• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4475-4481
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• 2014

A histogram equalization method have been used traditionally for the image enhancement of low quality images. This uses the transformation function, which is a cumulative density function of an input image, and it has mathematically maximum entropy. This method, however, may yield whitening artifacts. This paper proposes the weighted histogram equalization method based on histogram equalization. It has Weber-Fechner's law for a human's vision characteristics, and a dynamic range modification to solve the problem of some methods, which yield a transformation function, regardless of the input image. Finally, the proposed transformation function was calculated using the weighted average of Weber-Fechner and the histogram equalization transformation functions in a modified dynamic range. The simulation results showed that the proposed algorithm effectively enhances the contrast in terms of the subjective quality. In addition, the proposed method has similar or higher entropy than the other conventional approaches.

• Archives of design research
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• v.13 no.3
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• pp.181-190
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• 2000

As human-centered design has become new paradigm in the whole field of design, they make an effort to understand users in the field of graphic interface design. However, there are not much of study to systematic process for human-centered approach in graphic interface design. Therefore, in this paper, the study was conducted to develop application methodology of prototype in the graphic user interface design process. The study consists of three sections. first, definition, types and application methods are introduced by secondary research. Second, all the knowledge gathered above by secondary research are integrated in the newly proposed Prototype-based interface design process. There are many types of prototype from idea sketches on the paper to final working prototype realized by computer. It is needed to develop and test appropriate prototype with appropriate techniques by objectives of the stages. Finally, the proposed prototype-base design process is verified and exemplified through the process of using prototype in the development of multi-user educational multimedia product.

• Journal of the Korean Society for information Management
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• v.41 no.3
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• pp.109-144
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• 2024

International research has actively explored and analyzed the implementation of e-learning platforms by libraries in response to the advancement of online learning models. In contrast, within Korea, while the significance and necessity of online library services and education are acknowledged, there remains a paucity of studies providing detailed methodologies for their implementation. This study aims to propose a practical e-learning platform for public libraries, detailing design guidelines and developing a prototype. Utilizing the Rapid Prototyping methodology, this study reviewed theoretical backgrounds and prior research, selecting Moodle LMS for initial design guidelines. The validity and reliability of the evaluation were assessed by experts and users. Based on the evaluation results, the final design guidelines and prototype of the e-learning platform for libraries were established. The final guidelines consist of four main functions, nine detailed functions, and forty specific instructions.

• The Journal of the Korea Contents Association
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• v.18 no.12
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• pp.372-382
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• 2018

Understanding is the foundation of music appreciation, the ultimate goal of music learning. The purpose of this research was to create a model for the integration and implementation of Gordon's music learning theory principles into Suzuki violin instruction. This research shows how audiation can be taught within the framework of the Suzuki philosophy and curriculum. It is expected that Gordon's music learning theory can provide Suzuki teachers with unique capabilities for teaching musical understanding, specifically through the development of audiation. Through an audiation-based approach to Suzuki instruction, thus, young violinists will be able to learn to comprehend the tonal and rhythmic aspects of the music they perform. Future researchers may wish to assemble a more complete guide to the tonal and rhythm patterns used in the Suzuki repertoire. Furthermore, additional lesson plans and activities can and should be developed that represent the application of music learning theory to Suzuki violin instruction.

• Journal of The Korean Association For Science Education
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• v.42 no.3
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• pp.341-356
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• 2022

This study aims to derive the implications of actor-network theory in science education research. To this end, previous studies applying the actor-network theory were analyzed. The study results show that educational research using actor-network theory can be divided into three main approaches. First, ANT was used as an epistemological perspective to construct an educational method or perspective, Second, ANT was used as an ontological perspective to recognize non-human agency, Third, ANT was used as a methodology for educational research. Based on the results, the possibility of contributing to science education research is discussed. As a new theoretical point of view, we hope that actor-network theory will be meaningful in science education practice and empirical research.

• 한국정책학회보
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• v.23 no.4
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• pp.179-209
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• 2014

Transition studies have been gaining attention among innovation researchers from the early 1990's mainly influenced by emerging global agendas on sustainability. In this paper, we review research issues and trends focusing on four prominent transition theories - Technological innovation systems, Multi-level perspective, Transition management and Strategic niche management. After reviewing main characteristics, research trends and debates of each theory from established literatures, we conduct comparative analysis of these theories and suggest integrated framework that can be considered when modeling transition policy. This integrated framework is applied to the case study on smart-grid policy of Korea.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2000.04a
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• pp.5-5
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• 2000

액체 추진 로켓 엔진의 고주파 연소 불안정 관련 이론은 대체로 연소기 내부의 음향 공명 모드와 분무 연소 과정의 상호 작용을 구동 메커니즘으로 전제하며 Rayleigh Criterion의 재해석에 기초하여 불안정성 평가를 위한 매개변수를 도입하고 연소 불안정성을 예측한다. 여기에는 음향장 분석 이론, 음향 불안정 이론, 연소응답 및 기화반응 이론 등이 포함된다. 본 연구에서는 LOX/RPl 추진제 조합의 액체 추진 로켓 엔진 연소기를 대상으로 다차원 순수 음향장 해석과 연소-음향장 분석을 통해 대상 엔진의 고주파 연소 불안정 특성을 예측하였다. 수동 제어 기기인 음향공 설치에 따른 연소기의 음향장 및 연소-음향장의 특성 변화를 고찰하고 위 결과를 종합하여 음향공의 연소 불안정 억제 성능 및 대상 엔진의 연소 불안정성을 평가하였다. 연소기 형상 및 음향공 설치에 따른 다차원 순수 음향장 해석은 상용코드인 ANSYS를 사용하여 수행하였다. 내부 유체는 압축성, 비점성 유체로 유체의 평균 유동은 무시하며 위치에 관계없이 균일한 물성치를 부여하였다. 정상상태 연소과정을 가정하고 평형 화학을 이용한 분석 결과로부터 연소 기체의 관련 물성치를 결정하였다. 연소기 길이 방향, 반경 방향, 원주 방향 격자점들의 음향 특성을 주파수 영역에 대해 해석하고 3차원 음향 모드 형상을 토대로 음향장을 분석하였다. 연소-음향장 해석은 음향 불안정 이론 중 n- $\tau$ 2 매개변수 기법을 사용하였다. 연료 액적의 분무 연소 과정을 1차원적으로 가정하고 정상상태의 평형 화학 계산 결과를 이용하여 엔진의 연소면을 1차원적으로 설정하였다. 상류 연소응답과 중립 안정 곡선을 토대로 대상 엔진의 연소 불안정 특성을 분석하였다.구 분석 결과 기술적 문제점으로는 배기 가스온도가 낮은데 따른 출구 부분의 Bearing, Sealing이 문제가 될 수 있다고 판단되며 배기 가스 자체에 대기 공기중에 함유되어 있던 습기가 얼어붙는(Icing화) 문제가 발생하기 때문에 배기가스의 Icing을 방지하기 위하여 압축기 끝단에서 공기를 추출하여 배기부분에 송출할 필요성이 있는 것으로 판단되었다. 출구가스의 기체 유동속도가 매우 빠르므로 (100-l10m.sec) 이를 완화하기 위한 디퓨저의 설계가 요구된다고 판단된다. 또 연소기 후방에 물을 주입하는 경우 열교환기 및 기타 부분품에 발생할 수 있는 부식 및 열교환 효율 저하도 간과할 수 없는 문제로 파악되었다. 이러한 기술적 문제가 적절히 해결되는 경우 비활성 가스 제너레이터는 민수용으로는 대형 빌딩, 산림, 유조선 등의 화재에 매우 적절히 사용되어 질 수 있을 뿐 아니라 군사적으로도 군사작전 중 및 공군 기지의 화재 그리고 지하벙커에 설치되어 있는 고급 첨단 군사 장비 등의 화재 뿐 아니라 대간첩작전 등에 효과적으로 활용될 수 있을 것으로 판단된다.가 작으며, 본 연소관에 충전된 RDX/AP계 추진제의 경우 추진제의 습기투과에 의한 추진제 물성 변화는 미미한 것으로 나타났다.의 향상으로, 음성개선에 효과적이라고 사료되었으며, 이 방법이 편측 성대마비 환자의 효과적인 음성개선의 치료방법의 하나로 응용될 수 있으리라 생각된다..7%), 혈액투석, 식도부분절제술 및 위루술·위회장문합술을 시행한 경우가 각 1례(2.9%)씩이었다. 13) 심각한 합병증은 9례(26.5%)에서 보였는데 그중 식도협착증이 6례(17.6%), 급성신부전증 1례(2.9%), 종격동기흉과 폐염이 병발한 경우와 폐염이 각 1례(2.9%)였다. 14)

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4D
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• pp.395-402
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• 2010

The seriousness of a traffic accident appears relatively higher on the curve sections compared with the straight sections due to a change in speed caused by a change in the driver's sight. In particular, the visual distortion phenomenon, one of the dangerous factors taking place on the curve sections, appears different according to the road's geometric design. Although it is a genuinely principal design factor which should be necessarily considered in designing a road, the previous researches on establishing the design standards for it have been insufficiently conducted. As a result, the establishment of the road design standards for the curve sections considering the sight distortion phenomenon is desperately required. This research examined the previous researches on the driver's behaviors, the driver's sight characteristics and the perceived curve radius on the curve sections, and developed the theoretical model of perceived curve radius to which a mathematical technique is applied in consideration of the visual distortion phenomenon on the two-lane curve sections in a local area. In addition, after the theoretical visual distortion was calculated on the basis of the theoretical model of perceived curve radius, the range of error on the theoretical recognition radius model formula was verified through comparing it with the previous researches' experiential visual distortion level and analyzing both of them. As a result, it was observed that as the curve radius practically increases in the theoretical recognition curve radius, the range of error tends to go down, which reflects well the characteristics of the curve sections on the road. Based on this research, it is expected that this research will be helpful to eliminate the safety defects when designing the curve sections and contribute to develop the road design standards considering human factors in the future.

• The Korean Journal of Food And Nutrition
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• v.13 no.4
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• pp.353-359
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• 2000

This study was carried out to introduce the fuzzy theory to standardize recipe of Korean foods, such as Pibimbab, Deonjang chigae (soybean stew), and Kimchi chigae (Kimchi stew). That is recipe of Pibimbab using fuzzy theory. Before this recipe was introduced, it thoroughly analyzed a number of data on Korean food such as materials used by cook book, commercial food, restaurants, food service operation recipes, and home recipes. And then the recipe of Korean food, Pibimbab will be possible to be standardized by fuzzy theory. The theory of fuzzy set is a theory of graded concept. The theory has matured into a wide ranging collection of concepts and techniques for dealing with complex phenomena. It defined a Membership function of fuzzy set by analyzed four sorts of data on Korean food, Pibimbab, and it established the fuzzy model using the quantity of materials as input and sensory test scores as output. This study will contribute to develop standard recipe for Korean foods and expert system of recipes using computer system.

• Journal of the Korean School Mathematics Society
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• v.13 no.4
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• pp.619-633
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• 2010

To offer insights in organizing professional development programs to promote teachers' substantial ongoing learning, this paper provides an overview of situative perspectives in terms of cognition as situated, cognition as social, and cognition as distributed. Then, it describes research findings on how mathematics teachers can enhance their knowledge and thus improve their instructional practices through participation in a professional development program that mainly provides opportunities to learn and analyze students' mathematical thinking and to perform mathematical tasks through which they interpret the understanding of students' mathematical thinking. Further, it shows that a knowledge of students' mathematical thinking is a powerful tool for teacher learning. In addition, it suggests that teacher-researcher and teacher-teacher collaborative activities influence considerably teachers' understanding and practice as such collaborations help teachers understand new ideas of teaching and develop innovative instructional practices.