting angle were measured. Results: Mean removal torque values were as follows: Mean removal torque were 9.94 Ncm for HS group and 9.96 Ncm for H group (P=.995). Mean surface roughness value were $0.93{\mu}m$ for HS group and $0.84{\mu}m$ for H group (P=.170). Root mean square roughness (RSq) values were $1.21{\mu}m$ for HS group and $1.08{\mu}m$ for H group (P=.294), and mean wetting angle values were $99^{\circ}$ for HS group and $98^{\circ}$ for H group (P=.829). Statistical analysis showed no significant difference between the removal torques, roughness, or wetting angles of the two groups. Conclusion: In this experiment, we found no significant difference in removal torque, roughness, or wetting angle between dual-acid etched and single-acid etched implants.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.4
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• pp.85-95
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• 1998

In this paper, a new watermarking method for a copy protectionof images is proposed. The proposed method adaptively embeds a watermark in the frequency domain of images using human visual system model. For this purpose, the Just Noticeable Differences(JNDs) of each frequency coeffeicient value of a luminance plane is first found using Watson and Solomon's visual system model. An invisible maximum watermark value with is different in every position according to the characteristics of images is determined usig JND and Minkowski metric. A low frequency domain is divided into two sets based on a PN-sequence to protect thewatermark from the attack. The watermarks are added to one set of coefficients and detecting a watermark, the difference between the mean values of absolute coefficient values of both sets is calculated. The embedded watermark is tested using statistical hypothesis based on test static dertermined by the ean difference. To demonstrate the perfromance of the proposed method, the new watermarking method is applied to a high frequency image and low frequency images. Experimenatal results show the watermark is invisible and robust to JPEGlossy compression and noise.

• Imaging Science in Dentistry
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• v.33 no.2
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• pp.91-95
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• 2003

Purpose : To compare the diagnostic accuracy of proximal caries detection between Kodak Insight film and the Biomedisys CDX2000HQ digital (CCD) sensor. Materials and Methods: 156 proximal surfaces of extracted teeth, 78 of which had chemical artificial caries, were used in this study. Four observers interpreted the radiographs using a five-point confidence rating scale to record their diagnoses. The results were analyzed by receiver operating characteristic curves, ANOVA and Kappa values. Result: Analysis using receiver operating characteristic curves revealed the areas under each curve which indicated a diagnostic accuracy of 0.951 in Insight and 0.952 in CDX2000HQ digital sensor. ANOVA revealed no significant differences between the two images with respect to caries detection. Kappa values indicated that the mean intra-observer agreement was 0.85 and inter-observer agreement 0.71 in conventional radiography. In digital radiography, the mean intra-observer agreement was 0.84 and inter-observer agreement 0.72. Conclusion: The results suggest that no significant difference exists between the two modalities for artificial caries detection and that CDX2000HQ was as good as Insight film for this purpose.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.3 no.2
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• pp.123-130
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• 1991

The mixed convection heat transfer from vertical inline plates has been studied numerically by the finite difference method and experimentally with Mach-Zehnder interferometer. The dimensionless spacing, $s/L_1$, the relative length, $L_2/L_1$ and the dimensionless temperature ratio, ${\Phi}_2/{\Phi}_1$ are varied parametically. The lower plate mean Nusselt numbers show same values as $s/L_1$, ${\Phi}_2/{\Phi}_1$ and $L_2/L_1$ increase. The upper plate mean Nusselt numbers increase as $s/L_1$ and ${\Phi}_2/{\Phi}_1$ increase, but $L_2/L_1$ decreases. The upper plate mean Nusselt number is higher than the lower plate mean Nusselt for $s/L_1$ 1.8 at Re=100, $Gr=10^4$, Pr=0.71, $L_2/L_1=0.5$ and ${\Phi}_2/{\Phi}_1=1.0$. A comparison between the experimental and numerical results show good agreement.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.154-158
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• 2007

Adsorption isotherms for chaga mushroom powder as influenced by particle size were investigated using a gravimetric technique. Samples were equilibrated in desiccators containing sulfuric acid solutions of known water activity (0.11-0.93), then placed in temperature-controlled chambers for approximately ten days. Equilibrium moisture content (EMC) of chaga mushroom powder increased with water activity in all samples. EMC was slightly greater in the samples comprised of smaller particle size, however there was no marked difference in appearance between the three samples. The chaga mushroom powder exhibited Type II behavior. When the BET model was used to determine mean monolayer values, 0.077, 0.077, and 0.070 $H_2O/dry$ solid was observed for <250, 250-425, and $425-850\;{\mu}m$ sized samples, respectively, however mean monolayer values were 0.121, 0.111, and 0.101 $H_2O/dry$ solid, respectively, when the GAB model was used. The experimental EMC values were related to the computed values from Henderson's model. The coefficient of determination and standard error for the linear regression were 0.997 and 0.003, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.189-192
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• 2001

This study was initiated in an effort to determine the normal mean and variations of the somatic cell count (SCC) in milk of buffaloes as influenced by the milking time, stage of lactation, parity and season. The buffaloes were hand milked at 13 and 11 h. interval during evening and morning respectively. On the day of milk sampling the udders were tested for mastitis by California Mastitis Test (CMT). Only those buffaloes, which were found negative in the CMT, were included in the sampling plan. The mean values for morning and evening were 1.09 (range 0.39-1.76) and $0.97(range\;0.57-2.46){\times}10^5cells/ml$, respectively which did not differ significantly. When data of the morning and evening values was compared on the basis of total cell secretion in milk, even then there was no statistical difference between the morning and the evening values, thereby suggesting that no diurnal variation existed in SCC of milk. Paritywise differences were not significant between the 1st to 5th lactation and above. Similarly stage of lactation effect, when tested at 30 day intervals, did not differ significantly. Significant (p<0.05) correlation coefficients (r) between SCC and milk yield during different stages of lactation and parity suggested that SCC per ml of milk was higher during the later stages of lactation. SCC was higher in primiparous than in multiparous buffaloes. On an average the SCC recorded was $1.0{\times}10^5cells/ml$ of milk irrespective of time of milking, parity and stages of lactation. The SCC was low during cold and hot-dry season but were high during the hot-humid season (p<0.05), the respective values being 0.76, 1.08 and $1.35{\times}10^5cells/ml$. These values were lower than the SCC already reported in cows suggesting less stressful condition of the udder of buffaloes in this study.