• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.348-351
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• 2002

Recently, the medical imaging field has been digitalized by the development of computer science and digitization of the medical devices. There are needs of the medical imaging database service and long term storage today because of the installation of PACS system following DICOM standards, telemedicine and etc. and ,also, the illegal distortion of the medical information, data authentication and copyright are being happened. In this paper, we propose watermarking technique as a method which can protect private informations and medical imaging from geometric distortion. Because many watermarks for images are sensitive to geometric distortion, we present a algorithm that is insensitive to RST distortion in medical image. we observed the robustness against several of the signal processing and attacks in medical imaging field by embedding watermark after making a region which is insensitive to RST distortion by using FFT and LPM transformation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.5
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• pp.796-804
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• 1994

This paper presents Inverse SAR imaging algorithm for a unknown velocity target and a real ISAR data is processed and applied to the algorithm. The real ISAR data is obtained by transmitting a number of pulse modulated by a stepped-frequency method and the received data are undersampled. We present a method applicable for the case of a undersampled data base. In this method, the original echoed signal is mixed with a reference signal to make it unaliased, followed by being interpolated. Target`s velocity required for the algorithm is estimated via subaperture processing and after the coordinate transformation into squint-mode SAR with the estimated velocity, a recently proposed SAR/ISAR imaging algorithm derived without any approximation is utilized to produce the output image. We also propose an ISAR image scheme that is usable when a target changes its velocity during ISAR data acquisition time.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10b
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• pp.1345-1348
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• 2000

Computers and communication technologies have been brought tremendous change to various aspects of an ever-fast changing world at present. Particularly, the use of internet and cyberspace is widespread in every comer of our life. We developed a cyber shell museum using an animation technology. It was developed for educational purposes, and accessible through the world wide web of internet. Cyber shell museum is consisted of five compartment including rare shells, marvelous shells, shell of the world, the shell of Korea and its story of shells. The database contains the pictures and related information of the shell and it implies not only animation display but also text information. The files of database were classified depending on the species, genus, family, order, and class and division of the shell. Picture of shells is displayed and user may reach the image and virtual view information by clicking through the object displayed. This provides multiple techniques to user may manipulate, visualize and interact with image on the web. And every such transformation as translation, rotation, and scaling can be applied in the picture interactively for the convenient and effective viewing.

• Korean Journal of Optics and Photonics
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• v.27 no.3
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• pp.101-105
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• 2016

In this study we propose the novel optimization method of the phase-only computer-generated hologram (CGH), to improve calculation speed compared to the conventional method. While the conventional method is calculated using numerical analysis, the novel method is calculated using the phase-shift characteristic of Fourier transformation. In addition, the selectivity of noise filtering lets it decrease the calculation time. The validity of the reconstructed image using the novel method is verified by comparing simulation results to ideal and conventional data, and the improvement of texture and sharpness of the reconstructed image is confirmed by simulation.

• Journal of The Korean Digital Architecture Interior Association
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• v.8 no.1
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• pp.65-74
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• 2008

Light creates ambiance that affects our impression of space. Before the modern age, the role of light is a religious factor and a primitive state to see. In the modern space design, light is used to achieve the continuous transformation and translation of building's image. Ever-changing space is a flexible corresponding of space to its environment, caused by certain dynamic light. The space turn into some other thing from what it was before, or just changing its character. approaching men and society with different meanings. The purpose of this study is to explore the relation between light(natural and artificial) and ever-changing space through the case study. The impacts of light on ever-changing in today's space design can be summarized as follows. 1) Materialization of light in space design. Nowadays light becomes a form itself. The geometric properties of the space form playa secondary role as compared to the importance assigned to light. 2) Pixelization of space by a light effect. The impacts of digital technology on the space design have come through enhancing the 'pixelization' of the surface from which buildings are made their responsiveness and adaptability to changing needs. The surface with ever-changing lights that blur the boundary of space and expand the image of space.

• Journal of Electrical Engineering and Technology
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• v.9 no.4
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• pp.1418-1425
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• 2014

In ultrasonic medical imaging, spatial compounding of images is a technique where ultrasonic beam is steered to examine patient tissues in multiple angles. In the conventional ultrasonic diagnostic imaging, the steering of the ultrasonic beam is achieved electronically using the phased array transducer elements. In this paper, a spatial compounding approach is presented where the ultrasonic probe element is rotated mechanically and the beam steering is achieved mechanically. In the spatial compounding, target position is computed using the value of the rotation axis and the transducer array angular position. However, in the process of the rotation mechanism construction and the control system there arises the inevitable uncertainties in these values. These geometric parameter errors result in the target position error, and the consequence is a blurry compounded image. In order to reduce these target position errors, we present a spatial compounding scheme where error correcting transformation matrices are computed and applied to the raw images before spatial compounding to reduce the blurriness in the compounded image. The proposed scheme is illustrated using phantom and live scan images of human knee, and it is shown that the blurriness is effectively reduced.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.562-564
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• 2001

Transformation of molecular film occurs only usually in air-water interface, 2 dimensions domain's growth and crash are achieved. Organic matter thin film that accumulate molecular film in archaism board only that consist of growth of domain can understand correct special quality of accumulation film supplying information about fine structure and properties of matter of device observing information and so on that is surface forward player and optic enemy using AFM one of SPM application by nano electronics. The stable images are probably due to a strong interaction between the monolayer film and glass substrate. We are unable to obtain molecule resolution in images of the films but did see a marked contrast between images of the bare substrate and those with the network structure film deposited onto it. Formation that prevent when gas phase state and liquid phase state measure but Could know organic matter that molecules form equal and stable film when molecules were not distributed evenly, and accumulated in solid state only.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11a
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• pp.425-428
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• 2002

본 논문에서는 한 장의 정면 얼굴 영상만으로 회전 변형을 수행할 수 있는 새로운 영상기반렌더링(Image Based Rendering, IBR) 기법을 제안한다. 3차원 기하학적 모델을 대신하면서 수평 회전 변형을 연출하기 위해, 특정 인물의 정면, 좌우 반측면, 좌우 측면의 얼굴 영상에 대한 표준 메쉬 집합을 작성한다. 변형하고자 하는 임의의 인물에 대해서는 정면 영상에 대한 메쉬만을 작성하고, 나머지 측면 참조 메쉬들은 표준 메쉬 집합에 의해 자동으로 생성된다. 입체적인 회전 효과를 연출하기 위해, 회전 변형시 발생할 수 있는 제어점들간의 중첩 및 역전을 허용하도록 기존의 두 단계 메쉬워프 알고리즘을 개선한 역전가능 메쉬워프 알고리즘(invertible meshwarp algorithm)을 제안한다. 이 알고리즘을 이용하여 다양한 남녀노소의 정면 얼굴 영상에 대해 회전에 따른 포즈 변형을 수행하여 비교적 자연스러운 포즈 변형 결과를 얻었다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.167-170
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• 2006

This study proposes a new wavelet watermark technique based on the Linear Bit Expansion. To ensure the security of the watermark, it is Amold Transformed before embedding. Then the wavelet transformation of watermark and original images is processed. Since the size of the watermark image is a quarter of the original site, it uses linear bit-expansion to enlarge the watermark image. Lastly, watermark is inserted in a given intensity to the corresponding low frequency subbands of the wavelet-transformed images proposed in this paper. When detecting the presence of watermark, the similarity between extracted watermark and the original watermark is compared applying the F norm function.

• Journal of Power System Engineering
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• v.15 no.5
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• pp.91-96
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• 2011

The handling ability of containers at the terminal strongly depends on the performance of the cargo handling system such as RTGC(Rubber Tired Gantry Crane) and RMGC(Rail Mounted Gantry Crane). This paper introduces a guide line measurement system on the operating condition, in which two camera are installed to detect the guide line. Because the line tracking is the basic technique for control system design of RTGC, it is necessary to develop a useful and reliable measurement system. If the displacement and angle of the RTGC relative to a guide line as the trajectory to follow is obtained, the position of RTGC is automatically calculated. Therefore, in this paper, a camera-based measurement system is introduced. The proposed measurement system is robust against light fluctuation and cracks of the guide line. This system consists of two camera and a PC which are installed at the lower side of the RTGC. Two edges of the guide line are detected from an input image taken by the cameras in the moving state, and these positions are determined in a Hough parameter space by using the Hough transformation method. From the experimental results, the accuracy and usefulness of the proposed system is evaluated by comparing other instruments.