• Title/Summary/Keyword: Perspective-Transform

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A study on the torsional frequency measurement of wind turbine blades (대형 풍력 블레이드의 비틀림 주파수 측정에 관한 고찰)

  • Ji-Hoon Kim;Jin Bum Moon;Min-Gyu Kang;Woo-Kyoung Lee;Si-Hyun Kim;Jisang Park
    • Journal of Wind Energy
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    • v.13 no.3
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    • pp.13-21
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    • 2022
  • When a wind turbine is designed, the dynamic stability of the system as well as the dynamic characteristics of the main components such as blades, hub, main shaft and tower must be evaluated. In particular, the natural frequencies of a blade, as a main load-generating component, need to be measured and assessed by component level testing. In conventional practice, the natural frequencies of a blade are determined as the measured frequencies near the reference frequencies provided by FE analysis results. But the reference frequencies are also uncertain since designers have difficulty distinguishing the torsional mode shape among the analysis results due to the complexity of its mode shape. So, in conventional practice, the determination of a measured torsional frequency inevitably contains uncertainty. Therefore, a novel method to definitely determine the torsional frequencies from the experimental data itself is necessary. In this paper, a new methodology to measure the torsional frequency of a blade was studied from the perspective of a modal test procedure, data processing method and mode determination logic. Finally, the validity of the method that can measure torsional frequency without reference FE analysis results was verified by applying it to an actual large wind turbine blade

Enhancing Productivity through Innovation: Korea's Response to Competitiveness Challenges (경쟁력 도전에 대한 한국의 대응 - 혁신을 통한 생산성 향상 -)

  • Suh, Joonghae
    • KDI Journal of Economic Policy
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    • v.27 no.1
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    • pp.211-238
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    • 2005
  • Korea is far behind other OECD countries in economy-wise productivity: Korea's labor productivity in terms of GDP per hour worked is the lowest among OECD countries. Against the existing productivity gap, there is a worrying sign in Korea's investment trend - rapid fall in machinery and equipment investment with slow increase in R&D investment. The challenge facing Korea is how to transform her economy from catching-up model to a knowledge-based one. The paper shows that, in tandem with the structural changes that today's Korean industries are experiencing, industry's innovation system is also changing. Innovation networks are emerging as the result of economy-wise restructuring since the financial crisis of 1997 and, though still not a dominant force, the newly emerging innovation networks will be the main threads of industry's innovation activities in the future. The changes in industrial innovation system would positively contribute in raising the productivity of the Korean economy. The paper contains a case study on Korea's automobile industry in order to highlight some of main characteristics of the structural changes, in addition to a chapter that gives an overview of the evolutionary paths of the Korea's industrial innovation. The paper assesses that changes can be considered as a positive sign of future growth perspective; but there are further challenges to make the Korea's industrial innovation system effective. The list of such challenges includes strengthening upstream sectors of currently leading industries, expanding the innovation base to SME and promoting technological co-operation between domestic firms and foreign firms.

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Research on Landscape Plan Strategy of Urban Waterside Space Buffer Zone - Focused on the Case of the Resilient Perspective of Plan - (도시 수변 완충지역의 경관 계획에 관한 연구 - 탄성 (resilient) 관점의 계획 사례분석을 중심으로 -)

  • Yang, Meng;Hong, Kwan-Seon
    • The Journal of the Korea Contents Association
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    • v.20 no.7
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    • pp.404-416
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    • 2020
  • Flooding is an unavoidable natural disaster for the city. Flood disasters seriously undermine the city's economy, safety, and sustained development. In the course of development and construction of waterfront space in the same city, the construction of basic disaster prevention facilities cannot be avoided completely even if huge amounts of capital are invested to reduce the economic damage of flooding. The cost of rebuilding the city after the disaster is much higher than the cost of building disaster prevention facilities. In recent years, the theory of elasticity in urban reconstruction and so on has been a subject of city problem solving, creating widespread discussion and attention in academia. In other words, how to transform the concept of elasticity into practice based on theoretical and empirical factors is a real problem facing urban disaster. Through theoretical literature on the waterfront (space) buffer zone of a city (flood-weak area) and the case study of the city's practice, this paper tries to clarify the element of 5R, the theory of elastomeric fire prevention, and present detailed measures accordingly. In addition, the following two problems are addressed while emphasizing the feasibility of implementing the urban waterfront (space) plan of the elastomeric element around the urban water buffer zone. First, the means of disaster prevention planning are used to mitigate conflicts between individual utility of urban waterfront and disaster prevention functions in waterfront buffer zones, and second, the waterfront buffer zone can respond to flood-causing problems in terms of disaster prevention as much as possible through the elastic disaster prevention plan.

Analyzing Science-gifted Middle School Students' Understandings of Nature of Science (NOS) (중학교 과학영재들의 과학의 본성에 대한 인식 분석)

  • Park, Eun-I;Hong, Hun-Gi
    • Journal of Gifted/Talented Education
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    • v.21 no.2
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    • pp.391-405
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    • 2011
  • The nature of science has been recognized in a great deal in the field of science education. However, only few innovative programs are offered for science-gifted students to improve their recognition of the nature of science. The current study describes and analyzes science-gifted students' understandings of the nature of science (NOS). In addition, the study looks into contradictory views among the aspects of NOS, which are fundamental data in constructing target programs on NOS for science gifted students. Data used in this study were collected from 73 middle school science-gifted students using an open-ended questionnaire, VNOS. The results of this study showed that the participants' understanding of NOS was significantly distributed on naive or transition view except for 'tentative NOS', and the results revealed inconsistent view among the aspects of NOS. This study proposes two suggestions to enhance the recognition of science-gifted on NOS of science to informed state and to have consistent perspectives with other areas. First, the role of experiment has to be changed-it should be the process in constructing scientific knowledge rather than an instrument to check scientific knowledge to transform perspective on experimental data and scientific knowledge. Second, various opportunities must be provided to science-gifted students, so they can experience the culture and community of scientists and science to gain a wider insight of science.

Development of an Intelligent Trading System Using Support Vector Machines and Genetic Algorithms (Support Vector Machines와 유전자 알고리즘을 이용한 지능형 트레이딩 시스템 개발)

  • Kim, Sun-Woong;Ahn, Hyun-Chul
    • Journal of Intelligence and Information Systems
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    • v.16 no.1
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    • pp.71-92
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    • 2010
  • As the use of trading systems increases recently, many researchers are interested in developing intelligent trading systems using artificial intelligence techniques. However, most prior studies on trading systems have common limitations. First, they just adopted several technical indicators based on stock indices as independent variables although there are a variety of variables that can be used as independent variables for predicting the market. In addition, most of them focus on developing a model that predicts the direction of the stock market indices rather than one that can generate trading signals for maximizing returns. Thus, in this study, we propose a novel intelligent trading system that mitigates these limitations. It is designed to use both the technical indicators and the other non-price variables on the market. Also, it adopts 'two-threshold mechanism' so that it can transform the outcome of the stock market prediction model based on support vector machines to the trading decision signals like buy, sell or hold. To validate the usefulness of the proposed system, we applied it to the real world data-the KOSPI200 index from May 2004 to December 2009. As a result, we found that the proposed system outperformed other comparative models from the perspective of 'rate of return'.

Representation and Re-presentation in the Theatre of Tadeusz Kantor (환영과 현실의 경계에 서다 - <비엘로폴, 비엘로폴>을 중심으로 본 타데우즈 칸토르의 연극 미학)

  • Sohn, Wonjung
    • Journal of Korean Theatre Studies Association
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    • no.49
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    • pp.75-100
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    • 2013
  • An on-going creative process was the major principle of Kantor's artistic endeavors. Kantor's emphasis on process grew out of his frustration with the experience of creation being isolated from the audience in the present time, during the moments of encounter. At the same time, however, Kantor was always aware of the fact that the first night of each and every performance that he made was the last point of his creative intervention. Despite being performed live in the present time, Kantor saw theatre essentially as an end product. This does not mean that Kantor abandoned the concept of on-going process, for process was for the artist a means to reject the idea of a finished work of art and to denounce the feeling of satisfaction derived from the traditional denouement in representational theatre. For him, theatre that dominated his time isolated the audience from the art work and the artist, and from this perspective his continual emphasis on process should be understood as an aesthetic principle in order to open up and expand the dimension of art into the realm of the spectator so that the experiences of both the artist and spectator may coexist. The heaviest barrier that separated the artist and his work from its audience was the creative structure that governed Western art. In theatre it was the dramatic structure that was the main object of his series of severe challenges. Not only did it fail to represent reality but it distorted reality, creating nothing but artificial illusion. Under this condition, all that was permitted to the audience was mirages. However, Kantor never completely discarded illusion from his theatre. The point for him was always to created a circumstance where the illusory reality of drama comes to exist within the dimensions of our reality. It was Kantor's belief that instead of a total denial of illusion, his theatre should strategically accommodate illusion which comes from reality. And, the aim of Kantor's theatrical experiments was to invite the audience into this ambience and transform the experience of his audience into a much more participatory one. This paper traces the ways in which Kantor transgressed the dominating conventions of representational, literary theatre, and how such attempts induced an alternative mode of spectatorship. The study will begin from an investigation into Kantor's attitude towards illusion and reality, and then move onto a closer inspection of how he spatially and dramaturgically materialized his concepts on stage, giving special focus on Wielopole, Wielopole.

Between Regime Change and Political Development: Myanmar's Defective Democracy and the Task for the Political Development (체제 전환과 정치발전의 사이에서: 미얀마의 결손민주주의와 정치발전의 과제)

  • JANG, Junyoung
    • The Southeast Asian review
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    • v.28 no.4
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    • pp.161-196
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    • 2018
  • The major object of this study is to analyze the political development of Myanmar's civilian government on the concept of defective democracy, and to investigate the main actors who delayed or stymied political development and their interrelation. In doing so, this study suggests the tasks required for political development overcoming the current political structure and behavior. The civilian government, which was launched in 2016, failed to achieve positive political development by following the behavior of military authoritarianism in terms of exercise of power and decision making structure. On the perspective of the government, delegative democracy and domain democracy have been strengthening since one person has taken over all political power and hesitate to take horizontal accountability for each power organizations. The military, which is responsible for national defence and security seeks illiberal democracy and exclusive democracy, keeping on an undemocratic constitution by the military and Burman ethnocentrism. The reasons why defective democracy has been occurred are that the lack of a group to run a democratic institutions and the limitation of power structure that fails to adhere to the principle of civilian control to the military due to long-term military rule. Therefore, there is a need for military's come back to barracks and transform the power structure to democratic of the civilian government which is tamed an authoritarian order for the political development in Myanmar. In order to achieve this, this study concludes that setting up a empowered democratic government is required.

Korean Morphological Analysis Method Based on BERT-Fused Transformer Model (BERT-Fused Transformer 모델에 기반한 한국어 형태소 분석 기법)

  • Lee, Changjae;Ra, Dongyul
    • KIPS Transactions on Software and Data Engineering
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    • v.11 no.4
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    • pp.169-178
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    • 2022
  • Morphemes are most primitive units in a language that lose their original meaning when segmented into smaller parts. In Korean, a sentence is a sequence of eojeols (words) separated by spaces. Each eojeol comprises one or more morphemes. Korean morphological analysis (KMA) is to divide eojeols in a given Korean sentence into morpheme units. It also includes assigning appropriate part-of-speech(POS) tags to the resulting morphemes. KMA is one of the most important tasks in Korean natural language processing (NLP). Improving the performance of KMA is closely related to increasing performance of Korean NLP tasks. Recent research on KMA has begun to adopt the approach of machine translation (MT) models. MT is to convert a sequence (sentence) of units of one domain into a sequence (sentence) of units of another domain. Neural machine translation (NMT) stands for the approaches of MT that exploit neural network models. From a perspective of MT, KMA is to transform an input sequence of units belonging to the eojeol domain into a sequence of units in the morpheme domain. In this paper, we propose a deep learning model for KMA. The backbone of our model is based on the BERT-fused model which was shown to achieve high performance on NMT. The BERT-fused model utilizes Transformer, a representative model employed by NMT, and BERT which is a language representation model that has enabled a significant advance in NLP. The experimental results show that our model achieves 98.24 F1-Score.

A Study on the Improvement of Color Detection Performance of Unmanned Salt Collection Vehicles Using an Image Processing Algorithm (이미지 처리 알고리즘을 이용한 무인 천일염 포집장치의 색상 검출 성능 향상에 관한 연구)

  • Kim, Seon-Deok;Ahn, Byong-Won;Park, Kyung-Min
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.6
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    • pp.1054-1062
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    • 2022
  • The population of Korea's solar salt-producing regions is rapidly aging, resulting in a decrease in the number of productive workers. In solar salt production, salt collection is the most labor-intensive operation because existing salt collection vehicles require human operators. Therefore, we intend to develop an unmanned solar salt collection vehicle to reduce manpower requirements. The unmanned solar salt collection vehicle is designed to identify the salt collection status and location in the salt plate via color detection, the color detection performance is a crucial consideration. Therefore, an image processing algorithm was developed to improve color detection performance. The algorithm generates an around-view image by using resizing, rotation, and perspective transformation of the input image, set the RoI to transform only the corresponding area to the HSV color model, and detects the color area through an AND operation. The detected color area was expanded and noise removed using morphological operations, and the area of the detection region was calculated using contour and image moment. The calculated area is compared with the set area to determine the location case of the collection vehicle within the salt plate. The performance was evaluated by comparing the calculated area of the final detected color to which the algorithm was applied and the area of the detected color in each step of the algorithm. It was confirmed that the color detection performance is improved by at least 25-99% for salt detection, at least 44-68% for red color, and an average of 7% for blue and an average of 15% for green. The proposed approach is well-suited to the operation of unmanned solar salt collection vehicles.

Development of curriculum for humanity education in Christian university (기독교대학 인성교육을 위한 교과목 개발)

  • Hyang-Sook Park
    • Journal of Christian Education in Korea
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    • v.72
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    • pp.317-339
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    • 2022
  • The purpose of this study is to develop liberal arts subjects for humanity education in Christian universities. Christian universities need to attempt Christian humanity education through Christian educational interpretation of humanity. This study defines the humanity not character or personality but rather humanity. Humanity is starting from an understanding of human conditions. And it is a perspective toward oneself and others based on human ontological questions and life style. Human is a being with developmental crises and are marginal being with existential anxiety. Therefore, humanity education of Christian universities should be a place to face the void of finite humans in order to understand what kind of existence they are and to transform their epistemology to understand self and the world. Christian humanity education will be realized by two approaches. The first is a theoria approach that extends from a two-dimensional understanding of the self and experienced reality to the speculative and introspective pursuit of the ultimate truth, The second is a praxis approach that consist of the interaction of reflection to human's act and reflective behavior. Therefore, this study develops a subject focused on a speculative and reflective understanding of humanity as an case of a liberal arts subject for humanity education in a Christian university, and a subject focusing on the understanding of reflexively participating in the actual social situation, which is the context of humanity.