• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.7
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• pp.2213-2222
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• 1996

This paper presents the design process and evaluaation results of a two-axis force transducer for measuring flange reaction forces. A double-cantilever beam structure is used as a sensing element, and its optimal configuration is determined based on the derived strain equations to maximize the sensitivity and minimize the regid body displacements. To reduce the coupling errors between two-axis forces, strain distributions by finite elemetns analysis are utilized and the Wheaststone bridge cricuits composed of strain gages are built such that the output voltage should be zero, although strains of four strain gages are not zero. Calibration test shows that the two-azxis force transducer developed in this paper is useful in measuring flange reaction forces within the coupling error of 5.53%.

• Journal of Internet Computing and Services
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• v.3 no.2
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• pp.69-77
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• 2002

Recently, Digital video is one of the important information media delivered on the Internet and playing an increasingly important role in multimedia. This paper proposes a Video Browsing Service(VBS) that provides both the video content retrieval and the video browsing by the real-time user interface on Web, For the scene segmentation and key frame extraction of video sequence, we proposes an efficient scene change detection method that combines the RGB color histogram with the $x^2$(Chi Square) histogram. Resulting key frames are linked by both physical and logical indexing, This system involves the video editing and retrieval function of a VCR's, Three elements that are the date, the field and the subject are used for video browsing. A Video Browsing Service is implemented with MySQL, PHP and JMF under Apache Web Server.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.11a
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• pp.58-61
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• 2011

방송 콘텐츠 제작에는 카메라, VCR, NLE, 인코더 등의 장비가 사용되고 있으며, VCR 헤더 불량, 테이프 노후화/보관불량, NLE 편집 오류, 인코더 장비 불량 등의 다양한 이유로 콘텐츠에 예기치 않은 비디오 및 오디오 오류가 발생할 수 있다. 이러한 문제점을 해결하기 위하여 콘텐츠에 포함된 다양한 비디오 및 오디오 오류를 자동으로 검사할 수 있는 자동 검사 시스템이 요구된다. 본 논문에서는 이러한 다양한 오류를 자동으로 검사할 수 있는 방법 중 특히 비디오 내에 종종 포함되는 블록 오류를 대상으로 하는 고속 오류 검출 방법을 설명한다. 제안한 방법은 비디오 내의 매 프레임의 코너 수를 계산하고, 시간 증가에 따른 코너 수의 변화량을 검사하여 블록 오류가 포함될 것으로 예상되는 후보 프레임을 찾는 1단계 과정과, 후보 프레임을 대상으로 Adaboost 인식 기술을 사용하여 학습한 분류기를 통해 최종 블록 오류가 포함된 프레임을 검출하는 2단계 과정으로 구성된다. 시스템 구현 실험 결과, 비디오 내에 포함된 블록 오류를 프레임 단위로 정확하게 고속 검출 하는 것이 가능함을 확인하였다. SD급의 경우 실시간 대비 2.3배속 가량의 고속 검사가 가능하고 HD의 경우에도 0.8배속 수준의 고속 검사가 가능하였다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.5 no.1
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• pp.73-83
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• 1993

Thermodynamic properties of alternatives for R12 and R22 were estimated and performances of refrigerating cycle using these refrigerants were compared. In this study, we adopt R134a, R22/R142b, R22/R152a, R22/R152a/R124 as alternatives for R12 and R32/R134a for R22. Thermodynamic properties of these refrigerants were estimated using modified CSD equation of state. Cycle simulations of the refrigerating system considering heat source were carried out in order to compare the performance of the system. R134a shows relatively lower COP than R12 but very similar VCR. R22/R142b(50/50 mass fraction), R22/R152a(10/90), R22/R152a/R124(30/25/45) are good for the substitutes of R12 and R32/R134a(30/70) is appropriate for that of R22 in view of COP and VCR.

• Journal of Korean Neurosurgical Society
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• v.61 no.2
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• pp.251-257
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• 2018

Objective : The aim of this study was to investigate clinical and radiological outcomes of patients who underwent posterior vertebral column resection (PVCR) by a single neurosurgeon in a single institution. Methods : Thirty-four consecutive patients with severe spinal deformities who underwent PVCR between 2010 and 2016 were enrolled. The radiographic measurements included a kyphotic angle of PVCR levels (VCR angle), sagittal vertical axis (SVA), thoracic kyphosis, lumbar lordosis (LL), and spinopelvic parameters. The data of surgical time, estimated blood loss, duration of hospital stay, complications, intraoperative neurophysiologic monitoring, and the Scoliosis Research Society (SRS)-22 questionnaire were collected using a retrospective review of medical records. Results : The VCR angle, LL, and SVA values were significantly corrected after surgery. The VCR and LL angle were changed from the average of $38.4{\pm}32.1^{\circ}$ and $-22.1{\pm}39.1^{\circ}$ to $-1.7{\pm}29.4^{\circ}$ (p<0.001) and $-46.3{\pm}23.8^{\circ}$ (p=0.001), respectively. The SVA was significantly reduced from $103.6{\pm}88.5mm$ to $22.0{\pm}46.3mm$ (p=0.001). The clinical results using SRS-22 survey improved from $2.6{\pm}0.9$ to $3.4{\pm}0.8$ (p=0.033). There were no death and permanent neurological deficits after PVCR. However, complications occurred in 19 (55.9%) patients. Those patients experienced a total of 31 complications during- and after surgery. Sixteen reoperations were performed in twelve (35.3%) patients. The incidence of transient neurological deterioration was 5.9% (two out of 34 patients). Conclusion : Severe spinal deformities can be effectively corrected by PVCR. However, the PVCR technique should be utilized limitedly because surgery-related serious complications are relatively common.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.9B
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• pp.1643-1651
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• 1999

Video-On-Demand (VOD) is expected to provide the user with interactive operations such as VCR functions. In particular, fast scan functions like “Fast Forward” of “Fast Backward” for a certain speedup playback are required. Since they require a significant amount of system resources, schemes to reduce bandwidth requirements for the network or disk are needed. In MPEG standard, Group-of-Pictures (GoP) is a random access unit which can be decoded independently. Since storing and transmitting a video stream based on GoP is efficient, it is practical to support fast scan functions based on GoP. In this paper, we present a dynamic transmission scheduling scheme to support fast scan functions with m-times normal playback rate for a stored video. The proposed scheme writes a transmission schedule whenever user requests a fast scan function. That is, the scheme constructs the data set to be smoothed by skipping GoPs according to a given speedup factor, and then writes the transmission schedule by applying a bandwidth smoothing. Finally, the scheme restarts the transmission of video data to a client according to the new schedule. The proposed scheme results in speeding up the playback rate by utilizing “GoP skipping”, and then reduces the computational overhead by applying a bandwidth smoothing based on GoP.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.655-664
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• 2013

The Korean film has not been on the board of Korean waves due to the limitation of the media accessibility. However, N-screen gives Korean films the chance of being on the board of Korean waves, especially in Asian country which have shared cultural codes. This study aims to demonstrate the possibility of Korean films in asia based on the analysis of Korean film viewers' motivation and media usage. For this purpose the 330 data were collected among Korean, Japanese and Chinese from Feb, 23rd through April, 5th in 2013. The results show the followings; 1) Korean viewers have the strong preference of cinema theater to other media such as PC, VCR/DVD player, tablet PC and mobile phones. Whereas, Japanese viewers prefer VCR or DVD players and Chinese viewers prefer PC and mobile phones. 2) In terms of viewing motivation, social utility is most important to Korean viewers while diversion to Japanese and Chinese viewers.

• Review of KIISC
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• v.20 no.3
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• pp.24-30
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• 2010

영상보안시스템의 저장 장치는 초기의 아날로그 방식인 VCR에서 디지털 방식인 DVR로 넘어오면서 급격한 기술 개발과 성능 개선이 이루어진데 이어 현재에도 해상도, 적용된 압축코덱, Interface 등의 부분에서 기술의 발전 및 변화의 흐름이 지속되고 있다. 특히 최근에는 다양한 요인으로 인한 영상보안시스템의 HD 전환과 실질적인 지능형 영상보안시스템 구현을 위한 새로운 기술이 요구되고 있으며 그에 기반한 기술적인 변화와 발전이 점차 이루어지고 있다. 본 논문에서는 최근의 핵심적인 DVR 기술동향과 함께 앞으로의 DVR 전망에 대해서 살펴보고자 한다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.631-633
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• 2000

Modern consumer electronic products like TV, VCR etc, offer users the convience of switching the equipment on and off via a remote control handset. When this type of equipments is switched off, it is said to be in standby mode. In this paper, We proposed that the method of the blocking standby power Son in industrial product including electronic and electronic appliauces. This method is perfectly blocking the standby power of electrical circuit.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11b
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• pp.503-507
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• 2003

사용자의 고화질 요구와 사업자의 차별화된 서비스 제공 노력의 결과로 기존의 MPEG-4 기반이 아닌 고화질 전용의 MPEG-2 화질을 사용하는 VOD 서비스가 새로운 대안으로 제시되고 있다. MPEG-2 비디오는 높은 네트워크 대역폭을 요구하는 단점이 있는 반면, 사용자에게 양질의 화질을 제공할 수 있으며 표준의 사용으로 컨텐츠 유지. 보수에 유리하다. 본 논문에서는 상용 스트리밍 서버인 nCUBE 서버와 연동하여 MPEG-2 TS 데이터를 스트리밍 하는 VOD 시스템에 대하여 설명한다. VOD 제어 프로토콜로 RTSP(Real Time Streaming Protocol)를 사용하였으며, 스트림 전송 프로토콜로 UDP/IP 방식을 사용하였다. 지원하는 VCR 기능으로는 FF, RW, STOP. Pause가 있다.