• Journal of the Korean Society of Safety
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• v.19 no.4 s.68
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• pp.42-47
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• 2004

In this paper, we analyzed on the characteristics of the stranded wire disconnected by repeated stress. The stranded wires that were used in the experiment are PVC insulated flexible cords(VCTFK: Vinyl Insulated Vinyl Cabtyre Cord Flat-type) of $0.75mm^2,\;1.25mm^2,\;and\;2.0mm^2$. They are used to connect the load in low voltage. The stranded wires disconnected by repeated stress were magnified with optical microscope. Using X-ray, the disconnected wire were photo-graphed. we compared mechanical characteristics of the stranded wire between disconnected tendency and allowable current. On the mechanical strength of vinyl cap tire ellipse type cords under bending stress, VCTFK of $1.25mm^2$ was the strongest of them. When it was bent $826.3\pm7$ times, it appeared the disconnected tendency that element wires of VCTFK of $1.25mm^2$ are more about 1.67 times than element wires of VCTFK of $0.75mm^2$. In mechanical strength, VCTFK of $1.25mm^2$ is higher about 1.7 times than VCTFK of $0.75mm^2$. Therefore, we found out that mechanical strength was higher, when the wire had a lot of element wires. In comparison with bending stress, VCTFK of $1.25mm^2$ is the strongest among samples, and it is the most useful in wires of movable type.

• New & Renewable Energy
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• v.9 no.1
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• pp.60-68
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• 2013

In recent years, green house effect related natural disasters occur throughout the world. Carbon dioxide, mainly comes from the fossil fuel burning, is suspected to be the cause of green house effect. To reduce the emission of carbon dioxide, we need to find alternative energy resources such as photovoltaic energy. In this paper, the basic characteristics of wind force coefficient on a PV panel installed on the floating type PV energy generation system are investigated though the two-dimensional wind tunnel tests. Test variables included the angle of PV panel, direction of wind, number of rows of PV panel and attached or not attached frame. Based on the results obtained through the wind tunnel tests, it was found that the wind force coefficient can be used as a preliminary data in the design of the structure.

• KIEAE Journal
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• v.7 no.6
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• pp.17-22
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• 2007

The integration of PV modules into building facades or roof could raise their temperature that results in the reduction of PV system's electrical power generation. Hot air can be extracted from the space between PV modules and building envelope, and used for heating in buildings. The extraction of hot air from the space will enhance the performance of BIPV systems. The solar collector utilizing these two aspects is called PV/T(photovoltaic/thermal) solar collector. This paper compares the experimental performance of two different types of air type PV/T collector units: the base case of a collector unit with 10cm gap for forced ventilation and the other unit with copper pin attached to PV module to enhance its thermal performance. The experimental results shows that the base case unit had the overall efficiency of 41.9% and the improved unit with copper pin attached to PV module had 50.1% efficiency. For these air type PV/T units, the forced ventilation of the air space improved the electrical performance as well as the thermal performance.

• The Journal of the Korea Contents Association
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• v.21 no.2
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• pp.520-527
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• 2021

In this study, we focused on the low practicality of traditional outdoor advertisements due to uniformity of materials, shapes, and designs, so in order to improve it, we will analyze impact on the practicality of outdoor advertisements depends on the attached type of advertising signboards. The research method is to set up a research model and hypotheses through a literature review and conduct a survey and then perform factor analysis and hierarchical regression analysis. Hypothesis1. The evaluation factors (readability, formability or symbolism) of outdoor advertising signboard in traditional markets will affect their practicality. Hypothesis 2. The type of attached advertising signboards (protruding type or wall-type) in traditional markets will control the impact of each evaluation factors' on practicality. In a result, readability and formability will affect practicality. To increase practicality, the size, color, font, layout and etc. of outdoor advertising signboards should be well recognized to get the better understanding. Also, practicality will be increased by the harmonization and the sense of balance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.8
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• pp.635-639
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• 2013

Generating output characteristics of a EYE-type piezoelectric generator depending on ceramic size and materials of the elastic body were studied. EYE-type piezoelectric-generating device consist of the ceramic was attached between the both elastic body. piezoelectric-generating is that if the tension occurred at both ends of an elastic body, the piezoelectric effect occurs at ceramics through the form change of the elastic body. The structure of this EYE-type generator use various area. than a existing type generator, because the ceramic position of the directly force at does not apply. Resonance and output characteristics of the generator were analyzed by using FEM program. Generators were fabricated on the basis of analyzed results and attached on a frequency controllable vibrator to measure output characteristics. Also, the experimental results were compared with the simulated results. As a result, output characteristics of the generator increased depending on the increase in ceramic thickness. In case of increase in ceramic width, resonance frequency of the generator also decreased.

• Journal of Korean society of Dental Hygiene
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• v.11 no.4
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• pp.465-474
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• 2011

Objectives : The removal of most reliable mechanical dental plaque that is to say tooth brushing was generalized to control of dental plaque, many oral health goods have also developed due to the effect differences followed by individual habit. The electric toothbrush have studied and developed widely as major field of study that electric toothbrush having various moving phase was sold and developed at the market. Methods : Accordingly author studied about selling electric toothbrushes shape (vibration type, ultra-sonic minuteness vibration type, semi rotation type) to raise the efficiency after comparing to the moving them that total 8 groups classified by poor tooth models for example normal set of tooth, crowding tooth, bracket attached tooth, prosthetic status etc. and executed plaque removal effect on the tooth through comparing experiment. Results : The removal rate of artificial plaque on the tooth was improved in proportion to the increase of tooth brushing time(p<0.05). The ultra-sonic minuteness vibration and semi rotation type was superior to toothbrush of vibration type comparing to the removal rate of plaque on the tooth(p<0.05). Conclusions : The electric toothbrush of supersonic minuteness vibration and semi rotation type can be recommended most of tooth types regardless of oral tooth setting status for example, normal set of tooth, crowding tooth, bracket attached tooth, porcelain tooth.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.2
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• pp.299-305
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• 2013

Physical One-way Transfer, one of network Separating Network Technologies, shut off intrusion possibilities by removing data transfer line from external network to internal network. Physical One-way Transfer technology can not support legacy services based duplex transmission. Legacy services operating need agent for extra service with the support. But, Agent development have problems with adding cost and open internal protocols. In this papers, We analyzed legacy services between Control network and OA network in working SCADA systems, and based on the results obtained from the analysis, categorized the legacy services into three forms. We propose an agent generation method of the three service categories for Physical One-Way Transfer System. In addition, we design an automatic generation tool using the proposed method.

• Journal of the Korean housing association
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• v.14 no.6
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• pp.205-214
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• 2003

The purpose of this study is to investigate the characteristics of the floor plan of single detached houses in Canada. A quantitative & qualitative analysis method of th 260 house plan was used in this study. The followings were found out from this analysis : 1) There were the differences of the lay-out and the number of public spaces between a small type and a big type. 2) There were the differences of the equipment and the number of bathroom between a small type and a big type. 3) The most work center type of kitchen was 'ㄴ+ㅁ' type(33%). 4) The most type of floor plan was that one with attached garage(87%) and center entry(99%). 5) Almost floor plans having 3 or 4 bed rooms even though medium II and large size plans which is to show that the basic needs of family life rely on the omnifarious public spaces.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2292-2297
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• 2008

Recently, a study on condensers for refrigerators has focused on new model which will cost less and will be more efficient. Some widely used condensers for domestic refrigerators are wire-and-tube type condenser, hot-wall type condenser, and spiral type condenser. Some companies which use the spiral type condenser at the moment try to develop a new type condenser which will cost less and will be as efficient as the spiral type. The new type condenser consists of a steel tube, steel plates and louver fins attached to the tube. The tube and the plate are bent into a single-passage serpentine shape.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.227-233
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• 2002

For the purpose of high outlet pressure, compactness and low vibration and noise, modem reciprocating air compressors are tend to have a multi-stage W-type or V-type cylinder arrangement. An effective counter weight calculation method is presented for reducing the inertia forces of the compressor. This calculation method is using the complex representation and verified its validity. A design program for the counter weight of W-type or V-type air compressor was presented to the manufacturer, A designed counter weight was attached to the W-type or V-type air compressor. Vibration test results gave us improved performance.