• Restorative Dentistry and Endodontics
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• v.45 no.2
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• pp.13.1-13.10
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• 2020

Objective: The aim of this study was to evaluate the influence of different modeling agents on the surface microhardness (Vickers hardness number; VHN), roughness (Ra), and color change (ΔE) of a nano-hybrid composite with or without exposure to discoloration by coffee. Materials and Methods: Sixty-four cylinder-shaped nano-hybrid composite specimens were prepared using a Teflon mold. The specimens' surfaces were prepared according to the following groups: group 1, no modeling agent; group 2, Modeling Liquid; group 3, a universal adhesive (G-Premio Bond); and group 4, the first step of a 2-step self-adhesive system (OptiBond XTR). Specimens were randomly allocated into 2 groups (n = 8) according to the storage medium (distilled water or coffee). VHN, Ra, and ΔE were measured at 24 hours, 1 week, and 6 weeks. The Kruskal-Wallis test followed by the Bonferroni correction for pairwise comparisons was used for statistical analysis (α = 0.05). Results: Storage time did not influence the VHN of the nano-hybrid composite in any group (p > 0.05). OptiBond XTR Primer application affected the VHN negatively in all investigated storage medium and time conditions (p < 0.05). Modeling Liquid application yielded improved Ra values for the specimens stored in coffee at each time point (p < 0.05). Modeling Liquid application was associated with the lowest ΔE values in all investigated storage medium and time conditions (p < 0.05). Conclusion: Different types of modeling agents could affect the surface properties and discoloration of nano-hybrid composites.

• Fashion & Textile Research Journal
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• v.20 no.6
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• pp.690-703
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• 2018

The purpose of this study is to help user understand the basic principles and interfaces of each program, and to provide a base material for the development of more efficient apparel CAD systems to compensate for each program's shortcomings by comparing the function of three apparel CAD systems: Yuka CAD, Opti-tex, and Style CAD. For this purpose, the skirt waistband and sleeve armhole line creation process were selected based on these two criteria. 1) There is a big difference between principle and method between CAD systems. 2) When CAD system is used rather than paper drawing process, the process is shortened and convenience is high. In this study, pros and cons and supplement point of each CAD system are suggested by comparing the functions of the CAD system performing the selected drafting process by four criteria: icon, key, method, and characteristic point. As a result of the study, it was confirmed that the three CAD systems differ in the basic principle and interface environment. As a result of analyzing the skirt waistband method function, it was confirmed that the band line is formed directly on the outline of the skirt and the band dart recognition function is the most efficient function and as a result of the analyzing the sleeve armhole line method function, it was confirmed that the curve generation function using the shape of the actual curve measure and the length adjustment function through the automation of the dimension calculation is the most efficient function.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.999-1002
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• 2005

This paper describes an improved Rate-Distortion Optimization Algorithm for JPEG2000. We proposed a new optimal constant setting method and rate allocation method to reduce execution time of the rate control. And we proposed hardware structure of the improved R-D opti. algorithm. Consequently, improved Rate-Distortion Optimization algorithm is faster than conventional rate control scheme in JPEG2000 standard and have nearly same performance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.1
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• pp.21-26
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• 1991

the Bacillus subtilis LY-353 which secretes the protease isolated from seafoods. The opti-mum culture condition for production of protease from B. subtilis LY-353 was as follows ; tem-perature 35$^{\circ}C$ pH 7.5 salt concentration 1.0% The purification steps involved ammonium sulfate fractionation DEAE-Sephadex A-50 column chromatography and Sephadex G-100 gel filtration A 7.33 fold purification and 6.55 yield of protease was obtained from culture broth, The optimum pH and temperature for the enzyme action were pH7.5 and 55$^{\circ}C$ respecti-bely.

• Journal of information and communication convergence engineering
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• v.14 no.3
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• pp.163-170
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• 2016

Because of rapid technological advancements, increased data rate support has become the key criterion for future communication medium selection. Multimode optical fibers and multicore optical fibers are well matched to high data rate throughput requirements because of their tendency to support multiple modes through one core at a time, which results in higher data rates. Using the numerical mode solver OptiFiber, we have designed a concentric core fiber by investigating certain design parameters, namely core diameter (µm), wavelength (nm), and refractive index profile, and as a result, the number of channels, material losses, bending losses, polarization mode dispersion, and the effective nonlinear refractive index have been determined. Space division multiplexing is a promising future technology that uses few-mode fibers in parallel to form a multicore fiber. The experimental tests are conducted using the standard second window wavelength of 1,550 nm and simulated results are presented.

• Journal of Electrical Engineering and Technology
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• v.11 no.2
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• pp.508-518
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• 2016

In this paper, we propose a method combining an accelerometer with a cross structured light system to estimate the golf green slope. The cross-line laser provides two laser planes whose functions are computed with respect to the camera coordinate frame using a least square optimization. By capturing the projections of the cross-line laser on the golf slope in a static pose using a camera, two 3D curves’ functions are approximated as high order polynomials corresponding to the camera coordinate frame. Curves’ functions are then expressed in the world coordinate frame utilizing a rotation matrix that is estimated based on the accelerometer’s output. The curves provide some important information of the green such as the height and the slope’s angle. The curves estimation accuracy is verified via some experiments which use OptiTrack camera system as a ground-truth reference.

• Industrial Engineering and Management Systems
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• v.10 no.1
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• pp.1-6
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• 2011

This paper describes the issue of batch scheduling.In food production, the lead-time from produc-tion to sale should be decreased becausefreshness of the product is important. Products are shipped at diverse times depending on a demand of sellers, because the types of sellers has become diversified such as super-markets, convenience stores and etc. production of quantity demanded must be completed by time to ship it then. The authors consider a problem with due-dates constraints and construct the algorithm to find the opti-mal schedule that satisfy the due-dates constraint, batch size constraint, inventory time constraint and mini-mize total flow time.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2000.05a
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• pp.28-35
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• 2000

For the merit of a container in transportation and cargo handling the amount of container freight has been continuously on the increase. On the other hand container crane had got the bottle neck in cargo handling due to low productivity so that freight congestion had been often occurred at ports. in this paper A mathematical model for container crane system is represented a method for designing a fuzzy controller of container crane system for high productivity in cargo handling is presented. The fuzzy controller is compared with other optimal controller at the same condition. in the computer simulation the fuzzy controller obtained an excellent response to reference change better than the optimal controller. For disturbance such as a strong storm and parameter change due to change of cargo weight the result was also stable and robust than the optimal controller.

• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.841-843
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• 1998

The fiat fluorescent lamp(FFL) can be used to the LCD bat]flighting. In order to evaluate the discharge characteristics of FFL firing voltage, discharge current, luminance and CIE chromaticity with frequency were measured. The experimental results show that firing voltage decreased with increasing the frequency, discharge current increased with increasing the frequency. Luminance of FFL using Xe gas shown $2700\;cd/m^2$ in 700V rms, 80 kHz.

• Journal of Korean Home Economics Education Association
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• v.13 no.3
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• pp.13-22
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• 2001

The Purpose of this study is to enhance the efficiency of clothing-making units in the textbook of Home Economics for the high school students. I handed out a research paper with several questions to 75 teachers and 87 students to find out the realities of the education. There are several problems of making clothes at class: lack of time, appropriate equipment and efficient learning material. To solve these problems. I made a half-sized skirt kit utilizing OPTI Tex. a type of CAD in fashion design and copied it by silkscreen. and let the students use it. Both of the teachers and students showed positive response to the newly made kit of my own. saying that \"it is very handy to prepare and it\`s very helpful to figure out how to make skirt. \" Using the kit. we could reduce the time to make clothes by about 60 % and do well in the classroom without any sewing machines.