• Journal of Korea Water Resources Association
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• v.32 no.4
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• pp.447-455
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• 1999

In this study, the Bragg resonant of cnoidal waves propagating over a sinusoidally varying topography lying on a uniformly sloping beach is investigated. The governing equations derived from the Boussinesq equations are numerically integrated. The effects of fast varying terms and nonlinearity in reflection coefficients are also examined. Variation of reflection coefficient for different sloping beaches is studied. It is found that reflection coefficients are not strongly dependent on slopes of beaches.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.166-166
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• 2000

We studied electronic structure of magnetic semiconductors EuO, EuS, and EuTe. The photoemission spectra show localized Eu 4f states and broad anion p bands. As the size of anion increases from oxygen to tellurium, anion p band width increases and eventually overlaps Eu 4f states. Hence in EuO and EuS, Eu 4f states are the highest occupied stated lying above anion p band, while Te 5p band spreads widely over Eu 4f states to become valence band maximum in EuTe. It was also observed that Eu 4f states have width of 0.7eV and dispersion of 0.2eV in EuS by angle resolved photoemission spectroscopy. The width of the 4f spectra mainly originates from atomic multiplets, but the much larger dispersion than that of Eu metal is due to p-f mixing.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.139-139
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• 2000

We have investigated the adsorption and reaction of Cu(hfac)(vtms) on Cu(111) surface using TPD. The recombinative desorption of Cu(hfac)(vtms) reversibly occurs between 240 and 340K. The remaining Cu(hfac) after the desorption of vtms preferentially undergo the desorption between 330 and 370K as intact Cu(hfac) than the disproportionation reaction. The disprportionation reaction between adsorbed Cu(hfac) was observed to occur between 420 and 520K with an activation energy of 34~37 kcal/mol. the geometries and adsorption sites of Cu(hfac) have been also calculated by means of extended H ckel method. It is found that standing Cu(hfac) is more stable than lying-down Cu(hfac) on the Cu(111) surface and the Cu(hfac) molecule prefers to adsorb on the hollow site over the top or bridge sites. We also have investigated the surface modification effect by preadsorbed I and Na atoms on the reaction Cu(hfac)(vtms).

• Journal of Marine Bioscience and Biotechnology
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• v.3 no.1
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• pp.38-41
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• 2008

Fish is a major source of protein for the Senegalese population. Fishing plays a dominant role in the Government's policy towards generating employment. It currently generates about 100,000 direct jobs (fishermen) for nationals, of which more than 90% are in small-scale fishing. The fishing industry also contributes to Government revenue through different agreements. In addition to associated dues, fishing agreements imply a series of economic, trade and technical counterparts. Under the latest fishing agreement concluded by Senegal and the European Union (1997-2001), direct financial compensation amounts to about CFAF 32 billion. Despite its economic and social importance, the sector has to face serious disequilibria both in resource exploitation and market supply: the coastal demersal (deep lying fish) stocks with high market value (mostly exported) are fully and even over-exploited, with a serious risk of local market supply shortages looming ahead as the fishing effort shifts from locally consumed species to export-oriented ones.

• Physical Therapy Korea
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• v.14 no.1
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• pp.82-89
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• 2007

The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) is a valid and widely used instrument for the assessment of osteoarthritis patients. In this study, data was obtained from the out-patients with painful osteoarthritis of the knee. One hundred-three out-patients were interviewed by physical therapists. In an exploratory way, a Korean version of the KWOMAC was analyzed for unidimensionality, item separation, and item difficulty using the Winsteps programs. Ninety-five patients with osteoarthritis of the knee over 65 years were analyzed for Rash analysis. In the analysis several functional items poorly fit to the model. These items included "heavy domestic duties" and "standing". In the pain domain, one item ("at night while in bed") did not fit the model. In the stiffness domain one item ("after sitting, lying, or resting later in the day") did not fit the model. Although 4 items from the 3 domains (pain, stiffness, function domain) do not fit well, the KWOMAC domains were confirmed by Rasch analysis. Thus the KWOMAC needs to be further examined before it can be used to properly determine the health status of the elderly with OA.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.34 no.6
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• pp.247-257
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• 2022

In order to investigate the generations of rip currents modulated with the tidal elevations at a mega-tidal beach at the West Sea coast, numerical simulations of rip currents over the topography of the Daecheon beach were performed by using a Boussinesq-type wave and current model, FUNWAVE. The mega-tidal coast includes rocky outcrops (i.e., reefs) lying over or under the water surface according to the tidal elevations in the offshore and nearshore bathymetry. The offshore topographically-controlled rip currents were well reproduced due to the alongshore non-uniformities transformed by the tide-modulated topography. This study addressed the generation types of rip currents to occur at the mega-tidal coast with the tide-modulated outcrops and reefs.

• Journal of the Korean Operations Research and Management Science Society
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• v.38 no.4
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• pp.53-63
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• 2013

Together with soaring interest on Big Data, now there are vigorous reports that unearth various social values lying underneath those data from a number of application areas. Among those reports many are using such data as Internet search histories from Google site, social relationships from Facebook, and transactional or locational traces collected from various ubiquitous devices. Many of those researches, however, are conducted based on the data sets that are accumulated over the North American and European areas, which means that direct interpretation and application of social values exhibited by those researches to the other areas like Korea can be a disturbing task. This research has started from a validation study against Korean environment of the former paper which says an investment strategy that exploits up and down of Google search volume on a carefully selected set of terms shows high market performance. A huge difference between North American and Korean environment can be eye witnessed via the distinction in profit rates that are exhibited by the corresponding set of search terms. Two sets of search terms actually presented low correlation in their profit rates over two financial markets. Even in an experiment which compares the profit rates with two different investment periods with the same set of search terms showed no such meaningful result that outperforms the market average. With all these results, we cautiously conclude that establishing an investment strategy that exploits Internet search volume over a specified word set needs more conscious approach.

• Korean Journal of Materials Research
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• v.13 no.11
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• pp.711-716
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• 2003

Gate length, height, and silicide thickness have all been shrinking linearly as device density has progressively increased over the years. We investigated the effect of the cobalt diffusion during the silicide formation process on the 60$\AA$-thick gate oxide lying underneath the Ti/Co and Co/Ti bilayers. We prepared four different cobalt silicides, which have similar sheet resistance, made from the film structure of Co/Ti(interlayer), and Ti(capping layer)/Co, and peformed the current-voltage, time-to-break down, and capacitance-voltage measurements. Our result revealed that the cobalt silicide process without the Ti capping layer allowed cobalt atoms to diffuse into the upper interface of gate oxides. We propose that 100$\AA$-thick titanium interlayer may lessen the diffusion of cobalt to gate oxides in 1500-$\AA$ height polysilicon gates.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.1
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• pp.95-102
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• 1997

Ameloblastoma is the most agrressive ofht odontogenic tumors and it arises from the dental lamina or the derivatives of lamina. Ameloblastoma is a benign but locally invasive neoplasm consisting of proliferating odontogenic epithelium lying in a fibrous stroma. Usually the ameloblastomas are diagnosed in the forth and fifth decardes. Over 80% of them occur in the mandible, the remainder in the maxilla. The preferred treatment for ameloblastoma is radical excision, conserving(when possible. the inferior border of the mandible. The functional and esthetic rehabilitation of the partially edentulous patient may prevent the remaining structures from supporting conventional prosthetic treatment. Patients with long edentulous spans, malpositioned teeth, residual ridges defects and high muscle attachments may be offered an osseointegrated fixed prosthesis. Osseointegrated dental implants provide a viable alternative of tooth replacement. This is a case report of 16 year old female with ameloblastoma. We treated patient with radical excision, conserving the inferior border of the mandible and allogenous bone graft. The defected residual ridge area was reconstructed implants(Steri-Oss Implant System). the result was satisfactory.

• Proceedings of the KSRS Conference
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• v.1
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• pp.166-169
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• 2006

Our country's coast is vulnerable area to natural disaster which the repetitive damages occur every year including a loss of lives, the damage of facilities and erosion mostly except for the east coast because of a typhoon, tidal waves, sea water overflowing by topographic structure of low-lying gentle slope and shallow sea. However, as for prevention of natural disaster occurring every year, the situation is that it's centered on the restorationcentered measures and the general disaster prevention research to minimize damages at the time of disaster occurrence is insufficient. This study intendedlop t to devehe techniques possible for real time sampling of damage prediction areas on Web in order to support decision making for damage prevention and establishment of disaster prevention policy. For this, the thematic map was produced related to disaster based on high-resolution satellite picture, and the environmental DB similar to real world was constructed through topographic construction of three-dimension integrating the parts of land and the sea. In addition, the system was developed possible for the expression of damageable regions by real time grasp of dangerous regions at the time of disaster occurrence through over flowing simulation of three-dimension, and it's intended to prepare a basis to minimize damages to disaster situations through it.