• Journal of the Korea Safety Management & Science
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• v.16 no.2
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• pp.19-29
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• 2014

Korean societal concern for the train accidents is fast and widely increasing with an ever-increasing demand and use for KTX. Most of these train accidents are inclined to be caused by human error. Experts used to attribute the causes of human error to the defects in various aspects such as technology, organizational system, practices, corporate culture, and/or human resource itself. Among the diverse causes of human error, an important one, even though it was rarely focused, may be the issue of impact of rule or procedure change on human error. Giving attention to the implicit importance of this issue, this study intends to highlight the theme of frequent procedure change in railway driving manual as a critical factor of human error. To attain this purpose mentioned above, dual methodologies were adopted. One is to qualitatively analyze the real cases of procedure change in relevant manuals followed by the incident case(passing the station scheduled to stop) happened lately. Another is to quantitatively perform statistical analysis based on questionnaires received from 224 train drivers. Results show that frequent changes in internal affairs procedure is or may be an important factor causing stress and human error from train drivers.

• Membrane and Water Treatment
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• v.3 no.2
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• pp.113-121
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• 2012

Up-flow multi-layer bioreactor (UMBR) is a hybrid system using dual sludge that consists of an up-flow multi-layer bioreactor as anaerobic/anoxic suspended growth microorganisms followed by an aeration tank. The UMBR acts as a primary settling tank, anaerobic/anoxic reactor, thickener which requires low energy due to mixing by up-flow stream. This study focused on using a pilot UMBR plant with capacity of 20-30 $m^3$/day for domestic wastewater in HCMC. HRTs of UMBR and aeration tank were 4.8 h and 7.2 h, respectively. The average MLSS of UMBR ranged from 10,000-13,600 mg/l SS. Internal recycle rate and sludge return were 200-300% and 150-200%, respectively. The results obtained from this study at flow rate of 20 $m^3$/day showed that removal of COD, SS, TKN, N-$NH_4$, T-N, and color were 91%, 87%, 86%, 80%, 91% and 91%, respectively.

• Journal of Korean Home Economics Education Association
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• v.14 no.2
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• pp.1-14
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• 2002

The goal of the study is to find the necessary measures to facilitate a desirable Technology and Home Economics curriculum by reflecting the Perception and needs of the teachers from the perspective of the curriculum content. professionalism of the teacher realistic operations of the school . and the administration of the school system. The results obtained from the research are as follows : 1) The background knowledge and characteristics of the two curriculums are different. and in addition there is a negative perception due to the fact that it is hard to facilitate a class with just one teacher. 2) The issues that were most serious to teachers were professionalism of the teacher. qualification of the teachers. and teaching method. Also the teachers lacked in confidence in teaching and the curriculum itself. 3) In regards to qualifications of the teacher the teachers requested that teachers should have single qualification in 'Technology(or Home Economics)'or dual qualifications in both 'Technology' and 'Home Economics'. As for teaching methodology responded that from the teacher and student perspective the teaching should be divided whereas from the school's perspective the responsibility should be Put on a single teacher. 4) Teachers responded that from the perspective of the teacher, parent or student Technology and Home Economics should be separated into two subjects.

• Journal of the Korean Home Economics Association
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• v.46 no.1
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• pp.103-116
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• 2008

The purpose of this study was to empirically describe the everyday life of middle-aged adults in terms of their time-use activities. From the original '2004 Time dairy' Data, developed by the Korean National Statistical Office (KNOS), 17,684 respondents aged between 35-59 were selected. In order to categorize their activity patterns, work/labour, domestic labour, and spare leisure time were classified according to the action classification system. As a result, four dominant types were found: namely work-leisure, work-oriented, family-oriented, and leisure-oriented activities. Results of multinomial logistic analysis revealed that gender, age, socioeconomic status, job characteristic, and family structure were the major determinants on time-use. Compared with work-leisure, young middle aged women holding a part-time job with less income tended to be involved in a family-centered time use. Dual earners with lower SES status were likely to have work-oriented time schedules. Older men with relatively lower income were more likely to be involved in leisure-oriented activities rather than work-leisure activities. Multitasking behavior was a significant variable in explaining the four different types of time-use. Work-oriented group showed the highest level of time pressure as well as fatigue. Group differences in these measures, however, was not as large as expected.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.5
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• pp.1-9
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• 2004

The performance analysis code has been developed for vertical take-off and landing(VTOL) UAV which can be utilized as a trade analysis tool in the pre-conceptual design phase. The UAV requires VTOL capability and high speed cruise performance. The main logic of this performance analysis code is to estimate performance parameters of each mission segment by mission fuel weight iteration. The reliability of this performance analysis code is discussed by comparing the data of existing dual flight mode VTOL UAVs such as Boeing CRW and Bell Tilt Rotor.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.3
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• pp.103-111
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• 2012

Works for dam heightening plan have dual purposes: flood disaster prevention by securing additional storage volume and river ecosystem conservation by supplying stream maintenance flow. Now, the dam heightening project is in progress and there are 93 dam heightened reservoir. After the dam heightening project, 2.2 hundred million ton of flood control volume in reservoirs will be secured. Thus it is necessary to evaluate the effects of the dam heightening project on watershed hydrology and stream hydraulics, and resulting flood damages. This study was aimed to assess the impact of outflow from the dam heightened reservoir group on the Whangryong river design flood. The HEC-HMS (Hydrologic Engineering Center-Hydrologic Modeling System) model was used for estimating flood discharge, while HEC-5 (Hydrologic Engineering Center-5) was used for reservoir routing. This study analysed flood reduction effect on 100yr and 200yr return periods about the before and after heightening of agricultural dams. Based on the results of this study, the reduction of flood peak discharge at downstream of the reservoir group was estimated to be about 41% and 53% for 100yr and 200yr frequencies, respectively.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.3
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• pp.366-370
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• 2010

This paper presents an automatic Oriental ink-rendering technique that recreates the artistic style of Oriental paintings from a single image. In Oriental paintings are characterized by strokes with various thickness and disordered dispersion. In this study, a stroke drawing method was developed based on the canny edge detector and radial curvature that are suitable for lines with varied thickness even along a single stroke. A dispersion-shading method was likewise developed by applying a set of iterated dual-filtering, and intensity exaggeration methods. The dispersion-shading method is designed to increase the local shade details, to decrease the global shade. Unlike the existing watercolor-rendering and abstraction system the proposed dispersion-shading method achieves disordered shade details rather than simplification.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.06a
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• pp.181-182
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• 2009

In the machinery, the brake system is as important part as machine's working. If the machine doesn't stopped, would be big occident. For the ships, it is important too. Use the windlass winch to stop the voyage and use mooring winch to keep the stop in the port. In this study, improve the braking power divided the brake band and search the optimize portion.

• Journal of Practical Engineering Education
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• v.8 no.2
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• pp.75-81
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• 2016

This research proposes to design a flipped classroom with strategic questioning to enhance engineering student's creative problem-solving competency on the basis of the subject knowledge. By applying the designed flipped classroom to both of college and dual system engineering courses during one semester, this study explores to find the meaning and effects of the flipped learning method. The case study analyzed the influences of the flipped learning with the use of strategic questioning on student's problem-solving performance, and also investigated student satisfaction and evaluation of the learning in order to draw out the factors to consider further in the instructional design.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.60-61
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• 2007

IAZO (indium aluminium zinc oxide) anode films were co-sputtered on glass substrate using a dual target DC magnetron sputtering system. For preparation of IATO films, at constant DC power of IZO (indium zinc oxide) target of 100 W, the DC power of AZO (Aluminum zinc oxide) target was varied from 0 to 100 W. To analyze electrical and optical properties of IAZO anode, Hall measurement examination and UV/V is spectrometer were performed, respectively. In addition, structure of IAZO anode film was examined by X-ray diffraction (XRD) method. Surface smoothness was investigated by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). From co-sputtered IAZO anode, good conductivity($2.32{\times}10^{-4}{\Omega}.cm$) and high transparency(approximately 80%) in the visible range were obtained even at low temperature deposition. Finally, J-V-L characteristics of phosphorescent OLED with IAZO anode were studied by Keithley 2400 and compared with phosphorescent OLED with conventional ITO anode.