• Journal of the Economic Geographical Society of Korea
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• v.17 no.4
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• pp.632-645
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• 2014

This paper criticized the recent Korean 'creative economy policies' focused on regional developmental implications. Even though the policies targeted to promote ICT new startups and build virtuous circle of ICT industrial ecosystem in Korea as a whole, the outside regions of the Seoul-Busan industrial axis where the bases of ICT industries are very weak would suffer from systematic exclusion in ICT investments and deepening regional disparities. Second, ICT-centered policies would selectively affect or operate commensurate with the size of regions in this low-growth, after-financial crisis age. Third, the possibilities of regional insularity and lock-in in these low levels of 'related variety' regions would worsen the industrial competitiveness. Lastly, the policies should be reoriented to fortify region-based creative economic ecosystem based upon triple helix learning region.

• Journal of the Korean Wood Science and Technology
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• v.43 no.1
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• pp.112-121
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• 2015

In this study, Copper Azole (CuAz), a domestically available wood preservative for pressure treatment, was employed to perform an experimental research on its infiltration and decay properties in Japanese Red Pine. Test specimens were pressure-injected with CuAz-2 preservative to measure its preservative effectiveness, and then its impact on weight and mass losses. Furthermore, wood specimens were treated with CuAz-2 preservatives of various concentration levels before they were decayed with brown-rot-fungi in order to observe decay properties on light microscope (LM) and field emission scanning electron microscope (FE-SEM). As a result, untreated specimen by Fomitopsis palustris showed the mass loss of more than 40%, and the value of preservative effectiveness of CuAz-2 by indoor decay was $1,73-3.32kg/m^3$. The concentration levels of CuAz-2 preservative were shown to cause significant variations in terms of decay progresses in the cross section, radial section, and tangential section. By contrast, untreated specimens had underwent serious decays in early wood, late wood, longitudinal resin canals, and ray, which led to vertical destruction of wood texture. As for the radial section, ray tracheid, ray parenchyma cell, and window like pits were decayed and destroyed. In the case of tangential section, uniseriate rays and vertical resin canals were seriously decayed. In conclusion, this study indicates that the adequacy of the current CuAz injection amount should be reviewed in the domestic environment because there are significantly different decays at different decay conditions.

• Restorative Dentistry and Endodontics
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• v.31 no.6
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• pp.427-436
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• 2006

The objective of this study was to investigate the effects of various occlusal loads on the stress distribution of the buccal cervical region of a normal maxillary second premolar, using a three dimensional fnite element analysis (3D FEA). After 3D FE modeling of maxillary second premolar, a static load of 500N of three load cases was applied. Stress analysis was performed using ANSYS (Swanson Analysis Systems, Inc., Houston, USA). The maximum principal stresses and minimum principal stresses were sampled at thirteen nodal points in the buccal cervical enamel for each four horizontal planes, 1.0 mm above CEJ, 0.5 mm above CEJ, CEJ, 0.5 mm under CEJ. The results were as follows 1. The peak stress was seen at the cervical enamel surface of the mesiobuccal line angle area, asymmetrically. 2. The values of compressive stresses were within the range of the failure stress of enamel. But the values of tensile stresses exceeded the range of the failure stress of enamel. 3. The tensile stresses from the perpendicular load at the buccal incline of palatal cusp may be shown to be the primary etiological factors of the NCCLs.

• Applied Biological Chemistry
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• v.26 no.2
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• pp.75-81
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• 1983

The performance of the flat-plate solar collector with rock-pile thermal storage medium and the drying characteristics of rough rice and red pepper by use of natural air and of supplementary heated air by the solar drier were studied. The thermal efficiency of the flat-plate solar collector was average 25.4 percent and the overall heattransfer coefficient of the collector was approximately $38.13kJ/hr.m^2^{\circ}C$. The flat-plate collector was able to supply the supplementary heated air which was about $7^{\circ}C$ higher than the ambient air temperature during the daytime and about $3^{\circ}C$ higher than during the night. For rough rice drying of grain moisture content front 24.5 to 14.5%, it took 18 days in the natural air system, 12 days in the tubular solar collector and 10 days in the flat-plate solar collector. For red pepper drying from it's moisture from 81.0 to 15.0%, 68 hrs required under conventional sun drying system, but 38 hrs in tubular solar collector and 36 hrs in the flateplate solar collector. The changes of capsanthin and capsaicine content were investigated at various drying system, and little difference was found among the drying system.

• Fire Science and Engineering
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• v.31 no.5
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• pp.117-122
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• 2017

The absence of fire fighters' connection to communication can bring about increased loss of life due to errors and delays in rescue and actions and danger to their own safety. Therefore, when communication infrastructure has been destroyed in an enclosed space, it is necessary to set up an emergency wire or wireless telecommunication environment to fire fighting and to secure safer environment to deal with the disaster by checking the location of fire fighters. In this research, for the establishment communication environment in an enclosed inside using Ultra-Wide Band (UWB) wireless communication network, the performance of communication position determination of a single UWB communication module was evaluated regarding 6 kinds of indoor surroundings. When the communication distance in an indoor environment of each 6 channels bandwidth of UWB communication frequency was measured, the results were as follows: the open space (Ave. 15.5 m, Max. 20 m), the corridor (Ave. 17.33 m, Max 20 m), inside retaining home furnishings (Ave. 15.3 m, Max. 20 m), vertical stairs (Ave. 4.33 m, Max. 6 m), horizontal space with a closed fire door (Ave. 6.5 m, Max. 17 m). It was also found out that the communication function and the distance function were best in the frequency range from 6489.6 to 1081.6 MHz by 7 Ch. Accordingly, the establishment of communication environment in an enclosed space is judged to be possible when UWB communication module is set up at 20 m apart and multiple channels are used.

• The Journal of Engineering Geology
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• v.29 no.3
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• pp.279-288
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• 2019

The groundwater drawdown at each monitoring well near a radial collector well along Anseong Stream, Korea, was measured and compared with the calculated drawdown using the mirror well concept. The drawdown calculation is performed by treating the collector well as a large vertical well in a homogeneous isotropic aquifer. The measured drawdown at each monitoring well is slightly different from the calculated value due to anisotropy in the hydraulic conductivity and aquifer thickness. The difference between the measured and calculated values at Well OW-7 is large, reaching approximately 48 cm, because a horizontal well is not installed along this direction. Sensitivity analysis of the hydraulic conductivity and aquifer thickness indicates that the hydraulic conductivity is more sensitive to groundwater level changes. Groundwater level changes become a concern when a radial collector well with a large pumping rate capacity is installed, which highlights the need to thoroughly investigate the aquifer characteristics in the surrounding area.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.1
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• pp.76-84
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• 2019

This study evaluated the microleakage of three restorative materials and three tricalcium silicate-based pulp capping agents. The restorative materials were composite resin (CR), resin-reinforced glass ionomer cement (RMGI), and traditional glass ionomer cement (GIC) and the pulp capping agents were TheraCal $LC^{(R)}$ (TLC), $Biodentine^{(R)}$ (BD), and $ProRoot^{(R)}$ white MTA (WMTA). Additionally, shear bond strengths between the pulp-capping agents and dentine were compared. Class V cavities were made in bovine incisors and classified into nine groups according to the type of pulp-capping agent and final restoration. After immersion in 0.5% fuchsin solution, each specimen was observed with a stereoscopic microscope to score microleakage level. The crowns of the bovine incisors were implanted into acrylic resin, cut horizontally, and divided into three groups. TLC, BD and WMTA blocks were applied on dentine, and the shear bond strengths were measured using a universal testing machine. The microleakage was lowest in TLC + GIC, TLC + RMGI, TLC + CR, and BD + GIC groups and highest in WMTA + RMGI and WMTA + CR groups. The shear bond strength of BD group was the highest and that of WMTA group was significantly lower than the others.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.5
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• pp.127-134
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• 2021

When constructing a tunnel on a stable ground, stress is changed in the ground during excavation stage and installation of ground support materials. In the standards for safety evaluation of structures in use, it is suggested to perform numerical analysis reflecting the excavation stage. But method of seismic performance evaluation was not presented. Therefore, in this study, numerical analysis was performed with different analysis methods, and the results were compared and analyzed. As a result of the numerical analysis, seismic wave applied in the horizontal direction were no difference depending on the analysis methods. However, there was a big difference in the result according to the evaluation methods of tunnel member forces. When reviewing with the strength design method, the structure performance could be not satisfied depending on the existence or nonexistence of reinforcing bars. Based on these research results, it is suggested that the interpretation method should be clearly presented and reflected in the relevant standards.

• (The) Research of the performance art and culture
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• no.41
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• pp.69-92
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• 2020

This study describes the impact of early childhood teacher's artistic competence on art education pedagogy and improved curriculum design. Furthermore, the effect of drama as a way of improving early childhood teacher's artistic competence is explained. Many researchers have mentioned that early childhood is a period of sensitivity and potential. Therefore, it will be helpful if children meet a teacher who understands them and inspires their innate artistic sense at a level of their eyes. It explained which aspect of artistic competence should be focused for the teacher training education. There are many approaches to develop early childhood teachers' artistic competence. Adopting drama is one of them. The strong points of drama to improve their artistic competence are as follows. Firstly, human's movement and voice are the main artistic channel in drama. What we are doing in daily life is found are drama world. It means if early childhood teachers experience drama activity, they will feel more comfortable and intimate with it. In addition, early childhood teachers tend to be familiar with dramatic play, so they can more easily access to drama world. Secondly, drama will be helpful to understand different feelings and to broaden and deepen understandings of others' standpoints. For early childhood teachers, drama activity will be helpful to understand how dramatic art form works and to lead children's play in diversified and sincere way. In addition, drama activity will be useful to build horizontal and democratic relationships between children and the teacher. It is one of the main emphases of 2019 revised Nori national curriculum. To sum up, drama will be a excellent method to develop artistic competence for early childhood teachers. Thus, it is expected that They have more opportunities to experience drama as an art form.

• Journal of Korean Society of Forest Science
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• v.16 no.1
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• pp.33-62
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• 1972

Pitch pine (Pinus rigida Miller) in Korea has become one of the major silvicultural species for many years since it was introduced from the United States of America in 1907. To attain the more rational wood utilization basical researches on wood properties are primarily needed, since large scale of timber production from Pitch Pine trees has now been accomplishing in the forested areast hroughout the country. Under the circumustances, this experiment was carried out to study the wood anatomical, physical and mechanical properties of Pitch Pine grown in the country. Materials used in this study had been prepared by cutting the selected pitch pine trees from the Seoul National University Forests located in Suwon. To obtain and compare the anatomical and physical properties of the different parts of tree such as stem, branch, top and rootwood, this study had been divided into two categories (anatomical and physical). For the anatomical study macroscopical and microscopical features such as annual ring, intercellular cannal, ray, tracheid, ray trachid, ray parenchyma cell and pit etc. were observed and measured by the different parts (stem, branch, root and topwood) of tree. For the physical and mechanical properties the moisture content of geen wood, wood specific gravity, shrinkage, compression parallel to the grain, tension parallel and perpendicular to the grain, radial and tangential shear, bending, cleavage and hardness wree tested. According to the results this study may be concluded as follows: 1. The most important comparable features in general properties of wood among the different parts of tree were distinctness and width of annual ring, transition from spring to summerwood, wood color, odor and grain etc. In microscopical features the sizes of structural elements of wood were comparable features among the parts of tree. Among their features, length, width and thickness of tracheids, resin ducts and ray structures were most important. 2. In microscopical features among the different parts of tree stem and topwood were shown simillar reults in tissues. However in rootwood compared with other parts on the tangential surface distinctly larger ray structures were observed and measured. The maximum size of unseriate ray was attained to 27 cell ($550{\mu}$) height in length and 35 microns in width. Fusiform rays were formed occasionally the connected ray which contain one or several horizontal cannals. Branchwood was shown the same features like stemwood but the measured values were very low in comparing with other parts of tree. 3. Trachid length measured among the different parts of tree were shown largest in stem and shortest in branchwood. In comparing the tracheid length among the parts the differences were not shown only between stem and rootwood, but shown between all other parts of tree. Trachid diameters were shown widest in rootwood and narrowest in branchwood, and the differences among the different parts were not realized. Wall thickness were shown largest value in rootwood and smallest in branchwood, and the differences were shown between root and top or branchwood, and between stem and branch or top wood, but not shown between other parts of tree. 4. Moisture contents of green wood were shown highest in topwood and lowest in heartwood of stem. The differences among the different parts were recognized between top or heartwood and other parts of tree, but not between root and branchwood or root and sapwood. 5. Wood specific gravities were shown highest in stem and next order root and branchwood, but lowest in topwood. The differences were shown clearly between stemwood and other parts of tree, but not root and branchwood. However the significant difference is realized as most lowest value in topwood. 6. In compression strength parallel to the grain compared among the different parts of tree at the 14 percent of moisture content, highest strength was appeared in stem, next order branch and rootwood, but lowest in topwood. 7. In bending strength compared among the different parts of tree at the 14 percent of moisture content clearly highest strength was shown in branchwood, next order stem and root, but lowest in topwood. Though the branchwood has lower specific gravity than stemwood it was shown clearly high bending strength.