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1

Optimization of membership function parameters for fuzzy controllers of an autonomous mobile robot using the flower pollination algorithm

Carvajal O. R., Castillo O., Soria J.

Journal of Automation Mobile Robotics and Intelligent Systems

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2018

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Vol. 12, No. 1

44--49

EN

In this work we describe the optimization of a Fuzzy Logic Controller (FLC) for an autonomous mobile robot that needs to follow a desired path. The FLC is for the simulation of its trajectory, the parameters of the membership functions of the FLC had not been previously optimized. We consider in this work with the flower pollination algorithm (FPA) as a method for optimizing the FLC. For this reason, we use the FPA to find the best parameters with the objective of minimizing the error between the trajectory of the robot and the reference. A comparative study of results with different metaheuristics is also presented in this work.

2

Ensembling a linear regression model with an error mitigation component

Nowosielski A., Kowalski P. A., Kulczycki P.

Journal of Automation Mobile Robotics and Intelligent Systems

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2018

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Vol. 12, No. 1

40--43

EN

This paper presents a proposal of a model error mitigation technique based on the error distribution analysis of the original model and creatng the additional model that tempers the error impact in particular domain areas identified as the most sensitive. both models are then combined into single ensemble model. The idea is demonstrated on the trivial two-dimensional linear regression model.

3

Microthermomechanical infrared sensors

Steffanson M., Rangelow I. W.

Opto-Electronics Review

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2014

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Vol. 22, No. 1

1-15

EN

We present a state-of-the-art overview of microthermomechanical infrared sensor technology. The working principle of this sensor is based on a bi-material actuated micromechanical deflection, generated by an induced temperature rise due to incident infrared radiation absorption. In order to generate a thermal image the thermomechanical deflections of the freestanding microstructures are read by either capacitive, piezoresistive or optical means. Research and development activities in this field began in the early 1990s. The development of this technology within the last 20 years has resulted in innovations such as uncooled multiband infrared detection, high-speed infrared sensing and uncooled THz imaging. This paper outlines representative milestones of this technology and analyses important results of notable groups. Significant activities on capacitive and optical readout techniques of thermomechanical infrared arrays are presented. Furthermore the advantages of microthermomechanical infrared sensors over current well-established uncooled infrared technologies are summarized. In conclusion the latest developments of this technology offer a highly potential solution for a variety of important energy-saving, safety and security applications.

4

320x256 HgCdTe IR FPA with a built-in shortwave cut-off filter

Vasilyev V. V., Varavin V. S., Dvoretsky S. A., Marchishin I. V., Mikhailov N. N., Predein A. V., Remesnik V. G., Sabinina I. V., Sidorov Y. G., Susliakov O. A.

Opto-Electronics Review

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2010

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Vol. 18, No. 3

236-240

EN

A photovoltaic detector design based on the graded band gap HgCdTe MBE structure with high conductivity layer (HCL) at interface, which provides photodiodes series resistance and a shortwave cut.off filter is developed. The optimal HCL parameters giving high quantum efficiency and minimal noise equivalent temperature difference were determined by calculations and experimentally confirmed. The hybrid 320x256 IR FPA operating in 8-12 μm spectral range was fabricated. The threshold power responsivity and minimal noise equivalent temperature difference values at wavelength maximum were 1.02x10⁻⁷ W/cm², 4.1x10⁸ V/W and 27 mK, respectively.

5

Noise minimization via deep submicron system-on-chip integration in megapixel CMOS imaging sensors

Kozlowski L. J.

Opto-Electronics Review

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2006

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Vol. 14, No. 1

11-18

EN

Infrared sensor designers have long maximized S/N ratio by employing pixel-based amplification in conjunction with supplemental noise suppression. Instead, we suppress photodiode noise using novel SoC implementation with simple three transistor pixel; supporting SoC components include a feedback amplifier having elements distributed amongst the pixel and column buffer, a tapered reset clock waveform, and reset timing generator. The tapered reset method does not swell pixel area, compel processing of the correlated reset and signal values, or require additional memory. Integrated in a 2.1 M pixel imager developed for generating high definition television, random noise is ~8e- at video rates to 225 MHz. Random noise of ~30e would otherwise be predicted for the 5 µm by 5 µm pixels having 5.5 fF detector capacitance with negligible image lag. Minimum sensor S/N ratio is 52 dB with 1920 by 1080 progressive readout at 60 Hz, 72 Hz and 90 Hz. Fixed pattern noise is <2 DN via on-chip signal processing.

6

Numerical simulations for HgCdTe related detectors

Yoo S. D., Jo N. H., Ko B. G., Chang J., Park J. G., Kwack K. D.

Opto-Electronics Review

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1999

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Vol. 7, No. 4

347-356

EN

In this paper we introduce a new HgCdTe 2-dimensional numerical simulator, HanYang University Semiconductor Device Simulator (HYSEDES). HYSEDES adopts the modifield transport models to describe the inherent natures of HgCdTe such as the degeneracy, the nonparabolic conduction band, and the band offset at heterointerface. It also takes into account various generation - recombination mechanisms regarding tunnelling phenomena and optical generation. For the advanced devices employing multiple junctions, all the material parameters are described as a function of the position. The simulation results are reported for photovoltaic devices and focal plane array. We also proposed a structure to improve the characteristics in focal plane array, i. e., to reduce crosstalk with slight degrading quantum efficiency.

7

Low-noise infrared and visible focal plane arrays

Kozlowski L., Vural K., Luo J., Tomasini A., Liu T., Kleinhans W.E.

Opto-Electronics Review

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1999

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Vol. 7, No. 4

259-269

EN

While charge-coupled device ( CCD ) technology is often perceived to provide nearly optimum signal multiplexing and very low imager noise, coupling high performance detectors ( at cutoff wavelengths from 0.6 žmto 17 um ) to CMOS multiplexers provides lower (<10 e-) read noise at high data rates using several pixel amplifier schemes. This superiority is fundamental and has been validated on infrared and visible focal plane arrays. Thus the robust pixel-based signal amplification facilitated by sub-micron CMOS is stimulating low-noise focal plane array (FPA) development for discriminating applications including infrared astronomy, wavefront sensing, spectroscopy, and spaceborne images. Enabled by Moore's Law and concomitant increases in integration density, commercial imagers for consumer video are also providing very low read noise and high sensitivity. Hence we report the ability to usefully detect quanta at non-cryogenic operating temperatures because read noise is at the single-electron level at high video rates. While such advances are typically first demonstrated on infrared sensors, the enhancements migrate to visible devices as soon as the available lithography of the prevailing silicon CMOS technology permits, because visible imager pixels are necessarily much smaller to match the optical blur.