• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.3
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• pp.499-506
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• 1999

The odontoma is relatively a common benign odontogenic tumor and caused by overgrowth of odontogenic tissues. The recent classification by World Health Organization divides odontoma into 2 groups such as compound odontoma and complex odontoma. Compound odontoma comprises dental tissues, resembling the morphology of a tooth and has predilection for the anterior maxilla. In contrast, complex odontoma has unorganized mass, not resembling the normal tooth and has predilection for the posterior mandible. The etiology of odontoma is unknown and almost asymptomatic. So, it usually is found in routine radiographic examination, and most common presenting symptom is impacted or unerupted permanent teeth and retained primary teeth. It can occurs almost anywhere in jaws. It is desirable that odontoma should be removed by surgical enucleation including follicle and surrounding soft tissues. Considering the age and behavioral cooperation of patient, the development of permanent dentition, the location of odontoma in jaw, the need for the concomitant operative dentistry, operation is performed in outpatient department with/without sedation or under general anesthesia with endotracheal intubation. In this case report, 2 patients with compound odontoma were treated by surgical enucleation including follicle and surrounding soft tissues. One patient, about 5 years old, was treated under general anesthesia and concomitant operative dentistry was performed. The other patient, about 11 years old, was treated under local anesthesia in outpatient department. In 2 cases, after 4 months, surgical defects were filled with new bone and normalization of eruption path of impacted permanent teeth was observed.

• Journal of Periodontal and Implant Science
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• v.26 no.3
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• pp.605-624
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• 1996

Various bonegraft materials and the technique of guided tissue regeneration have been used to regenerate lost periodontal tissue. Calcium sulfate has been known as a bone graft material because of good biocompatibility, rapid resorption and effective osteoinduction. It has been known that calcium sulfate works as a binder to stabilize the defect when it is used with synthetic graft materials. The effects on the regeneration of pericxiontal tissue were studied in dogs after grafting 3-wall intrabony defects with calcium carbonate and calcium sulfate and covering with calcium sulfate barrier. The 3-wall intrabony defectstdmm width, 4mm depth, 4mm length) were created in anterior area and treated with flap operation alone(contol group), with porous resorbable calcium carbonate graft alonetexperirnental group 1), with calcium sulfate graft alonetexperimental group 2) and with composite graft of 80% calcium carbonate and 20% calcium sulfate with calcium sulfate barriertexperimental group 3). Healing responses were histologically observed after 8 weeks and the results were as follows: 1. The alveolar bone formation was $0.59{\pm}0.19mm$ in the control group, $1.80{\pm}0.25mm$ in experimental group 1, $1.61{\pm}0.21mm$ in experimental group 2 and $1.94{\pm}0.11mm$ in experimental group 3 with statistically significant differences between control group and all experimental groups(P<0.05). There were statistically significant differences between experimental group 1 and group 2 (P<0.05). 2. The new cementum formation was $0.48{\pm}0.19mm$ in the control group. $1.72{\pm}0.26mm$ in experimental group 1, $1.43{\pm}0.17mm$ in experimental group 2, $1.89{\pm}0.15mm$ in experimental group 3 with statiscally significant differences between control group and all experimental groups (p<0.05). There were statistically significant differences between experimental group 1 and group 2, and between experimental group 2 and group 3(P<0.05). 3. The length of junctional epithelium was $1.61{\pm}0.20mm$ in the contol group, $0.95{\pm}0.06mm$ in experimental group 1, $1.34{\pm}0.16mm$ in experimental group 2, $1.08{\pm}0.11mm$ in experimental group 3 with statiscally significant differences between control group and experimental group 1. and btween control group and experimental group 3(p<0.05). There were statistically significant differences between experimental group 1 ,and group 2, and between experimental group 2 and group 3(P<0.05). 4. The connective tissue adhesion was $1.67{\pm}O.20mm$ in the control group, $1.33{\pm}0.24mm$ in experimental group 1. $1.23{\pm}0.16mm$ in experimental group 2, $1.08{\pm}0.14mm$ in experimental group 3 with statistically significant differences between control group and all experimental groups(p<0.05). There were nostatistically significant differences between all experimental groups. As a result, epithelial migration was not prevented when calcium sulfate was used alone, but new bone and cementum formation were enhanced. Epithelial migration was prevented and new bone and cementum formation were also enhanced when calcium carbonate was used alone and when both calcium carbonate and calcium sulfate were used.

• The Journal of the Korean bone and joint tumor society
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• v.19 no.2
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• pp.56-63
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• 2013

Purpose: This study was performed to evaluate the efficiency of demineralized bone matrix (DBM, Genesis$^{(R)}$) used for bone defect after operative traetment of benign bone tumors by clinical and radiological methods. Materials and Methods: DBM was used to treat bone defect after operative treatment of benign tumor from February 2012 to May 2013. Total 25 benign bone tumor cases (15 males, and 10 females) with mean age of 30.3 were studied. The diagnoses were solitary bone cyst in 9 cases, non ossifying fibroma in 5, fibrous dysplasia in 5, aneurysmal bone cyst in 3 and enchondroma in 3. In categorization by location of tumor, there were 5 cases of distal femur, 4 of proximal tibia, 3 of proximal femur, 3 of proximal humerus, 3 of phalanx, 2 of distal radius, 2 of hip bone, 2 of calcaneus, and 1 of scapula. Autogenous bone was used with DBM in 6 cases, and only DBM used in 19 cases. Mean periods of follow up were 8.7 months (range: 6 to 14 months). Amount of graft resorption and bone formation was observed with compare of post operation radiograph and the difference was shown by percentage. Resorption level was measured by DBM level which could be observed from simple x-ray, and bone formation level by bone trabecular formation level at impaired site. Results: Twenty three cases of total 25 cases showed bone union. In the 23 cases, more than 98% DBM resorption was observed after mean 4.3 months, and more than 98% bone formation was observed after mean 6.9 months. Lesser bone defect sizes showed faster bone formation and it was statistically significant (p=0.036). But other comparative studies on other factors such as, sex, age of patients and combination of autogenous bone were no statistically significant differences in graft resorption and bone formation. And there was no significant complication in periods of follow-up. Conclusion: Demineralized Bone Matrix (Genesis$^{(R)}$) is thought to be useful treatment for bone defect after operative treatment of benign bone tumor, however longer follow-up periods appears to be needed.

• Journal of radiological science and technology
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• v.31 no.2
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• pp.109-114
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• 2008

There is a standard shoulder oblique method (Grashey method) available to view the shoulder joint. This method projects AP view of the shoulder joint so that the Humerus head's subuxation or joint degeneration can be easily visualized. However, in this view, the patients, with supine or sitting or erect position, have to keep their body obliquely. Whereas, the patients who are not well or operated, usually feel very uncomfortable to keep their body in this position and hence, we need other persons' help and much efforts will be needed to get the good quality shoulder joint view. Therefore, we thought of examining a method which shows the joint well by angling the tube to Medio-Lateral direction and without keeping the patients' one side upward in supine position. For this study, total 15 subjects with no history of neurological or psychiatric illness, were recruited for examinations. They consisted of 9 males and 6 females. Statistic group analysis was performed with ANOVA test. Scores of the evaluation of the experts were $1.10{\pm}0.54$ at $25^{\circ}$, $2.50{\pm}0.50$ at 30^{\circ}$, $2.85{\pm}0.36$ at $35^{\circ}$ and $2.33{\pm}0.47$ at $40^{\circ}$, respectively, and they were significant(p<0.05, Table 1). Joint space of the Humerus head and Scapula were well distinguished at $35^{\circ}$, $30^{\circ}$ and $40^{\circ}$ with the almost same score. However, the degree of distortion at $40^{\circ}$ was more severe than that at $30^{\circ}$. Ultimately, $30-35^{\circ}$ views were shown to yield good quality shoulder oblique images. In conclusion, this method may be very useful for the patients who are uncomfortable and for the emergency patients. In order to get similar or comparable view, the same X-tube angle is recommended to be used before and after the operation. Therefore, we hope that this new angled method seems to be efficient.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.12
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• pp.1280-1286
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• 2006

Three different virgin activated carbons made of each coal(Calgon), coconut(Samchully) and wood(Picabiol) based activated carbon(AC) were tested for an adsorption performance of 1,4-dioxane in a continuous adsorption column. Breakthrough behavior was Investigated that the breakthrough points of coal, coconut and wood based AC were observed as 3600 bed volumn(BV), 1440 BV and 144 BV respectively. Adsorption capacity(X/M) of coal, coconut and wood based AC was observed. The reported results of adsorption capacity showed that coal based AC was highest(578.9 ${\mu}g/g$), coconut based AC was intermediate(142.3 ${\mu}g/g$) and wood based AC was lowest(7.4 ${\mu}g/g$) due to increasing specific surface area. Moreover, carbon usage rates(CURs) for coal, coconut and wood based AC had been shown as 0.48 g/day, 1.41 g/day and 6.9 g/day respectively. The constant characteristic of the system, k of coal based AC was found to be 91.5 and k of coconut based AC was found to be 17.9. Removal efficiencies of 1,4-dioxane with different ozonation dosages(2 and 5 mg/L) for 20 min ozonation had been shown 38% and 87% respectively. There was no observation for biological removal of 1.4-dioxane by attached micro-organisms when used(3.1 years and over 5 years) biological activated carbon(BAC) without pretreatment of oxidation were employed. When a combination of ozonation(2 mg/L and 5 mg/L) and BAC process for $10{\sim}30$ min was applied, removal efficiency for 1,4-dioxine increased only $2{\sim}6%$ compared to only applying ozonation. Therefore removal efficiency of BAC process prior to using oxidation was proven to negligible. Consequently, the results presented in this paper provide a better insight into the adsorption performance of 1,4-dioxane. This observation suggests that using virgin activated carbon made of coal is the best selection for removal of 1,4-dioxane in the water treatment for an advanced treatment. It is clear from this research that longer EBCT for ozonation or higher ozone concentration are more effective operation methods for removal of 1,4-dioxane than longer EBCT in the BAC process.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.6
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• pp.658-665
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• 2013

In this study, we measured particulate matter(PM) which emerged as the hot issue from the International Maritime Organization(IMO) and the exhaust emission using HANBADA, the training ship of Korea Maritime University. In particular, the PM was obtained with TEM grid. PM structure was observed by electron microscopy. And exhaust gases such as NOx, $CO_2$, and CO were measured using the combustion gas analyzer(PG-250A, HORIBA). The results of this study are as follows. 1) When the ship departed from the port, the maximum difference in PM emissions were up to 30 % due to the Bunker Change. 2) Under the steady navigation, emission of PM was $1.34mg/m^3$ when Bunker-A is changing L.R.F.O(3 %). And, at the fixed L.R.F.O (3 %), emission of PM was $1.19mg/m^3$. When the main engine RPM increased up to 20 % with fixed L.R.F.O(3 %), emission of PM was $1.40mg/m^3$. When we changed to low quality oil(L.R.F.O(3 %)), CO concentration from main engine increased about 16 %. On the other hand, when the main engine RPM is rising up to 20 %, CO concentration is increased more than 152 percent. These results imply that the changes of RPM is a dominant factor in exhaust emission although fuel oil type is an important factor. 3) The diameter of PM obtained with TEM grid is about $4{\sim}10{\mu}m$ and its structure shows porous aggregate.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.721-728
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• 2008

DBPs(Disinfection By-Products) are most formed through the reactions between chlorine and NOM(Natural Organic Matter) in water treatment. In this study, occurrence of DBPs including THMs(Trihalomethanes) is evaluated. Also, influencing factors by the seasons and raw water quality were investigated for correlation among them and the characteristics of THMs formation by prechlorination process. This study investigated the operation condition for THMs removal depending on raw water quality. Water treatment plant from intake station to gauging well flows for about 10 hours in Y Water Supply Office. It is limited to control of THMs formation because of excessive reaction time between chlorine and THMs precursors in the intake station. Therefore, as multi-points prechlorination from intake station to gauging well, THMs formation was decreased in the water treatment, and it was willing to prevent overdosage of chlorine. The concentration of THMs was 0.021 mg/L in the summer, 0.015 mg/L in the winter, respectively. Also, THMs formation showed that 0.013 mg/L in the water of gauging well after prechlorination, 0.014 mg/L in the flocculation/sedimentation/filtration, 0.016 mg/L in the water after postchlorination, respectively. THMFP(Trihalomethane Formation Potential) removed 42.7% and 50% through the flocculation/sedimentation and filtration, respectively, and it is similar TOC removal efficiency. In this study, multi-points prechlorination from intake station to gauging well decreases in contact time and concencrations of NOM and chlorine. Also, it decreases in THMs and amount of chlorine uesd. In the result of multi-points prechlorination in the summer, the concentration of THMs was 0.013mg/L in the treated water. In view of these facts, THMs formation can be decreased approximately 50%.

• Journal of Korean Orthopaedic Sports Medicine
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• v.4 no.1
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• pp.18-28
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• 2005

Purpose: The purpose of this study is to evaluate the clinical, radiological and histopathological results after microfracture surgery for degenerative arthritis of the knee. Materials and Methods: From Oct. 1997 to Dec. 1998, 48 knees in 46 patients were treated by microfracture technique. Their mean age at the time of operation was 56 years(range, 40-75 years) and mean period of follow-up study was one year(range, 7-20 months). For 24 knees in 22 patients, 'second-look' arthroscopies and biopsies were performed at 6 months following microfracture. At the last follow up clinical results were evaluated with Baumgaertner's scale. The specimens of 24 cases were stained with H-E, Safranin-O, and Masson's trichrome. Eighteen of 24 cases were stained immunohistochemically and the Western blotting test was performed on 12 cases for type II collagen. We analyzed the relationship of the Western blotting for type II collagen with clinical score, preoperative varus deformity, joint space widening in radiological result, extent of repaired articular cartilage in '2nd-look' arthroscopic findings, patient's age and weight. Results: Clinical results were excellent in 90% and good in 10%. Among the 24 knees, more than 80% of areas of chondral defect were covered with regenerated cartilage in 21 knees Histologically, the repaired tissue appears to be a hybrid of hyaline cartilage and fibrocartilage. Repaired cartilage contains variable amounts of type II collagen with immunohistochemical staining. The results of the Western blotting test were similar. The amounts of type II collagen formation had positive correlation with the extent of repaired cartilage and preoperative varus deformity. Conclusion: 'Second-look' showed that the chondral defect areas were covered with newly grown grayish white tissue. Articular cartilage repair was confirmed with histological and immunohisto-chemical study qualitatively, and the amount of type II collagen was calculated with the Western blotting test quantitatively. The exact nature and fate of repaired cartilagenous tissues need further long term follow-up study. The results of this study provide the rationale to select osteoarthritic patients indicated for microfracture surgery.

• Journal of Distribution Research
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• v.17 no.5
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• pp.129-146
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• 2012

Recently, Korea became the 7th country in the world which has got into the 20-50 clubs that means the population is 50 million and per capital income is $20,000. From the view point of the retail industry, it suggests that Korea should have its own self-sufficient market by itself. With abundant labor and increased disposable income, it made the consumer's needs change. Responding to the change, retail and F&B oriented retail malls are now starting to add culture, art and entertainment facilities in the configurations. Such complexity and variety of the shopping malls became trendy and many shopping complexes are scheduled to open in the near future across the country. Due to above reasons, it became the common trend to develop shopping complex all over the cities now. However, the history of the shopping mall in Korea is much shorter than developed countries such as America and Japan. Thereby, a lot of problems, trial and error have occurred in the process of developing and operating them. If development of shopping complex failed, it would return lots of damages to the stakeholder. Therefore, the corporations should develop the mall properly and government might support positively. In this study, we would like to propose on how all the mall should be developed and well managed and what are the ways for the vitalizing factors of the shopping complex after benchmarking other shopping mall cases. Through the case study, we realized that the most crucial factors for vitalizing shopping complex were interior design, merchandising and how well they operate the mall. In case of the failed shopping mall, developers sell each store to individual proprietors and never take care of them after they get the profit, which make it hard to have integrated marketing strategies. That causes the overall slump of the mall. Corporations developing the mall should operate it as well, so that it could be possible to make the mall consistently well managed and promoted. There is a certificate for the shopping mall expert in The States and Japan. However, we do not have this kind of certificate. In fact, if we judge the capability of a person who is involved in the shopping mall industry, we usually measure how many years they stick to the same industries and that is not equally the same as their competence. Therefore it is necessary to organize "Shopping Mall Associate" and introduce shopping mall license for the mall expert. Due to retail trends, we can easily see a lot of shopping facilities all over the cities but not every mall is able to be successful. We think it's essential that the government should certify the malls which are qualified for the design, merchandising and proficiency of the operation. For the qualified mall, the government could confer a benefit on the company such as reducing corporation taxes. In multi-complex shopping mall it is possible to make convenient for customers. However, if a mall failed to succeed, it would be disaster. To build a shopping complex, developers should invest huge money even take out loan so that many people would be connected to the project, which may affect their whole financial conditions. In addition, only qualified corporation should develop and operate shopping complex and the government must support and aid the developers in order to make a better shopping environment in which customers might be happy during their shopping experience.

• The Journal of Industrial Distribution & Business
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• v.2 no.2
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• pp.25-38
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• 2011

After the financial crisis, what has been the rapidly growth of large supermarkets, stores, and restaurants linked to concerns that have already reached saturation point, but the new opening large supermarkets is expected to continue into the future. The major supermarkets are continue to grow outward but growth slowed. And that is expected to continue differentiation of the product, acceptance the customer needs, acquiring high margin of sales products. Then the ongoing development of PB brand is to be positioned effective marketing strategy for overcoming the period of slow growth. In addition, big three local supermarkets continue to launch a clothing PB brand, expansion and operation strategy for the situation and based on this study and the success of the domestic large-Mart's PB and PB identifying problem and the need for differentiation and profit for the successful strategy is to discuss in this study. This research looks at the concept of major market's private brand, the strategy, the success example and the prospects, and views the globally rapid-growing private brands, not only having the limited role of distributing the products as retailers, but also having a control of the distribution channel as a manufacturing company. World's major advanced distribution companies, to differentiate their companies' products and increase the profitability, are putting a lot of efforts into private brand products, and there are many good examples that are globalizing, externally expanding, and creating high financial results. In this research, we presented three major domestic discount stores as examples to show that there is a need for a differentiated private brand management strategy in the saturated discount store industry in Korea. Also, we aim to provide a new product strategy for the future that has been saturated with discount stores to the limit, by providing suggestions that private brand products can be used as weapons with the strongest competiveness in the retail industry through pursuing store differentiations from thorough market analysis and product researches, meeting the customers' needs, and obtaining high margins. PB products, particularly clothing design, a thorough market analysis and product development trends and customer needs to reflect the acquisition of High margin differentiated powerful products and sustainable growth through the stores, large supermarkets, congested, a new breakthrough that can give a good opportunity to provide implications discount stores, new product strategy based on ways to limit proposed. This study discount the major three companies studied, the less strain is a generalization. In the future, domestic and local discount store brand PB, SPA brand that the multinational comparative analysis of the value of the PB expansion strategy centered on clothing, additional studies will be needed.