• Journal of Electrical Engineering and Technology
• /
• v.11 no.4
• /
• pp.1020-1026
• /
• 2016

Motion estimation (ME) algorithms supporting quarter-pixel accuracy have been recently introduced to retain detailed motion information for high quality of video in the state-of-the-art video compression standard of H.264/AVC. Conventional sub-pixel ME algorithms in the spatial domain are faced with a common problem of computational complexity because of embedded interpolation schemes. This paper proposes a low-complexity sub-pixel motion estimation algorithm in the transform domain utilizing shifting matrix. Simulations are performed to compare the performances of spatial-domain ME algorithms and transform-domain ME algorithms in terms of peak signal-to-noise ratio (PSNR) and the number of bits per frame. Simulation results confirm that the transform-domain approach not only improves the video quality and the compression efficiency, but also remarkably alleviates the computational complexity, compared to the spatial-domain approach.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 1997.10a
• /
• pp.20-25
• /
• 1997

Magnetic bearings have been widely used to support rotors without any physical contact. This however, requires the control of five degrees-of-freedom and needs a separate driving motor. This paper introduces selfbearing motors which use the combination of a rotary motor and a magnetic bearing. These motors are suitable for use in high speed rotor or in special circumstances because they are small in size and can replace the contact components. The radial type one has the merit of being small in size and capable of controlling two degrees-of-freedom in x and y directions. The axial type motor controls only one degree-of-freedom in z direction. Theoretical background of the functions, of the motor and magnetic bearing will also be introduced. New research works are reviewed and the application in rotary blood pump is discussed.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.5
• /
• pp.2142-2161
• /
• 2018

Distance dynamics model is an excellent model for uncovering the community structure of a complex network. However, the model has poor robustness. To improve the robustness, we design an enhanced distance dynamics model based on Ego-Leader and propose a corresponding community detection algorithm, called E-Attractor. The main contributions of E-Attractor are as follows. First, to get rid of sensitive parameter ${\lambda}$, Ego-Leader is introduced into the distance dynamics model to determine the influence of an exclusive neighbor on the distance. Second, based on top-k Ego-Leader, we design an enhanced distance dynamics model. In contrast to the traditional model, enhanced model has better robustness for all networks. Extensive experiments show that E-Attractor has good performance relative to several state-of-the-art algorithms.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 1999.10a
• /
• pp.297-304
• /
• 1999

the devastating earthquake which occurred in Turkey on August 187, 1999, reminds again us the necessity of the preparedness for the earthquake hazard. the level of earthquake engineering in Koran is still low due to the short period of the research and development in this field. Therefore the most efficient way of promoting our technology in this field is considered to collect the information on the state of the art and practice developed in the advanced countries in earthquake engineering and to analyze the advantages and disadvantages and then reflect these to the new seismic codes. for this purpose this study reviews the concept and main characteristics of Eurocode 8 and the findings of many researches that have been performed for the improvement of EC8. Finally the seismic performance evaluation of the building structures designed according to EC8. and the relevant recommendations are summarized.

• Current Optics and Photonics
• /
• v.3 no.5
• /
• pp.390-400
• /
• 2019

Encrypted images obtained through double random phase-encoding (DRPE) occupy considerable storage space. We propose efficient compression schemes to reduce the size of the encrypted data. In the proposed schemes, two state-of-art compression methods of JPEG and JP2K are applied to the quantized encrypted phase images obtained by combining the DRPE algorithm with the virtual photon counting imaging technique. We compute the nonlinear cross-correlation between the registered reference images and the compressed input images to verify the performance of the compression of double random phase-encoded images. We show quantitatively through experiments that considerable compression of the encrypted image data can be achieved while security and authentication factors are completely preserved.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.15 no.2
• /
• pp.786-799
• /
• 2021

Road damage detection is important for road maintenance. With the development of deep learning, more and more road damage detection methods have been proposed, such as Fast R-CNN, Faster R-CNN, Mask R-CNN and RetinaNet. However, because shallow and deep layers cannot be extracted at the same time, the existing methods do not perform well in detecting objects with fewer samples. In addition, these methods cannot obtain a highly accurate detecting bounding box. This paper presents a Multi-level Feature Pyramids method based on M2det. Because the feature layer has multi-scale and multi-level architecture, the feature layer containing more information and obvious features can be extracted. Moreover, an attention mechanism is used to improve the accuracy of local boundary boxes in the dataset. Experimental results show that the proposed method is better than the current state-of-the-art methods.

• Annual Conference of KIPS
• /
• 2004.05a
• /
• pp.781-784
• /
• 2004

본 시스템은 어항속에 있는 물고기 움직임을 추적하기 위해 두 대의 카메라로부터 동시에 독립된 영상을 획득하고 획득된 영상을 처리하여 좌표를 얻어내고 3차원 좌표로 생성해내는 시스템이다. 제안하는 방법은 크게 두 대의 카메라로부터 동시에 영상을 획득하는 방법과 획득된 영상에 대한 처리 및 물체 위치 검출, 그리고 3차원 좌표 생성으로 구성된다. Frame grabber를 사용하여 두 개의 카메라로부터 동시에 영상을 획득하며, 3개의 연속된 프레임에 대한 차영상과 ART2(Adaptive Resonance Theory)를 이용하여 각각의 영상에서의 물고기 위치를 검출한다. 검출된 각각의 좌표를 병합하여 3차원 좌표를 생성하며, 추적 결과는 OpenGL을 이용하여 3차원으로 재생한다.

• Journal of Engineering Education Research
• /
• v.22 no.4
• /
• pp.71-77
• /
• 2019

Capstone design is a very important college course that enhances students' creativity and skills. However, in most universities, the operation of capstone design is operated by the experience and intuition of the advisor, and it is somewhat lacking in the generation of useful results such as patent rights and technology start-up from the capstone design result. In this study, we proposed a performance - based capstone design operation model through patent linkage so that the capstone design class can create creative and useful results. The proposed operating model includes support for research on prior art of patent information utilization, patent right of idea, and technology commercialization. The proposed operating model was directly applied to the capstone design class in the university, and it was confirmed that useful results such as expansion of the scope of the research achievement and technology start - up were created compared to the existing operation model.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.25 no.1
• /
• pp.55-64
• /
• 2022

Identifying warships contacted at sea is important to prepare for threats. It is necessary to obtain a basis to identify warships. In this study, we propose a 2-step model that acquires the warship's type and hullnumber with identification information from the warship images. The model classifies the warship's type and detects its hullnumber area by applying object detection, then recognizes hullnumber through text recognition algorithms. Proposed model achieved high performance by using state-of-the-art deep learning algorithms.

• Journal of Sensor Science and Technology
• /
• v.31 no.6
• /
• pp.403-410
• /
• 2022

Flexible and wearable sensing technologies have emerged as a result of developments in interdisciplinary research across several fields, bringing together various subjects such as biology, physics, chemistry, and information technology. Moreover, various types of flexible wearable biocompatible devices, such customized medical equipment, soft robotics, bio-batteries, and electronic skin patches, have been developed over the last several years that are extensively employed to monitor biological signals. As a result, we present an updated overview of new bio-implantable sensor technologies for various applications and a brief review of the state-of-the-art technologies.