• Title/Summary/Keyword: Offset algorithm

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Low-Complexity Watermarking into SAO Offsets for HEVC Videos

  • Wu, Xiangjian;Jo, Hyun-Ho;Sim, Donggyu
    • IEIE Transactions on Smart Processing and Computing
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    • v.5 no.4
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    • pp.243-249
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    • 2016
  • This paper proposes a new watermarking algorithm to embed watermarks in thr process of sample adaptive offsets (SAO) for high efficiency video coding (HEVC) compressed videos. The proposed method embeds two-bit watermark into the SAO offsets for each coding tree unit (CTU). To minimize visual quality degradation caused by embedding watermark, watermark bits are embedded into SAO offset depending on the SAO types of block. Furthermore, the embedded watermark can be extracted by simply adding four offsets and checking their least significant bits (LSB) at the decoder side. The experimental results show that the proposed method achieves 0.3% BD-rate increase without much visual quality degradation. Two-bit watermark for each CTU is embedded for more bit watermarking. In addition, the proposed method requires negligible computational load for watermark insertion and extraction.

Development of Smart Interface Board for Truck Scale Load Cell (Truck Scale 용 Load Cell의 Smart Interface Board 개발)

  • Park, Chan-Won;Park, Chong-Yeon;Hong, Jae-Yong;Choi, Gyu-Suk;An, Kwang-Hee
    • Journal of Industrial Technology
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    • v.15
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    • pp.83-91
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    • 1995
  • This paper presents the design of a smart A/D conversion interface used for measuring the load of a truck. Since the load-cell sensor to be used is very sensitive for weight variation, the interface board must have the low-drift and the A/D conversion for accuracy. A new integrator and comparator has been developed to reduce the offset voltage and the drift current of operational amplifiers and has been adapted into the interface board. Also, a software algorithm has been developed to obtain the stable and accrurate A/D conversion. This software includes a RS-485 communication program to control the interface, which gives a capability of backing-up the calibration data and transferring control data. The test and evaluation of the designed interface has been shown as having the better performance compared to the other types of existing weighing systems and sensor instruments.

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Numerical investigation of the gravity effect on the shape of natural supercavity

  • Pouraria, Hassan;Park, Warn-Gyu
    • 한국전산유체공학회:학술대회논문집
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    • 2011.05a
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    • pp.58-64
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    • 2011
  • The objective of this paper is to investigate the gravity effect on the shape characters of natural supercavity. A finite difference solver along with an implicit, dual time, preconditioned, three-dimensional algorithm has been used to solve the two-phase Navier Stokes equations. Numerical solutions were performed for natural supercavitating flow past a disk for different cavitation and Froud numbers. The numerical results were compared with corresponding analytical results in quantitative manner and it was found that the shape of supercavity was reasonably predicted Numerical results indicated that the gravity effect can induce the asymmetry of supercavity. The asymmetry was apparent when the froud number was smaller so that for constant cavitation number when we reduced the froud number the opt of the axis of supercavity increased. Moreover, for specific froud number a decrease in cavitation number resulted in an increase in the offset of the supercavity Numerical results revealed that for froud number greater than 25 the gravity effect is negligible.

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Investigation on Airflows in Abnormal Nasal Cavity with Adenoid Vegetation by Particle Image Velocimetry

  • Kim, Sung Kyun;Son, Young Rak
    • Journal of Mechanical Science and Technology
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    • v.18 no.10
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    • pp.1799-1808
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    • 2004
  • Knowledge of airflow characteristics in nasal cavity is essential to understand the physiological and pathological aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. Since the final goal of these works is their contribution to the diagnosisand treatment of nasal diseases, the next step on this topic is naturally studies for disordered nasal cavities. In this paper, as the first application, airflows in the normal and abnormal nasal cavities with adenoid vegetation are investigated experimentally by PIV, and comparisons of both cases are appreciated. Dense CT data and careful treatment of model surface under the ENT doctor's advice provide more sophisticatedcavity model. The CBC PIV algorithm with window offset is used for PIV flow analysis. Average and RMS distributions are obtained for inspirational and expirational nasal airflows. Airflow characteristics that are related with the abnormalities in nasal cavity are presented.

A Carrier-Based Pulse Width Modulation Method for Indirect Matrix Converters

  • Nguyen, Dinh-Tuyen;Lee, Hong-Hee;Chun, Tae-Won
    • Journal of Power Electronics
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    • v.12 no.3
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    • pp.448-457
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    • 2012
  • This paper proposes a carrier-based pulse width modulation (PWM) method to control an indirect matrix converter (IMC) by analyzing the relationship between the space vector PWM (SVPWM) and the carrier-based PWM. The complexity of the SVPWM method for an IMC can be reduced by using an equivalent carrier-based PWM method. The advantage of the proposed algorithm is its ability use only one symmetrical triangular carrier signal to generate the gate signals for all of the power switches in both the rectifier and inverter stages as compared to the conventional method where the carrier signal used in the rectifier stage is different from that of the inverter stage. In addition, by using a suitable offset voltage component in the modulation signals, the output voltage magnitude reaches 0.866 of the input voltage magnitude. Simulation and experimental results are provided in order to validate the proposed method.

Efficient Tool Path Generation of Compound Geometric Surface (복합기하곡면의 효율적인 공구경로 생성)

  • 한충규;이동주
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.04b
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    • pp.429-433
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    • 1995
  • Compound solid is maded for specially fixed object. A number of compound soild are devided as a unit germetric solid. The special case of rotation about an arbitrary axis makes according selection modelfor transformation. View plane and View region are estiblished for back face removal. After back-face removal eachedge is checked for point of intersection. The designing of of fset surface id maded and tool-path gernerted on the part surface. In tersection point is checked among the offset surfaces. The paper used an efficient algorithm for generating tool paths to apply a notion view volume. Through machining experiments with a 3-axis machining centre, the adequacy of the analysis was confirmed.

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Implementation of a Pole-Placement Self-Tuning Adaptive Controller for SCARA Robot Using TMS320C5X Chip (TMS320C5X칩을 사용한 스카라 로봇의 극점 배치 자기동조 적응제어기의 실현)

  • 배길호;한성현
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.11a
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    • pp.754-758
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    • 1996
  • This paper presents a new approach to the design of self-tuning adaptive control system that is robust to the changing dynamic configuration as well as to the load variation factors using Digital signal processors for robot manipulators. TMS320C50 is used in implementing real-time adaptive control algorithms to provide advanced performance for robot manipulator, In this paper, an adaptive control scheme is proposed in order to design the pole-placement self-tuning controller which can reject the offset due to any load disturbance without a detailed description of robot dynamics. Parameters of discrete-time difference model are estimated by the recursive least-square identification algorithm, and controller parameters we determined by the pole-placement method. Performance of self-tuning adaptive controller is illusrated by the simulation and experiment for a SCARA robot.

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Analysis on Kinematic Characteristics of a Machine Tool Parallel Manipulator Using Neural Network (신경망을 이용한 공작기계 병렬 매니퓰레이터의 기구학 특성 분석)

  • Lee, Je-Sub;Ko, Jun-Bin
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.17 no.3
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    • pp.1-7
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    • 2008
  • This paper describes the kinematics which is a new type of parallel manipulator, and the neural network is applied to solving the forward kinematics problem. The parallel manipulator called it as a Stewart platform has an easy and unique solution about the inverse kinematics. However, the forward kinematics is difficult to get a solution because of the lack of an efficient algorithm caused by its highly nonlinearity. This paper proposes the neural network scheme of an Newton-Raphson method alternatively. It is found that the neural network can be improved its accuracy by adjusting the offset of the obtained result.

Optimal Compensation of Dual Carrier Frequency Offsets for MISO-mode DVB-T2

  • Jeon, Eun-Sung;Seo, Jeong-Wook;Yang, Jang-Hoon;Paik, Jong-Ho;Kim, Dong-Ku
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.2
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    • pp.610-628
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    • 2012
  • Dual carrier frequency offsets (CFOs) occur in multiple-input single-output (MISO)-mode DVB-T2 systems, where signals are transmitted simultaneously from two distributed transmitters in a single frequency network (SFN). In this paper, we first derive an optimal compensation frequency for dual CFOs. We also propose an algorithm that optimizes the compensation frequency for the MISO-mode DVB-T2 application. Its performance is compared with the conventional scheme by using a full DVB-T2 simulator.

Phase-Locked Three-Dimensional Structures in the Cylinder Wake Observed from Cinematic PIV Data (Cinematic PIV에 의한 실린더 후류의 위상평균된 3차원 구조)

  • Sung, Jae-Yong;Park, Kang-Kuk;Yoo, Jung-Yul
    • Proceedings of the KSME Conference
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    • 2000.04b
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    • pp.661-666
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    • 2000
  • Near-wake flow field of a circular cylinder is studied by means of a cinematic PIV system with high sampling rate and large internal memory block. Experiments are conducted in a closed-cycle water tunnel system and a cross-correlation algorithm in conjunction with FFT (Fast Fourier Transform) analysis and an offset correlation technique is used for vector processing. With the help of very high sampling frequency compared to the shedding frequency, it is possible to obtain phase-averaged information of the three-dimensional wake, even though the shedding is not forced but natural. Phase-locked vortical structures observed simultaneously from the spanwise and cross-stream planes are displayed in the wake-transition regime where fine-scale secondary vortices have a spanwise wavelength or around one diameter. Spatial relations and temporal evolutions of the primary Karman vortex and the secondary vortex are also discussed schematically.

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