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We consider a distributed lighting control system with multiple networked luminaires, each equipped with a light and presence sensor, and a local controller. Using local sensor inputs and information exchange with limited neighboring controllers, each local controller determines the optimum dimming level of its luminaire so that the lighting power consumption is minimized. This is done under net illumination...
Self-calibration based on rotating cameras is a classical technique for recovering internal parameters which ensures that the camera motion is pure rotation and does not permit translation. In practice, however, it is hard to exactly keep the camera not to translate. Previous studies on this issue are mainly qualitative and less operable for practice applications. In this paper, we experimentally...
Recently, autonomous robots have been widely used in the production field. There are several advantages to introducing industrial robots in factories. However, these robots cannot be used in unknown environments because most of them are controlled by sequence controls. Two cameras are used as vision sensors that can recognize the outside environment to solve this problem. In this study, we aim at...
Although numerous steganalyzers for least significant bit (LSB) matching have been presented, the detection for uncompressed images and low embedding rates remains challenge for steganalysts. In this paper, we propose a novel method for detection of LSB matching steganography, which is based on the features extracted from a conditional probability matrix described by Markov Mesh Models (MMMs). The...
Tasks that are too hard for single robot can be easily carried out by multiple robots in a cooperative manner. If some/all robots have mobile bases, the cooperation is subjected to great uncertainties in both the robotic system and environment. Therefore, the relationships among all the base frames (robot-robot calibration) and the relationships between the end-effectors and the other devices such...
Microphone arrays can be used for a number of applications such as speaker diarization and tracking. For these, it is necessary to calibrate their geometry with good precision. Manual measurement is cumbersome and impractical for ad hoc configurations as distributed sensor nodes. So an fast automated calibration method that provides sufficient accuracy is required. It is even more convenient if data...
The paper describes a 8.125–15.625 Gbps medium-reach SerDes macro for use in a networking memory system. The SerDes employs a sub-sampling ring-oscillator phase-locked loop to obtain a large frequency range with low jitter performance. In addition, the transmitter uses a modified hybrid output driver and a multi-step duty-cycle corrector. The receiver uses a BER-based calibration loop to find the...
Millimeter-wave holographic imaging system can acquire 3D images and is nonionzing, which especially fits human imaging. Widely utilized linear antenna arrays provide high scanning speed as well as non-uniformity artifacts. In this paper, we developed a set of calibration methods and image denoising algorithms to eliminate the influences of system errors including response non-uniformity, transmission...
A scaling-friendly, hybrid, two-stage ΔΣ ADC with a 5-bit SAR as first stage and a VCO as second stage is presented in this work. Since the VCO can provide fine quantization for small signals in the time-domain, it is used to directly quantize the SAR residue without OTA-based residue amplification. Also, having a small input swing obviates the need for VCO non-linearity calibration. The VCO phase...
This paper presents a digitally calibrated 12bit 12.5-MS/s successive-approximation-register (SAR) analog-to-digital converter (ADC) intended for low-power wireless communication and medical instrumentation. The performance of the proposed prototype is enhanced by two techniques. A power saving strategy is proposed. Also, several foreground calibration methods for SAR ADCs are proposed to reduce the...
▸ Today's high-speed I/O interfaces demand extensive modeling and simulation to: ▸ Design optimal equalization to compensate channel loss ▸ Compare different clocking schemes ▸ Verify functionalities of digital calibration/adaptation loops ▸ For effective system-level performance analysis, it is important to understand the key modeling requirements for each of the link components ▸ And to use an efficient...
Camera calibration constitutes a basic problem in many robot applications. In this paper two algorithms tailored to the calibration of the parameters of a depth camera are proposed. More precisely, a closed form solution that requires the coordinates of three corresponding points in the world and the camera coordinates systems, for the noise free case is proposed. Moreover, a robust algorithm that...
This paper studies the performance of the recently developed G-MUSIC algorithm as applied to the problem of brain source localization. G-MUSIC is a form of weighted MUSIC that performs better in scenarios where only limited sample support is available. Two transfer function based calibration algorithms are also developed to estimate the location of neural activity in the brain accurately when the...
Owing to their uttermost linearity, high-grade multimeters can be profitably used as voltage ratio standards. To exploit the high performances achievable, the residual nonlinearities must be evaluated with a quantum reference and particular attention is required to avoid reduction in accuracy. Differently from the resistive divider case, the ratio is obtained from actual voltage measurements, and...
An error vector magnitude (EVM) measurement method for W-CDMA source is proposed using a real time oscilloscope with traceability to SI unit. Also measurement uncertainty is evaluated based on a Monte-Carlo simulation, which takes into account the errors from the oscilloscope and signal processing. The measured EVM of a source at 900 MHz is 0.2535% ± 0.0057% at 95% confidence level.
Camera calibration is an important issue in computer vision. In this paper, we propose an improved camera auto-calibration algorithm from sequential images based on VP (vanishing point) and EKF (extended Kalman filter) to determine camera intrinsic parameters. This is the first vanishing point-based auto-calibration algorithm, which only uses a sequence of monocular images as input without any other...
This paper introduces a system to accurately measure conducted out-of-band (OOB) noise of IEEE 802.11b/g/a/n/ac transmitter signals in cellular frequencies with a spectrum analyzer. The low-level (<160dBm/Hz) OOB noise measurement is usually limited by the dynamic range and the thermal noise of a spectrum analyzer. The proposed setup notches out transmitter signals, amplifies OOB noise and uses...
Non-intrusive load meters (NILM) with load identification ability are developed in several institutes and companies. A system for calibration of such meters is presented in this paper. The system can simulate an arbitrary current waveform of a home appliance. A tested NILM measured the waveforms and a load identification probability was stated.
Historically, analog null meters have been used to determine zero voltage conditions in metrological applications. When digital multimeters (DMMs) became available with resolution comparable to null meters, they were adopted quickly, and analog null meters were set aside. Depending on the circuit and the DMM, significant measurement errors can be introduced. This paper discusses in detail investigations...
A cryogenic current comparator with an overall of 17,252 turns and windings including numbers of turns ranging from 20 to 213 has been realized. This system offers the possibility of resistance calibration at increased magnetic flux levels and allows for a direct calibration of 1 Ω to 100 MΩ normal resistors against the quantum Hall effect. Besides that, the very low-current measurements at PTB will...
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