• The Journal of Advanced Prosthodontics
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• v.10 no.4
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• pp.271-278
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• 2018

PURPOSE. The purpose of this in vitro study was to evaluate the effect of abrasive toothbrushing on the surface properties of monolithic computer-assisted design and computer-assisted manufacturing (CAD/CAM) materials stored in food-simulating liquids (FSLs). MATERIALS AND METHODS. Fourty-eight disk-shaped test specimens of each material (Paradigm MZ100/PMZ, Lava Ultimate/LU, Vita Enamic/VE, and Vita Mark II/VMII) with a diameter of 10.0 mm and a thickness of $3.0{\pm}0.05mm$ were prepared. Specimens were divided into 4 subgroups (n=12) and stored in air, distilled water, 0.02 M citric acid, or 75% ethanol/water solution for 7 days at $36.5^{\circ}C$. Then, the specimens were brushed in a multi-station brushing machine under a vertical load of 2.0 N for 3 hours. Surface gloss (GU), roughness (Ra), and hardness (Vickers [VHN]) were measured after storage and brushing simulation. The data sets were statistically analyzed with 2 and 3-way ANOVAs followed by the Tukey's post-hoc comparisons (${\alpha}=.05$). RESULTS. Statistically significant difference was found among the materials concerning the results of surface properties. VMII showed the highest VHN, while PMZ produced the lowest. Storage in FSLs significantly affected the VHN of PMZ and LU. VMII showed the lowest Ra and highest GU irrespective of FSLs and of abrasive toothbrushing. VE, LU, and PMZ produced significant decrease in GU and increase in Ra after toothbrushing. CONCLUSION. Surface properties of monolithic CAD/CAM restorative materials were differently affected by the storage media and abrasive toothbrushing.

• Korean Journal of Construction Engineering and Management
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• v.5 no.2 s.18
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• pp.181-193
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• 2004

A life cycle cost analysis model for public water supply systems should be different from the ones for other civil and architectural facilities as the operation and the maintenance cost of the water supply systems mainly come from the various mechanical systems and the pipeline systems of the collecting/treating/distributing facilities. This paper presents a cost classification scheme and a probabilistic life cycle cost analysis (PLCCA) model for public water supply systems. A value analysis (VA) procedure that is well suited for practical purposes is also presented. The presented probabilistic life cycle model and the value analysis procedure were applied to a real world project, and this case study is discussed in the paper. The model and the procedure presented in this study can greatly contribute to the value-oriented design alternative selection, the estimation of the maintenance cost, and the allocation of budget for water supply system construction projects.

• Korean Journal of Construction Engineering and Management
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• v.6 no.6 s.28
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• pp.115-123
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• 2005

Design of steel $bridge^{\circ}AEs$ temporary works has conducted relying on the experiences of engineers based on the previous similar projects. Consequently, there have been arguments against over-design of temporary bents to be required at the actual construction sites, and unnecessary design changes have been issued at the construction stage. In this study, we have developed an optimum design support system for temporary works of the steel bridge construction through establishing the database for the materials to be needed for implementation of temporary works. We've also improved the accuracy and efficiency of the works through the design optimization for temporary works, and contributed to reduce design changes as well as to utilize the design informations at the construction stage.

• Archives of design research
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• v.21
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• pp.1-12
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• 1997

This research is that it could use a theory from a .cognitive science, making a hypothesis to explain the thingking steps of designing, adapting the problem solving of the design from knowledge of a cognitive science, to meet the possiblity which it can be developed the new way of the thinking. Design is a field where it needs a complexity with hi-brain activities. And cognitive science is a science which it study human brain activities. However, it is also quite possible to bo adaped over all design by linking with design and cognitive science. I explaned the ideation of the thinking steps on this study by the knowledge of cognitive science, to observe to be possible. I found out the new ways of possibilities from design thinking process. It is a result that I've been interpretated the design process and the thinking process out of the theory of knowledge structure.

• Geotechnical Engineering
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• v.26 no.9
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• pp.33-47
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• 2010

Underground constructions continue to provide challenges to Geotechnical Engineers yet they pose the best opportunities for development and deployment of advance technologies for analysis, design and construction. The reason for this is that, by virtue of the nature of underground constructions, more data and information on ground characteristics and response become available as the construction progresses. However, due to several barriers, these data and information are rarely, if ever, utilized to modify and improve project design and construction during the construction stage. To enable the use of evolving realtime data and information, and adaptively modify and improve design and construction, the paper presents an analysis and design system, called AMADEUS, for underground projects. AMADEUS stands for Adaptive, real-time and geologic Mapping, Analysis and Design of Underground Space. AMADEUS relies on recent advances in IT (Information Technology), particularly in digital imaging, data management, visualization and computation to significantly improve analysis, design and construction of underground projects. Using IT and remote sensors, real-time data on geology and excavation response are gathered during the construction using non-intrusive techniques which do not require expensive and time-consuming monitoring. The real-time data are then used to update geological and geomechanical models of the excavation, and to determine the optimal, construction sequences and stages, and structural support. Virtual environment (VE) systems are employed to allow virtual walk-throughs inside an excavation, observe geologic conditions, perform virtual construction operations, and investigate stability of the excavation via computer simulation to steer the next stages of construction.

• Journal of the Korean Institute of Educational Facilities
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• v.14 no.4
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• pp.53-65
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• 2007

The present research has been conducted on the arranged form, the number and kinds, the area, the location of the rooms and the variation on exterior designs, based on a layout and a ground plan of each step, which are general plan, VE proposal and the final negotiation, for 11 elementary and middle and high schools that are designed in the way of BTL project. In consequence, it has been found out that there are some changes in the number and position of the rooms. However, the changes are not exceeding the overall arrangement form. This could not have led to the original aim, which is to induce creativity by PFI. It can be supposed that it is because the BTL system is stick to the old process, the method of financial investment and it is true to say that there needs to be solution for that.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1255-1261
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• 1995

The development of LCD Simulation program has been targeted to the design and estimation of LCD in an efficient, reasonable and proper method. In developing this program, we have got the theoretical construction for analysis of LCD. Moreover, we've applied CAE to the field of LCD, and thus we could help finding the optimal condition of LCD design or new type of LCD. This software can be applied for the modes such as TN, mono-STN, B/W STN(DSTN, FSTN), color STN, TFT, reflective modes and the program can be developed for other modes.

• The Journal of Sustainable Design and Educational Environment Research
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• v.3 no.2
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• pp.39-49
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• 2003

This study purpose is extract on the architectural principles and architectural planning direction for Integrated Secondary School. The integrated secondary school has an expectation of the total education environment in which has some problem as regional, teaching, treatment, establishment equipment part because of the based relative establishments are abolished. The expectations are the education effective rising, the reduce of the responsibility of the teacher, a smooth teacher placing and saving the educating estimate. As the new education course propulsion is raising the school and students discretion and expanding the way of educating, being close to the course of studies, the integrated operation is earnestly needed and such as these versatile background the small school will keep on getting integrated. Investigate about the senses of the manager and teachers, so after these reserch I've concluded these things below about the integrated secondary school.

• Korean Journal of Computational Design and Engineering
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• v.6 no.4
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• pp.236-243
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• 2001

A key factor far realizing the internet-based virtual manufacturing system(VMS) and virtual enter-prise(VE) is how to precisely and effectively represent the machine elements and mechanics. In this paper, we present methods to represent the numerically controlled machine tools in the internet environment. The method is composed of: 1) geometrical modeling of the machine tools, 2) kinematic modeling for the movements of the machine tools, and 3) representing the developed model in the internet infrastructure. Based on the models. a web-based virtual machine tools (WVMT) is developed, and it can be accessed at hrrp://wvmt.postech.ac.kr. The WVMT can be used for various purposes: 1) web-based virtual manufacturing system, 2) web-based CAM system, and 3) CNC educational tools for the vocational school through internet.

• Korean Journal of Computational Design and Engineering
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• v.14 no.6
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• pp.374-381
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• 2009

To meet the soaring demand recently, South Korea big shipbuilders are examining two things. One is new investment in plant and equipment. The other is replacement of production resources. Considering plant & equipment investment and replacement of production resources, even if actual production ability would be enough, the real output could be affected by limitation of logistics with lack of analysis. As we set up big shipyard in virtual space, we could perform actual production by using confirm production plan in virtual space. We've analyzed the load of block stock, load of road and load of transporter for logistics effects are followed by production increase. This research is to determine the possible problems of those analyzed results and to present the resolution using the current layout. And then modified yard layout, we reanalyzed previous three logistics effects. This simulation model could help administrator to make rational decision for changing yard layout.