• Journal of Dental Rehabilitation and Applied Science
• /
• v.36 no.1
• /
• pp.48-54
• /
• 2020

In the case of crown-root fracture due to traumatic injury in anterior tooth and the fracture margin is located subgingivally, forced eruption has been proposed for the reconstruction of deficient bone and soft tissue. Forced eruption is one of the easiest orthodontic approaches that can have an acceptable outcome and prognosis, and has a low incidence of relapse. However, using heavy forces or very fast movements can also cause tissue damage or ankylosis. The following case reports present forced eruption as treatment option of crown fracture in maxillary anterior teeth.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.9 no.4
• /
• pp.447-454
• /
• 2014

Recently most of functional synthesis methods for quantum circuit realization have a tendency to adopt the declarative functional expression more suitable for computer algorithms, so it's difficult to analysis synthesized quantum functions. This paper presents a new functional representation of quantum circuits compatible with simple architecture and intuitive thinking. The proposal of this paper is a new functional synthesis development by using the control functions as the power of corresponding to affine-controlled quantum gates based on the mathematical substitution of serial-product matrix operation over the target line for the arithmetic and modulo-2 ones between power functions of unitary operators. The functional synthesis algorithm proposed in this paper is useful for the functional expressions and synthesis using both of reversible and irreversible affine-controlled NCV-quantum gates.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.2
• /
• pp.651-657
• /
• 2010

Even though local governments are committed to the landscape management aiming to enhance the quality of the urban and natural landscape, the results are not satisfactory since the landscape plan is performed through the "routine" process, on which the planning system is based. Many local governments had spent much in making their landscape plans, but these plans were evaluated not so much "useful" in the practical sense. The objective of the study, which aims to systematically readjust the existing landscape management system of Korea, is to analyse the landscape plans of the few local governments, which are categorized in two level - upper and low local government. The analysis of landscape plan is performed in terms of four factors: The composed structure, the objects of the plan, the effectiveness of the landscapeindicators and guidelines and the institutional system.

• Journal of IKEEE
• /
• v.22 no.2
• /
• pp.427-431
• /
• 2018

This research was worked about $Ga_2O_3$ Epi wafer that was one of the mose wide band gap semiconductors to be used power semiconductor industry. This wafer was grown $5.3{\mu}m$ thickness on Sn doped $Ga_2O_3$ Substrate by HVPE(Hydride Vapor Phase Epitaxy). Generally, we can fabricate 600V class power semiconductor devices when the thickness of compoound power semiconductor is $5{\mu}m$. but in case of $Ga_2O_3$ Epi wafer, we can obtain over 1000V class. As a result of J-V measurment of the grown $Ga_2O_3$ Epi wafer, we obtain $2.9-7.7m{\Omega}{\cdot}cm^2$ on resistance. Specially, in case of reverse, we comfirmed a little leakage current when the reverse voltage is over 200V.

• Journal of the Korean Chemical Society
• /
• v.58 no.6
• /
• pp.658-666
• /
• 2014

This study was designed to explore pre-service secondary science teachers' understanding and views of argument-based inquiry approach. Participants were 17 pre-service secondary science teachers enrolled in chemistry curricular materials and teaching methods course for majors in the college of education at a university in Seoul. Main data sources included each student responses to an open ended survey and individual interviews. Data analyses indicated that the pre-service teachers had very limited and biased understanding on scientific inquiry at the beginning of the semester. While the pre-service teachers understood that scientific inquiry should be an essential component of science teaching, a few pre-service teachers mentioned 'argumentation' or 'discussions' when they defined what scientific inquiry is. The majority of the pre-service teachers mentioned that science should be taught through scientific inquiry since science is inquiry itself. However, the pre-service teachers expressed several potential barriers and their concerns on implementing argumentation in scientific inquiry. While they concerned about students' lack of participation at the beginning of the semester, they concerned more about the teachers' ability of leading student argumentation at the end of the semester.

• Journal of the Korean Geotechnical Society
• /
• v.21 no.2
• /
• pp.137-144
• /
• 2005

A direct shear test is classified roughly by one side simple shear test of confining horizontal displacement type and torsional shear test of non-confining one. Direct shear test that has been widely used so far has some problems with test apparatus, testing and the analysis, and in particular that its strength value is everestimated in sandy soils. Also, progressive failure of shearing process happens from shear apparatus restriction and because the shear strain and shear stress are erratic in specimen, we can not define the shear strain value. In the meantime, a simple shear test having advantage of direct shear test is an ideal test method that can get stress-strain relation on shear because it can deliver constant shearing deformation to specimen. However, simple shear test cannot be used practically, because its structure makes tester manufacturing difficult. This paper described a on outline of test apparatus, improvement of test method, and constant pressure test results based on the obtained from improved direct shear apparatus and the standardization of JGS soil testing method.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.5 no.3
• /
• pp.279-289
• /
• 2003

In karst formation area, the tunnel support system is an important factor for the tunnel safety during operation. It is also not easy to determine the tunnel supporting system in the design stage. Therefore, it is necessary to standardize the tunnel supporting system in uncertain ground condition. This paper presents the standardization of the tunnel supporting systems to be adopt in karst formation. For the tunnel planned in the project area, karst features and the expected scenarios in the tunnel area were developed based on the results of the geological and geotechnical assessment. In order to provide specific supporting system and construction details for a wide range of possible karst features, the generalized typical support systems are developed according to the classification of karst features. In addition, the initial support systems and construction sequence for each karst feature are also presented in this paper.

• Composites Research
• /
• v.24 no.5
• /
• pp.9-16
• /
• 2011

This paper describes the crashworthiness evaluation and performance improvement of tilting train made of sandwich composites. The applied sandwich composite of carbody structure was composed of aluminum honeycomb core and glass/epoxy & carbon/epoxy laminate composite facesheet. Crashworthiness analysis of tilting train was carried out using explicit finite element analysis code LS-DYNA 3D. The 3D finite element model and 1D equivalent model were applied to save the finite element modeling and calculation time for crash analysis. The crash conditions of tilting train were conducted according to four crash scenarios of the Korean railway safety law. It found that the crashworthiness analysis results were satisfied with the performance requirements except the crash scenario-2. In order to meet the crashworthiness requirements for crash scenario-2, the stiffness reinforcement for the laminate composite cover and metal frames of cabmask structure was proposed. Consequentially, it has satisfied the requirement for crash scenario-2.

• Journal of Radiation Protection and Research
• /
• v.34 no.2
• /
• pp.69-75
• /
• 2009

To obtain precise information about characteristics of gamma ray detector system responses, we developed new GUI computer program to analize full-energy absorption peak using our developed Delphi computer code for educational purpose. By use of the well known 4 nonlinear peak shaping functions, peaks were fitted with least square fit method in this code. In this paper, we described the methods to search for 12 coefficients in above 4 nonlinear peak shaping functions by use of our developed code in details. The computer code was tested for 1 $\mu$Ci $^{137)Cs$ 661 keV gamma ray peak spectrum detected by 25 % relative efficiency HPGe detector with 5.35 cm (D) $\times$ 5.5 cm (L) size.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.30 no.4C
• /
• pp.185-191
• /
• 2010

Volumetric pressure plate extractor (VPPE) can be used for measurement of the soil-water characteristic curve in the laboratory using the axis-translation technique. The volume of extracted water from the soil specimen in VPPE can be measured continuously during the test without stoppage of air pressure for the measurements. However, the water volume measurement in VPPE using an air trap, a ballast tube, a burette, and a vacuum device so as to maintain a constant pore-water pressure in the soil specimen, is quite complicated and tedious. In order to improve the measuring problems of VPPE, a modified volumetric pressure plate extractor (MVPPE) was developed and tested on residual soil specimens. In addition, the modified apparatus can measure the volume of the extracted water using both Method A and Method B of ASTM D 6836-02 depending on the range of matric suction. Measuring principles and the improvements of MVPPE and typical results obtained from the tests are discussed in the paper.