• Korean Architects
• /
• no.5 s.206
• /
• pp.8-28
• /
• 1986

• Journal of KIISE:Computer Systems and Theory
• /
• v.32 no.2
• /
• pp.95-105
• /
• 2005

This paper proposes a new dynamic video adaptation scheme that could generate an adapted video stream customized to the requesting mobile device and current network status without repeated decode-encode cycles. In the proposed adaptation scheme, the characteristics of the video codec such as MPEG-1/-2/-4 are analyzed in advance focused on the relationships between the size and Quality of the encoded video stream, and they are stored in the proxy as a codec-dependent characteristic table. When a mobile device requests a video stream, it is dynamically decoded-encoded in the proxy with the highest quality to extract the contents-dependent attributes of the requested video stream. By comparing these attributes with codec-dependent characteristic table, the size and Quality of the requested video stream when being adapted to the target mobile device could be predicted. With this prediction, a version of adapted video stream, that meets the size constraints of mobile device while keeping the quality of encoded video stream as high as possible, could be selected without repeated decode-encode cycles. Experimental results show that the errors in our proposed scheme are less than 5% and produce an appropriate adapted video stream very quickly. It could be used t(1 build a proxy server for mobile devices that could quickly transcode the video streams widely spread in Internet which are encoded with various video codecs.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.40 no.2
• /
• pp.138-143
• /
• 2004

This experimental paper deals with the performance of tanks that are turned the active A.R.T(Anti-Rolling Tank) when the fluid transfers from wing tank to the opposite tank by the power developed by the automatic control system (INTERING Stabilizer), which was installed in the fishery training ship T/S. A - RA (G/T:990 tons) of Cheju National University. In this paper, the author has tested the performance of INTERING Stabilizer for the signals obtained by the inclinometer in irregular waves and compared with the results obtained in passive mode operation at stop and at various ship speeds. The performances of the system were confirmed the results as follows through the tests: 1. The average amplitude and significant roll (${\pi}$1/3) of the passive and active mode operations in the condition of stoped engine and underway were obtained 8.30$^{\circ}$, 4.37$^{\circ}$, 8.30$^{\circ}$, 4.37$^{\circ}$, and 5.01$^{\circ}$, 4.36$^{\circ}$, 5.50$^{\circ}$, 5.10$^{\circ}$, respectively. 2. The rates of performance of active mode operations were carried out during a sea trial in the condition of stop engine and underway resulted in 47.5%, 12.7%, respectively, therefore the active mode operation estimated to be improved more than passive mode operation. 3. Active - A.R.T by INTERING Stabilizer didn't affect the amplitude of pitching.

• Journal of the Korea Concrete Institute
• /
• v.26 no.3
• /
• pp.385-392
• /
• 2014

Reshoring makes slab deflect and support its own weight. The construction loads on the slabs in lower levels decrease using the reshoring. Simplified analysis proposed by ACI 347.2R-05 showed that if the reshoring is applied, construction loads on slabs and shores, and quantities of forms and shores decreased by 40%, 23%, 40%, and 50%, respectively. Shores' loads were comparatively measured on site. The measured reshore load was half of the load before removing the shores and was also lower than the measured shore load by 35%. To verify the safety of the reshoring, deflections of beams and strains of beam longitudinal bars were also measured. The maximum deflection was only L/5000 and the maximum bar strain was only 3.6% of the yield strain. Consequently, reshoring neither cause problems on the safety nor serviceability. In addition, the beam load was expected from the measured shores' loads and it coincides well with the predicted value by the simplified analysis of ACI 347.2R-05.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.48 no.4
• /
• pp.107-115
• /
• 2011

In this paper, we proposed fast and efficient algorithm for detecting near-duplication based on content based retrieval in large scale video database. For handling large amounts of video easily, we split the video into small segment using scene change detection. In case of video services and copyright related business models, it is need to technology that detect near-duplicates, that longer matched video than to search video containing short part or a frame of original. To detect near-duplicate video, we proposed motion distribution and frame descriptor in a video segment. The motion distribution descriptor is constructed by obtaining motion vector from macro blocks during the video decoding process. When matching between descriptors, we use the motion distribution descriptor as filtering to improving matching speed. However, motion distribution has low discriminability. To improve discrimination, we decide to identification using frame descriptor extracted from selected representative frames within a scene segmentation. The proposed algorithm shows high success rate and low false alarm rate. In addition, the matching speed of this descriptor is very fast, we confirm this algorithm can be useful to practical application.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.45 no.5
• /
• pp.21-27
• /
• 2008

Despite recent studies on development of pulse diagnosis systems and needs for commercializing them, the reproducibility is one of the most controversial issues as ever. Because the pulse pressure value, which is one of the important parameters to evaluate reproducibility, is very vulnerable to moving artifacts, the reproducibility can not be obtained easily. In this paper, we suggested a moving artefacts detection system for a pulse diagnosis system so that a pulse diagnosis system can be robust to theses kinds of artefacts by excluding the contaminated parts from the pulse wave signal to be analyzed. This moving artifacts detection system was designed to consist of a three-axis accelerometer, an electromyography amplifier and a two-axis tilt sensor. To assess the suitability of the system, we examined the characteristics of each sensor's output signals with regard to the three specific motions such as extension, flexion and rotation. And, we also examined the each sensor's response to the high-frequency and low-frequency moving artifacts while the pulse wave signal was acquired from a pressure sensor for the pulse diagnosis. From these results, we could find that the response to subject's motions would be reflected in electromyography signal first, in accelerometer signals and in tilt sensor sequently. And, the facts that a stable pulse wave can be acquired in two seconds after high frequency or low frequency motions ended, were also found. Consequently, based on these findings, we set up some rules on the moving artifacts detection and designed an algorithm which is fit for our moving artifacts detection system.

• Journal of The Korean Association of Information Education
• /
• v.19 no.4
• /
• pp.419-430
• /
• 2015

This paper provides a database about the IPTV VOD usage behavior of children as well as mother's perception at home. We analyzed the correlation of mother's background with IPTV VOD using time of children through a survey. We analyzed how does the mother's background influences usage time of IPTV VOD for children through a survey. The survey was conducted by 500 mothers who have two to seven years old children with IPTV users in Korea. Compilation of the data reveals that 1) 36.6% of the children have watched IPTV VOD for the first time at two years old, 93.4% have encountered by family members among them. 40.8% of users have played IPTV VOD for children four days a week and the main genre was the animation. 2) The main reason for watching VOD was by the needs of their children, but the 66% of mothers concern for an excessive level of watching. 3) educational background of mother and monthly house income were significantly correlated with the usage time of IPTV VOD for children.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.49 no.2
• /
• pp.113-121
• /
• 2012

In this paper, we proposed fast and efficient algorithm for detecting near-duplication based on content based retrieval in large scale video database. For handling large amounts of video easily, we split the video into small segment using scene change detection. In case of video services and copyright related business models, it is need to technology that detect near-duplicates, that longer matched video than to search video containing short part or a frame of original. To detect near-duplicate video, we proposed motion distribution and frame descriptor in a video segment. The motion distribution descriptor is constructed by obtaining motion vector from macro blocks during the video decoding process. When matching between descriptors, we use the motion distribution descriptor as filtering to improving matching speed. However, motion distribution has low discriminability. To improve discrimination, we decide to identification using frame descriptor extracted from selected representative frames within a scene segmentation. The proposed algorithm shows high success rate and low false alarm rate. In addition, the matching speed of this descriptor is very fast, we confirm this algorithm can be useful to practical application.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.33 no.2
• /
• pp.595-608
• /
• 2013

This paper is proposed the computation method of moored ship motion considering harbor resonance, and estimated that the harbor resonance have an effect on moored ship motion. The computation of harbor resonance was used CGWAVE model and the computation of moored sip motion was used the Green function method expressed by three dimensions. This method was verified with the field observation data of moored ship motion, and the application of actual harbor was investigated with wave field data and down time record data in Pohang New Harbor. The resonance periods in Pohang New Harbor that obtained from wave field data were 80, 33, 23, 8 minute, which are the long waves, and 42, 54, 60 second, which are the infra-gravity waves inside harbor slip. The simulated results of harbor resonance were corresponded with the wave field data. This study was investigated on 5,000 ton, 10,000 ton and 30,000 ton ship sized in Pier 8 of Pohang New Harbor that the harbor resonance has effect on moored ship motion from simulated results of ship motion in case of included resonance and excluded resonance. In case of included resonance, the ship motion have increased by 12~400 percent when compared with results of excluded resonance. We could find that the harbor resonance have still more an effect on the surge and heave motions of a large size ship and the roll and yaw motions of a small size ship.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2014.06a
• /
• pp.28-31
• /
• 2014

본 논문에서는 블랙박스 혹은 운전석에 장착된 카메라로부터 얻어진 차량 영상에 대한 영역별 수직 히스토그램 매칭 및 선형 회귀분석 모델(linear regression model)을 활용한 강건한 차량 운행 동영상의 안정화(video stabilization) 기법을 제안한다. 동영상 안정화 기법은 영상의 흔들림 보정뿐 아니라 동영상 내 강건한 특징점 추적 및 매칭을 위한 이전의 전처리 과정으로 적용된다. 일반적으로 촬영 과정에서 많은 떨림이 포함될 수 있는 야외 CCTV 영상이나 손으로 들고(hand-held) 촬영된 동영상에 대한 흔들림 보정 등에 적용되고 있으나 영상 내 특징점이 지속적으로 변하고 영상의 변화 정도가 매우 심한 차량 운행 동영상에서는 적용된 사례가 드물다. 본 연구에서는 일반적인 비디오 안정화 기술이 적용되기 어려운 차량 운행 동영상에 대하여 수직 투영 히스토그램 매칭 및 선형 회귀분석 모델 기반의 안정화 기법을 제안한다. 제안된 기법은 입력영상에 대한 영역별 수직 투영 히스토그램 매칭을 수행하고 선형 회귀모델을 통해 영상에 나타나는 수직 및 회전이동 변환을 선형 근사하여 시간 영역 상의 입력 영상에 대한 안정화를 달성한다. 제안 방법의 검증을 위해 블랙박스로 촬영된 실제 동영상에 동영상 안정화 기술을 적용하였으며, 운행 중 불규칙한 노면으로 인한 영상의 흔들림이 효과적으로 제거되는 것을 확인할 수 있었다.