• Title/Summary/Keyword: vertical frame

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Lightweight Design of Brake Bracket for Composite Bogie Using Topology Optimization (위상 최적 설계를 통한 복합소재 대차프레임용 제동장치 브래킷의 경량화 연구)

  • Lee, Woo Geun;Kim, Jung Seok
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.39 no.3
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    • pp.283-289
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    • 2015
  • In this study, the lightweight design of a brake bracket for a composite bogie was studied by considering two brake bracket models with thicknesses of 12t and 9t, respectively. For achieving this goal, finite element analysis and topology optimization were conducted. Firstly, the largest cross-sectional areas of the vertical and horizontal plates of the brake bracket were selected as the design variables. As the constraint, the Z-axis displacement of the brake bracket was increased by 2.5 units from the initial displacement value. The minimum volume fraction of the design regions was chosen as the objective function. The full model comprised a composite bogie frame and brackets attached together. However, to reduce the analysis time, 1D beam elements were used instead of the composite bogie frame by ensuring its equivalence with the full model. The result revealed that the weights of the 12t and 9t models of the brake bracket were reduced to 60 kg and 31 kg, respectively.

Development of a finite Element Model for Studying the Occupant Behavior and Injury Coefficients of a Large-sized Truck (대형트럭 승객거동과 상해치 해석을 위한 유한요소모델의 개발)

  • O, Jae-Yun;Kim, Hak-Deok;Song, Ju-Hyeon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.8
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    • pp.1577-1584
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    • 2002
  • This paper develops a finite element model for studying the occupant behavior and injury cofficients of a large-sized cab-over type truck. Since it does not have a room to absorb collision energy and deformation in front of the passenger compartment the deformation is directly transmitted to the passenger compartment. Moreover, since its steering column is attached on the frame, severe deformation of the frame directly affects on the steering wheel's movement. Therefore, if the occupant behavior and injury coefficients analysis is performed using a finite element model developed based on a sled test, it is very difficult to expect acquiring satisfactory results. Thus, the finite element model developing in this paper is based on the frontal crash test in order to overcome the inherent problems of the sled test based model commonly used in the passenger car. The occupant behavior and injury coefficients analysis is performed using PAM-CRASH installed in super-computer SP2. In order to validate the reliability of the developed finite element model, a frontal crash test is carried out according to a test method used fur developing truck occupant's secondary safety system in european community and japan. That is, test vehicle's collision direction is vertical to the rigid barrier and collision velocity is 45kph. Thus, measured vehicle pulses at the lower parts of the left and right B-pilla., dummy chest and head deceleration profiles, HIC(head injury criterial) and CA(chest acceleration) values, and dummy behavior from the frontal crash test are compared to the analysis results to validate reliability of the developed model.

A PSNR Estimation Method Exploiting the Visual Rhythm for Reconstructed Video Frames at IPTV Set-top Box (비쥬얼리듬을 이용한 IPTV Set-top Box 재생영상에 대한 PSNR 추정 기법)

  • Kwon, Jae-Cheol;Suh, Chang-Ryul
    • Journal of Broadcast Engineering
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    • v.14 no.2
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    • pp.114-126
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    • 2009
  • In this paper, we propose a PSNR(peak-to-peak signal to noise ratio) estimation method exploiting visual rhythm information for the reconstructed video frames at the customer's STB(Set-top Box). Key idea is that we can estimate the PSNR by using VR(visual rhythm) information even though a VR consists of the pixels in a vertical direction of a 2D(2-dimensional) video frame, because VR is the 1D projected version of a 2D video frame approximately. Simulation results show that the estimated PSNR from VR information is closely related to the PSNR from 2D video frames. The advantages of the proposed scheme includes that it can monitor the video quality efficiently while minimizing the computation load of STB, and show the location, duration and occurrence count of severe picture degradation.

Design of H.264 Deblocking Filter for Low-Power Mobile Multimedia SoCs (저전력 휴대 멀티미디어 SoC를 위한 H.264 디블록킹 필터 설계)

  • Koo Jae-Il;Lee Seongsoo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.43 no.1 s.343
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    • pp.79-84
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    • 2006
  • This paper proposed a novel H.264 deblocking filter for low-power mobile multimedia SoCs. In H.264 deblocking filter, filtering can be skipped on some pixels when pixel value differences satisfy some specific conditions. Furthermore, whole filtering can be skipped when quantization parameter is less than 16. Based on these features, power consumption can be significantly reduced by shutting down deblocking filter partially or as a whole. The proposed deblocking filter can shut down partial or whole blocks with simple control circuits. Common hardware performs both horizontal filtering and vertical filtering. It was implemented in silicon chip using $0.35{\mu}m$ standard cell library technology. The gate count is about 20,000 gates. The maximum operation frequency is 108MHz. The maximum throughput is 30 frame/s with CCIR601 image format.

Experimental Study on Structural Behavior of Tapered non-compact Frame with Snug-tightened Conditions (밀착조임 볼트체결에 따른 판폭두께비가 큰 변단면 프레임의 구조성능에 관한 실험적 연구)

  • Chung, Kyung-Soo;Jeon, Bae-Ho;Park, Man-Woo;Do, Byung-Ho
    • Journal of Korean Society of Steel Construction
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    • v.24 no.3
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    • pp.257-265
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    • 2012
  • Current trends in steel construction include using tapered, non-compact sections to minimize the use of excess material as much as possible by choosing the cross-sections instead of the classical approach of using prismatic members. In addition, snug conditions, especially the end-plate type, have the advantage of incurring less construction costs and shorter assembly times as opposed to full pre-tensioned conditions. On the other hand, it is important to predict the collapse of the PEB system due to over-loading. Large-scale tests of tapered steel portal frames with non-compact sections were conducted. The primary test parameters included the bolt connection method and the loading condition (vertical and horizontal load). The test results on initial stiffness and load capacity were investigated. Furthermore, comparisons between the analytical and experimental data for load-displacement curves were initiated. In addition, we evaluated the applicability of a snug bolt for the PEB frame in the field.

Line Segments Extraction by using Chain Code Tracking of Edge Map from Aerial Images (항공영상으로부터 에지 맵의 체인코드 추적에 의한 선소추출)

  • Lee Kyu-won;Woo Dong-min
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.6
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    • pp.709-713
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    • 2005
  • A new algorithm is proposed for the extraction of line segments to construct 3D wire-frame models of building from the high-resolution aerial images. The purpose of this study Is the accurate and effective extraction of line segments, considering the problems such as discordance of lines and blurred edges existing in the conventional methods. Using the edge map extracted from aerial images, chain code tracking of edges was performed. Then, we extract the line segments considering the strength of edges and the direction of them. SUSAN (Smallest Uni-value Segment Assimilating Nucleus) algorithm proposed by Smith was used to extract an edge map. The proposed algorithm consists of 4 steps: removal of the horizontal, vertical and diagonal components of edges to reduce non-candidate point of line segments based on the chain code tracking of the edge map, removal of contiguous points, removal of the same angle points, and the extraction of the start and end points to be line segments. By comparing the proposed algorithm with Boldt algorithm, better results were obtained regarding the extraction of the representative line segments of buildings, having relatively less extraction of unnecessary line segments.

Annual Energy Performance Evaluation of Zero Energy House Using Metering Data (실측데이터를 이용한 에너지제로주택의 연간 에너지성능평가)

  • Lim, Hee-Won;Yoon, Jong-Ho;Shin, U-Cheul
    • KIEAE Journal
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    • v.16 no.3
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    • pp.113-119
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    • 2016
  • Purpose: In this study, we evaluate the annual energy performance of the detached house which was designed with the aim of zero energy. Method: The experimental house which was constructed in Gonju Chungnam in 2013, is the single family detached house of light weight wood frame with $100m^2$ of heating area. Thermal transmittance of roof (by ISO 10211) and building external walls are designed as $0.10W/m^2K$ and $0.14W/m^2$ respectively and low-e coating vacuum window glazing with PVC frame was installed. Also grid connected PV system and natural-circulation solar water heater was applied and 6kWp capacity of photovoltaic module was installed in pitched roof and $5m^2$ of solar collector in vertical wall facing the south. We analyzed the 2014 annual data of the detached house in which residents were actually living, measured though web-based remote monitoring system. Result: First, as a result, total annual energy consumption and energy production (PV generation and solar hot water) are 7,919kWh and 7,689kWh respectively and the rate of energy independence is 97.1% which is almost close to the zero energy. Second, plug load and hot water of energy consumption by category showed the highest numbers each with 33% and 31%, with following space heating 24%, electric cooker 8%, lighting 3% in order. Hot water supply is relatively higher than space heating because high insulation makes it decreased.

Study on News Video Character Extraction and Recognition (뉴스 비디오 자막 추출 및 인식 기법에 관한 연구)

  • 김종열;김성섭;문영식
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.40 no.1
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    • pp.10-19
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    • 2003
  • Caption information in news videos can be useful for video indexing and retrieval since it usually suggests or implies the contents of the video very well. In this paper, a new algorithm for extracting and recognizing characters from news video is proposed, without a priori knowledge such as font type, color, size of character. In the process of text region extraction, in order to improve the recognition rate for videos with complex background at low resolution, continuous frames with identical text regions are automatically detected to compose an average frame. The image of the averaged frame is projected to horizontal and vertical direction, and we apply region filling to remove backgrounds to produce the character. Then, K-means color clustering is applied to remove remaining backgrounds to produce the final text image. In the process of character recognition, simple features such as white run and zero-one transition from the center, are extracted from unknown characters. These feature are compared with the pre-composed character feature set to recognize the characters. Experimental results tested on various news videos show that the proposed method is superior in terms of caption extraction ability and character recognition rate.

ASIC Design of Wavelet Transform Filter for Moving Picture (동영상용 웨이브렛 변환 필터의 ASIC 설계)

  • Kang, Bong-Hoon;Lee, Ho-Joon;Koh, Hyung-Hwa
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.12
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    • pp.67-75
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    • 1999
  • In this paper, we present an ASIC(Application Specific Integrated Circuit) design of wavelet transform filter Wavelet transform is used in lots of application fields which include image compression, because it has an excellent energy compaction. The operation characteristic and performance of wavelet transform filter are analyzed by using verilog-HDL(Hardware Description Language). In this paper, the designed wavelet transform filter uses line memory to improve data processing rate. Generally, when it reads and writes data of DRAM by using Fast Page Mode, input and output processing is very fast in horizontal direction but substantially slow in vertical direction. The use of line memory solves this low speed processing problem. As a result, though the size of the chip is getting larger, processing time for an image frame becomes 4.66ms. Generally, since the limit of 1 frame processing time on the data of TV video is 33ms, so it is appropriate for TV video.

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Determination of Precise Coordinates and Velocities of 142 International GNSS Service Stations to Realize Terrestrial Reference System (지구기준계 실현을 위한 142개 IGS 관측소 정밀좌표 및 속도 결정)

  • Baek, Jeong-Ho;Jung, Sung-Wook;Shin, Young-Hong;Cho, Jung-Ho;Park, Pil-Ho
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.27 no.3
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    • pp.303-310
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    • 2009
  • We processed seven years data of 142 IGS(International GNSS Service) stations were processed, which have been selected with an optimal network algorithm, to realize terrestrial reference system. To verify the result, a comparison with the ITRF2005 was given both in positions and velocities with transformation parameters estimation. The transformation parameters are within 4.3 mm in length, while the RMS(root mean square) difference of positions and velocities are 6.7 mm and 1.3 mm/yr in horizontal and 13.3 mm and 2.4 mm/yr in vertical, respectively, which represent good coincidences with ITRF2005. This research would help developing our own geodetic reference frame and may be applied for the global earth observations such as the global tectonics. A further improved TRF would be expected by applying various data processing strategies and with extension of data in number and observation period.