• Journal of the Korea Concrete Institute
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• v.16 no.1 s.79
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• pp.10-17
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• 2004

Shear tests were performed on four ends of full scale U-type beams which were designed by optimum process for the depth with a live load of 4903Pa. The ratio of width to depth of full scale 10.5 m-span, composite U-type beams with topping concrete was greater than 2. Following conclusions were obtained from the evaluation on the shear performance of these precast prestressed beams. 1) Those composite U-type beams performed homogeneously up to the failure load, and conformed to ACI Strength design methods in shear and flexural behaviors. 2) The anchorage requirements on development length of strand In the ACI Provisions preyed to be a standard to determine a failure pattern within the limited test results of the shallow U-type beams. 3) Those all shear crackings developed from the end of the beams did not lead to anchorage failure. However, initiated strand slip may leads the bond failure by increasing the size of diagonal shear crackings. 4) The flexural mild reinforcement around the vertical center of beam section was effective for developments of a ductile failure.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.589-592
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• 2011

In this paper, bidirectional DC-DC converter is designed to cover up defects of fuel cell generating system like as low dynamic characteristic, unstable output and lack of storage ability by using bidirectional DC-DC Converter and supercapacitor that available to charge & discharge quickly, high efficient at charge & discharge and semi-permanent. Operating efficiency has been analyzed through simulation and examination. According to these design and data, hybrid system has been made and operation test, evaluation and results evaluation have been performed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.4
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• pp.163-172
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• 2017

In recent days, the Non-Linear Editing is mainly used in the field of broadcasting. In comparison to conventional editing, Non-Linear Editing can immediately access the image of the desired position and facilitate the insertion and deletion of video frame. Furthermore, it directly apply a title and transition effect to video frame. Moreover, it has an advantage of preview and easy modification in title effect, transition and editing prior to export. However, students who learn Non-Linear Editing first time are not easy to learn it. In this paper, we propose a new learning model based on Reciprocal Peer Teaching (RPT), which helps NLE beginners to understand Non-Linear editing more clearly. We divide the students into two groups i.e. control group and experimental group. The control group students do not apply proposed method while experimental group performs evaluation over our model. Furthermore, we carry out the experiments, which include the overall average of the two groups, academic achievement of students with low grades, standard deviation, T-test and satisfaction surveys. The experimental group shows the superiority in performed experiments and higher satisfaction ratings than the control group.

• Journal of Power System Engineering
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• v.14 no.4
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• pp.63-67
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• 2010

This paper introduces the eddy current signal characteristic of magnetic and non-magnetic gas turbine rotor. In the past, Magnetic particle inspection method was used in magnetic material for qualitative defect evaluation and the ultrasonic test method was used for quantitative evaluation. Nowadays, eddy current method is used in magnetic gas turbine rotor inspection due to advanced sensor design technology. We are studying on the magnetic gas turbine rotor by using eddy current method. We prepared diverse depth specimens made by magnetic and non-magnetic materials. We select optimum frequency according to material standard penetration data and experiment results. We got the signal on magnetic and non-magnetic material about 0.2 mm, 05 mm, 1.0 mm, 1.5 mm 2.0 mm and 2.5 mm depth defects and compare the signal amplitude and signal trend according to defect depth and frequency. The results show that signal amplitudes of magnetic are bigger than non-magnetic material and the trends are similar on every defect depth and frequency. The detection and resolution capabilities of eddy current are more effective in magnetic material than in non-magnetic materials. So, the eddy current method is effective inspection method on magnetic gas turbine rotor. And it has the merits of time saving and simple procedure by elimination of the ultrasonic inspection in traditional inspection method.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.1
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• pp.13-20
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• 2006

This study proposes a new concept of a tunnel central drainage system by using a drain board to make a breakthrough on difficulties in the installation of conventional drainage system and draw-down of its drain capacity especially in long tunnels. A fundamental study has been performed for evaluation of the drain capacity of the planar drainage system adopted in this study. In fact, the system proposed makes possible to omit the side, transverse as well as central drainage pipes required in the conventional system, even if its drain capacity and any guideline for design are not available to date. In this circumstance, it is carried out to investigate the correlation between drain capacities and, shapes and posit ions of the columns of the drain board in terms of a variety of water inflows through hydrological model tests. It is shown from the tests that a drain capacity is highly influenced by the shape and the distance between the columns of a drain board in flowing direction, and a round rectangular shape of the columns leads to the highest capacity of drainage. And also, the shorter distance between the columns in flowing direction, the higher drain capacity would be achieved.

• Journal of the Ergonomics Society of Korea
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• v.26 no.4
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• pp.65-73
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• 2007

This study evaluated the short message service (SMS) and multimedia message service (MMS) usability of mobile phones and wireless internet services by performance failure rates and flowcharts that adopted the concept of state diagrams. Forty-eight participants who had an experience of using mobile phones were recruited by posting an advertisement on websites for the experiment. They carried out both SMS and MMS tasks with the mobile phones of LG Cyon and Samsung Anycall as well as the wireless internet services of LGT ez-i, KTF magicN, and SKT NATE. In general, Cyon had the lower performance failure rate than Anycall for SMS, and ez-i had the lowest performance failure rate than the other services for MMS. More specifically through the workflow analysis, most participants used hot keys to take 7-8 steps to send a SMS including a symbol and had a difficulty in typing the symbol. They also took 10-11 steps to send a MMS after taking and attaching two pictures. Anycall, magicN, and NATE had significantly large error and failure rates due to the limited option of the menu paths that users could take and poor compatibilities of menu names and between menu and navigation keys. This study showed the possibility of use of flowcharts for systematic and specific usability evaluation methods and found the causes of performance errors and failures with mobile phones and wireless internet services to provide insight into their design.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.8
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• pp.1001-1010
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• 1998

The purpose of this study was to investigate the images and characteristic formative elements of Korean traditional patterns. The Korean pattern image could be interpreted into visual elements of design based on the images, the characteristic formative elements of Korean traditional patterns, and their relationships. Fourteen patterns selected from 5 groups of Korean patterns were used as stimuli. An image evaluation using a 2-point sementica scale of 19 bipolar adjectives, and an impression evaluation of which results were presented by visual drawing using lines and shapes were carried out. The data were analyzed by correspondence analysis and cluster analysis. The major findings are as follows; 1. Fourteen patterns and 19 adjectives were marked on a perception map composed of two (x and y-) axes. The bipoles of x- and y axes were soft-hard and splendid-artless, respectively. 2. Four clusters semerged to account for the dimensional sturucture of 14 patterns and 19 adjectives. These were splendid image, soft image, individualistic image, and sophisticated image. However there was no pattern which belonged to the cluster, sophisticated image. The Korean pattern image was founded to be better related to the kind of patterns than the type of patterns. 3. The characteristic formative elements obtained from the impression test were contour of motif, repeated line or shape, various curved lines, and decorative elements. 4. The splendid image was related to Bongwhang patterns and detailed line and complexity. The individualistic image was related to the abstractive form of Bongwhang pattern and the decorative form of Cloud pattern both of which have the characteristics of point-symmetry and abstraction, and Turtle-back pattern. In this case, the related charac-teristic formative element was identified to be repeated lines. The soft image was related to Moran, Cloud, and Taegeuk patterns. The related characteristic elements were various types of curved lines, decorative elements, and rounded contours.

• Journal of Environmental Impact Assessment
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• v.22 no.6
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• pp.581-589
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• 2013

Generally, Sewage Treatment Plants(STPs) are complexes systems in which a range of physical, chemical and biological processes occur. However, their performance strongly depends on the know-how acquired by the field-engineer. Recently, in order to solve this situations, various operation and management technologies based on the Instrumentation, Control and Automation(ICA) have been developed. As a economies-environmental affect point of view, this study was for the performance evaluation and assessment of results from the Smart Operation System(SOS) in full-scale STP. The SOS in STP consisted of the process monitoring module, including real-time influent prediction and effluent simulation, and the Smart Air Control(SAC) module. According to the results from field test for 2 years, the results of economical evaluation, amount of benefits and cost saving by the SOS have shown to be much higher than that of traditional operation. Nevertheless, the removal load(kg/yr) of BOD 13.3 %, COD 28.2 %, TN 44.4 % and TP 20.8 % were increased, respectively. Remarkable improvement of removal load could be achieved after the SOS was adapted. It was concerned that the SOS offer a user friendly functionalities and cost saving needed by the field-engineers. In addition, it was expected that the results of this study would supply helpful information for design and cost saving for the SOS in full-scale STP.

• Fashion & Textile Research Journal
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• v.13 no.4
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• pp.614-623
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• 2011

The purpose of this study is to develop a wedding dress basic torso pattern and sleeve pattern considering good fit and aesthetic for figures of Korean brides in their 20s. For the research method, 3 women in their 20s who has the body size of ${\pm}$ S.D range of average figure and dress form suggested by 'the 5th human body measurement' of Size Korea were selected as the test group. The evaluators are 8 clothing construction majors, and the evaluation items included total 22 questions related to torso and total 10 questions related to sleeves. The evaluation was made using 5 Likert point scale. 4 prototypes for basic dress pattern were selected through the literature search. After compare analyzing design methods of prototypes, the real wedding dresses were made in the average size of women in their 20s and the dresses were tried on for the assessment. The data was analyzed using SPSS 18.0 Program to examine average, standard deviation and significant differences between basic patterns. Based on the results of the first and the second try-on assessments, a new wedding dress basic pattern with maximized strengths of compared prototypes was completed. The details of result follows. As for dress torso basic pattern, A pattern, which had the highest overall silhouette satisfaction and scores in basic pattern analysis and try-on assessments, was selected as the prototype, and a research basic pattern reflecting strengths of each basic pattern was developed. As for dress sleeve basic pattern, B pattern, which had the highest overall silhouette satisfaction and scores in basic pattern analysis and try-on assessments, was selected as the prototype, and a research basic pattern reflecting strengths of each basic pattern was developed. In this study, a wedding dress basic pattern considering good fit and aesthetic for figures of Korean brides in their 20s was suggested. It is expected that the basic pattern will be used by continuously developing dress market and ready-made wedding dress manufacturers as well as in educational institutes.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.10
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• pp.79-88
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• 2003

The paper presented here covers the work associated with the flight control law design, ground based and in flight simulation and handling qualities assessment of the Fly-by-Wire type Aircraft (FBWA). The FBWA configurations are of the same generic form of the Korean advanced trainer. The normal acceleration (Nz) and pitch rate (q) feedback control system is employed for longitudinal axis and roll rate (p) and lateral acceleration (Ny) feedback flight control law is developed in lateral/ directional axis. The flight tests for the FBW A dynamics evaluation were executed for the target aircraft (FBWA) on the IFS (In-Flight-Simulator) aircraft . The test results showed that Level 1 handling qualities for the most unstable flight regime and Level 1/2 for the landing approach flight regime were achieved. And the designed FBWA flight control law has revealed acceptable CHR (Cooper-Harper handling qualities Ratings).