• The Journal of the Acoustical Society of Korea
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• v.18 no.3
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• pp.55-61
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• 1999

In this study, we have constructed the acoustic microscope using quadrature technique and analyzed the relative variation of image intensity and the quality of image by reconstructing the amplitude and phase image for surface defects with tiny hight variation. In this experiment, we have constructed the scanning acoustic microscope using the focused transducer with 3㎒ center frequency and the quadrature detector. And we have fabricated aluminum samples with round defects whose depth is different and reconstructed the amplitude and phase images for the samples. One sample has round defects with 2㎜ diameter and 100㎛ depth and the other has round defects with 4㎜ diameter and 5㎜ depth. In the result of line scanning for the sample with 100㎛ round defects, it has been shown that the variation rate of amplitude image intensity is 7% and the variation rate of phase image intensity is 89%. The phase image has better contrast than amplitude image for the sample. In contrast to this, the amplitude image has better contrast than phase image for the sample with 5㎜ depth's defects. Accordingly there is big difference between amplitude image and phase image for depth variation of defects whose boundary is 1 wavelength. Consequently the acoustic microscope using quadrature detector can be evaluated efficiently more than using envelope detector, for detecting defects which have height variation less than 1 wavelength. And also the phase image and the amplitude image can be used for detecting defects of tiny height variation with complimentary relation.

• Journal of the Korean Society of Costume
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• v.56 no.4 s.103
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• pp.65-81
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• 2006

This is the study on the costumes of Parthian Period in Persia which had powerful influences on the Occidental and Western cultures in B.C 3 to A.D 3. With different types of Parthian costumes in each period, this study shows what types of costumes people used to wear and how they were co-related with its surrounding cultures. The ancient costumes of Korea had something to do with the elements of the Northern part at that time. To make an intensive study of Korean ancient costumes, these Parthian costumes which are known to those of northern nomadic tribes are studied to provide basis elements for study between the Korean styles and the exotic styles. The basic forms of the Parthian styles were jackets and trousers. They consisted of three kinds of jackets such as those to be adjusted In the front, tunics and coats. As for trousers, they were divided into three types such as those with horizontal pleats, round-side pleats and vertical pleats. 1) The jacket to be adjusted in the front was long enough to reach the hip and fit the body reasonably tight, and its neckline was shaped into V-type. It was a very popular style among the people of high and low classes. 2) The tunics had narrow sleeves. It was a one-piece pattern which reached the knees. It was settled with a belt on the waist. Its neckline was shaped into the round but its slit was not cleat. Its styles were into tight-fit and drapery ones. 3) The coats were almost similar to the jacket to be adjusted in the front with short length, but they were entirely long and open. They appeared later than the short jackets and the people of high class seemed to wear these styles. 4) 1'rousers with horizontal pleats - They had almost horizontal pleats on them, and they were a little tight. They seemed to be the early style in the Parthian period. 5) Trousers with round side-pleats - With saggy side pleats on them, these trousers had round pleats like a drapery style. This pattern was also considered Hellenistic elements shown in the Parthian costumes. The trousers consisted of the underdrawers and the leggings (called salwar or shalwar), which is thought to emphasize its functionality for its wearer to mount a horse with more ease. 6) Trousers with vertical pleats - With straight vertical pleats on them, these trousers had some volumes and bias decorations in the middle of them. These styles were thought to be worn by the ruling class of the Parthia from early to late period.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.1
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• pp.18-24
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• 2013

Purpose: This study is performed to determine the effects of titanium cap with various sizes of pores on bone formation during guided bone regeneration (GBR). Methods: Calvaria from 10 adult male rabbits were chosen as the recipient sites. A trephine bur with a diameter of 10 mm was used to form one round groove on each side of sagittal suture of the cranium, and a round bur with a diameter of 1.5 mm was used to form 6 small holes on the inner circles of round grooves to induce bleeding. In the control group, bone graft was not conducted, and closed titanium cap was fixed in the round groove. Bone graft was not performed in groups 1 and 2, but fixed on titanium caps with 0.2 mm, and 0.5 mm sized pores, respectively. For groups 3, 4, and 5, a synthetic bone graft material (${\beta}$-tricalcium phosphate, Cerasorb$^{(R)}$, Germany) was transplanted, and titanium caps without pore, with 0.2 mm and 0.5 mm sized pore were fixed, respectively. The animals were sacrificed 4 weeks after, and clinical, radiographical, and histomorphometrical evaluation of bone regeneration was performed. Results: In all groups, there were no clinical signs of infection, inflammation or wound dehiscence. Radiographic evaluation revealed well-defined semi-circular radiopacity inside the titanium cap of groups 3, 4, and 5. Histologically, the inner surface of the hemisphere was evenly lined with newly formed bone tissue, as well as grafted bone material in the group 3. In groups 4 and 5, the insertion of connective tissue was observed along the inner surface. However, the overall surface area between the grafts with different holes yielded no statistical significance in the histomorphometrical evaluation. Conclusion: Although the total area of newly formed bone showed no significant difference, excellent bone formation tendency was observed histologically when closed caps were used with bone graft was accompanied.

• Tuberculosis and Respiratory Diseases
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• v.57 no.3
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• pp.278-283
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• 2004

The incidence of a pulmonary leiomyosarcoma as a primary lung tumor is quite rare. We report a case of primary leiomyosarcoma with a cardiac invasion in a 76 year old man. He was admitted due to left anterior chest wall pain for one month. Chest computed tomography showed a $9{\times}8{\times}10cm$ sized, large round mass in the left upper and lower lobes, and an amorphous low density lesion within the left atrium. Chest magnetic resonance imaging showed a large round mass in the left upper and lower lobes with growth into the left atrium. A diagnosis of leiomyosarcoma with prominent osteoclast-like giant cells was made based on the microscopic and immunohistochemical findings of a permanent specimen by explothoracotomy. The pathologic features of the tumor showed round mononuclear hyperchromatic cells and multinucleated giant cells that resembled osteoclasts. The immunohistochemical staining showed that the giant cells are positive for CD68 but negative for the muscle markers while the round cells were positive for the muscle marker. The patient refused further treatment and died after two months.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.722-727
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• 2016

In this study, we attempted to reduce the generation of waste acids in the electropolishing process by improving the current efficiency. The optimum conditions of the electropolishing process when using the round bus bar were determined by the Taguchi method. The current density, polishing time, electrolyte temperature and flow rate were selected as the control factors for the current efficiency in the electropolishing process. An orthogonal array was created by considering three levels for each factor and experiments were carried out. The larger-the-better SN ratios were calculated by the Taguchi method. The current density was the most important factor affecting the current efficiency and the polishing time was the least important one. The optimum conditions to minimize the generation of waste acids were a current density of $45A/dm^2$, polishing time of 4 min, electrolyte temperature of $65^{\circ}C$ and flow rate of 7 L/min. The results of the ANOVA confirmed that the effects of the current density, electrolyte temperature and flow rate are significant at the 95% confidence level. The increase in the contact area and contact force afforded by using the round bus bar improved the current efficiency which, in turn, reduced the amount of waste acids generated. Further research is planned to investigate the effect of the type of bus bar on the current efficiency.

• The Journal of Korean Society of Virology
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• v.29 no.4
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• pp.247-259
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• 1999

Small round structured viruses (SRSV) are the major ethological agents which can cause outbreaks of non-bacterial gastroenteritis or food poisoning both in children and adults. The classification of family Caliciviridae to which SRSV belong, is based on the genome encoding three open reading frames. The rotavirus is another major pathogen which causes diarrhea in young children. We examined stool specimens obtained from diarrheal patients in Wonju from which bacterial pathogens were not found. To detect causative viruses from stool specimens of patients, reverse transcription (RT)-polymerase chain reaction (PCR) or nested PCR using rotavirus or SRSV specific primers was performed. In this study, RT-nested PCR procedure which can amplify a 330 bp fragment derived from RNA dependent RNA polymerase (RDRP) region within ORF1 was applied for the detection of SRSV. For the detection of rotaviruses, a 877 bp fragment from the VP4 region of rotavirus genome was amplified. As a result, rotavirus was not detected while SRSV sequences were detected from one out of five specimens. The nucleotide and amino acid sequences of the Wonju isolate were compared with other 6 Korean isolates which have been isolated and sequenced in our laboratory. Sequence analysis revealed that the Wonju isolate was rather distinct from other Korean isolates: the Wonju isolate was closer to genogroup I of SRSV while other 6 Korean isolates belonged to genogroup II.

• Journal of The Korean Society of Integrative Medicine
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• v.3 no.1
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• pp.91-103
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• 2015

Purpose: The purpose of this study was to investigate the effects of home exercise program and exercise program of round shoulder adjustments on the level of trapezius muscle activity and attention capacity for middle school students. Method: The participants in this study were composed of 21 middle school students. We made the students lie on the floor in prone position, then measured the height of their acromion from the floor. We chose participants for our study whose measurement values were over 2.5cm. We divided them into two groups, one is for the experimental group, and the other is for the control group. The experimental group exercised three days a week for 6 weeks, including home training, and the control group didn't exercise. We used EMG to measure the trapezius muscle's activity and used a Stroop test for the measurement of the students' attention capacity. Results: The results of our study are as follows. There was no significant difference between the experimental group and the control group. However, there was a significant difference within the experimental group when comparing pre and post training results for Trapezius muscle activity and attention capacity. Conclusion: We found that correcting round shoulder symptom increases the Trapezius muscle activity and students' attention capacity. Future experiments should investigate with systemical management. Also, we need to increase the frequency of the exercise and participants.

• Restorative Dentistry and Endodontics
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• v.22 no.2
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• pp.546-559
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• 1997

The purposes of this study were to evaluate the efficiency of cavity preparation and to determine the incidence of tooth crack when root-end retrograde cavity preparation was done with ultrasonics. 91 distobuccal root-ends of extracted human maxillary first molars were cut by 3 mm perpendicularly to the long axis of tooth using a slow speed diamond saw, retrocavities were prepared using a slow-speed no. 2 round bur as controls, and stainless steel ultrasonic tips of power settings of 1 through 10 as experimentals. Time consumed and the number of strokes used for the cavity preparation were measured and evaluated, and the incidence of tooth cracks was observed under a stereomicroscope. The results were as follows : For the retrograde cavity preparation, time and number of strokes used were decreased as the ultrasonic power setting increased (p<0.001). High power setting of ultrasonics induced significantly more tooth cracks than did the slow-speed bur or low- and medium power setting of ultrasonics (p<0.05). Teeth with previous crack induced significantly more tooth cracks than those without previous one when high power setting of ultrasonics were used for the retrograde cavity preparation (p<0.001). Teeth with initial apical canal size of no. 10 induced significantly more crack than did those with size of no. 15 when low power setting of ultrasonics were used for the retrograde cavity preparation (p<0.05).

• Korea journal of population studies
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• v.19 no.1
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• pp.73-92
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• 1996

There are basically three approaches of surveys on the economically active population, namely Labor Force Approach (or Current Status Approach), Usual Status Approach, and Gainful Worker Approach. The selection of an approach among these approaches to be applied to a survey or population census should take into considerations the purpose and background of the survey or the census and the socio-economic situation of a country. In the Korean Population and Housing Census series which have been taken almost every five years since its first round in 1925, a sample survey on the economically active population has been adopted since the 1960 round of census. Even if the labor force approach continued to be applied to the censns prior to 1980, the approach has been different from one round to another in recent rounds. It may be suggested that the labor force approach continue to be adopted for the Korean Population and Housing Census for the following reasons: 1) the proportion of seasonal workers to the total workers is very small, 2) the proportion of population whose type of activity for a specific duration is different from that for one year is small, 3) the approach for the census should be the same as that for a variety of sample surveys on the economically active population which adopt the labor force approach, since the census functions as a population as well as a bench mark for those sample surveys, 4) an application of labor force approach will facilitate international comparisons since most of countries that conduct a population census adopt this approach, 5) the labor force approach can improve the reliability of results, thanks to its short reference period, etc.

• 대한공업교육학회지
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• v.33 no.1
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• pp.1-22
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• 2008

The purpose of this research is to clarify the elements of the function of the role of industrial high schools that its experts perceived. The content of this research is verify the function element required for the performance of the role of specialized education through content validity ratio(CVR). This research adopted the method of literature research and Delphi method, which is to collect and come to an agreement of the opinions of the 26 research panels. The first round is constructed by the semi-constructed questionnaire for the analysis of the opinions of the panels by inductive method. The second round is to categorize the result of the first one into 7 domains, and asked each category by Likert's 5 scale checklists, and statistically analyzed mean, medium, standard deviation, and quartile. The third round is to statistically analyze Mean, standard deviation, medium, and validity ratio(CVR) to reassure the opinions of the panels on the basis of the result of the first one. The categorized contents of the function required for the performance of the specialized education in this research is 'in-service visit and in-service training', 'licence acquiring education', 'employment counseling and job employment information', 'custom-made education connected with industry', 'career education' and 'enhancement of basic career competency'. The panels are divided into professors, teachers, professionals, and policy administrators, and they verified the validity rate of the function role and priority of emphasis. The result showed that the tendency of the education is converting from physical function-centered education to education of emotional attitude and competence of thought.