• Title/Summary/Keyword: compression delay time

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A Comparative study on Dynamic & Static elastic modulus of cement mortar specimens (시멘트 모르타르 재료의 동탄성계수와 정탄성계수 비교 연구)

  • O, Seon-Hwan;Kim, Hyoung-Soo;Jang, Bo-An;Suh, Man-Cheol
    • Journal of the Korean Geophysical Society
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    • v.3 no.2
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    • pp.127-138
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    • 2000
  • This study was conducted to examine the differences between dynamic and static elastic constants by use of some laboratory tests of cement mortar specimens which have different water/cement mixing ratios. Specific gravity measurement, ultrasonic velocity estimating and uniaxial compression test were adopted to acquire the dynamic and static elastic constants. Digital data acquisition and processing enhanced the accuracy of estimating the velocities of specimens drastically, Also, the method using the gradient of propagation delay time in according to increment of specimen length more enhanced the accuracy than the method using the only one specimen length over total propagation time. The correlation between density and the P and S wave velocity of specimens shows reliable positive relation and the correlation between density and the strength of uniaxial compression has the similar relationship. The dynamic Young's modulus $(E_D)$ is alway greater than the static Young's modulus $(E_S)$ and there is increasing tendency of the ratio $(E_D/E_S)$ according to the increase of density or strength of the specimens. On the other hand, there is no typical relationship between dynamic Poisson's ratio $({\nu}_D)$ and static Poisson's ratio $({\nu}_S)$ and just the ratio of ${\nu}_D/{\nu}_S$ ranges front 69 to 122 %.

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A Low Cost Instruction Set for Bit Stream Process (비트열 처리를 위한 저비용 명령어 세트)

  • Ham, Dong-Hyeon;Lee, Hyoung-Pyo;Lee, Yong-Surk
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.45 no.2
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    • pp.41-47
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    • 2008
  • Most of media compression CODECs adopts the variable length coding method. This paper proposes special registers and instruction set for bit stream process in order to accelerate the decoding process of the variable length code. The instruction set shares the conventional data path to minimize additional costs. And bit stream is read from the memory instead of the special port. Therefore the instruction set minimizes the change of the processor, and is adopted without any additional input controller and buffer, and accelerate decoding process of variable length code. The data path of the instruction set needs additional 65 bits memory and 344 equivalent gates, 0.19 ns delay under TSMC $0.25{\mu}m$ technology. The instruction set reduced the execution time of the variable length code decoding process in H.264/AVC by about 55%.

Design of High Speed Binary Arithmetic Encoder for CABAC Encoder (CABAC 부호화기를 위한 고속 이진 산술 부호화기의 설계)

  • Park, Seungyong;Jo, Hyungu;Ryoo, Kwangki
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.4
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    • pp.774-780
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    • 2017
  • This paper proposes an efficient binary arithmetic encoder hardware architecture for CABAC encoding, which is an entropy coding method of HEVC. CABAC is an entropy coding method that is used in HEVC standard. Entropy coding removes statistical redundancy and supports a high compression ratio of images. However, the binary arithmetic encoder causes a delay in real time processing and parallel processing is difficult because of the high dependency between data. The operation of the proposed CABAC BAE hardware structure is to separate the renormalization and process the conventional iterative algorithm in parallel. The new scheme was designed as a four-stage pipeline structure that can reduce critical path optimally. The proposed CABAC BAE hardware architecture was designed with Verilog HDL and implemented in 65nm technology. Its gate count is 8.07K and maximum operating speed of 769MHz. It processes the four bin per clock cycle. Maximum processing speed increased by 26% from existing hardware architectures.

Dynamic behavior of SRC columns with built-in cross-shaped steels subjected to lateral impact

  • Liu, Yanhua;Zeng, Lei;Liu, Changjun;Mo, Jinxu;Chen, Buqing
    • Structural Engineering and Mechanics
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    • v.76 no.4
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    • pp.465-477
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    • 2020
  • This paper presents an investigation on the dynamic behavior of SRC columns with built-in cross-shaped steels under impact load. Seven 1/2 scaled SRC specimens were subjected to low-speed impact by a gravity drop hammer test system. Three main parameters, including the lateral impact height, the axial compression ratios and the stirrup spacing, were considered in the response analysis of the specimens. The failure mode, deformation, the absorbed energy of columns, as well as impact loads are discussed. The results are mainly characterized by bending-shear failure, meanwhile specimens can maintain an acceptable integrity. More than 33% of the input impact energy is dissipated, which demonstrates its excellent impact resistance. As the impact height increases, the flexural cracks and shear cracks observed on the surface of specimens were denser and wider. The recorded time-history of impact force and mid-span displacement confirmed the three stages of relative movement between the hammer and the column. Additionally, the displacements had a notable delay compared to the rapid changes observed in the measured impact load. The deflection of the mid-span did not exceed 5.90mm while the impact load reached peak value. The impact resistance of the specimen can be improved by proper design for stirrup ratios and increasing the axial load. However, the cracking and spalling of the concrete cover at the impact point was obvious with the increasing in stiffness.

A Design of Pipelined-parallel CABAC Decoder Adaptive to HEVC Syntax Elements (HEVC 구문요소에 적응적인 파이프라인-병렬 CABAC 복호화기 설계)

  • Bae, Bong-Hee;Kong, Jin-Hyeung
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.5
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    • pp.155-164
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    • 2015
  • This paper describes a design and implementation of CABAC decoder, which would handle HEVC syntax elements in adaptively pipelined-parallel computation manner. Even though CABAC offers the high compression rate, it is limited in decoding performance due to context-based sequential computation, and strong data dependency between context models, as well as decoding procedure bin by bin. In order to enhance the decoding computation of HEVC CABAC, the flag-type syntax elements are adaptively pipelined by precomputing consecutive flag-type ones; and multi-bin syntax elements are decoded by processing bins in parallel up to three. Further, in order to accelerate Binary Arithmetic Decoder by reducing the critical path delay, the update and renormalization of context modeling are precomputed parallel for the cases of LPS as well as MPS, and then the context modeling renewal is selected by the precedent decoding result. It is simulated that the new HEVC CABAC architecture could achieve the max. performance of 1.01 bins/cycle, which is two times faster with respect to the conventional approach. In ASIC design with 65nm library, the CABAC architecture would handle 224 Mbins/sec, which could decode QFHD HEVC video data in real time.

A Study on Vocal EQ'ing Method (Vocal EQ'ing 방법에 관한 연구)

  • Kim, Minju
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.12
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    • pp.569-573
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    • 2018
  • Music is composed of the sound of many instruments. Among them, the sound of the human voice naturally stands out to us and immediately connects with the listener. However, A lot of different steps go into perfectly mixing a vocal, but I'm going to focus on the most important step, equalization. In this paper, starting with the concept and the type of EQ for the requirements associated with the EQ's work and will know about when and how to use subtractive EQ, additive EQ during the recording and mixing process. EQ is one if the most important tools for mixing, especially when dealing with vocals. The control that EQ's offer allows you work, boosting and cutting to fit the vocal perfectly into the mix. The key to get a professional sounding vocal every time is to always keep in mind what you're trying to achieve stylistically and for it, using reference track is very effective. In addition to EQing, there are a variety of complex working steps such as compression, reverb, chorus, delay, adjusted for the effects of the work and harmonies of backing vocals and that are also very important task. The work of EQing is the beginning of the mixing process, among other things, need to be a detailed work throughout the consideration of the above points to its importance is greater relationship.