• Title/Summary/Keyword: 시각왜곡도

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A Study on Distance Estimation in Virtual Space According to Change of Resolution of Static and Dynamic Image (가상현실공간에서 정적 및 동적 이미지의 해상도 변화에 따른 거리추정에 관한 연구)

  • Ryu, Jae-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.3
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    • pp.109-119
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    • 2011
  • The virtual reality (VR) technology has been used as the application of architectural presentation or simulation tool in the field of industry. The high immersion and intuitive visual information are the great merits of design evaluation or environmental simulation when we are using the virtual environments. But the distortion of distance perception in VR is still a big problem when the accuracy of distance presentation is strictly required. For example, distance estimation is especially important when the virtual environments are applied to the presentational tool for evaluation the space design or planning in the field of architecture. If there are some perception error between the built space in real and represented space in virtual, the accurate design evaluation or modification of design is hard to be carried out during the design development stage. In this paper, we have carried out some experiments about distance estimation in the immersive virtual environments to verify the factors and their influence. We made a hypothesis that the lack of the information for the user in VR causes the different distance estimation from the real world because users are usually comfortable with moving fast and long distance in VR environments compared with moving slow and short distance in real space. So, we carried out basic experiment to prove our hypothesis that the lack of information makes subjects estimate the distance of walking in VR shorter compared with the same distance in real. Also, among the factors that probably affect the distance estimation in VR, we have verified the influence of the image resolution. The influence of resolution degradation of image on the distance estimation was verified with the condition of static and dynamic images. The results showed that the resolution has deep relation with the distance estimation. For example, the subject underestimated the distance at the lower resolution condition. We also found the methods of the making the lower resolution image could affect on the visual perception of subjects.

Super Resolution Algorithm Based on Edge Map Interpolation and Improved Fast Back Projection Method in Mobile Devices (모바일 환경을 위해 에지맵 보간과 개선된 고속 Back Projection 기법을 이용한 Super Resolution 알고리즘)

  • Lee, Doo-Hee;Park, Dae-Hyun;Kim, Yoon
    • KIPS Transactions on Software and Data Engineering
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    • v.1 no.2
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    • pp.103-108
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    • 2012
  • Recently, as the prevalence of high-performance mobile devices and the application of the multimedia content are expanded, Super Resolution (SR) technique which reconstructs low resolution images to high resolution images is becoming important. And in the mobile devices, the development of the SR algorithm considering the operation quantity or memory is required because of using the restricted resources. In this paper, we propose a new single frame fast SR technique suitable for mobile devices. In order to prevent color distortion, we change RGB color domain to HSV color domain and process the brightness information V (Value) considering the characteristics of human visual perception. First, the low resolution image is enlarged by the improved fast back projection considering the noise elimination. And at the same time, the reliable edge map is extracted by using the LoG (Laplacian of Gaussian) filtering. Finally, the high definition picture is reconstructed by using the edge information and the improved back projection result. The proposed technique removes effectually the unnatural artefact which is generated during the super resolution restoration, and the edge information which can be lost is amended and emphasized. The experimental results indicate that the proposed algorithm provides better performance than conventional back projection and interpolation methods.

A Semi-fragile Watermarking Algorithm of 3D Mesh Model for Rapid Prototyping System Application (쾌속조형 시스템의 무결성 인증을 위한 3차원 메쉬 모델의 Semi-fragile 워터마킹)

  • Chi, Ji-Zhe;Kim, Jong-Weon;Choi, Jong-Uk
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.17 no.6
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    • pp.131-142
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    • 2007
  • In this paper, semi-fragile watermarking algorithm was proposed for the application to RP(Rapid Prototyping) system. In the case of the perceptual change or distortion of the original one, the prototype product will be affected from the process because the RP system requires the high precision measure. Therefore, the geometrical transformations like translation, rotation and scaling, the mesh order change and the file format change are used in the RP system because they do not change the basic shapes of the 3D models, but, the decimation and the smoothing are not used because they change the models. The proposed algorithm which is called semi-fragile watermarking is robust against to these kinds of manipulations which preserve the original shapes because it considers the limitations of the RP system, but fragile against to the other manipulations which change the original shapes. This algorithm does not change the model shapes after embedding the watermark information, that is, there is no shape difference between the original model and the watermarked model. so, it will be useful to authenticate the data integrity and hide the information in the field of mechanical engineering which requires the high precision measure.

Analysis of High School Students' Polar Literacy and Its Implications for Polar Education (고등학생들의 극지 소양 평가 결과 분석 및 극지 교육에의 시사점)

  • Chung, Sueim;Choi, Haneul;Kim, Minjee;Shin, Donghee
    • Journal of the Korean earth science society
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    • v.43 no.3
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    • pp.446-463
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    • 2022
  • This study suggests the need for polar literacy education as an effective conceptual system to explain climate change in terms of science education in line with the common effort of humankind to respond to global environmental changes. To this end, we investigated the status of polar literacy in high school students through quantitative tests and qualitative interviews and discussed the resulting implications. A total of 329 high school sophomore students from two high schools participated in a test consisting of 25 true and false questions developed by referring to the Polar Literacy Principles, while 13 students agreed to be interviewed. The results showed that a somewhat insufficient understanding and conceptual gaps appeared regarding several areas of the Polar Literacy Principles. Knowledge of the geographic features of the polar regions was weak, and little was known about the components and key characteristics of the cryosphere. The lack of understanding of these concepts results in the inability of students to link the operational mechanisms of polar and global climate change sufficiently. While accepting unsatisfactory concepts in the school curriculum without criticism from outside media, students perceived the mechanism of climate change as somewhat monotonous or distorted. Moreover, linguistic information, analogies, and visual observation were used as cognitive strategies to compensate for the ambiguous understanding of polar and climate change. Based on the abovementioned results, we argue that polar literacy education should be introduced as a new knowledge system that can be used to aid a systematic and comprehensive understanding of climate change within the school science curriculum. Additionally, we suggest the following implications: review the consistency of knowledge related to polar literacy in other subjects, provide critical standards for out-of-school media information related to climate change, examine students' misconceptions, and identify improved thinking strategies.

Artifact Reduction in Sparse-view Computed Tomography Image using Residual Learning Combined with Wavelet Transformation (Wavelet 변환과 결합한 잔차 학습을 이용한 희박뷰 전산화단층영상의 인공물 감소)

  • Lee, Seungwan
    • Journal of the Korean Society of Radiology
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    • v.16 no.3
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    • pp.295-302
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    • 2022
  • Sparse-view computed tomography (CT) imaging technique is able to reduce radiation dose, ensure the uniformity of image characteristics among projections and suppress noise. However, the reconstructed images obtained by the sparse-view CT imaging technique suffer from severe artifacts, resulting in the distortion of image quality and internal structures. In this study, we proposed a convolutional neural network (CNN) with wavelet transformation and residual learning for reducing artifacts in sparse-view CT image, and the performance of the trained model was quantitatively analyzed. The CNN consisted of wavelet transformation, convolutional and inverse wavelet transformation layers, and input and output images were configured as sparse-view CT images and residual images, respectively. For training the CNN, the loss function was calculated by using mean squared error (MSE), and the Adam function was used as an optimizer. Result images were obtained by subtracting the residual images, which were predicted by the trained model, from sparse-view CT images. The quantitative accuracy of the result images were measured in terms of peak signal-to-noise ratio (PSNR) and structural similarity (SSIM). The results showed that the trained model is able to improve the spatial resolution of the result images as well as reduce artifacts in sparse-view CT images effectively. Also, the trained model increased the PSNR and SSIM by 8.18% and 19.71% in comparison to the imaging model trained without wavelet transformation and residual learning, respectively. Therefore, the imaging model proposed in this study can restore the image quality of sparse-view CT image by reducing artifacts, improving spatial resolution and quantitative accuracy.

Analysis of data on prevention of school violence based on AI unsupervised learning (AI 비지도 학습 기반의 학교폭력 예방 데이터 분석)

  • Jung, Soyeong;Ma, Youngji;Koo, Dukhoi
    • 한국정보교육학회:학술대회논문집
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    • 2021.08a
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    • pp.85-91
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    • 2021
  • School violence has long been recognized as a social problem, and various efforts have been made to prevent it. In this study, we propose a system that can prevent school violence by analyzing data on the frequency of conversations between students, and identify peer relationships. The frequency of conversations between students in the class was quantified using a rating scale questionnaire, and this data was grouped into the appropriate number of clusters using the K-means algorithm. Additionally, the homeroom teacher observed the frequency and nature of conversations between students, and targeted specific individuals or groups for counseling and intervention, with the aim of reducing school violence. Data analysis revealed that the teachers' qualitative observations were consistent with the quantified data based on student questionnaires, and therefore applicable as quantitative data towards the identification and understanding of student relationships within the classroom. The study has potential limitations. The data used is subjective and based on peer evaluations which can be inconsistent as the students may use different criteria to evaluate one another. It is expected that this study will help homeroom teachers in their efforts to prevent school violence by understanding the relationships between students within the classroom.

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Traditional Music Reflected in the Shaman Documentary Films - Focusing of and - (무당 다큐멘터리 영화에 투사된 전통음악 - <사이에서>와 <땡큐 마스터 킴>을 중심으로 -)

  • Lee, Yong-Shik
    • (The) Research of the performance art and culture
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    • no.34
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    • pp.111-131
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    • 2017
  • Korean Shamanism has long been regarded as the peripheral cult or supersition by the majoriy of the society. This fact is a result by the influence of the mass media, especially the motion pictures, which intentionally reflected the negative images of the Shamanism. The documentary films, which stress the objectivity and the reality, rather disclose the neutral position toward the Shamanism. In fact, the directors of the documentary films who have more or less close relationship with the Shamanism have tried to exhibit the mental world and the traditionality of the Shamanism. In this paper, I will explore the value of Shamanism reflected in the documentary films. I focus of two films; directed by the Korean and directed by a foreigner. In this way, I can compare the attitudes of the two directors toward the Korean Shamanism. The director of confessed that he was attracted by the aspect of a musical underlied in the shaman ritual. However, the film does not show the artistic beauty of the shaman music because the director failed to understand the essential aspect of the shaman ritual, that is, the music. In this way, the director failed to show the distinct characteristics of the shamanism to the audience. The director of , a music herself, was focused on the music of the shamanism. The story flows to the adventure to seek a "master" with a long journey to enjoy diverse genres of Korean performing arts. This story resembles the epic shaman song, the Princess Bari. In this way, the audience can easily grasp the beauty of Korean culture. Music is said to be a universal language and, at the same time, a non-universal language which reflects a special trait of a cultural community. The Korean shaman ritual music is a non-universal language that is an accumulation of the Korean culture for a long time. The Korean director fails to exhibit the essential characteristics of the Shamanism since he does not have enough knowledge toward the shaman ritual music in . However, the foreign director, who is a music herself, successively disclose the underlying beauty of Korean shaman ritual music and Korean traditional culture in .

The Production Structure of Genetic Information in South Korea (한국의 유전적 정보 생산 구조)

  • Yi Cheong-Ho
    • Journal of Science and Technology Studies
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    • v.5 no.1 s.9
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    • pp.55-92
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    • 2005
  • The factors contributing to the formation of an important scientific concept in South Korea and its circulation in the society are the scientific knowledge that had been already formed, matured, and established in the U.S.A, Europe and Japan and has been introduced into Korea, and the institutions that have been formed during the recent modernization in South Korea. The concept of 'genetic information' cannot be an exception in this context. The concept of genetic information is the one that has been extended and intensified by the genomics and bioinformatics formed and matured through the Human Genome Projects from the former concept of inheritance or heredity within the framework of classical and molecular genetics. The purpose of this study was to find out 'how the production structure of genetic information in South Korea has been formed', under the perspective of the conceptual, epistemic, and institutional holisticity or integratedness in the concept and knowledge production structure idealized in Western advanced nations. The discourse of genetic engineering popular in the mid 1980's in South Korea has catalyzed the development of molecular biology. However, the institutional balance that had been established for the biochemistry departments in Natural Science College and Medical College was not formed between the genetic engineering and genetics departments in South Korea. Therefore, they were unable to achieve the more integrative and macro-level disciplinary impact on life sciences, largely due to institutional lack of the capable (human) genetics departments in some leading Korean colleges of Medicine. In genomics, the cutting-edge reprogramming and restructuring of the traditional genetics in the West, South Korea has not invested, even meagerly, in the infrastructure, fund, and research and development (R & D) for the Basic or First Phase of the research trajectory in the Human Genome Project. Without a minimal Basic Phase, the genomics research and development in Korea has been running more or less for the Advanced or Second Phase. Bioinformatics has started developing in Korea under a narrow perspective which regards it as a mere sub-discipline of information technology (IT). Having developed itself in parallel with genomics, bioinformatics contains its own unique logics and contents that can be both directly and indirectly connected to the information science and technology. As a result, bioinformatics reveals a defect in respect of being synergistically integrated into genetics and life sciences in Korea. Owing to the structural problem in the production, genetic information appears to be produced in a fragmented pattern in the Korean society since its fundamental base is weak and thin. A good example of the conceptual and institutional fragmentedness is that 'the genetics of individual identification' is not a normal integrated part of the Korean genetics, but a scientific practice exercised in the departments of legal medicine in a few Medical Colleges. And the environment contributing to the production structure of genetic information in South Korea today comprises 'sangmyung gonghak'(or life engineering) discourse and non-governmental organization movement.

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A Study on the Abstract Types of the Contemporary Landscape Design (현대조경디자인의 추상유형에 관한 연구)

  • Kim, Jun-Yon;Lee, Haeung-Yul;Bang, Kwang-Ja
    • Journal of the Korean Institute of Landscape Architecture
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    • v.36 no.6
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    • pp.1-11
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    • 2009
  • This study focuses on Abstract Types in Contemporary Landscape Design. The formation and artistry of contemporary landscape design reveals many areas which Previously have not been able to be expressed in scenic landscape thanks to the deviation of the genre in contemporary landscape and the hybridization that has occurred among architecture, landscape and art genres. The focus of this study is basic research concerning "the abstract", which is used as a creative artistic theory in a variety of art fields such as landscape, architecture and painting. Through a theoretical establishment of "the abstract", its process of change, and the discovery of its contemporary principles, the relationship between each art field in landscapes and the formation of the abstract, abstract language, and abstract properties have been studied. The use of the abstract in contemporary landscape design can be classified in three ways: Inductive abstract representing conceptual transcendental symbols not logically but rather through intuition and transcendental cognition to display the inner expressions, ideas and minds of the artists. Second, a deductive abstract represents an expansive, logical model for the simplification of objects, distortion, exaggeration based on knowledge and logical reasoning about objective fact based on traditional realism. The complexity of the abstract is a concept that is bound to both the deductive & inductive abstract. As a major trend, the concept of "The abstract" in contemporary landscape has been putting forth ever-deeper roots. New trends like abstract works and landscape architecture reflecting the artist's inner expression, in particular, will provide fertile soil for landscape in the future. Further research about the concept of "the abstract" will also be necessary in the time to come.

Dual Codec Based Joint Bit Rate Control Scheme for Terrestrial Stereoscopic 3DTV Broadcast (지상파 스테레오스코픽 3DTV 방송을 위한 이종 부호화기 기반 합동 비트율 제어 연구)

  • Chang, Yong-Jun;Kim, Mun-Churl
    • Journal of Broadcast Engineering
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    • v.16 no.2
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    • pp.216-225
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    • 2011
  • Following the proliferation of three-dimensional video contents and displays, many terrestrial broadcasting companies have been preparing for stereoscopic 3DTV service. In terrestrial stereoscopic broadcast, it is a difficult task to code and transmit two video sequences while sustaining as high quality as 2DTV broadcast due to the limited bandwidth defined by the existing digital TV standards such as ATSC. Thus, a terrestrial 3DTV broadcasting with a heterogeneous video codec system, where the left image and right images are based on MPEG-2 and H.264/AVC, respectively, is considered in order to achieve both high quality broadcasting service and compatibility for the existing 2DTV viewers. Without significant change in the current terrestrial broadcasting systems, we propose a joint rate control scheme for stereoscopic 3DTV service based on the heterogeneous dual codec systems. The proposed joint rate control scheme applies to the MPEG-2 encoder a quadratic rate-quantization model which is adopted in the H.264/AVC. Then the controller is designed for the sum of the left and right bitstreams to meet the bandwidth requirement of broadcasting standards while the sum of image distortions is minimized by adjusting quantization parameter obtained from the proposed optimization scheme. Besides, we consider a condition on maintaining quality difference between the left and right images around a desired level in the optimization in order to mitigate negative effects on human visual system. Experimental results demonstrate that the proposed bit rate control scheme outperforms the rate control method where each video coding standard uses its own bit rate control algorithm independently in terms of the increase in PSNR by 2.02%, the decrease in the average absolute quality difference by 77.6% and the reduction in the variance of the quality difference by 74.38%.