• 융합신호처리학회논문지
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• 제12권3호
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• pp.176-180
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• 2011

Even though algorithms for watermark embedding and extraction step are important issue for digital watermarking, watermark selection and post-processing can give us an opportunity to improve our algorithms and achieve higher performance. For this reason, we summarized the possibilities of improvements for digital watermarking by referring to the watermark merging techniques rather than embedding and extraction algorithms in this paper. We chose Cox's function as main embedding and extraction algorithm, and multiple barcode watermarks as a watermark. Each bit of the multiple copies of barcode watermark was embedded into a gray-scale image with Cox's embedding function. After extracting the numbers of watermark, we applied the watermark merging techniques; including the simple merging, N-step iterated merging, recover merging and combination of iterated-recover merging. Main consequence of our paper was the fact of finding out how multiple barcode watermarks and merging techniques can give us opportunities to improve the performance of algorithm.

• 한국가시화정보학회지
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• 제1권2호
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• pp.3-12
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• 2003

This paper describes the general aspects of various visualization techniques employed for marine engineering research including classical naval architecture, ocean engineering and other related topics. Visualization techniques performed mostly by authors' were introduced here, which range from old fashioned methods such as paint and tuft tests to the newly emerging PIV technique and Sonar in broad sense. Brief explanation of each technique was made for the instruction purposes. It is strongly recommended that the interdisciplinary project with experts in other research areas is necessary in order to develop more advanced and profitable techniques.

• 전력전자학회논문지
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• 제7권3호
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• pp.289-296
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• 2002

PWM 컨버터와 보상회로의 특이한 특성를 이용하는 새로운 이산시간 모델링 및 시뮬레이션 기법이 제안된다. 이러한 기법은 시스템 차수의 감소를 제공하고 수치적인 수렴 문제가 없는 보다 빠른 시뮬레이션을 가능하게 한다. 2단 출력 필터를 갖는 벅 컨버터가 제안된 기법의 유용성을 확인하기 위해 사용된다. 시뮬레이션 결과로부터, 이 방법은 높은 주파수가지 PWM 컨버터 시스템의 응답을 시뮬레이션 할 수 있음을 보여준다.

• 한국주거학회논문집
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• 제13권6호
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• pp.121-131
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• 2002

The rebuilding method for old apartment housing blocks has merits of providing new buildings and larger private living spaces. However, it causes many serious urban problems, such as shortage of infrastructure capacity, traffic congestion, reduction of building life, and deterioration of open space quality. Nowadays, remodeling is accepted as a way of overcoming such negative effects of the rebuilding method. This study focuses on the various techniques of remodeling. The results of this research are as follows; First, old apartment blocks provide poor level of service in general, so they have problems of bad accessibility, deterioration of facilities, and degraded landscape. In many cases, there is a hindrance from walking freely and security problem due to illegal privatization of public spaces. Second, various remodeling techniques are required to meet residents' different needs. The residents of apartment housing value private space above public space, and show low level of willingness to pay cost for remodeling. Third, based on these findings, some remodeling techniques are suggested - integration of a space to another, expansion of spaces, connection of spaces, reuses of roofs and walls, relocation and renovation of paths between buildings, and so on.

• The Journal of Korean Physical Therapy
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• 제6권1호
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• pp.155-161
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• 1994

Joint mobilization refers to techniques that are used to treat joint dysfunction such as when there is stiffness reversible joint hypomobility, or pain. Currently there are several schools of thought and treatment techniques that are popular in the United States. and leading practitioners and educators are attempting to blend common points to yield more uniform treatment from the various approaches. In order to effectively use joint mobilization for treatment, the practitioner must know and be able to evaluate the anatomy, arthrokinematics, and pathology of the neuromusculoskeletal system and to recognize when the techniques are indicated or when other stretching techniques would be more effective for regaining lost motion. Indiscriminate use of joint mobilization techniques when tot indicted could lead to potential harm to the patient's joints.

• 한국실내디자인학회논문집
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• 제38호
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• pp.83-90
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• 2003

Contemporary culture of consumption has been transferred from physical satisfaction in the past to the "pleasure" culture of consumption that satisfies emotional needs, generating a new design category - emotional design. The current study analyzes various environmental design techniques of the theme parks, which recognized early the importance of the "pleasure" culture of consumption and used the techniques for sales and as profit-making tools. This study also examines a trend of emotional design in environmental design techniques of the theme park and proves that the design techniques can be applied to a variety of interior design areas, as well as commercial facilities.mmercial facilities.

• 한국대기환경학회지
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• 제12권5호
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• pp.587-591
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• 1996

An intercomparison experiment was implemented to assess the uncertainties and precisions om atmospheric SO$_{2}$ measurement techiques including a pulsed fluorescence (P-F), a diffusion-scrubber /ion chromatography (D-I), and a mist-chamber/ion chromatography (M-I). Each of those three techniques was investigated by researchers at Seoul National University, Yonsei University, and Hankuk University of Foreign Studies, respectively. The concentrations of atmospheric SO$_{2}$ were determined concurrently using three independent measurement techniques at the Seoul National University campus, Korea during Nov.22 to Dec.2, 1995. While the results from the P-F and D-I techinques showed the very close agreements (within +-5%) throughout the experiment period, M-I technique showed systematically smaller values (up to 30%) than the other two techniques. Although sources of larger discrepancy between different techniques were mot identified, the lower SO$_{2}$ values of the M-I method may be related to the errors associated with sample collection effciency, mass flow rate measurements, and standardization of ion chromatography.

• International Journal of Aeronautical and Space Sciences
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• 제18권2호
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• pp.300-314
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• 2017

This paper examines finite rotation angle (FRA) applications for spacecraft attitude control. The coordinate transformation matrix and the attitude kinematics represented by FRAs are introduced. The interpolation techniques for the angular orientations are thoroughly investigated using the FRAs and the results are compared to those using traditional methods. The paper proposes trajectory description techniques by using extremely smooth polynomial functions of time, which can describe point-to-point attitude maneuvers in a realizable and accurate manner with the help of unique FRA features. In addition, new controller design techniques using the FRAs are developed by combining the proposed interpolation techniques with a model predictive control framework. The proposed techniques are validated through their attitude control applications for an aggressive point-to-point maneuver. Conclusively, the FRAs provide much more flexibility than quaternions and Euler angles when describing kinematics, generating trajectories, and designing attitude controllers for spacecraft.

• Smart Structures and Systems
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• 제7권2호
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• pp.153-167
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• 2011

The Subspace based System Identification Techniques (SSIT) have been very popular within the research circles in the last decade due to their proven superiority over the other existing system identification techniques. For operational (output only) modal analysis, the stochastic SSIT and for operational modal analysis in the presence of exogenous inputs, the combined deterministic stochastic SSIT have been used in the literature. This study compares the application of the two alternative techniques on a typical school building in Istanbul using 100 Monte Carlo simulations. The study clearly shows that the combined deterministic stochastic SSIT performs superior to the stochastic SSIT when the techniques are applied on noisy data from low to mid rise stiff structures.

• 한국IT서비스학회지
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• 제8권4호
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• pp.103-113
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• 2009

The industry of cultural digital contents has been regarded as the main next generation industry. Recently techniques for restoring cultural assets and the multiple usage of those have been developed in our country. Using computer graphics and image processing techniques, many cultural assets have been restored. If the focus for researches and supports to cultural assets restoration grows rapidly, we will create cultural and economical added-values and get the benefit of that technology. In this paper, we introduce the techniques for restoring cultural assets focused on computer graphics and image processing techniques.