• Journal of the Optical Society of Korea
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• 제20권6호
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• pp.678-685
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• 2016

The standard high-availability seamless redundancy (HSR) protocol utilizes duplicated frame copies of each sent frame for zero fail over time. This means that even in cases of a node or link failure, the destination node will receive at least one copy of the sent frame, resulting in no network downtime. However, the standard HSR is mostly based on the electrical signal connection inside the node, which leads to the production of considerable latency at each node due to frame processing. Therefore, in a large scale HSR ring network, the accumulated latencies become significant and can often restrict the mission-critical real-time application of HSR. In this paper, we present a novel design for optical HSR (OHSR) that uses beam splitting/combining techniques. The proposed OHSR passes the frames directly to adjacent nodes without frame processing at each node, thereby theoretically generating no latency in any node. Various simulations for network samples, made to validate the OHSR design and its performance, show that the OHSR outperforms the standard HSR.

• Structural Engineering and Mechanics
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• 제52권3호
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• pp.541-558
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• 2014

A 1/4-scale two-bay eight-storey reinforced concrete frame was tested on shaking table. Initial shaking table tests were carried out through a set of real seismic excitations to investigate the seismic behavior of the RC frame. Subsequently, the damaged frame was repaired using epoxy injection technique, and then subjected to the tests with the same records. The purpose of this study was to investigate experimentally the dynamic characteristics, cracking pattern and lateral inter-story stiffness of RC frames using epoxy injection technique. The test results indicate that epoxy-injection technique appears to be a satisfactory method for repairing earthquake-damaged structure.

• Structural Engineering and Mechanics
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• 제37권1호
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• pp.95-110
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• 2011

This paper presents a tri-uniform bond stress model for predicting the lap splice strength of reinforcing bar at the critical bond splitting failure. The proposed bond distribution model consists of three zones, namely, splitting zone, post-splitting zone and yielding zone. In each zone, the bond stress is assumed to be constant. The models for bond strength in each zone are adopted from previous studies. Combining the equilibrium, strain-slip relation and the bond strength model in each zone, the steel stress-slip model can be derived, which can be used in the nonlinear frame analysis of the column. The proposed model is applied to derive explicit equations for predicting the strength of the lap splice strengthened by fiber reinforced polymer (FRP) in both elastic and post-yield ranges. For design purpose, a procedure to calculate the required FRP thickness and the number of FRP sheets is also presented. A parametric investigation was conducted to study the relation between lap splice strength and lap splice length, number and thickness of FRP sheets and the ratio of concrete cover to bar diameter. The study shows that the lap splice strength can be enhanced by increasing one of these parameters: lap splice length, number or thickness of FRP sheets and concrete cover to bar diameter ratio. Verification of the model has been conducted using experimental data available in literature.

• 한국정보통신학회논문지
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• 제21권12호
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• pp.2279-2284
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• 2017

비면허 대역(Unlicensed)을 사용한 최근 무선통신이 증가하고 있으며 사용범위도 점차 넓어지고 있다. 비면허 대역은 통신 장비 간에 간섭을 용인하는 전재조건과 비면허통신 증가로 주파수 중첩과 간섭 현상이 증가하고 있다. 특히 2.4GHz 대역을 사용하는 블루투스, 무선랜, 무선식별 시스템(RFID)의 간섭 현상은 심각해지고 있다. 이러한 환경의 도심지에서는 무선 전송매체 상태가 간섭과 방해전파의 환경이 대부분일 것이다. 방해전파환경에서 효과적 전송을 할 수 있는 방법은 대략 2가지로 생각할 수 있다. 첫 번째는 IEEE 802.11의 RTS/CTS방식이 있고 두 번째로는 프레임 분할(fragmentation)방식이 있다. 본 논문에서는 방해전파 환경에서 일정크기 이상의 프레임을 전송할 경우 무선 환경의 간섭으로 전송이 어려워진다. 이러한 환경에서 신뢰성 전송과 효율적 전송을 하기 위해 프레임을 일정한 작은 단위로 분할하여 전송하여 효과적 전송과 신뢰성을 확보한 프레임분할 전송기법을 구현하여 확인하였다.

• 한국정보처리학회논문지
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• 제4권6호
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• pp.1601-1614
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• 1997

본 논문에서는 ATM-LAN 환경의 MOD 서버들로부터 클라이언트들에게 프레임 기반의 CM(Continuous Media) 데이터 스트림을 전송하기 위한 기술들을 제안한다. 여기서 프레임이란 CM의 디스플레이 단위를 의미한다. 세부적으로는 수송 계층과 IP 계층의 개입없이 애플리케이션과 AAL이 직접적으로 접속함으로써 ATM-Specific한 native ATM 서비스를 적용한다. 또한 네비게이션 서버를 통한 투명한 브라이징 메카니즘, 서버와 클라이언트들간의 PVC를 통한 세션 설정 과정, 애플리케이션과 AAL과 QoS 협상 및 예약 과정, MIU 사이즈를 초과하는 프레임들에 대한 쪼갬/붙임 알고리즘 등을 제안하고 실험 결과를 제시한다.

• 한국게임학회 논문지
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• 제13권4호
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• pp.25-34
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• 2013

3D 게임에서 충돌 탐지를 효과적으로 하기 위해 구성하는 공간 분할 트리는 분할 평면을 결정하는데 트리 밸런스와 분할 평면과 겹치는 폴리곤의 개수 등을 고려해야 한다. 본 논문에서는 3D 게임 공간 분할 트리에서 트리 빌드 조건에 대한 가중치를 제어하는 휴리스틱 알고리즘을 제안하였다. 가중치의 변화에 따라서 트리 빌드 시간, 분할 평면과 겹치는 폴리곤을 쪼갤 때 시각적 불일치를 유발할 수 있는 T-junction 의 제거 시간, 트리 밸런스에 따른 렌더링 속도(frame per second) 등을 3D 게임 시뮬레이션을 통하여 분석하였다.

• 대한건축학회논문집:계획계
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• 제34권8호
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• pp.59-67
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• 2018

In a state where ancient buildings was left a lot in the case of Korea, many parts do not remain the documentation, and there is a Kiwarisho lot in Japan, however, the present methods and tree split does not exist in the Korea. However, it is impossible to make a perfect building without splitting exact member when making a building. Thus will not be revealed simply by presumption that there is a similar way to wood comparatively far in Korea. Without a comparison of building dimensions and Korea calculation dimensions Kiwarisho In the first study about the proportionality of Korea, I do not know until now, other studies of the following documents which house a high approximation ratio and member size of Korea consider reason to have is impossible. View compared with respect to the axis of the building in the early stages of research first. In the case of Japan and Korea to form a tree frames in basic form that form the building, the shaft portion is easy to understand and easy compared in common is at most the shaft portion.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권6호
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• pp.3012-3028
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• 2017

In this paper, we propose a joint power control strategy for both the uplink and downlink transmission by considering the energy requirements of the user equipments' uplink data transmissions in data and energy integrated communication networks (DEINs). In DEINs, the base station (BS) adopts the power splitting (PS) aided simultaneous wireless information and power transfer (SWIPT) technique in the downlink (DL) transmissions, while the user equipments (UEs) carry out their own uplink (UL) transmissions by exploiting the energy harvested during the BS's DL transmissions. In our DEIN model, there are M UEs served by the BS in order to fulfil both of their DL and UL transmissions. The orthogonal frequency division multiple access (OFDMA) technique is adopted for supporting the simultaneous transmissions of multiple UEs. Furthermore, a transmission frame is divided into N time slots in the medium access control (MAC) layer. The mathematical model is established for maximizing the sum-throughput of the UEs' DL transmissions and for ensuring their fairness during a single transmission frame T, respectively. In order to achieve these goals, in each transmission frame T, we optimally allocate the BS's power for each subcarrier and the PS factor for each UE during a specific time slot. The original optimisation problems are transformed into convex forms, which can be perfectly solved by convex optimisation theories. Our numerical results compare the optimal results by conceiving the objective of maximising the sum-throughput and those by conceiving the objective of maximising the fair-throughput. Furthermore, our numerical results also reveal the inherent tradeoff between the DL and the UL transmissions.

• JSTS:Journal of Semiconductor Technology and Science
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• 제17권1호
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• pp.79-85
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• 2017

In this paper, several optimizations are proposed to enhance the quality of lane detection algorithms in automotive applications. Considering the diagonal directions of lanes, the proposed limited Hough transform newly introduces image-splitting and angle-limiting schemes that relax the number of possible angles at the line voting process. In addition, unnecessary edges along the horizontal and vertical directions are pre-defined and removed during the edge detection procedures, increasing the detecting accuracy remarkably. Simulation results shows that the proposed lane recognition algorithm achieves an accuracy of more than 90% and a computing speed of 92 frame/sec, which are superior to the results from the previous algorithms.

• 한국컴퓨터정보학회논문지
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• 제21권10호
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• pp.11-19
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• 2016

The size of a display is large, The form becoming various of that do not apply to previous methods of gaze tracking and if setup gaze-track-camera above display, can solve the problem of size or height of display. However, This method can not use of infrared illumination information of reflected cornea using previous methods. In this paper, Robust pupil detecting method for eye's occlusion, corner point of inner eye and center of pupil, and using the face pose information proposes a method for calculating the simply position of the gaze. In the proposed method, capture the frame for gaze tracking that according to position of person transform camera mode of wide or narrow angle. If detect the face exist in field of view(FOV) in wide mode of camera, transform narrow mode of camera calculating position of face. The frame captured in narrow mode of camera include gaze direction information of person in long distance. The method for calculating the gaze direction consist of face pose estimation and gaze direction calculating step. Face pose estimation is estimated by mapping between feature point of detected face and 3D model. To calculate gaze direction the first, perform ellipse detect using splitting from iris edge information of pupil and if occlusion of pupil, estimate position of pupil with deformable template. Then using center of pupil and corner point of inner eye, face pose information calculate gaze position at display. In the experiment, proposed gaze tracking algorithm in this paper solve the constraints that form of a display, to calculate effectively gaze direction of person in the long distance using single camera, demonstrate in experiments by distance.