• Composites Research
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• v.16 no.3
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• pp.58-67
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• 2003

To perform the realtime strain and fracture monitoring of the smart composite structures, two optical fiber sensor systems are proposed. The two types of the coherent sources were used for fracture signal detection - EDFA with FBG and EDFA with Fabry-Perot filter. These sources were coupled to EFPI sensors imbedded in composite specimens. To understand the characteristics of matrix crack signals, at first, we performed tensile tests using surface attached PZT sensors by changing the thickness and width of the specimens. This paper describes the implementation of time-frequency analysis such as short time Fourier transform (STFT) and wavelet transform (WT) for the quantitative evaluation of fracture signals. The experimental result shows the distinctive signal features in frequency domain due to the different specimen shapes. And, from the test of tensile load monitoring using optical fiber sensor systems, measured strain agreed with the value of electric strain gage and the fracture detection system could detect the moment of damage with high sensitivity to recognize the onset of micro-crack fracture signal.

• The Research Journal of the Costume Culture
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• v.19 no.1
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• pp.83-95
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• 2011

Today, a variety performance premiered in Korea, works of art as an advanced production planning and production system is becoming. Accordingly, the field of stage costume also increased collaboration with foreign producers and production systems and the advancement of the stage costume are required are becoming. The opening performance of the 30th anniversary of the Seoul Theater Festival was selected as Towol Theater Theater in 2009, April 16 to 26 of Picasso's women's costume is the study of production systems. This work directing and stage design by inviting domestic producers from foreign fields, and co-authored the work in the field of stage costumes in collaboration with foreign producers that are worth study and research work. In this study, this work has a practical study of costumes throughout the production system, an advanced stage costumes to contribute to the development of the field. The research methodology book data, collected papers, Internet resources through research and theoretical studies play 'Picasso's women's stage production of the award total to an empirical study was undertaken. The results of this study are as follows. First, the costume director for making a scholarly grasp of the direction of the investigation is ongoing throughout the process of creating the costumes. Second, foreign producers and co-author of the stage when the award, if other than purely domestic producers and create costumes to build production systems. Third, foreign producers and co-costume design and costume making coherent explanation for the processing of the list(Costume Breakdown List) are developed. Fourth, the actual performance over the director's intention to visualize the presentation was good enough, and the idea of the costume crew was taken to the director's idea of directing a play that reflected the will has a big meaning.

• Korean Journal of Optics and Photonics
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• v.31 no.6
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• pp.259-267
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• 2020

We evaluate the degradation of receiver sensitivity induced by direct and indirect exposure to solar irradiance in free-space optical communication systems. For this purpose, we calculate the variances of numerous noise components arising from solar irradiance, and then estimate the receiver sensitivity penalties for intensity-modulation/direct-detection and coherent systems. The results show that the penalties are less than 1.3 dB when indirect sunlight impinges on the detector, regardless of the system. However, the sensitivity penalties are estimated to be larger than 30 dB when the sunlight is directly incident upon the receiver. These penalties are barely reduced if we insert an optical polarizer, or if we adjust the bandwidth of an optical filter at the receiver to be as narrow as the signal's bandwidth.

• The Korean Society of Law and Medicine
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• v.11 no.2
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• pp.75-112
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• 2010

This article analyses the concept of medicine in the legal context. It is not easy to define the concept of medicine because medical practice has various dimensions and the situation in which the practice is performed has a broad variety. The duty of medical law is to build the boundary of protection in that the nature of medicine would not be distorted by the factors of social systems like industry or governmental authorities. Without understanding the various dimensions - especially the dimension of Humanities and Sociology - of the medicine it is not possible to draw the limit on the performance of medicine appropriately. Concerning the medical practice (especially in the context of the regulation of medical licence), the enacted law (Medical Act) defines the concept just for form's sake and it finally depends on the interpretation of the legal enforcement authorities. Moreover, between the judgments of the courts there exists no coherent principles for the regulation and the interpretation of the Medical Act depends often on the riskiness, the abstract concept, which finally leads the interpretation to depend on the subject of the practice. On the contrary, the development and scientific movement of the technology tends to tighten the range of the medical professionals of medical practice and the perspectives of the medicine. Medical act is actually oriented at the patient's understanding of him- or herself. The above-mentioned tendency of the interpretation and the legal policy could lead the medicine away from its nature.

• Journal of the Korean Society for information Management
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• v.22 no.2 s.56
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• pp.57-85
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• 2005

Bliss stated that one of the purposes of the classification was to demonstrate that a coherent and comprehensive system, based on the logical principles of classification and consistent with the systems of science and education, may be available to services in libraries, to aid revision of long established classifications and to provide an adaptable, efficient and economical classification, notation and index. A fundamental principle is the idea of subordination each specific subject is subordinated to the appropriate general one. The full scheme followed the publication of two massive theoretical works on the organization of knowledge. Its main feature was the carefully designed maul class order. reflecting Comte principle of gradation in speciality.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.6
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• pp.671-676
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• 2015

Cooperative networks eliminate shadow area using relay and enhance communication performance by creating virtual multi input multi output (MIMO) system. In this paper, we analyze the performance of cooperative networks which use coherent modulation scheme in source-relay nodes and differential modulation scheme in relay-destination nodes depending on the relay location. We consider the performance analysis of systems with and without the direct transmission between source and destination node where the direct transmission adopts differential modulation scheme. In addition, the performance of the system with fully differential modulation scheme is compared with the system using partially differential modulation scheme. The performance of system is based on the symbol error rate between source and destination node.

• Journal of Korean Elementary Science Education
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• v.33 no.2
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• pp.242-257
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• 2014

Researchers have employed a diversity of definitions and measurement methods for creativity. As a result, creativity research is underrepresented in the literature and the findings of different studies often prove difficult to draw into a coherent body of understanding. With regard to assessment, there are some important problems both in creativity research and practice, such as originality bias and Big-C creativity bias in teachers' perceptions about creativity and creative thinking, and additive rather than multiplicative scoring systems of creativity assessment. Drawing upon most widely accepted conceptions of the creativity construct, I defined 'student's scientific creativity' as the ability to make a product both original and useful to the student in terms of little-c creativity, and 'scientist's scientific creativity' as the ability to come up with a product both original and useful to the science community in terms of Big-C creativity. In this study, an 'Assessment Formula for Scientific Creativity' was developed, which is consisted of the multiplication of originality and usefulness scores rather than the sum of the two scores, and then, with scores calculated from the assessment formula, the scientific explanations generated by children were categorized into four types: routine, useful, original, and creative types. The assessment formula was revealed to be both valid and reliable. The implications of the assessment formula for scientific creativity are examined. The new assessment formula may contribute to the comprehensive understanding of scientific creativity to guide future research and the appropriate interpretation of previous studies.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.7
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• pp.3239-3267
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• 2018

Image and video dehazing is a popular topic in the field of computer vision and digital image processing. A fast, optimized dehazing algorithm was recently proposed that enhances contrast and reduces flickering artifacts in a dehazed video sequence by minimizing a cost function that makes transmission values spatially and temporally coherent. However, its fixed-size block partitioning leads to block effects. The temporal cost function also suffers from the temporal non-coherence of newly appearing objects in a scene. Further, the weak edges in a hazy image are not addressed. Hence, a video dehazing algorithm based on well designed spectral clustering is proposed. To avoid block artifacts, the spectral clustering is customized to segment static scenes to ensure the same target has the same transmission value. Assuming that edge images dehazed with optimized transmission values have richer detail than before restoration, an edge intensity function is added to the spatial consistency cost model. Atmospheric light is estimated using a modified quadtree search. Different temporal transmission models are established for newly appearing objects, static backgrounds, and moving objects. The experimental results demonstrate that the new method provides higher dehazing quality and lower time complexity than the previous technique.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.2
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• pp.670-683
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• 2016

Network coding, as a new technique to improve the throughput, is studied combined with multi-relay model in this paper to address the challenges of long distance and power limit in deep space communication. First, an amplify-and-forward relaying approach based on analog network coding (AFNC) is proposed in multi-relay network to improve the capacity for deep space communication system, where multiple relays are introduced to overcome the long distance link loss. The design of amplification coefficients is mathematically formulated as the optimization problem of maximizing SNR under sum-power constraint over relays. Then for a dual-hop relay network with a single source, the optimal amplification coefficients are derived when the multiple relays introduce non-coherent noise. Through theoretic analysis and simulation, it is shown that our approach can achieve the maximum transmission rate and perform better over single link transmission for deep space communication.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.7
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• pp.1718-1731
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• 1998

Digital quadrature demodulator is needed for the coherent demodulation in the digital communication systems such as Binary Phase-Shift-Keying, Quadrature Phase-Shift-Keying, and Quadrature Anmplitude Modulation. Conventaionally, the DDFS (Direct Digital Frequency Synthsizer) is used for generating the carrier signal and seperate multi-pliers are used for mixing. And the DDFS is implemented using the ROM (Read Only Memory), which can be a bottle-neck neck when the fast-speed and small-area implementation is required. A new architecture is developed, which employs the circular rotation mode of the CORDIC algorithm for signal mixing as well as carrier generation. To optimize the hardware design parameters, the finiteword-length effects of the proposed implementation arachitecture are analyzed in comparison with a conventional ROM-based architecture. The hardware costs are also estimated, which showed that the proposed architecture occupies only a third of the area of the conventional ROM-based architecture for the same performance. A full-custom VLSI is developed using the proposed architecture.