• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.35-43
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• 2017

The minimum reinforcement ratio is an important design factor to prevent a brittle failure in RC flexural members. A minimum reinforcement ratio is presented by assuming an effective depth of cross-section and moment arm lever in CDC and KHBDC. In this study, it suggests that a rational method for minimum reinforcement ratio is calculated by material model and force equilibrium. As results, a minimum reinforcement ratio using a p-r curve in KHBDC is evaluated about 52~80% of recent design code's value and it induces an economical design. And also, a ductility capacity in case of placing this minimum reinforcement amount is evaluated about 89% of recent design code's value, but ductility in a member is 7 or more, so it has a sufficient ductility capacity. Therefore, it is judged that a minimum reinforcement ratio using p-r curve has a theoretical rationality, safety and economy in a flexural member design.

• Journal of the Korean Geotechnical Society
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• v.34 no.7
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• pp.29-38
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• 2018

Three-dimensional continuum modeling of dynamic soil-pile-structure interaction embedded in a liquefiable sand was carried out. Finn model which can model liquefaction behavior using effective stress method was adopted to simulate development of pore water pressure according to shear deformation of soil directly in real time. Finn model was incorporated into Non-linear elastic, Mohr-Coulomb plastic model. Calibration of proposed modeling method was performed by comparing the results with those of the centrifuge tests performed by Wilson (1998). Excess pore pressure ratio, pile bending moment, pile head displacement-time history according to depth calculated by numerical analysis agreed reasonably well with the test results. Validation of the proposed modeling method was later performed using another test case, and good agreement between the computed and measured values was observed.

• The Research Journal of the Costume Culture
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• v.26 no.3
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• pp.265-281
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• 2018

Government policy supporting the fashion industry in Korea has focused on the future development of rising fashion designer's brands, and as a part of this support, several Fashion Creative Studios are presently operated. The purpose of this study is to identify the meaning of these facilities and suggest development strategies for their effective utilization. This paper presents a conceptual understanding based on a literature review, and deduces the direction of Fashion Creative Studios through an exploratory analysis of various case studies and in-depth interviews with five designers, who have graduated from the Seoul Fashion Creative Studio. The results are as follows. Firstly, fashion educational institutions have to provide sufficient information about the Fashion Creative Studios to students. They can also consider adding short-term residencies to the curriculum in which students prepare collections or portfolios for the studios. Secondly, Fashion Creative Studios are required to intensify business and marketing programs to increase real-world support. It would be helpful to provide 1:1 management programs with several segmented stages for the design brands, or connect them to investors who could provide financial support and business expansion. Thirdly, Fashion Creative Studios need to find a way to strengthen textile differentiation and craft characteristics to increase designer brand competitiveness. Broadening participation with textile designers, connecting with experts and ateliers, and promoting collaboration with artists and artisans in the Arts Creative Studios can be further examined to this end.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.1049-1057
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• 2020

The shift from elite education to mass education in Vietnam has met the demand for education for everybody as well as for quality human resource talent for an emerging nation. Under the resource constraint, understanding the quality dimensions of education and its priority level is important for effective and efficient policies. This study was carried out using both qualitative and quantitative methodologies to develop quality criteria and a ranking model. Two rounds of in-depth interviews were conducted with fifteen experts in the field, who were rectors, employers, and recruitment specialists to develop the quality framework applied in Vietnamese universities under total quality management (TQM), starting from the input of the senior secondary school leavers, through a teaching process to the output. The first round of interviews were unstructured questionnaires designed to explore the main factors in quality assessment model. The second round affirmed the experts' agreement on the assessment model. Then, fuzzy logic was applied to rank eight criteria in the quality assessment model into priority order: cost, teaching and administrative staff, leadership, curriculum, student-related factors, internationalization, admissions, and campus. The results are critical for identifying the necessary actions to enhance the education quality and to further research on the optimal quality model.

• Restorative Dentistry and Endodontics
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• v.31 no.5
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• pp.352-358
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• 2006

The purpose of this study was to investigate the influence of thickness on the degree of cure of dual-cured composite core. 2, 4, 6, 8 mm thickness Luxacore Dual and Luxacore Self (DMG Inc, Hamburg, Germany) core composites were cured by bulk or incremental filling with halogen curing unit or self-cure mode The specimens were stored at $37^{\circ}C$ for 24 hours and the Knoop's hardness of top and bottom surfaces were measured. The statistical analysis was performed using ANOVA and Tukey's test at p = 0.05 significance level. In self cure mode, polymerization is not affected by the thickness. In Luxacore dual, polymerization of the bottom surface was effective in 2, 4 and 6 (incremental) mm specimens. However the 6 (bulk) and 8 (bulk, incremental) mm filling groups showed lower bottom/top hardness ratio (p < 0.05). Within the limitation of this experiment, incremental filling is better than bulk filling in case of over 4 mm depth, and bulk filling should be avoided.

• Journal of Periodontal and Implant Science
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• v.38 no.2
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• pp.231-236
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• 2008

Purpose: The treatment of gingival recessions is needed to reduce root sensitivity and improve esthetical satisfaction. Several surgical techniques have been proposed to achieve these goals. The use of connective tissue grafts has made esthetic root coverage a predictable procedure. Numerous clinical studies have represented that using connective tissue grafts to cover exposed root surface showed high success rates. This is a case report which demonstrates the technique to obtain root coverage of a buccal recession defect. Materials and Methods: A 35-year-old patient with a high level of oral hygiene was selected for the study. This patient had one Class I Miller recession defect in the mandible. A coronally advanced flap in combination with the connective tissue graft was chosen for the treatment. After surgery, the patient was told to visit the hospital once a week for his oral management and professional prophylaxis. The depth of initial recession was 4.0 mm. Result: After three months, it reduced to 0.0 mm, and the average recession reduction was 4.0 mm. The average root coverage was 100%. Conclusion: The connective tissue graft is both effective and predictable way to produce root coverage in increasing the width of CAL and KT of various adjacent gingival recessions.

• Journal of Korea Water Resources Association
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• v.45 no.1
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• pp.53-64
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• 2012

In this study (II), the module developed in the previous study (I) has been tested on application and numerical stability. The runoff module was compared the result of analysis with two different models (FFC2Q and $Vflo^{TM}$) considering characteristic of infiltration. To examine the application and stability of developed module, runoff aspect was simulated under the variety case of rainfall intensity, effective soil depth, elapsed time. The development module was presented typical type of infiltration process looking physically, the different of saturation point on soil type, and characteristic of soil type. Also, the module was reflected in the runoff feature about rainfall intensity and time distribution. Finally, this paper drew a conclusion that result of rainfall-runoff analysis as compared with difference models (FFC2Q and $Vflo^{TM}$) has a high accuracy.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.1 no.1
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• pp.18-27
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• 1998

To investigate the restoration progression on soil physical properties and vegetation at the surface of logging road affected by timber harvesting operation. This study was carried out at logging roads constructed from 1989 to 1994 in Mt. Baekwoon, Kwangyang, Chollanam-do. Judging from the analysis of soil hardness, there were significant changes in the depth of soil between 5 and 10cm. Soil hardness was recovered from the compacted condition to the natural forest condition after 9 years passed. Soil macroporous ratio (pF2.7) of topsoil was higher than that of deep soil. Soil moisture retention of topsoil was more improved than that of deep soil. From the view of soil bulk density, the necessary time for recovering to the undisturbed condition of forest soil was about 10 years in the logging road left. Soil physical properties such as soil bulk density and porous ratio were recovered as time passed. Improved soil physical properties promoted the plant recovery on the logging road surface. The dominant species on the logging roads were Comus kousa, Prunus sargentii as overstory species, Rubus crataegifolius, Lespedeza bicolor as understory species, and Saussurea gracilis, Pteridium aquilinum var. latiusculum as herbaceous species. The plant recovery of bank-slopes was faster than that of cut-slopes and road surface. In progress of year, average plant coverage were 70 to 90% in cut- and bank-slopes and 30 to 60% on the logging road, surface which was elapsed 9 years after logging road construction. Therefore, additional planting and seeding work could be effective to the soil condition and vegetation restoration.

• Journal of the Korean Institute of Navigation
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• v.5 no.2
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• pp.1-39
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• 1981

A doppler log is the typical device which can measure the ship's speed over the ground directly, by means of doppler effect of the underwater ultrasonic wave, which involves the error due to the sea bottom inclination, the trim and the incorrect transducer installation etc. The present doppler log adopts a single transducer, faced in the direction of themain beam, and therefore it is unable to correct the beam direction to eliminate the above mentioned error. Moreover, the frequencyis also limitted in a comparatively high range for getting a sharp beam with single transducer, and the speed over the ground can not be detectable at the deep sea, for an instance, over 200 meters. This paper describes a theoretical consideration for the doppler log error and an analysis by a computer on the observed speed data by a full size model ship. The result is verified that the most of doppler log error is caused by the ultrasonic beam angle of transducer. To eliminate the doppler log error due to the incorrect transducer installation and also to sharpen the beam for lower frequency range to expand measurable sea depth, this paper proposes a method of controlling the directivity adopting a linear transducer array and of controlling the directivity by the control of exciting current, and investigates by the computer simulation and make experiment with magnetostrictive ferrite transducer of 28, 50 and 75KHz. The experimental results are shown well coincide with the measured ones, and they are revealed that in case where the transducer interval is greater than 1 wavelength, the effective control of the beam direction is hardly performed with keeping adequate beam width and side lobe level. It is concluded that 6-elements array with inter element space of a half wavelength can make comparatively sharp beam and low side lobe level. The results obtained here will contribute very much to the improvement of the performance of doppler log.

• Health Policy and Management
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• v.22 no.4
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• pp.561-578
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• 2012

This study was performed in order to compare a change in pharmaceutical expenditures per outpatient of clinic and to analyze factors relevant to a systems as part of evaluating policies for the incentive scheme to reduce total prescribed drug expenditure and for the drug utilization review system("DUR system" hereafter). For this, it had finally analytical subjects as 21,320 clinics nationwide without a change in location, clinics symbol and signed subject during both terms of the first half of 2010 and the first half of 2011. As a result, the odds ratio with reduction in pharmaceutical expenditures of clinic was statistically higher significantly in the shorter year number of opening clinic, in the larger number of doctors, when the classification of establishment is other, not individual, and when the signed subject is surgical division. Also, the odds ratio was significantly higher in the less patient number of clinic and in the lower ratio of patients aged over 65. Finally, the odds ratio was significantly high when a clinic had been located in DUR system demonstrative project area. Through this, a case of policy for improvement in doctor's autonomous prescription behavior like DUR system can be known to be effective for reduction in pharmaceutical expenditures. A future research on evaluation of policy for pharmaceutical expenditure management system will need to be performed in-depth analysis in consideration of diverse characteristics on the participatory entities.