• Journal of Korean Society of Coastal and Ocean Engineers
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• v.15 no.2
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• pp.116-126
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• 2003

In this study, a method that leads to make a simple decision on important parameters in analysis of wave field in permeable rubble-mound, block-mound breakwater, such as penetration velocity of incident waves and resistance coefficient, is introduced. A model that could analyze wave field of permeable breakwater in harbor, by applying these methods and arbitrary transmission coefficient boundary condition to a time-dependent mild-slope equation, was introduced. The verification of the model was done by carrying out 2-D physical model test on permeable breakwater, measuring the change in water surface elevation, comparing the computation result with time series, and comparing the result gained from the 3-D physical model test on permeable block-mound breakwater in an field harbor with the computation result in terms of regional wave height ratio in a harbor.

• Journal of Navigation and Port Research
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• v.45 no.6
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• pp.325-332
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• 2021

As commercial and residential areas are actively developed around the coastal area with excellent scenery, installing coastal structures such as seawalls and breakwaters is continuously increasing to secure safe coastal regions. Additionally, the increase in the intensity of natural disasters due to climate change may cause higher incident waves than in the past, which may further aggravate the damage caused by wave overtopping. In this study, compared to the existing vertical seawall, we investigated the effect of wave overtopping reduction of a recurved seawall, which actively reflects the incoming waves, through the hydraulic model test. As a result of the hydraulic model experiment, it was confirmed that there was an effect of up to 92.4% of wave overtopping reduction in average compared to the vertical seawall and structures covered with armor blocks.

• International Area Studies Review
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• v.14 no.3
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• pp.3-33
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• 2010

While new evidence on international spillover effects has been widely discussed around the globe, the MENA (Middle East and North African) region has received little attention concerning international transmission of stock market movements. In this paper, we discuss international spillover effects between the major developed markets (US, Japan and Germany) and the emerging markets in the MENA region (Turkey and Egypt). While GARCH-type models have mainly been used to investigate international stock market spillovers in much of previous studies, we develop new testing strategies based on discrete wavelet decomposition. The basic finding is that price as well as volatility spillover effects exist from the developed stock markets to the MENA counterparts, although evidence for price spillover to the Egyptian market is rather weak. As for the interdependence of the major MENA stock markets, no spillover effects are found between these markets, while the two MENA markets are somewhat related with each other.

• Journal of the Korea Convergence Society
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• v.12 no.1
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• pp.163-170
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• 2021

Smart-textronics technology which enables functional textiles has recently been applied in various fields such as smart clothes, smart home and smart health care, and a variety of smart-textronics products have been developed. In this context, the smart-textronics product development process is proposed based on the systematic participatory design method in this paper. The proposed method consists of two phases: in-depth interviews and analyzing. In the phase of in-depth interviews, participants are asked to create journey maps that include activities, pain points and emotional status and to generate solution ideas with sketches and simple prototypes. In the analyzing phase, design researchers investigate the participants' journey maps, and create personas by identifying critical characteristics with the behavior pattern analysis. Then, each persona's needs are linked with value elements of the E3 value framework. Finally, pre-survey was conducted to identify smart-textronics market and a smart sofa design is proceeded as the case study to show the applicability of the proposed method.

• The Journal of the Korean bone and joint tumor society
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• v.6 no.1
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• pp.22-29
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• 2000

Purpose : The purpose of the current study was to report the results of curettage and en bloc excision as well as to introduce how to excise the nidus percutaneously with Halo-mill. Material and Methods : Twenty patients(14 men and 6 women) were evaluated, who had operative treatments after diagnosed as osteoid osteoma from March 1990 to January 1998. These patients ranged in age from 7 to 42 years(average: 20.8 years). Locations were 9 femurs, 6 tibias, 2 vertebras, 1 ulna, 1 maxilla and 1 skull. Nine femoral lesions included 5 proximal metaphysis, 2 neck and 2 diaphysis, while 5 tibial lesions included 3 diaphysis, 1 proximal metaphysis and 1 distal metaphysis. We used simple radiography, bone scan, CT and MRI for the accurate diagnosis and localization. As for surgical treatments, while excision and curettage had to need open-exposure of lesion, the percutaneous excision of nidus did not need openexposure : guided Halo-mill into K-wire inserted to nidus under image intensifier. Results : Simple radiography showed that 10 cases had typical nidus and others had only cortical sclerosis. Bone scan was performed at 14 cases and all had hot uptake except one case. We used CT in 10 cases and MRI in 4 cases as diagnostic methods, of which 1 case didn't reveal nidus at CT. Surgical treatment consisted of 6 curettages, 11 excisions, 2 percutaneous excisions with halo-mill and 1 total elbow arthroplasty. We used 7mm sized Halo-mill. During the follow-up period, all patient relieved symptoms and there were no recurrences. All had histologically typical findings except one which had hyperostosis without nidus. Conclusion : Complete removal of the nidus is the most important factor in the treatment. We could excise the nidus percutaneously in 2 cases with the minimal injury to surrounding soft tissues. If we could evaluate the precise location, size of nidus and percutaneous acccesibility, the percutaneous excision of nidus with Halo-mill could be an alternative method as a treatment of osteoid osteoma.

• The Journal of the Korean bone and joint tumor society
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• v.10 no.1
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• pp.13-21
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• 2004

Purpose: We analyzed the result of autologous bone marrow stromal cell transplantation with or without cancellous chip bone allograft for benign long bone lesions. Materials and methods: Since July 1996, eight benign bone lesions treated by curettage, cancellous chip bone allograft and bone marrow or marrow stromal cell transplantation were observed for resolution of clinical symptoms, new bone formation and consolidation. There were 6 males and 2 females. Average age was 24 (range 8 to 47) years old. Histologic diagnoses were 5 fibrous dysplasia, 2 simple bone cysts and one chondroblastoma and fibrous cortical defect each. Mean follow-up period was 16.3 (range 3 to 84) months. Results: In all four symptomatic patients, the pain was subsided in two weeks after surgery. New bone formation in the lesion was observed at 4 weeks, which incorporated into surrounding normal bone around 8 weeks. There were one pathologic fracture through the lesion at 3 weeks and one recurrence of simple bone cyst at 5 months postoperatively. Conclusion: Bone marrow or marrow stromal cell transplantation for bone defects from curettage of benign bone lesions, with or without cancellous chip bone allograft revealed rapid healing. Though it was the result of short-term follow up, it supports that bone marrow stromal cell transplantation will be very useful for the treatment of benign long bone cysts or other lesions. The complete curettage of inner cystic wall is important to prevent later recurrence, and the rigid internal fixation is also needed in selected high risk lesions of fracture.

• The Journal of the Korean bone and joint tumor society
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• v.17 no.2
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• pp.73-78
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• 2011

Purpose: This study was aimed to evaluate the result of inlay cortical strut bone grafts for large cysts or cavitary bone lesions in long bones. Materials and Methods: Seven patients with large cyst or cavitary bony lesions were managed with curettage, allogeneic inlay cortical strut and cancellous bone grafts. Additional plate and screw fixations were performed in 6 patients. There were three SBCs, two FDs with secondary ABC changes, one FD and one post-cement spacer removal state. Three of them had pathologic fractures. Progression of bone healing and mechanical support and functional result were evaluated. The mean follow-up period was 25.4 months. Results: Incorporations into host bones were progressed in all, average 4.2 months in six metaphyseal regions and 5.8 months in five diaphyseal regions respectively. Full structural supports were achieved in all except one patient without any additional procedures. No allograft-related complication was developed. Mean functional score according to the MSTS criteria was 29.6 at last follow up. Conclusion: Inlay cortical strut graft provided additional mechanical stability and bone stock for screw purchase in large cyst or cavitary defects of long bones, which allow early mobilization and excellent functional outcome.

• The Journal of the Korean bone and joint tumor society
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• v.16 no.1
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• pp.8-13
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• 2010

Purpose: This study was performed to evaluate the effi ciency of Platelet-rich plasma (PRP) for acceleration of bone healing process on allograft transplantation after curettage in benign bone tumor. Materials and Methods: From December 2007 to February 2009, twenty-one patients who had benign bone tumor and underwent allograft transplantation after curettage were evaluated. Mean follow-up period was 14.6 months (range, 12-26 months). We compared with 13 cases of PRP group and 8 cases of non-PRP group in terms of size of lesion, bone resorption, amount of applied PRP and complications. The mean age at surgery was 23.6 years (range, 4-73 years). The most common diagnosis was simple bone cyst (7) followed by enchondroma (4), giant cell tumor (3), undifferentiated benign bone tumor (3) and so on. Results: The mean size of lesion was 33.5 $cm^3$ (range, 2.3-181.9 $cm^3$) (29.4 $cm^3$ in PRP group and 40.2 $cm^3$ in non-PRP group). The mean volume of injected PRP was 7.4 cc (range, 3-12 cc). Bone union started at 3.0 months (range, 1.5-5.8 months) in PRP group and 5.3 months (range, 4-8 months) in non-PRP group. Three cases for each group were excluded due to recurrence and pathologic fracture. One patient had febrile episode 3 weeks later after surgery which subsided with antibiotics. Conclusion: The PRP could accelerate bone union in allograft transplantation after curettage of benign bone tumor. Furthermore, we expect that PRP can accelerate bone union in fracture or non-union.

• The Journal of the Korean bone and joint tumor society
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• v.13 no.1
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• pp.22-30
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• 2007

Purpose: We describe clinical, radiographic, MRI and pathologic findings as well as final outcome after simple curettage and bone graft of cystic fibrous dysplasia (FD) in the long bone, which has been rarely documented in the literature. Materials and Methods: Clinical records, radiographs, MRI and histologic slides of 11 patients with cystic FD in the long bone were retrospectively analyzed. Results: Six patients complained pain for several months, 4 patients presented pain after trivial injury event, and 1 patient suffered pathologic fracture. The mode of involvement was monostotic in 10 patients and polyostotic in l patient. The femur was affected in 7 patients, the humerus in 3, and the radius in 1. Radiography showed prominent, expansive lysis associated with ground-glass density of FD. MRI revealed 2 different signals of FD and cyst. Microscopic examination revealed classic findings of FD and non-specific cystic degeneration. The final outcome was satisfactory in every patient. Local recurrence was not observed. Conclusion: Cystic FD in the long bone seems not as rare as the scarcity of reported cases would indicate. MRI features provide a basis for differential diagnosis between benign cystic change and malignant transformation. Cystic FD would be an indication for surgery and simple curettage with allo-chip-bone graft is effective.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.4
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• pp.628-633
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• 2005

Deep caries in primary molars without early intervention frequently induce a pulpal disease and consequent furcation lesion with fistulous openings Up to now, majority of the textbooks on pediatric dentistry and literatures have described that extraction of the inflicted teeth is indicated for these cases and in reality these teeth have usually been extracted in the dental clinics. However when we recognize the excellent capacity of bone regeneration in children and the presence of numerous accessory canals at furcation areas, the removal of infection source in pulp by pulpectomy and inflammatory granulation tissues at furcation areas by furcal curettage might open the possibility of rapid healing at the furcation regions. In this report, 10 cases of primary molars in 3 to 6-year-old children with fistulous openings and furcation lesions in moderate size of 2 to 4mm in depth radiolucency at furcation lesion have been chosen. After pulpectomy and furcal curettage, evident bone regeneration was detected radiographically in all cases. Through the cases, we came to realize that all the cases previously described are not the indications of extraction and this approach could make many cases with pulp and furca combined lesions survive and remain healthy in the children's dental arches. However, in order for this approach to acquire objective appropriateness, it is thought that more scrupulous evaluation is desirable on the various factors regarding the indication such as the extent of furcation lesions, absorption status of teeth, amount of covering bone on succeeding teeth and so on.