• The Journal of Advanced Prosthodontics
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• v.12 no.3
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• pp.140-149
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• 2020

PURPOSE. This study evaluated the color stabilities of two computer-aided design and computer-aided manufacturing (CAD/CAM) blocks and a nanofill composite resin and the microtensile bond strength (µTBS) between the materials. MATERIALS AND METHODS. Twelve specimens of 4 mm height were prepared for both Lava Ultimate (L) and Vita Enamic (E) CAD/CAM blocks. Half of the specimens were thermocycled (10,000 cycle, 5° to 55℃) for each material. Both thermocycled and non-thermocycled specimens were surface treated with one of the three different methods (Er,Cr:YSGG laser, bur, or control). For each surface treatment group, one of the thermocycled and one of non-thermocycled specimens were restored using silane (Ceramic Primer II), universal adhesive (Single Bond Universal), and nanofill composite resin of 4-mm height (Filtek Ultimate). The other specimens were restored with the same procedure without using silane. For each group, 1 × 1 × 8 mm bar specimens were prepared using a microcutting device. Bar specimens were thermocycled (10,000 cycle, 5° to 55℃) and microtensile tests were performed. Staining of the materials in coffee solution was also compared using a spectrophotometer. Data were analyzed using one-way ANOVA, t-test and post-hoc Scheffe tests. RESULTS. µTBS were found similar between the thermocycled and non-thermocycled groups (P>.05). The highest µTBS (20.818 MPa) was found in the non-thermocycled, bur-ground, silane-applied E group. Silane increased µTBS at some E groups (P<.05). Composite resin specimens showed more staining than CAD/CAM blocks (P<.05). CONCLUSION. CAD/CAM blocks can be repaired with composite resins after proper surface treatments. Using silane is recommended in repair process. Color differences may be shown between CAD/CAM blocks and the nanofill composite after a certain time period.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.6
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• pp.1269-1276
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• 2015

The methodology of utilizing Intensity-Duration-flood Quantity (IDQ) curve for flood alert and warning was introduced and its performance was evaluated. For this purpose the lumped parameter model was calibrated and validated for gauged basin data set and the index precipitation equivalent to alert and warning flood was estimated. The index precipitation and IDQ curves associated by three different Antecedant Moisture Conditions (AMCs) are made provision for various possible flood scenarios. The test basin is Wonju-cheon basin ($94.4km^2$) located in Gangwon province, Korea. The IDQ curves corresponding to alert (50% of design flood level) and warning (70% of design flood level) level was estimated using the Clark unit hydrograph based lumped parameter model. The performance evaluation showed 0.704 of POD (Probability of Detection), 0.136 of FAR (False Alarm Ratio), and 0.633 of CSI (Critical Success Index), which is improved from the result of IDQ with single fixed AMC.

• Journal of Fashion Business
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• v.18 no.6
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• pp.38-56
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• 2014

This study compared the flared skirts on 3D simulation and in real to show diverse forms in women's clothing depending on the body's gait and motion. By finding the problems, we suggested the possible methods for utilizing the 3D simulation in the clothing industry. First, the 3D simulation of flared skirts showed similar forms of appearance according to the flare length and volume. However, virtually formed drape shape was even in size and spacing, whereas it was not even in real. Second, according to the results of appearance test on the length and flare volume at $90^{\circ}$ and $180^{\circ}$, both real and 3D simulation skirts were evaluated to have outstanding appearances regardless of the skirt length. However, as the flares volume increased, the skirts with longer length were evaluated to have superior appearances compared to the skirts of shorter length. Third, it showed higher resemblance between the real and virtual simulation, when the skirt had less flare and as the skirt length shortened. However, it showed greater difference between the real and virtual simulation when flare volume and length increased. The length and volume of the skirt and the physical properties of the material are predicted to be different between the real and virtual simulation. However, they usually are similar in forms, so it is believed possible to use for predicting the design's silhouette or the feel when it is worn. This method can be applied on internet shopping malls, which can possibly reduce unnecessary time and expenses.

• Journal of the Korean Wood Science and Technology
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• v.19 no.3
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• pp.62-71
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• 1991

An evaluation of bending test of composite I and Box beams for determining the ultimate strength limit design criteria was presented. Maxium loads of composite I beams were found in beams composed of thicker upper flanges and/or vertical LVL flanges. These loads of plywood web beams were greater than those of PB web beams. Maximum loads of unsymmetrical box beams were less than those of symmetrical box beams. Thus, it took on different phase in box type beams. Ultimate loads of composite beams were greater than those of solid. The failure of composite beams were abrupt and failure mode was classified into following categories; Edgewise shear failure in web, delamination in flange-web joint, tension failure and tearing in LVL flanges, and web delamination. These failures of composite beams were appeared at the mixed mode. The influence factor affecting the performance of tested composite beams was shear strength of PB-web composite beams and compressive strength in plywood-web composite beams. It was also assumed that the influence factors on structural performance on composite beams were flange quality, web material and geometry of cross section. As one of the design methods resisting to compressive stress that was required in the case of small span to depth ratio and deep beams. composite I-beams composed of thicker upper flanges comparing to lower flanges were very effective in structural performance.

• Journal of Korea Multimedia Society
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• v.15 no.4
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• pp.552-559
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• 2012

Operating Systems is a discipline which handles complex and concepts related to its components and how an operating system works. However, most of the OS courses have been textbook-oriented theoretical classes. Therefore, many instructors have tried to make use of educational tools to help students understand a lecture and arouse their interests consistently. This paper describes the design and implementation of a web-based page replacement simulator which shows the process of page replacement algorithms visually. The academic achievement evaluation and t-test results for 2010's students and 2011's show that the differences of the correct answer ratios for the exam about page replacement algorithms and the scores between two groups are meaningful. And the results of survey show that a page replacement simulator is useful as an educational tool which causes the interests about operating systems and enhances the understanding of a lecture.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.2
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• pp.89-96
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• 2007

The bobbin probe examination is basic and the important method among other ECT techniques for the steam generator tube integrity assesment that is practiced during each plant outage. The bobbin probe is one of the essential components which consist of the whole ECT examination system, and provides us a decisive data for the evaluation of tube integrity in compliance with acceptance criteria described in specific procedures. The selection of examination probe is especially important because the quality of acquired ECT data is determined by the probe design characteristics, such as geometry and operation frequency, and has enormous effects on examination results. In this study, An optimal differential bobbin probe is designed for the steam generator tube inspection in nuclear power plants(NPPs). Based on the test results for electrical and ECT signal characteristics, the prototype bobbin probe satisfies all the criteria.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.7 s.155
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• pp.1090-1102
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• 2006

The purpose of this study is to develop an improved work clothing which is much safe, comfortable, mobility and convenient than what workers currently wear at construction site. The investigation has been conducted to evaluate current work clothing to grasp any problems, discomforts and damages related to the work clothing. For the best and accurate data, hands-on investigation and a short-interview have been performed at the construction site as well as formulating a questionnaire. The questionnaires was answered by 425 workers and safety manager of 13 different construction site. The result of the questionnaire enables us to design a sample work clothing, many pa π s such as material, pattern and design have been improved. To improve the amenity of heat, the surface of a material was used by $Aerocool^{\circledR}$ fiber which contains inside dryness function. In order to absorb perspiration on the back the armpits, mesh martial that is mixture of $Coolever^{TM}$ fiber and $Mirawave^{TM}$ fiber was used to absorb perspiration in an effective manner. And a sleeve's bottom part and trousers' bottom part's cover method have been changed. Sample work clothing was shorten at the side of upper garment up to 2cm and lengthen the length of the back by 3cm. To reduce the tightness around armpit more room was given in that area. Darts were added to the elbow, the hip, and the knees that also followed an ergonomic pattern. A sample work clothing evaluated an objective assessment and subjective assessment to compare to a current work clothing. Assessment group consists of seven subject groups and nine expert groups to evaluate external appearance and adaptability to the movements. In all aspects of the test, the result of evaluation process of the sample work clothing received more positive assessment than the current work clothing.

• Korean Institute of Interior Design Journal
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• v.19 no.5
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• pp.165-172
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• 2010

Recently, the recognition is changing about cultural heritage, and the various types of buildings or facilities of modern or contemporary times have been designated as cultural properties after that Registered Cultural Properties System is enforced. The purpose of this study is to survey how the newly born the historic buildings of modern or contemporary times through the remodeling process of the Studio 'Byeol'(the Training Center for Performers of Korean Traditional Music) in the National Theater of Korea so-called a microcosm of performing arts history. In the process, it will examine the merits and demerits of various alternatives and the direction of the remodeling etc., and propose an utilization as a basic data of post evaluation for the remodeling of a historic building. The result are as followings. Firstly, the remodeling that gave a new physical properties to a building can be used a method of conservation and reuse on a historic building. The remodeling of a historic building must be eclectically progress between the owner and the citizen or the economic value and the historicity conservation. And, the remodeling of historic buildings such as the Training Center for Performers of Korean Traditional Music must consider the conservation of the exterior walls in whole or in part at least. Secondly, an architect Lee Hee Tae(李喜泰) who had been to develop his own architectural vocabulary and to test based on the korean traditional architecture and the Training Center for Performers of Korean Traditional Music must be newly evaluated today. Lastly, the remodeling alternatives of the Training Center for Performers of Korean Traditional Music have been analyzed with three types, which is 'repairing only the interior which maintains the size and an appearance of present', 'extending the outer wall to the external column line', 'extending the basement'. And, it was analyzed with the appropriate final decision that it remodels only the interior in the current situation because of a historicity, a budget, a relevant law etc.

• Korean Journal of Human Ecology
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• v.21 no.1
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• pp.151-163
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• 2012

The purpose of this study was to examine the effects of perceived fit and brand transfer on extension evaluation in luxury fashion brands. The instrument for this research was a self-administered questionnaire based on a previously developed scale. The variables addressed in this scale included perceived fit, brand value for both parent brand (clothing) and extension brand (home line), extension brand association, and purchase intention of the product in extension brands. The participants in this research comprised of 215 female consumers between the ages of 19 and 51 demographically distributed nationwide. Data were analyzed by descriptive statistics, paired t-test, factor analysis, and regression analysis via SPSS 12.0. Findings showed that brand value consisted of two factors: cognitive and hedonic value in luxury fashion brands. Parent brand value was significantly related to perceived fit with a positive effect on brand association and hedonic value in extension brands. With respect to brand transfer, cognitive value of the parent brand increased the extension brand's cognitive value, while hedonic value of the parent brand increased the extension brand's hedonic value. In addition, purchase intention of the product in the extension brands was determined by the perceived fit and hedonic value of extension brands. This study also discusses the managerial implications for marketers in developing effective luxury brand extensions into new product categories, which leads to a synergy effect in building brand equity in the luxury fashion market.

• Structural Engineering and Mechanics
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• v.56 no.1
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• pp.27-47
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• 2015

In this study, the accuracy and reliability of fully nonlinear method against equivalent linear method for dynamic analysis of soil-structure interaction is investigated comparing the predicted results of both numerical procedures with the results of experimental shaking table tests. An enhanced numerical soil-structure model has been developed which treats the behaviour of the soil and the structure with equal rigour. The soil-structural model comprises a 15 storey structural model resting on a soft soil inside a laminar soil container. The structural model was analysed under three different conditions: (i) fixed base model performing conventional time history dynamic analysis, (ii) flexible base model (considering full soil-structure interaction) conducting equivalent linear dynamic analysis, and (iii) flexible base model performing fully nonlinear dynamic analysis. The results of the above mentioned three cases in terms of lateral storey deflections and inter-storey drifts are determined and compared with the experimental results of shaking table tests. Comparing the experimental results with the numerical analysis predictions, it is noted that equivalent linear method of dynamic analysis underestimates the inelastic seismic response of mid-rise moment resisting building frames resting on soft soils in comparison to the fully nonlinear dynamic analysis method. Thus, inelastic design procedure, using equivalent linear method, cannot adequately guarantee the structural safety for mid-rise building frames resting on soft soils. However, results obtained from the fully nonlinear method of analysis fit the experimental results reasonably well. Therefore, this method is recommended to be used by practicing engineers.