• The Journal of Korean Academy of Prosthodontics
• /
• v.43 no.2
• /
• pp.232-247
• /
• 2005

Purpose. The purposes of this investigation were to discover the possibility of clinical application in the areas of dental implants and bone grafts by investigating the bone formation histologically around specimen which was depending on the intensity of magnetic field of neodymium magnet inside of the specimens. Material and method. 1. Measurement of magnetic intensity - placed the magnet inside of the specimen, and measured the intensity of magnetic field around the 1st thread and 3rd thread of specimen 20 times by using a Gaussmeter(Kanetec Co., Japan). 2. Surgical Procedure - Male rabbit was anesthetised by constant amount of Ketamine (0.25ml/kg) and Rompun (0.25ml/kg). After incising the flat part of tibia, and planted the specimens of titanium implant, control group was stitched without magnet, while experimental groups were placed a magnedisc 500(Aichi Steel Co., Japan) or magnedisc 800(Aichi Steel Co., Japan) into it, fixed by pattern resin and stitched. 3. Management after the surgery - In order to prevent it from the infection of bacteria and for antiinflammation, Gentamycin and Ketopro were injected during 1 week from operation day, and dressed with potadine. 4. Preparation of histomorphometric analysis - At 2, 4 and 8 weeks after the surgery, the animals were sacrificed by excessed Ketamine, and then, specimens were obtained including the operated part and some parts of tibia, and fixed it to 10% of PBS buffer solution. After embedding specimens in Technovit 1200 and B.P solution, made a H-E stain. Samples width was 75$\mu$m . In histological findings through the optical microscope and using Kappa image base program(Olympus Co. Japan), the bone contact ratio and bone area ratio of each parts of specimens were measured and analyzed. 5. Statistical analysis - Statistical analysis was accomplished with Mann Whitney U-test. Results and conclusion. 1. In histomorphometric findings, increased new bone formation was shown in both control & experimental groups through the experiment performed for 2, 4 & 8 weeks. After 4 weeks, more osteoblasts and osteoclasts with significant bone remodeling were shown in experimental groups. 2. In histomorphometric analysis, the bone contact ratios were 38.5% for experimental group 1, 29.5% for experimental group 2 and 11.9% for control group. Experimental groups were higher than control group(p<0.05) (Fig. 6, Table IV). The bone area ratios were 60.9% for experimental group 2, 46.4% for experimental group 1 and 36.0% for control group. There was no significantly statistical difference between experimental groups and control group(p<0.05) (Fig. 8, Table VII) 3. In comparision of the bone contact ratios at each measurement sites according to magnetic intensity, experimental group 2(5.6mT) was higher than control group at the 1st thread (p<0.05) and experimental group 1 (1.8mT) was higher than control group at the 3rd thread(p<0.05) (Fig. 7, Table V, VI). 4. In comparision of the bone area ratios at each measurement sites according to magnetic intensity, experimental group 2(5.6mT) was higher than control group and experimental group 1 (4.0mT) at the 1st thread(p<0.1) and experimental group 2(4.4mT) was higher than experimental group 1 (1.8mT) at the 3rd thread(p<0.1) (Fig. 9, Table IX, X). Experiment group 2 was largest, followed by experiment group l and control group at the 3rd thread of implant. There was a significant difference at the 1st thread of control group & experiment group 2, and at 1st thread & 3rd thread of experiment group 1 & 2, and not at control group experiment group 1.(p<0.1)

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.2
• /
• pp.267-276
• /
• 2005

This study was carried out to investigate the effects of Kimchi ingredients, garlic, ginger, green onion and fermented fish sauces, on the Kimchi characteristics during fermentation. The experiment design of this study was the central composite design and response surfaces methodology. Garlic (X$_1$) of 0∼2%, ginger (X$_2$) of 0∼1.4%, green onion (X$_3$) of 0∼4% and fermented fish sauces (shrimp, X$_4$ and anchovy, X$_{5}$) of 0∼2% per salted Chinese cabbage of 100 g put in independent variables, respectively. The result of response surface regression analysis, independent variables of various ingredients and dependent variables, correlation coefficient ($R^2$) showed very difference value according to added ingredients. In the Kimchi samples fixed independent variables of garlic (X$_1$)-ginger (X$_2$), generally, it showed high correlation value more than samples fixed other independent variables of garlic (X$_1$)-green onion (X$_3$) and ginger (X$_2$)-green onion (X$_3$) over the fermentation period. And the correlation coefficient ($R^2$) of fermented fish sauces (shrimp of X$_4$, anchovy of X$_{5}$) showed value over 0.8 in the its characteristics of Kimchi samples except for textural properties of sensory evaluation. In the graph pattern of fermented fish sauces using response surfaces methodology, it showed a little increasing value of titratable acidity, lactic acid bacteria and 'a' of redness, 'b' of yellowish according to increasing addition fermented fish sauces. In the total acceptability of sensory evaluation, it showed high value according to increasing fermented fish sauce at the initial fermentation period of Kimchi. But it showed high value Kimchi sample added content of 1.0% fermented fish sauce in the middle (appropriate fermentation) and last (excessive) fermentation period.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.37 no.1
• /
• pp.117-123
• /
• 2010

Tooth eruption is the movement of the tooth from the developing place in the alveolar bone to the functional position in the oral cavity. The permanent incisors originate from the dental lamina on the lingual side of preceding deciduous tooth and erupt to the level of the occlusion through the well developed gubernacular cord. Ectopic eruption is a developmental disturbance in the eruption pattern of the permanent dentition. Most of the ectopically erupted lower incisor has been found in lingual side. The ectopically erupted tooth could be repositioned by orthodontic force in the early mixed dentition, which could help preventing the problems of loss of space and the lingual tilting of the lower anterior teeth. An eight-year-old girl visited the department of pediatric dentistry, Yonsei Dental University Hospital, for the evaluation and the treatment of the lower right lateral incisor, which was horizontally erupted in the lingual side, parallel to the mouth floor. Her tongue was placed on the labial side of that tooth. There was no previous dental history of dental caries or trauma on the pre-occupied primary incisor. Clinical and radiographic examinations including the computed tomography(CT), showed no evidence of dilacerations on root. Therefore, we decided to start active orthodontic traction of the lower right lateral incisor. We designed the fixed type of buccal arch wire and the lip bumper with hook for the traction. Button was attached to the lingual side of the ectopically positioned tooth. Elastic was used between the appliance and the button on that tooth. After the tooth become upright over the tongue level, appliance was change to the removable type and periodic check-up with occlusal guidance was followed to monitor the position of the tooth. In this case using the fixed appliance with modified form of lip bumper and hook embedded in acrylic part instead of extraction was very efficient up-righting the ectopically erupted tooth toward the occlusal plane.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.34 no.3
• /
• pp.388-397
• /
• 2008

The present study was performed to evaluate the function of the mandible according to the pattern of fracture and treatment methods of condylar fractures of the mandible and help operators in making a treatment plan. Sixty patients (average follow-up period was $7.8{\pm}9.4$ months) who were treated for condylar fracture from June, 2002 to May, 2006 at the Department of Oral and Maxillofacial surgery, Chonnam National University Hospital were reviewed. The common causes of the condylar fracture were traffic accident and fall-down (35.0%). In concomitant injuries, laceration was 46.7% and the fracture of the mandibular symphysis was highest incidence (60.0%). The common site of the fracture was the condylar head (47.8%), followed by subcondyle (36.2%) and condylar neck (15.9%). Under 15 years old patients, the closed reduction was performed in 87.5% out of the patients. All of the condylar fragments were fixed to the mandible with titanium miniplates in cases of open reduction. The mean period of intermaxillary fixation (IMF) was $14.2{\pm}6.5$ days in closed reduction and $10.0{\pm}4.2$ days in open reduction. The old patient with bilateral condylar head fractures, who were treated by closed reduction with IMF for 3 weeks, showed the limitation of mandibular movements. But, there was no significant different results between open reduction and closed reduction with the respect of the Helkimo's mandibular mobility index and clinical dysfunction index (DI). Complications, such as fibrous ankylosis and resorption of the mandibular condyle, were not observed in all patients. These results suggest that the good results can be obtained by closed reduction with proper IMF periods and functional exercise in most condylar fractures of the mandible except severely displaced extracapsular fractures.

• Korean Journal of Poultry Science
• /
• v.20 no.2
• /
• pp.107-114
• /
• 1993

The structure change in the broiler industry of Korea has been taking place very rapidly toward the direction of integrated production and marketing system. During the course of the evolution into the integrated structure, however, a number of small business entities, uncountable nationally but a minimum of a dozen, that previously engaged in the supply of production factors or live bird transaction also tended to get involved in the new system as a disguised or pseudo-integrator, having brought a lot of problems not only to the farmers but also to the development of integrated structure. The pseudo-integrator is generally characterized by limited functions in such a way of supplying chicks and feeds to and collecting grown birds from farmers under the contract at a fixed farmer's payment in practically the same pattern as a partial or quasi-integration, which intends to act as if an integrator in a stratagem to simply enjoy a margin simply from selling supplies and buying products for a certain period of time. The grower making a contract with appears to be a farmer who used to be an Independent and speculating but not able to join in the normal system of evolving integration. The problems of a pseudo-integrator center on the financial loss to a contract farmer, because the falsified integrator has to become easily bankrupt and run away when the price of live broiler continually stays below the cost of production, even though he is able to make a tremendous profit otherwise which is the real purpose of the operation for. It is true that the volatile market, fluctuating the price up more than doubled in a month and down to a half in a few weeks, makes the pseudo-integrator find the room for such a fraudulence. In addition, its activity also adversely affect the evolution of the integration due to rather negative image on structure change in general. It is recommended that the farmers need to better understand the real picture of the integrated system so as not to be swindled by a disguised, small scale agribusiness agent. By the same token, it is also equally required to have the whole industry integrated completely as early as possible. The Joint effort to get rid of pseudo-integrators' problems shall be put for the industry development moving toward the integration. No doubt a pseudo-integrator must be a temporary player for chance emerging during the course of structure change into the integrated, though.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.39
• /
• pp.143-175
• /
• 2008

The documentary letter of credit is the most preferred and frequently used method in International Payment System in Korea, as it has less possibility of occurring credit risks in export than any other payment system. That's because the exporter can get payment from the issuing bank(confirming bank) by delivering the goods and presenting documents following the required procedure under the letter of credit, as the payment is affirmed by the issuing bank(including the confirming bank in case of the confirmed letter of credit) regardless of the buyer's payment. However, the pattern of payment methods used in international trade of Korea is changing dramatically like the importance of the credit is decreasing continuously among the payment methods while the remittance is increasing. The increase of remittance has a positive aspect that International Payment System are changing into those of advanced countries, but the decrease of the credit also has a negative aspect that the exporter might have a greater credit risks. Therefore, we need a systematic device to deal with this. Exporters in Korea usually have used the export credit insurance to deal with the credit risks However, the export credit insurance also have a limitation as the policy finance due to the limitation based on the credit status of the business and the limitation of acceptance from the lack of financial resources of the government, etc. Korea, which is the 11th export power in the world, has a basic limitation to deal with the credit risks by depending on the export credit insurance only. So, in this thesis, I have studied on the international factoring, forfaiting, which are advanced export finances and widely used in advanced countries, as substitutes to deal with the credit risks. the international factoring is an trade financing in which a factor offers full services such as credit cover, offering prepayment, collection, account receivables, management, etc, instead of the exporter on the account receivables occurred by the exporter's delivering goods to the importer. This international factoring has a high possibility of using as a means to deal with the credit risks, because it offers prepayment without recourse. the forfaiting is another export financing in which a forfaiter purchases the draft, the promissory note and other negotiable instruments issued from the international trade, with fixed interest rate without recourse from the exporter or previous holder. By using this method, they can avoid foreign exchange risks, contingency risks as well as credit risks, as the conveyances like the promissory note, etc are issued with the note warranty so-called 'per aval' in business practice. These trade financing are good substitutes to deal with the credit risks in export, but they are not widely used in Korea. Though it can be explained with various reasons, the common reasons are the lack of understanding on the use of advanced export finance, the lack of experts to manage the advanced trade finance, the conservative way of thinking of domestic organizations related to trade financing, the lack of organizations supporting the trade financing, etc.

• Tuberculosis and Respiratory Diseases
• /
• v.71 no.6
• /
• pp.400-407
• /
• 2011

Background: There were a few studies which were conducted to know about the behavior of the chronic obstructive pulmonary diseases (COPD) patients. The aims of this study was to explore the behaviour of COPD patients, such as awareness and impact of disease, the pathway of visiting doctors, and the treatment pattern and preference. Methods: A face-to-face interview of 300 subjects with COPD was conducted. Results: The most concerned symptom which made the respondents to visit the hospital was 'breathlessness' (78%). Only 58% of them knew the exact diagnosis. Seventy-three percent of them visited the hospital 'once a month' or 'once every 2 month'. They have made 12.8 prescheduled visits to the hospital in the past 1 year. Unscheduled visits and hospital stay figured to two in the past year. Only 11% of respondents felt they were currently in good health. 'Severe' and 'very severe' COPD patients perceived their health to be in a worse condition than 'mild' and 'moderate' COPD patients. When conditions worsened, 42% of patients were hospitalized. The most common prescription treatment was a fixed combination of inhaled corticosteroids and long-acting ${\beta}2$ agonists (48%), followed by a long acting anticholinergics (38%). Conclusion: Over forty percent of the patients didn't know exactly about their condition. Most of them had a negative attitude toward their current health status. Doctors need to know more about COPD patients in terms of their attitude toward the disease, impact of the disease, interaction with healthcare professionals and treatment related problems.

• The Journal of Engineering Geology
• /
• v.3 no.2
• /
• pp.149-165
• /
• 1993

Nowadays, the field hydraulic test is still an only method to evaluate groundwater characteristics in subsurface. The results of hydraulic test are very important for the concept model of fracture hydrogeology as well as the geometric pattern of fractures. The hydraulic tests performed in Korea are generally analysed under such assumption as steady radial flow in homogeneous aquifer or along simple geometry of fractures. Also the transmissivity measured in a fixed interval length is equivalent to a sum of individual fracture transmissivities in test legth. The boundary effects of weH hydraulics and the geometry of flow paths are hardly obtained from the test results analysed by a steady flow method. To circumvent this problem, the flow dimensional analysis was attempted from the results of constant pressure injection test carried out in a fractured granite area. A comparison of the hydraulic conductivity values from the transient and steady analysis shows that the latter is about a factor of 2~3 higher than the former. However, it was possible to analyse a flow dimension of each test interval from flow rate variation with time. The upper part of the bedrock(<10m deep) indicates an open boundary and the flow dimension shows nearly steady states, while the lower part of the bedrock(>25m deep) is characterized as sublinear flow dimension with a dosed boundary. In one of the test sections(15m deep), the flow dimension was changed from linear flow to spherical flow. From the experience of this study, one of the immediate problems to be solved is to enhance the field testing equipments, i.e., an accurate flowmeter with autorecording and a pressure detecting device to be able to install in the test section.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.37 no.2
• /
• pp.1-14
• /
• 2000

The rosette-scan seeker, mounted on the infrared guided missile, is a device that tracks the target It can acquire the 2D image of the target by scanning a space about target in rosette pattern with a single detector Since the detected image is changed according to the position of the object in the field of view and the number of the object is not fixed, the unsupervised methods are employed in clustering it The conventional ISODATA method clusters the objects by using the distance between the seed points and pixels So, the clustering result varies in accordance with the shape of the object or the values of the merging and splitting parameters In this paper, we propose an Array Linkage Clustering Algorithm (ALCA) as a new clustering algorithm improving the conventional method The ALCA has no need for the initial seed points and the merging and splitting parameters since it clusters the object using the connectivity of the array number of the memory stored the pixel Therefore, the ALCA can cluster the object regardless of its shape With the clustering results using the conventional method and the proposed one, we confirm that our method is better than the conventional one in terms of the clustering performance We simulate the rosette scanning infrared seeker (RSIS) using the proposed ALCA as an infrared counter countermeasure The simulation results show that the RSIS using our method is better than the conventional one in terms of the tracking performance.

• Journal of Internet Computing and Services
• /
• v.17 no.1
• /
• pp.35-45
• /
• 2016

Melatonin hormone involved in human's circadian rhythm adjustment sensitively responds to light's specific short wavelength ratio. A shift worker's circadian rhythm disturbance and sleep disorder are caused by the existing lighting conditions, whose short wavelength ratio is fixed. The life pattern of a shift worker changes irregularly because of irregular working hours and the same lighting environment; thus, his/her concentration is reduced. For such a reason, negative effects ensue to the detriment of healthy everyday life, including a high risk of accidents or having unsound sleep after leaving work. A smartphone-based wavelength control LED lighting system that targets shift workers and that can easily measure and control lighting suitable for wake-sleep cycle, according to working hours and closing hours, is proposed in this paper. First, after the light characteristics of LED lighting that changes depending on light control ratio are measured through the color sensor installed on the smartphone and the externally-linked Mini-Spectrometer, they are stored in the database. Based on the stored optical characteristics data, the measurement module and light control module are implemented. Lighting is offered using a control ratio having the maximum rate of short wavelength in consideration of the target illuminance, classified according to work type by identifying working hours as time when waking is required for shift workers. After a shift work leaves work, the amount of lighting is varied, using a control ratio having a minimum short wavelength rate so that a shift worker can enter the sleep state naturally.