• Wind and Structures
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• v.22 no.1
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• pp.1-16
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• 2016

The paper presents the state-of-the-art in aerodynamic performance of the modern horizontal axis wind turbine. The study examines the different complexities involved with wind turbine blade aerodynamic performance in open atmosphere and turbine wakes, and highlights the issues which require further investigations. Additionally, the latest concept of smart blades and frequently used wind turbine design analysis tools have also been discussed. The investigation made through this literature survey shows significant progress towards wind turbine aerodynamic performance improvements in general. However, still there are several parameters whose behavior and specific role in regulating the performance of the blades is yet to be elucidated clearly; in particular, the wind turbulence, rotational effects, coupled effect of turbulence and rotation, extreme wind events, formation and life time of the wakes.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.11a
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• pp.217-221
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• 2008

The goal of this research is to analyze interrelationship for layout of dwelling house and variation of its side plane by introducing concept of space in order to address as to how Korean traditional houses had been formed and varied in the middle of advancing modern city. In addition, this paper also has its meaning in a way that it identified how Korean traditional houses have been changed, and thus make residents more comfortable to live there by reviving their past characteristics, and make users have traditional food culture. Targeted area for this paper is limited to south-eastern area of Daegu such as Namsanjung, Myeongchijung, Sijangjung, Shinjung and Dalsungjng which was group dwelling houses of people of Chosun Dynasty during Japanese colonial rule' era ($1910{\sim}1945$). Among those places, the paper has chosen a place where Korea traditional houses were well preserved, variation of road and fields was less 1930s, and residential type is easy to effectively compared. As the result of this research, time when traditional cities were changed into new type of city residential area is believed to be around 1930s, and traditional residential area, through its transitional process, is believed to be changed to modern residential area. It also indicates that change of organizational road and fields directly had influence on change of houses.

• Research in Mathematical Education
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• v.5 no.2
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• pp.107-118
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• 2001

Mathematics subject of the seventh national curriculum in Korea, which has been effective since 2000, strongly encourages the use of calculators and computers to help children gain a better understanding of basic mathematical concepts and develop creative thinking and problem-solving skills without spending too much time and effort on making mechanical computations. Despite the recommendation by the national curriculum, however, only a small segment of elementary school teachers have been using calculators because of the fear that children\\`s dependence on calculators might bring about negative consequences. As a result, little research has been conducted in this area as well. This study has been conducted on the assumption that calculators have the potential for being a useful instructional tool in certain areas of elementary school mathematics education. To investigate the usefulness of calculators, a review was made of the scanty literature in the area. The literature review indicated that calculators are effective when they are used for the following purposes: understanding concepts and properties in numbers and operations, deducing mathematical rules, and solving problems. In view of the available research finding, we will give some concrete learning and teaching models of such uses of calculators. The teaching-learning models are organized around three categories: concept formation, discovery of principles and rules, and problem solving. Such organization is intended to help teachers use the models with ease.

• Journal of architectural history
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• v.22 no.5
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• pp.7-22
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• 2013

Gimlyong-sa temple has played an important role of Buddhist culture in Gyeongsangdo Provinces(嶺南地域) in the late Joseon Dynasty as the 31st head temple(本山) in the Japanese occupation. There are lots of architectural documentary records remained nevertheless, most of cultural heritages are destroyed by fire in 1997. There were 85 articles in five kinds of books which contained historical achievements of Gimlyong-sa temple and hermitages(Daeseongam(大成庵), Hwajangam(華藏庵), Yangjinam(養眞庵), Geum seondae(金仙臺), Dosoram(兜率庵), Myeongjeogam(明寂庵)). It is possible to understand the five situational peculiarities in the 17~19th century. At the first, they were compiled in 1914 to around 1930 by Kwon Sangro(權相老) to clarify the historical facts. Second, confirmed the formation process of the foundation narrative. Third, the meaning of Seolseondang(設禪堂), Manseru(萬歲樓) and Hyangnojeon(香爐殿) were recorded, it is possible to look at the concept of people at that time. Fourth, the great masters portraits were enshrined in hermitages, not in Gimlyong-sa temple. It means that a hermitage is not for only self-discipline or living but assembly of religious orders(門派). Fifth, Chimgye(枕溪), the great Buddhist clergy and carpenter of Gimlyong-sa, was nationwide active worker in 19th century because he was also in a charge of investment manager for construction.

• The Korean Fashion and Textile Research Journal
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• v.10 no.3
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• pp.364-370
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• 2008

This research aims to recognize necessity of modern expression of traditional pattern, understand the matter which is expressed when developing design using traditional pattern, and find the solutions. As the solutions, this research presents design of traditional pattern using symmetry concept and works on the possibility of symmetry as the pattern design. So this research carried out in-depth interview to textile designer working at Gyeongsangnam-do, analyzed the substances. The main results are as follows. First, the presented problems of developing common pattern design and designing using traditional pattern show the necessities for adequate harmony among conception of creative idea, traditional pattern and present pattern. As the solution, the efficient design principles are required. Second, the seven traditional figures can present design applying symmetry, also draw the 8 mapping models for the visuality and utilization. Third, the symmetry-applied traditional pattern design makes it possible for the traditional figure to be represented with the creative and modern sense and provides easier way to the design development by complementing the pattern design formation. As the result, symmetry-utilized traditional pattern design improvement shows the expectation that it will increase the design development ability and ease the figure drawing. In addition, the pattern development which can be applied to any figure presents the time efficiency as well as possibility of the high added value textile industry.

• Korean Institute of Interior Design Journal
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• v.19 no.1
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• pp.137-147
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• 2010

The purpose of this study is to research a method of creating a new type of boundary by repeated disposition of single unit of modularized membrane successively. In the contemporary architectural indoor space, more highly dimensional analysis of boundary is required and the necessity of establishing boundary of a new concept that may satisfy cultural value, social value and artistic value as a whole as well as aesthetic and functional merit has been increased. In order to create a membrane that may fulfil the requirements of the diversified programs of space like this, an approach of complicated mechanism and high-dimensional calculation are required. At this time, digital GA modelling, parametric modelling technique may expand its range of possibility. One thing to be noted at this juncture is that indefinite expandability involved in digital modelling technique, modelling by grid of absolute and relative coordinates and convenience of systematization may surpass limitation of analogue or simple numerical calculation being progressed in the past. And in order to create solid process including unit modelling or pattern formation, Precise calculation process of computer is necessitated inevitably.

• Journal of The Korean Association For Science Education
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• v.39 no.1
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• pp.89-99
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• 2019

The purpose of this study is to investigate the effect of students' formation of evolutionary concept and learning on the development of digital teaching materials. The explanation of biological evolution, which explains the changes that living organisms undergo over a long period of time, can provide various contents for use in a book. The production and editing of images in digital textbooks would provide explanation of difficult concepts in a fun way. For this study, we designed instructional materials consisting of four class hours using iBooks Author, an electronic book authoring tool based on the 5E learning cycle model. In order to verify the effectiveness of the developed digital textbooks, we compared instructions by the general textbooks to those using digital textbooks. Both teaching through general textbook form and teaching using digital textbook materials had a significant effect on the formation of the concept of evolution, but interest in biological science and evolution increased significantly only in the group taught using digital textbooks. As a result of testing the instruction effect by the digital textbooks by classifying the students by type, the group that is familiar with smart devices was more active and interesting in class depending on digital literacy. The satisfaction of the developed digital textbooks also showed a positive score in the group with high digital literacy. The results of this study suggest that the development of digital textbooks in the unit of evolution can be an instructional material for easy and interesting approach to difficult concepts in the teaching of evolution.

• Korean Journal of Radiology
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• v.24 no.7
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• pp.647-659
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• 2023

Objective: The study was conducted to investigate the effect of correct occlusion of the left atrial appendage (LAA) on intracardiac blood flow and thrombus formation in patients with atrial fibrillation (AF) using four-dimensional (4D) flow magnetic resonance imaging (MRI) and three-dimensional (3D)-printed phantoms. Materials and Methods: Three life-sized 3D-printed left atrium (LA) phantoms, including a pre-occlusion (i.e., before the occlusion procedure) model and correctly and incorrectly occluded post-procedural models, were constructed based on cardiac computed tomography images from an 86-year-old male with long-standing persistent AF. A custom-made closed-loop flow circuit was set up, and pulsatile simulated pulmonary venous flow was delivered by a pump. 4D flow MRI was performed using a 3T scanner, and the images were analyzed using MATLAB-based software (R2020b; Mathworks). Flow metrics associated with blood stasis and thrombogenicity, such as the volume of stasis defined by the velocity threshold ($\left|\vec{V}\right|$ < 3 cm/s), surface-and-time-averaged wall shear stress (WSS), and endothelial cell activation potential (ECAP), were analyzed and compared among the three LA phantom models. Results: Different spatial distributions, orientations, and magnitudes of LA flow were directly visualized within the three LA phantoms using 4D flow MRI. The time-averaged volume and its ratio to the corresponding entire volume of LA flow stasis were consistently reduced in the correctly occluded model (70.82 mL and 39.0%, respectively), followed by the incorrectly occluded (73.17 mL and 39.0%, respectively) and pre-occlusion (79.11 mL and 39.7%, respectively) models. The surfaceand-time-averaged WSS and ECAP were also lowest in the correctly occluded model (0.048 Pa and 4.004 Pa^-1, respectively), followed by the incorrectly occluded (0.059 Pa and 4.792 Pa^-1, respectively) and pre-occlusion (0.072 Pa and 5.861 Pa^-1, respectively) models. Conclusion: These findings suggest that a correctly occluded LAA leads to the greatest reduction in LA flow stasis and thrombogenicity, presenting a tentative procedural goal to maximize clinical benefits in patients with AF.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.2 s.161
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• pp.292-299
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• 2007

Development of portable device measuring the vital sign continuously with no limit of time and space is absolutely prerequisite for the U-health care that grafts the ubiquitous concept into medical system. Accordingly, it requires to develop a garment style apparatus for measuring vital-sign that is easy to wear on for a long time period. This study suggests a method to improve the insulation of electric cable and the skin adhesion of electrode by integrating the electric conductive material to garment, in order to develop a garment apparatus for measuring ECG for U-health care. Results of the research are as follows; In order to provide the adjacent conductive yarns with insulation, braid with narrow woven end was interlaced using polyester yarn. As a result, the direct contact between electric conductive yarns was restrained, which would be interposed into pin-tuck structured cable. Washable silicone gel applied around the electrode made of electric conductive fabric improved the adhesion, which prevents electrodes from dropping off from the skin surface during body movement. ECG signals on the human subject were tested using the garment apparatus developed by the above method. And the result was that the clear QRS wave formation in the typical form of ECG could be measured in both conditions of still and moving state as well. The result of this study is expected to contribute for the production of U-health care related medical apparatus by accelerating the practical uses of the garment measuring vital sign at a reasonable price.

• Proceedings of the KIEE Conference
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• 2006.07d
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• pp.2167-2168
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• 2006

Mobilecomputer of offers more fundamental role than role assistance enemy of modem technology equipment and new Information Technology can reconsider, and reconstruct creatively accuracy of physiological concept. That military register symptoms are developed of disease, before far before rehalibitation, of for possibility that can intervene in process that motive change of military register symptoms after rehalibitation. But, that many parameters become analysis target and mathematical settlement and equalization system of noted data of that is huge, same time collection of all datas can lift difficulty etc.. These main weakness puts in structural relation between elements that compose system. Therefore, dynamics research that time urea of systematic adjustment has selected method code Tuesday nerve dynamics enemy who groping of approach that become analysis point is proper and do with recycling bioelectricity signal. Nature model of do living body signal digital analysis chapter as research result could be developed and scientific foundation groping could apply HSS (Hardware-software system) by rehalibitation purpose. Special quality that isdone radish form Tuesday of bioelectricity signal formation furthermore studied, and by the result, fundamental process of bodysignal in do structure circuit form of analog - digital water supply height modelling do can.