• The Journal of Natural Sciences
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• v.9 no.1
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• pp.9-17
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• 1997

We studied on the decoloring efficiency of a dying and finishing industrial wastewater containing reactive dyes in the ozone treatment system. The wastewater containing reactive dyes improved the decolorization by the ozone oxidation. In order to determine the optical conditions for ozonation, various operation factors such as initial wastewater concentrations, pH, temperature, and ozone dose were evaluated. Ozone utilization rate was improved in general with the increase of initial concentration of wastewater. And the decolorization speed or reactive dyes was more decreased in deep color of blue series than in light color such as yellow series. The colorization of wastewater containing reactive dyes was changed step through midle color depending upon increasing of ozone treated time. The efficiency of decolorization for wastewater was improved with the pH increased and the temperature of ozone treatment system decreased.

• Journal of Engineering Education Research
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• v.20 no.3
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• pp.32-41
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• 2017

The $4^{th}$ industrial revolution refers to an era where machines capable of outperforming humans are created. In light of the 4th industrial revolution, university students are demanded problem solving abilities, critical thinking abilities, and problem discovering abilities as general and basic abilities. The need for changes in the university level communication education for engineering students remains imperative in this constantly changing social environment. The era where education is conducted only in classrooms is over. This paper discusses the need for diversified education such as the integration of online and offline education, the reinforcement of learning outside of the classroom as well as an education model that transcends formal and informal education such as games and activities that induce self-learning, both intentional and non-intentional learning, and the utilization of mass media and social networking systems. Through providing an education model that assesses and utilizes the data gained from the learning process provided above, this paper widens the perception of future education methods in the 4th industrial revolution.

• Journal of the Korea Furniture Society
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• v.24 no.4
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• pp.345-349
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• 2013

Yellow poplar is well known commercial hardwood species in the world because of its availability, rapid growth, large size, excellent form, early natural pruning, and the good working quality of the wood. Therefore, yellow poplar (Liriodendron tulipifera L.) has been adopted in South Korea for decades ago, and its cultivating the saplings and silvicultural system have been studied. However, yellow poplar is still embroiled in controversy for utilization of use and worth. This species has not only advantages such as lower weight, light color, and higher machinability and bending processing, but also has disadvantages which are bad smell and different colors on heartwood and sapwood. In this study, the objective was that use of yellow poplar board as furniture materials by drying and painting process. Thirty years old yellow poplar was cut and dried for 7 days by high-frequency dryness. Adjustment of color tone to walnut color was conducted with multiple colorants and various number of spread times. Uniform color of yellow poplar on heartwood and sapwood was accomplished by applying 1 time stain (green), 2 times transparent primer, 1 time middle-painting (walnut), and 2 times top-painting (walnut) in sequentially. The painted yellow poplar board was used to manufacture table and dressing table. During the furniture manufacture process, no critical issues were occurred on part of jointing and painting. This painting method may be useful data for future use of yellow poplar as furniture materials.

• The Journal of Korean Association of Computer Education
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• v.16 no.3
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• pp.71-78
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• 2013

Internet ethics has been simply recognized as moral understanding, knowledge of etiquette or a kind of common sense. Recently, however, rapid growth of internet dysfunction such as the inadvertent disclosure of personal information, infringement of copyright and malicious code with hacking, has unavoidably broadened the territory of internet ethics. In this light, education contents of internet ethics must include not only laws and systems but specialized knowledge on prevention and action of internet dysfunction. In this paper, we analyze the variables affecting the educational achievement on diverse domains of internet ethics by investigating internet ethics qualifying examination and afterward we suggest some application methods to strengthen the internet ethics.

• Journal of IKEEE
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• v.22 no.3
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• pp.767-773
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• 2018

This paper proposes the simple structure LED-driving power converter with high power factor. As the proposed power converter combines the PFC boost converter and the conventional flyback converter into only one power conversion circuit, it simplifies the structure of LED-driving power converter. Thus the proposed converter is controlled using only one PWM controller IC, and it achieves high power factor, constant output voltage/current and cost-effectiveness. Therefore the proposed converter is suitable for the industry production and utilization of LED-light-system. In this paper, the operation analysis and design example of the proposed converter are explained, briefly. Also experimental results of the prototype that is implemented based on the designed circuit parameters are shown to validate operation characteristics of the proposed converter.

• Korean Institute of Interior Design Journal
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• v.13 no.5
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• pp.114-124
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• 2004

Most previous studies, in general, related to housing needs have analyzed the data from self-administered survey or interview using questionnaire or simple 2D floor plan. This study was Intended to suggest how to increase the reliability and effectiveness of such survey methods in examining the residents' housing needs. In order to accomplish the purpose, the two kinds of surveys using Web based VR media and typical questionnaire were peformed. The same questions were used for these two surveys, and they included the furniture characteristics, use of each room, adjustment of room size, preferences for interior colors, preferred furniture in living room, space layout of floor plan, housing life style, and preference for housing characteristics. The answer differences between these two were analyzed. The subjects were 402 housewives who lived in apartment houses in Haeundae, Busan. Finding were as follows: first, the media method was more likely to be effective than typical questionnaire survey in explaining housing needs for the adjustment of room size in housing unit plan. Second, the media method was more realistic and reliable than the other in comprehending the needs for the interior colors. Last, the VR media tended to be more effective than the other in understanding the space layout of floor plan. This research sheds light on the utilization of visual instrument for the analysis of needs related to space use.

• KIEAE Journal
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• v.6 no.4
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• pp.11-16
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• 2006

This work has carried out some preliminary studies for the utilization of a solar mini-dish system capable of concentrating solar rays to higher densities. A typical mini-dish system considered employs an array of solar mini-dishes where major components are light and compact. It consists of small mini-dishes, optical fiber bundles and diffusers at the end. Each mini-dish (typically has a 20 to 30 cm in diameter) is designed with a simple parabolic profile, concentrating sunlight (after the glass glazing cover to avoid dust deposition on the reflector and facilitate cleaning) onto a centrally-located small mirror which is placed on the bottom side of the transparent glass cover. The focused sunlight is reflected by the mirror surface onto a focal point where the receiving aperture of a homogenizer is located. Optical fibers are used to carry high-density solar rays to the other end where diffusers are mounted for indoor illumination. The proposed high density mini-dish system could make an efficient daylighting system as it excludes large moving parts and expandable if necessary. Each component of the system could be made from the off-the-shelf technology and thus, make the generic unit inexpensive to manufacture. Depending on spatial demand or characteristics, the amount of introducing daylight could be controlled. Preliminary tests have been carried out for a trial system to check any functional problems when in operation. Suggestions are also made to improve the design enhancing its performance and applicability.

• Smart Structures and Systems
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• v.1 no.4
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• pp.325-338
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• 2005

Utilizing robotic based reconfigurable nodal structural health monitoring systems has many advantages over static or human positioned sensor systems. However, creating a robot capable of traversing a variety of civil infrastructures is a difficult task, as these structures each have unique features and characteristics posing a variety of challenges to the robot design. This paper outlines the design and implementation of a novel robotic platform for deployment on ferromagnetic structures as an enabling structural health monitoring technology. The key feature of this design is the utilization of an attachment device which is an advancement of the common magnetic base found in the machine tool industry. By mechanizing this switchable magnetic circuit and redesigning it for light weight and compactness, it becomes an extremely efficient and robust means of attachment for use in various robotic and structural health monitoring applications. The ability to engage and disengage the magnet as needed, the very low power required to do so, the variety of applicable geometric configurations, and the ability to hold indefinitely once engaged make this device ideally suited for numerous robotic and distributed sensor network applications. Presented here are examples of the mechanized variable force magnets, as well as a prototype robot which has been successfully deployed on a large construction site. Also presented are other applications and future directions of this technology.

• Journal of the Korea Society of Computer and Information
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• v.11 no.1 s.39
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• pp.1-10
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• 2006

Load redistribution algorithm is a critical factor in computer system. In a receiver-initiated load redistribution algorithm, receiver(underloaded processor) continues to send unnecessary request messages for load transfer until a sender(overloaded processor) is found while the system load is light. Therefore, it yields many problems such as low CPU utilization and system throughput because of inefficient inter-processor communications until the receiver receives an accept message from the sender in this environment. This paper presents an approach based on genetic. algorithm(GA) for dynamic load redistribution in heterogeneous distributed systems. In this scheme the processors to which the requests are sent off are determined by the proposed GA to decrease unnecessary request messages.

• The Journal of Korean Medicine
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• v.28 no.1 s.69
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• pp.94-104
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• 2007

Objectives : This study investigated the effects of teaching English medical journals to traditional Korean medical students as a way of integrated curriculum, focusing on evidence-based traditional Korean medicine (EBKM) in the light of globalization of traditional Korean Medicine. Methods : 232 students (l16 1st year and t 16 2nd year) were asked to complete a questionnaire at the end of the course in order to validate the course's efficacy on acquisition and utilization of the latest medical knowledge as well as change of attitude toward English itself. Results : The courses were very useful in reducing discomfort toward English journals and to applying the latest medical knowledge to academic reports, clinical practices, and finally to establish abilities for EBKM. The 1st year students who took the courses for two semesters consecutively showed more significant satisfaction than the 2nd year students with only one semester. Conclusion : The findings suggest that English medical journals are an essential curriculum f3r the advance of EBKM and globalization of traditional Korean Medicine and therefore developing adequate textbooks, teaching methods, and quality of instructors should be considered for successful achievements.