• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.688-692
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• 2007

Solar thermal power generation allows additional benefits of cheap thermal storage and easy hybridization with other fossil fuel-driven power generation. KIER has been performing the project for solar thermal chemical reaction hybrid power generation. The project is to build and operate the first solar thermal chemical reaction hybrid power generation system in Korea. For concentrating solar thermal energy $m^2$ dish type concentrator was adapted and a heliostat is installed for reflecting horizontal insolation to the dish concentrator. At the moment building the dish concentrator including mirror and heliostat with sun tracking system was completed and it's performance are being closely evaluated. This paper will introduce some detailed designs and construction procedures which we have experienced so far.

• Journal of Periodontal and Implant Science
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• v.52 no.5
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• pp.411-421
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• 2022

Purpose: In this study, we aimed to evaluate the degree of heat generation when a novel drill design with an irrigation slot was used with metal sleeve-free (MF) and metal sleeve-incorporated (MI) surgical guides in an environment similar to that of the actual oral cavity. Methods: A typodont with a missing mandibular right first molar and 21 bovine rib blocks were used. Three-dimensional-printed MF and MI surgical guides, designed for the placement of internal tapered implant fixtures, were used with slot and non-slot drills. The following groups were compared: group 1, MI surgical guide with slot drill; group 2, MI surgical guide with a non-slot drill; and group 3, MF surgical guide with a slot drill. A constant-temperature water bath at 36℃ was used. The drilling was performed in 6 stages, and the initial, highest, and lowest temperatures of the cortical bone were measured at each stage using a non-contact infrared thermometer. Results: There were no temperature increases above the initial temperature in any drilling procedure. The only significant difference between the non-slot and slot groups was observed with the use of the first drill in the MI group, with a higher temperature in the non-slot group (P=0.012). When the heat generation during the first and the second drilling was compared in the non-slot group, the heat generation during the first drilling was significantly higher (P<0.001), and there was no significant difference in heat generation between the drills in the slot group. Conclusions: Within the limitations of this study, implant-site preparation with the surgical guide showed no critical increase in the temperature of the cortical bone, regardless of whether there was a slot in the drill. In particular, the slotted drill had a cooling effect during the initial drilling.

• International Journal of Contents
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• v.18 no.1
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• pp.76-84
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• 2022

Tidal power generation plays a critical role in reducing greenhouse gas emissions. It uses a tidal force generated by gravitational force between the moon, the earth, and the sun. The change of seawater height generates the tide-generating force, and the magnitude of the change is the tide level. The tide level change has the same period as the tide-generating force twice a day, every 29.5 days, every year, and every 18.6 years. Sihwa Lake Tidal Power Station is Korea's first tidal power plant that began commercial power generation in August 2011 and has been accumulating a large volume of data on electricity production, power generation sales, sluice displacement, and tide levels. The purpose of this paper was to analyze the impact of the inefficiency factors affecting production and the tidal level change on tidal power generation and their characteristics using Sihwa Lake Tidal Power's operational performance data. Throughout this paper we show that tidal power generating operation is accurately predicting the trends of magnitude of tidal force to be periodical for each day. determining the drop to initiate the water turbine generator factoring the constraints on the operation of Sihwa Lake, and reflecting the water discharge through the floodgate and water turbine during the standby mode in the power generation plan to be in the optimal condition until the initiation of the next power generation can maximize power generation.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.10
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• pp.121-129
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• 1995

The objective of this research is to develop an effective inspection planning strategy for sculptured surfaces by using 3-dimensional Coordinate Measuring Machine (CMM). First, the CAD/CAM database is generated by using the Bezier surface patch mathod and variable cutter step size approach for design and machining of the workpiece model. Then, optimum measuring point locations are determained based on the mean curvature analysis to obtain more effective inspection results for the given sample numbers. An optimal probe sequence generation method is proposed by implementing the Traveling Salesperson (TSP) algorithm and new guide point selection methods are suggested based on the concepts of the variable distance between the first and second guide points. Finally, simulation study and experimental work show the effectiveness of the proposed strategy.

• Journal of Korea Technology Innovation Society
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• v.8 no.3
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• pp.1005-1026
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• 2005

On the contrary to the expansion of feasibility studies on public construction and development projects, there is few feasibility studies on S&T, especially large-scale basic research facilities. Based on this critical mind, we tried the first feasibility study on large-scale basic research facilities, that is, the 4th Generation Light Source. First, it is validated whether the construction of 4th Generation Light Source is economically feasible and second, if economically feasible, the optimal place and time for construction are analyzed by using Analytical Hierarchy Process. This research shows that the construction is economically feasible irregardless of scenarios on future bio-medicine industry growth and to construct at Pohang in 2006 is optimal strategy. On the basis of this analysis, the feasibility studies on large-scale basic research facilities are expected to be more expanded and developed.

• Journal of The Korean Digital Architecture Interior Association
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• v.12 no.3
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• pp.5-13
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• 2012

In this study, features and design effects of PV(Photovoltaic) modules were classified to help the installation of BIPV(Building Integrated Photovoltaic) In addition, through domestic and international trends and cases survey, installation method was organized and applicable range of efficiency and design from First-generation solar cells to the third-generation solar cell was classified. Frist, Crystalline Solar cell module of first-generation is appropriate for the wall type, roof, louver, shading and etc. It has superiority of technology and price stability and can be achieved by a variety of aesthetic effects. Second, Dye-Sensitized Solar Cell of Thin Film solar cell can express a variety of colors, adjust light transmittance and maximize the aesthetic splendor. It is appropriate for the wall type, window type, curtain wall type and etc. Also, see-through type solar cell can provide comforts cause of free flow of light. And it is advantageous from economic due to adjust the indoor temperature. It is appropriate for the atrium type, curtain wall type, window type and etc.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.6
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• pp.145-153
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• 1995

An algorithm for the automatic generation of quadrilateral shell elements on three-dimensional sculptured surfaces has been developed, which is one of the key issues in the finite element analysis of structures with complex shapes such as automobile structures. Mesh generation on sculptured surfaces is performed in three steps. First a sculptured surface is transformed to a projection plane, on which the loops are subdivided into subloops by using the best split lines, and with the use of 6-node/8-node loop operators and a layer operator, quadrilateral finite elements are constructed on this plane. Finally, the constructed mesh is transformed back to the original sculptured surfaces. The proposed mesh generation scheme is suited for the generation of non-uniform meshes so that it can be effectively used when the desired mesh density is available. Sample meshes are presented to demonstrate the versatility of the algorithm.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.04b
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• pp.357-364
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• 2000

The three main processes involved in the design of stressed membrane surface are surface form-finding, stress analysis and cutting pattern generation. The last process, cutting pattern generation, is considered as a very important procedure in the aspect of the practical design for the fabric membrane surface. In this paper, The cutting pattern generation technique using the geodesic line algorithms is first introduced. And the numerical examples resulting from this technique are presented. Cable elements are used for the approximating membrane surface and two kinds of model, square line and central line model, are used in pattern generation. Finally, a number of different cutting pattern generation for the same membrane surface is carried out and the numerical results are compared each

• Journal of the Korean Home Economics Association
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• v.37 no.9
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• pp.85-101
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• 1999

The purpose of this study is to investigate how much traditional family ethics exist in morden society. For this goal, I have analyzed norm consciousness of the family among adolescent, middle and old generation. In this research, three kinds of questionnaire were used and the data were obtained from 1,661 samples of three generation groups living in Gyengnam area. The major findings obtained from this study are as follows: First, the filial piety and consciousness for supporting their parents were not changed at all in traditional family ethics. The filial piety and consciousness for supporting their parents are the most important family concepts without showing any difference in generation-gap in modem society. Second, the decreasing traditional norm consciousness of family was familism value. Specialty the familism value becomes weaker from old to younger generation. Third, the filial piety and familism value were shown to be the important factors to support their parents. These concepts showed same trends without showing generation-gap.

• Journal of Sericultural and Entomological Science
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• v.23 no.1
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• pp.32-37
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• 1981

It is necessary to improve new silkworm variety suitable for the artificial diet different from the mulberry leaves in physical and chemical natures. The silkworms fed on artificial diet show low productivity in general. So the effectiveness of selection for cocoon characters was studied when the silkworms were reared on the artificial diet for several generations. The results obtained are as fellows: 1. There is no correlation between the cocoon shell weight and the cocoon shell percentage in female cocoons of both Sa and Y strains but in male cocoons. 2. No correlation exists between the weight of a cocoon and a cocoon shell percentage of male cocoons in Sa strain. 3. There is a specific effect of the artificial diet on selection between Japanese and Chinese strains compared with the mulberry leave rearing. 4. The cocoon quality of first generation in artificial diet rearing was very inferier to that of previous generation in mulberry leave rearing in both Sa and Y strains, but the effect of selection rapidly increased in first and second generation.5. Very high mortality was noted in 4th generation to the degree of hardness for successive generation. 6. From 6th generation to 10th generation, the effectiveness of selection for cocoon characters increased continuously except the cocoon shell percteage.