• Title/Summary/Keyword: Design of a Block

Search Result 2,670, Processing Time 0.054 seconds

Troubles and Countermeasures of Geogrid-Reinforced Earth Wall (지오그리드 보강토 옹벽의 설계/시공에 따른 문제점과 대책방안)

  • 조삼덕
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2001.10a
    • /
    • pp.315-321
    • /
    • 2001
  • Since 1984, block-type reinforced earth wall with geogrid reinforcement has been widely used for retaining wall applications till now in Korea. The use of geogrid as a reinforcement in the reinforced earth wall is steadily increased in an amount over 1,500,000㎡ in a year However, still need exists that some problems in design and construction practices should be made to review, Therefore, this paper reviewed reasonable criteria for selection of backfills, design details considering the effect of the upper soil slope on reinforced earth wall, horizontal displacement of facing block during compaction, and the damage of geogrid reinforcements on the edge part of facing block. Finally, alternative methods of measures on those problems are proposed.

  • PDF

Improved ABAB Type Quasi-orthogonal Space-Time Block Codes (개선된 ABAB 형 준직교 시공간 블록 부호)

  • Kim, Chang-Joong;Yeo, Seung-Jun;Lee, Ho-Kyoung
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.46 no.4
    • /
    • pp.70-76
    • /
    • 2009
  • In this paper, we propose the design criteria of the pre-processing scheme used in ABAB type quasi-orthogonal space-time block code(QOSTBC) and derive. The proposed design criteria show how to obtain full-diversity and full-rate (FDFR) property, single-symbol decodability, and increased coding gam. We design an improved ABAB type QOSTBC using the proposed design criteria. The desinged QOSTBC has a superior performance to Dalton's QOSTBC and inherits the merits of Dalton's QOSTBC, which are FDFR property, and single symbol decodability for PAM signal constellation.

An Efficient Inter-Prediction Hardware Design for the H.264/AVC Decoder (H.264/AVC 디코더를 위한 효율적인 인터 예측 하드웨어 구조 설계)

  • Jin, Xianzhe;Ryoo, Kwangki
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2009.05a
    • /
    • pp.112-115
    • /
    • 2009
  • Inter-Prediction is always the main bottleneck in H.264/AVC Baseline Profile. This paper describes an efficient Inter-Prediction hardware architecture design. H.264/AVC decoder supports various block types such as $16{\times}16$, $16{\times}8$, $8{\times}16$, $8{\times}8$, $8{\times}4$, $4{\times}8$, $4{\times}4$ block types. Reference Software(JM) only considers the $4{\times}4$ block type when the reference block is being fetched. This causes duplicated pixels which needs extra fetch cycles. In order to eliminate some of the duplicated pixels, the $8{\times}8$ and $4{\times}4$ block types were considered in the previous design. If the block size is larger than or equal to the $8{\times}8$ block type, it will be separated into several $8{\times}8$ block types and if the block size is smaller than the $8{\times}8$ block type it will be separated into several $4{\times}4$ blocks. For further reduction of the fetch cycles, the various block types are considered in this paper. As a result, the maximum cycle reduction percentage is 18.6% comparing with the previous design.

  • PDF

A Study on Structural Improvement of the Swashplate Axial Piston Pump Valve Block (2) (사판 식 축 피스톤 펌프 밸브블록의 구조개선에 관한 연구(2))

  • Kim, Jeong-Hwa;Shin, Mi-Jung;Kim, Myung-Kyu
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.17 no.1
    • /
    • pp.76-81
    • /
    • 2018
  • This study aims to provide ways to achieve structural improvements of the internal flow path of the discharge plenum of a swash plate piston pump valve block vulnerable to cracks. This paper corresponds to Part II, which consists of a structural interpretation of the internal flow path of the discharge plenum of the valve block. The simple model result reviewed in Part I was incorporated into the valve block model and five different design changes were reviewed as part of the study on the structural improvement of the internal flow path of the valve block.

Reinforcement design for the anchorage of externally prestressed bridges with "tensile stress region"

  • Liu, C.;Xu, D.;Jung, B.;Morgenthal, G.
    • Computers and Concrete
    • /
    • v.11 no.5
    • /
    • pp.383-397
    • /
    • 2013
  • Two-dimensional tensile stresses are occurring at the back of the anchorage of the tendons of prestressed concrete bridges. A new method named "tensile stress region" for the design of the reinforcement is presented in this paper. The basic idea of this approach is the division of an anchor block into several slices, which are described by the tensile stress region. The orthogonal reinforcing wire mesh can be designed in each slice to resist the tensile stresses. Additionally the sum of the depth of every slice defined by the tensile stress region is used to control the required length of the longitudinal reinforcement bars. An example for the reinforcement design of an anchorage block of an external prestressed concrete bridge is analyzed by means of the new presented method and a finite element model is established to compare the results. Furthermore the influence of the transverse and vertical prestressing on the ordinary reinforcement design is taken into account. The results show that the amount of reinforcement bars at the anchorage block is influenced by the layout of the transverse and the vertical prestressing tendons. Using the "tensile stress region" method, the ordinary reinforcement bars can be designed more precisely compared to the design codes, and arranged according to the stress state in every slice.

Fast Binary Block Inverse Jacket Transform

  • Lee Moon-Ho;Zhang Xiao-Dong;Pokhrel Subash Shree;Choe Chang-Hui;Hwang Gi-Yean
    • Journal of electromagnetic engineering and science
    • /
    • v.6 no.4
    • /
    • pp.244-252
    • /
    • 2006
  • A block Jacket transform and. its block inverse Jacket transformn have recently been reported in the paper 'Fast block inverse Jacket transform'. But the multiplication of the block Jacket transform and the corresponding block inverse Jacket transform is not equal to the identity transform, which does not conform to the mathematical rule. In this paper, new binary block Jacket transforms and the corresponding binary block inverse Jacket transforms of orders $N=2^k,\;3^k\;and\;5^k$ for integer values k are proposed and the mathematical proofs are also presented. With the aid of the Kronecker product of the lower order Jacket matrix and the identity matrix, the fast algorithms for realizing these transforms are obtained. Due to the simple inverse, fast algorithm and prime based $P^k$ order of proposed binary block inverse Jacket transform, it can be applied in communications such as space time block code design, signal processing, LDPC coding and information theory. Application of circular permutation matrix(CPM) binary low density quasi block Jacket matrix is also introduced in this paper which is useful in coding theory.

Overall Performance characteristic for 300MW Taean IGCC Plant (300MW 태안 IGCC 플랜트 종합성능 특성)

  • Kim, Hakyong;Kim, Jaehwan
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2010.11a
    • /
    • pp.129.2-129.2
    • /
    • 2010
  • As a part of the government renewable energy policy, KOWEPO is constructing 300MW IGCC plant in Taean. IGCC plant consists of gasification block, air separation unit and power block, which performance test is separately conducted. Overall performance test for IGCC plant is peformed to comply with ASME PTC 46. Major factors affected on the overall efficiency for IGCC plant are external conditions, each block performance(gasification, ASU, power block), water/steam integration and air integration. Performance parameters of IGCC plant are cold gas efficiency, oxygen consumption, sensible heat recovery of syngas cooler for gasification block and purity of oxygen, flow amount of oxygen and nitrogen, power consumption for air separation unit and steam/water integration among the each block. The gas turbine capacity applied to the IGCC plant is 20 percent higher than NGCC gas turbine due to the low caloric heating value of syngas, therefor it is possible to utilize air integration between gas turbine and air separation unit to improve overall efficiency of the IGCC plant and there is a little impact on the ambient condition. It is very important to optimize the air integration design with consideration to the optimized integration ratio and the reliable operation. Optimized steam/water integration between power block and gasification block can improve overall efficiency of IGCC plant where the optimized heat recovery from gasification block should be considered. Finally, It is possibile to achieve the target efficiency above 42 percent(HHV, Net) for 300MW Taean IGCC plant by optimized design and integration.

  • PDF

A Single-Chip Video/Audio CODEC for Low Bit Rate Application

  • Park, Seong-Mo;Kim, Seong-Min;Kim, Ig-Kyun;Byun, Kyung-Jin;Cha, Jin-Jong;Cho, Han-Jin
    • ETRI Journal
    • /
    • v.22 no.1
    • /
    • pp.20-29
    • /
    • 2000
  • In this paper, we present a design of video and audio single chip encoder/decoder for portable multimedia application. The single-chip called as video audio signal processor (VASP) consists of a video signal processing block and an audio single processing block. This chip has mixed hardware/software architecture to combine performance and flexibility. We designed the chip by partitioning between video and audio block. The video signal processing block was designed to implement hardware solution of pixel input/output, full pixel motion estimation, half pixel motion estimation, discrete cosine transform, quantization, run length coding, host interface, and 16 bits RISC type internal controller. The audio signal processing block is implemented with software solution using a 16 bits fixed point DSP. This chip contains 142,300 gates, 22 Kbits FIFO, 107 kbits SRAM, and 556 kbits ROM, and the chip size is $9.02mm{\times}9.06mm$ which is fabricated using 0.5 micron 3-layer metal CMOS technology.

  • PDF

A Study on The State Estimation of The Time-Invariant Linear Systems via The Improved Parameter Estimation Method for The Block Pulse Coefficients (개선된 블록 펄스 계수 추정 기법을 이용한 선형 시불변계의 상태 추정에 관한 연구)

  • Kim, Tai-Hoon;Kim, Jin-Tae;Chung, Je-Wook;Sim, Jae-Seon
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • v.51 no.4
    • /
    • pp.137-143
    • /
    • 2002
  • Because Block Pulse functions are used in a variety of fields such as the analysis and controller design of systems, it is necessary to find the more exact value of the Block Pulse series coefficients. This paper presents a method for the state estimation of the time-invariant linear systems via the improved estimation method for the Block Pulse coefficients by using the Simpson's rule. The proposed method using the Simpson's rule improve the accuracy of the Block Pulse coefficients.