• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.1
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• pp.82-93
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• 2002

The effects of the interaction between the flow and temperature field and a boundary layer due to a variety of the height of a vortex generator are experimentally investigated. The test facility consists of a boundary-layer wind tunnel with the vortex generator protruding from the bottom surface. In order to control the strength of the longitudinal vortices, the angle of attack and the spacing distance of the vortex generator are 20 degree and 40 mm, respectively. The height of the vortex generator (H) is 15 mm, 20 mm and 30 mm and the cord length of it is 50 mm. Three-component mean velocity measurements are made using a 5-hole probe system and the surface temperature distribution is measured by the hue capturing method using thermochromatic liquid crystals. By using the method mentioned above, the following conclusions are obtained from the present experiment. The boundary layer is thinned in the downwash region where the strong downflow and the lateral outflow of the boundary layer fluid occur and thickened in the upwash re,3ion where the longitudinal vortex sweeps low momentum fluid away from the bottom surface. In case that the height of the vortex generator increases, the averaged circulation and the maximum vorticity of the vortex pair decrease. The contours of the non-dimensional temperature show the similar trends fur all the cases (H=15 mm, 20 mm and 30 mm). The peak augmentation of the distribution of the local non-dimensional temperature occurs in the downwash region near the point of minimum boundary-layer thickness.

• KIEAE Journal
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• v.17 no.3
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• pp.51-58
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• 2017

Purpose: G-SEED's evaluation of existing buildings in Korea is an important point because the energy consumption and CO2 emissions of existing buildings are continuously increasing due to the aging of buildings over time. In 2016, the government has set up a 'Green Remodeling Certification Standard' in G-SEED in order to revitalize the green remodeling business of existing buildings. As a result, G-SEED is distinguished between buildings with green remodeling and buildings with general remodeling. Therefore, this study analyzed the system of the certification of the green remodeling building which is aimed at improving the performance of the building. Method: First, we analyze characteristics of the existing building certification standards of G-SEED(Korea), LEED(USA), and BREEAM(UK). Second, the evaluation criteria are based on the G-SEED Green Remodeling Certification, 2016, LEED for BD + C: New construction and major renovation v.4, BREEAM UK Non-Domestic Refurbishment and Fit-out 2014. Based on the analysis results, we propose the improvement direction of G-SEED Green Remodeling Certification Standard. Result: Existing buildings should be classified into 'existing building certification' for re-certification and 'green remodeling certification' accompanied by building performance improvement. In addition, building green buildings through performance improvement should include not only energy performance, but also creating a pleasant indoor environment and minimizing environmental impact. Finally, existing buildings have accumulated information on energy and resource use, and a performance improvement plan should be established based on this information.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.12B
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• pp.1474-1480
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• 2011

Recently the mobile IPTV service has been spread through the wireless LAN(WLAN). In order to provide the commercial mobile IPTV service through the WLAN, re-authentication for the mobile IPTV terminal is required whenever the mobile terminal roams between APs(Access Points). The most popular one of the authentication protocol standards for the wired and/or wireless LAN is IEEE 802.1X. However IEEE 802.1X takes much time to authenticate the terminal and is not adequate for the seamless mobile IPTV service. We introduce the session key and separate the user authentication and the hardware authentication. And we strengthen the device authentication by the initial registration. By these, the proposed authentication protocol reduces the authentication time and can protect the authentication key securely.

• Journal of the Korea Society of Computer and Information
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• v.17 no.12
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• pp.259-267
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• 2012

The objectives of this study are to study and propose the learning elements and it's teaching methods for Information Ethics by expert survey. In recent days, Internet is the new field of our living, but teaching the students in elementary and secondary schools the subject of Information Ethics which purpose is to have positive attitude of utilizing Internet is not properly executed. The first step to teach Information Ethics in schools is to choose the learning elements in Information Ethics. Therefore, this paper is to choose the learning elements and re-arrange them with point of view to elementary and secondary schools. And more, in order to teach the students the learning elements of Information Ethics effectively, we propose the proper teaching methods to the learning elements by teacher's survey. The learning elements and teaching methods in Information Ethics is not the perfect guide to teach students in school, but the output of this study will be the good guide to revise the Information Ethics-related curriculums and product the textbooks about Information Ethics.

• Journal of Gifted/Talented Education
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• v.19 no.1
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• pp.119-140
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• 2009

This paper examined its possibility and made its new definition by finding relevant bases in order to make a close inquiry into its Identity and direction at this point when cyber-based gifted education academy is established and operated again by its necessity And 4 models which can be used in special education for the gifted were developed making a link with special education for the gifted by collecting and re-classifying cyber educational methods developed by basic research as priority of the educational method which is considered to be the most urgent issue in practical cyber learning. It is a project-type cooperation education model, an information collection-type research education model, a community-type discussion education model, and a problem focus-type e-PBL education model. To apply developed leaching-learning models to reality, students at gifted education academy in Gyeonggi Cyber Gifted Province were imputed models in different ways respectively for 4 months. As a result of analysis and statistical data of activity level and satisfaction level of students who participated in learning activity, it appeared that high level of satisfaction and active activity level were induced compared to the previous method based on tasks. It is expected that this paper will provide the bases when each cyber-based gifted education academy plans operation plan later on, and it will provide proper methods when cyber guidance teachers plan class activities.

• Archives of design research
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• v.15 no.3
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• pp.259-270
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• 2002

In 1995, When people read a poem, the image that a poet intends to convey to readers shows in various colors according to the status of their emotion. Poetry is a bridge as well as a text, which connects this world and the poet's world. In such relationship, the communication through Types occurs. The realm of application of modern typography is widening due to the development of the Internet and mass media, and the ways of expression of which are changing with the help of lots of softwares. So, the modern typography is re-born as an organic language which is alive, breathing. Therefore, Types has the structural character similar to that of Typography, which is a language of image, creating today's movement, time, and space. The already existing poetry contains meanings but has a descriptive structures. On contrary, compared with the former, the type appeared in Hangul Concrete Poetry., itself is a poem in another realm due to the formality native to Hangul, and which appears in non-linear structure. So, in this thesis, I will analyze the formality and non-linear structure of Hangul Typography in order to widen the realm of research on typography, which is a very meaningful trial to visualize the literature.

• The Korean Journal of Air & Space Law and Policy
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• v.21 no.2
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• pp.123-155
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• 2006

2001. 9. 11 aviation terror showed us that there are lots of problems in aviation security and we need efficient counter-plans. According to this event, many countries are coming up with various countermeasures. After first hijacking in 1950, the aviation terror is occurring with more various methods until these days. And the scale is bigger than former so they're making much bigger damages. Especially, the case of 9.11 terror attracted people's eye of the world because of enormous casualties and damages. It aroused many people's self-awakening therefore as an important factor the security is given much weight in the aviation safety. In order to keep the step like this tendency and the development of aviation security, beginning with America lots of countries of the world are pursuing diverse aviation security's counter-plans of new side. At this point of time, for our development in aviation industry we should make efficient aviation security countermeasures. In this study, We compared our aviation security activities with major countries after 9.11 terror.

• Advances in aircraft and spacecraft science
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• v.3 no.3
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• pp.243-257
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• 2016

The increase of air traffic volume has brought an increasing amount of issues related to carbon and NOx emissions and noise pollution. Aircraft manufacturers are concentrating their efforts to develop technologies to increase aircraft efficiency and consequently to reduce pollutant discharge and noise emission. Ultra High By-Pass Ratio engine concepts provide reduction of fuel consumption and noise emission thanks to a decrease of the jet velocity exhausting from the engine nozzles. In order to keep same thrust, mass flow and therefore section of fan/nacelle diameter should be increased to compensate velocity reduction. Such feature will lead to close-coupled architectures for engine installation under the wing. A strong jet-wing interaction resulting in a change of turbulent mixing in the aeroacoustic field as well as noise enhancement due to reflection phenomena are therefore expected. On the other hand, pressure fluctuations on the wing as well as on the fuselage represent the forcing loads, which stress panels causing vibrations. Some of these vibrations are re-emitted in the aeroacoustic field as vibration noise, some of them are transmitted in the cockpit as interior noise. In the present work, the interaction between a jet and wing or fuselage is reproduced by a flat surface tangential to an incompressible jet at different radial distances from the nozzle axis. The change in the aerodynamic field due to the presence of the rigid plate was studied by hot wire anemometric measurements, which provided a characterization of mean and fluctuating velocity fields in the jet plume. Pressure fluctuations acting on the flat plate were studied by cavity-mounted microphones which provided point-wise measurements in stream-wise and spanwise directions. Statistical description of velocity and wall pressure fields are determined in terms of Fourier-domain quantities. Scaling laws for pressure auto-spectra and coherence functions are also presented.

• Educational Technology International
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• v.11 no.1
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• pp.27-46
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• 2010

The purpose of this paper is to apply the newly developed SICAT teaching and learning model to the actual scene of teaching and learning and draw a point of discussion for utilizing teaching and learning model, by uncovering the satisfaction of students and the inhibiting/facilitating elements when using the model. SICAT(Scientific Inquiry and Creative Activity with Technology; from here on SICAT), a teaching and learning model custom-built for engineering education, was developed, as more and more people paid attention to the demand for creative engineers. It was developed from the basis of PBL(Problem Based Learning), includes three sub-types which can be applied to the actual theory, design, and experimentation fields within engineering education. The three sub-types, which are ARDA(Analysis-Reasoning Activity & Discussion-Argumentation Activity), CoCD (Collaboration Activity & Capstone Design Activity), and ReSh(Reflection Activity & Sharing Activity), respectively support deductive and argumentation activities, creative design and collaboration activities, and retrospection and sharing activities. However, no research has been conducted to investigate whether or not there are inhibiting or facilitating elements in the application procedure, or what the rate of satisfaction for students is, when applying the SICAT model, which was newly developed to innovate existing engineering education, to the actual site of teaching and learning. Therefore, this research applied three types of SICAT teaching and learning models to the theory, design, and experimentation classes at the department of materials science and engineering at Hanyang University for eight weeks. After application, the students, teachers and tutors were surveyed and interviewed, and then the results analyzed in order to uncover inhibiting/facilitating elements and the rate of satisfaction. The satisfaction rate of students from the SICAT teaching and learning model was 3.78(in a perfect score of 5: The A type-3.65, The C type-3.80, The R type-3.90), and inhibiting/facilitating elements were drawn from the aspects of learning activities, support system. In conclusion, they can be contributed for implications of SICAT teaching and learning model universal use at engineering education in University.

• The Korean Journal of Archival Studies
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• no.23
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• pp.141-178
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• 2010

The Administration of Labor was responsible for the technical and practical functions like policy-making of labor matters and implementing the relevant laws. However, there has been a few record transferred to the National Archives to help find out the labor policy-making process. This is one of the typical examples that shows the discontinuity and unbalance, and disorderly filing of the administrative records in Korea. Naturally it is almost impossible to retrieve the appropriate content through the records file-name. Users should be at the trouble to compare the record items and their content one by one. For the re-organization of the Administration of Labor' records, this research suggests the four-level analysis of functions of the Administration. The Administration of Labor' survived records could be linked to each level function. And the publication of the 'Records Abstract Catalog' providing users with more information about the records would pave the way for easier access to the records. In addition, it also suggests the logical re-filing of the survived records of which we cannot find the order or sequence. This re-organization of the survived records would help to establish the acquisition and appraisal policy of the labor records as well as the new way of description and finding tool hereafter. Drawing up labor history map is a starting point for the acquisition strategy of the labor records, which could allow users to gain systematic access on the survived records. Of course, extensive investigation and research on the survived records is a prerequisite for the map. It would be required to research on the survived records of the other government agencies, including economic-social area ministries and investigation agencies and the National Assembly as well. It is also needed to arrange and typify the significant incidents and activities on thematic and periodic frames in the labor history. If possible to understand or connect the survived records and these accomplishments comprehensively, it would be of great help for the acquisition of the labor records and the related oral records projects.