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The Anatomy Of Programming Languages, Alice E. Fischer, Frances S. Grodzinsky Jan 1993

The Anatomy Of Programming Languages, Alice E. Fischer, Frances S. Grodzinsky

Electrical & Computer Engineering and Computer Science Book Series

The specific goals of this book are to help students learn: *To reason clearly about programming languages. *To develop principles of communication so that we can evaluate the wisdom and utility of the decisions made in the process of language design. *To break down language into its major components, and each component in to small pieces so that we can focus on competing alternatives. *To define a consistent and general set of terms for the components out of which programming languages are built, and the concepts on which they are based. * To use these terms to describe existing languages, …

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Measuring And Compensating For Transport Delay In Real-Time Interactive Driving Simulation, Joseph D. Dumas Ii Jan 1993

Measuring And Compensating For Transport Delay In Real-Time Interactive Driving Simulation, Joseph D. Dumas Ii

Retrospective Theses and Dissertations

Real-time, man-in-the-loop simulators are important tools for operator training as well as human performance research. Simulator implementation using digital computers offers many important advantages but may also cause problems. One of the most significant and troublesome artifacts of digital computer simulation is the presence of transport delays in the operator/vehicle control loop. Transport delays have been shown to destabilize the system, resulting in poorer control of the simulated vehicle. They may also contribute to an increased likelihood of simulator sickness in human operators. Therefore, it is desirable to be able to quantify simulator transport delays and to compensate the system …

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Direct Measurements Of The Transport Of Nonequilibrium Electrons In Gold Films With Different Crystal Structures, T. Juhasz, H. E. Elsayed-Ali, G. O. Smith, C. Suárez, W. E. Bron Jan 1993

Direct Measurements Of The Transport Of Nonequilibrium Electrons In Gold Films With Different Crystal Structures, T. Juhasz, H. E. Elsayed-Ali, G. O. Smith, C. Suárez, W. E. Bron

Electrical & Computer Engineering Faculty Publications

The transport of femtosecond-laser-excited nonequilibrium electrons across polycrystalline and single-crystalline gold films has been investigated through time-of-flight measurements. The thicknesses of the films range from 25 to 400 nm. Ballistic electrons as well as electrons interacting with other electrons and/or with the lattice have been observed. The ballistic component dominates the transport in the thinner films, whereas the interactive transport mechanism is dominant at the upper end of the thickness range. A slower effective velocity of the interactive component is observed in the polycrystalline samples, and is assumed to arise from the presence of grain boundaries. The reflection coefficient of …

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A Spectral Flux Method For Solving The Boltzmann Equation, Muhammad A. Alam, Mark A. Stettler, Mark S. Lundstrom Jan 1993

A Spectral Flux Method For Solving The Boltzmann Equation, Muhammad A. Alam, Mark A. Stettler, Mark S. Lundstrom

Department of Electrical and Computer Engineering Faculty Publications

A spectral method for solving the Boltzmann equation by the scattering matrix approach is presented, The algorithm discussed can be used to simulate both bulk and device properties with arbitrary field profiles. Although the primary goal is to reduce the data storage problem of the scattering matrix approach, many of the concepts and mathematical properties developed may be useful for other traditional spectral methods as well.

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Detection Of Skin Tumor Boundaries In Color Images, Fikret Erçal, M. Moganti, William V. Stoecker, Randy Hays Moss Jan 1993

Detection Of Skin Tumor Boundaries In Color Images, Fikret Erçal, M. Moganti, William V. Stoecker, Randy Hays Moss

Computer Science Faculty Research & Creative Works

A simple and yet effective method for finding the borders of tumors is presented as an initial step towards the diagnosis of skin tumors from their color images. The method makes use of an adaptive color metric from the red, green, and blue planes that contains information for discriminating the tumor from the background. Using this suitable coordinate transformation, the image is segmented. The tumor portion is then extracted from the segmented image and borders are drawn. Experimental results that verify the effectiveness of this approach are given

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Artificial Intelligence Applied To Detection Of Melanoma, Arve Kjoelen, Scott E. Umbaugh, William V. Stoecker, Randy Hays Moss Jan 1993

Artificial Intelligence Applied To Detection Of Melanoma, Arve Kjoelen, Scott E. Umbaugh, William V. Stoecker, Randy Hays Moss

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

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Faulty Behavior Of Storage Elements And Its Effects On Sequential Circuits, Waleed K. Al-Assadi, Y. K. Malaiya, A. P. Jayasumana Jan 1993

Faulty Behavior Of Storage Elements And Its Effects On Sequential Circuits, Waleed K. Al-Assadi, Y. K. Malaiya, A. P. Jayasumana

Electrical and Computer Engineering Faculty Research & Creative Works

It is often assumed that the faults in storage elements (SEs) can be modeled as output/input stuck-at faults of the element. They are implicitly considered equivalent to the stuck-at faults in the combinational logic surrounding the SE cells. Transistor-level faults in common SEs are examined here. A more accurate higher level fault model for elementary SEs that better represents the physical failures is presented. It is shown that a minimal (stuck-at) model may be adequate if only modest fault coverage is desired. The enhanced model includes some common fault behaviors of SEs that are not covered by the minimal fault …

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Automatic Color Segmentation Algorithms-With Application To Skin Tumor Feature Identification, Scott E. Umbaugh, Randy Hays Moss, William V. Stoecker, G. A. Hance Jan 1993

Automatic Color Segmentation Algorithms-With Application To Skin Tumor Feature Identification, Scott E. Umbaugh, Randy Hays Moss, William V. Stoecker, G. A. Hance

Electrical and Computer Engineering Faculty Research & Creative Works

Two color-image segmentation methods are described. The first is based on a spherical coordinate transform of original RGB data. The second is based on a mathematically optimal transform, the principal components transform (also known as eigenvector, discrete Karhunen-Loeve, or Hotelling transform). These algorithms are applied to the extraction from skin tumor images of various features such as tumor border, crust, hair scale, shiny areas, and ulcer. The results of this research will be used in the development of a computer vision system that will serve as the visual front-end of a medical expert system to automate visual feature identification for …

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Analog Chips And Intelligent Vehicles, J. G. Harris Jan 1993

Analog Chips And Intelligent Vehicles, J. G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

Numerous digital-based sensor systems have been demonstrated on intelligent vehicles but only the most rudimentary experiments have been attempted with analog VLSI chips in real-world environments. The most significant factor in the choice between analog and digital approaches to sensory processing in intelligent vehicles will be the cost of mass production. If analog sensors can be designed with enough speed, resolution and accuracy to solve sensory processing tasks, then the low-cost of mass production ensures that analog circuits will be the technology of choice for future generations of smart sensors. Current analog VLSI sensors do not have enough resolution and …

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Lightning Arrester Failure And Ferroresonance On A Distribution System, L. J. Bohmann, J. Mcdaniel, Eldon Keith Stanek Jan 1993

Lightning Arrester Failure And Ferroresonance On A Distribution System, L. J. Bohmann, J. Mcdaniel, Eldon Keith Stanek

Electrical and Computer Engineering Faculty Research & Creative Works

Since 1987 the Upper Peninsula Power Company (UPPCO) has been experiencing a large number of lightning arrester failures on a portion of their distribution system in southern Marquette County, Michigan. It was in the area of the Navy's Extremely Low Frequency (ELF) antenna where the distribution system had been recently reconfigured so that the transformers were connected line-to-line in order to eliminate interference from the antenna. A study was done which determined that the system was susceptible to ferro resonance during single line faults under lightly loaded conditions and that the overvoltage's experienced could be causing the lightning arrester failures. …

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Advanced Graphics Zoom In On Operations, Max Darwin Anderson, Hardy J. Pottinger, C. M. Schroeder Jan 1993

Advanced Graphics Zoom In On Operations, Max Darwin Anderson, Hardy J. Pottinger, C. M. Schroeder

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

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Battery Energy Storage Technologies, Max Darwin Anderson, Dodd S. Carr Jan 1993

Battery Energy Storage Technologies, Max Darwin Anderson, Dodd S. Carr

Electrical and Computer Engineering Faculty Research & Creative Works

Battery energy storage systems, comprising lead-acid batteries, power conversion systems, and control systems, are in commercial operation around the world. They are used by three main groups: power generating utilities; power distributing utilities; and major power consumers (such as electric furnace foundries). The principal advantages of battery energy storage systems to generating utilities include load leveling; frequency control; spinning reserve; modular construction; convenient siting; no emissions; and investment deferral for new generation and transmission equipment. Power distributing utilities and major power consumers can avoid costly demand changes by discharging their batteries at peak periods and then recharging with lower cost …

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Fuzzy Logic Applied To Adaptive Kalman Filtering, Marlys Rae Remus Dec 1992

Fuzzy Logic Applied To Adaptive Kalman Filtering, Marlys Rae Remus

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

The Kalman filter provides an effective means of estimating the state of a system from noisy measurements given that the system parameters are completely specified. The innovations sequence for a properly specified Kalman filter will be a zero-mean white noise process. However, when the system parameters change with time the Kalman filter will need to be adapted to compensate for the changes. Traditionally this has been accomplished by using nonlinear filtering, parallel Kalman filtering and covariance matching techniques. These methods have produced good results at the expense of large amounts of computational time. Necessary changes in the system parameters become …

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An Object-Oriented Computer Aided Design Program For Modern Control Systems Analysis, Frederick L. Trevino Dec 1992

An Object-Oriented Computer Aided Design Program For Modern Control Systems Analysis, Frederick L. Trevino

Theses and Dissertations

This investigation is a continuation of the ICECAP-PC research project conducted under Prof. Gary B. Lamont at the Air Force Institute of Technology. It is an ongoing development of a public domain Computer Aided Design (CAD) package for Control Engineering students and faculty, with a special emphasis on education. This investigation focuses on three areas. First, an object-oriented environment is specified, designed and implemented. The functional structure of ICECAP-PC is then converted into an object-oriented structure because object-orientation provides an advanced logic and implementation structure and effectively addresses common software engineering issues. Additionally, a new interface featuring pull-down menus, mouse …

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Optical Haar Wavelet Transforms Using Computer Generated Holography, Peter G. Block Dec 1992

Optical Haar Wavelet Transforms Using Computer Generated Holography, Peter G. Block

Theses and Dissertations

This research introduces an optical implementation of the continuous wavelet transform to filter images. The wavelet transform is modeled as a correlation process and is implemented with a Vander Lugt correlator. The orthonormal basis set used is composed of two one-dimensional Haar functions and a two-dimensional Haar function. Each wavelet, as well as its first two dyadic scalings, is implemented with computer generated holography. The Interferogram method, which represents a function only in terms of its phase, is used to encode the wavelet functions. The results are imaged onto a CCD array and captured using a framegrabber. The optical results …

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A Radiosity Approach To Realistic Image Synthesis, Richard L. Remington Dec 1992

A Radiosity Approach To Realistic Image Synthesis, Richard L. Remington

Theses and Dissertations

The Air Force Institute of Technology (AFIT) has not had the capability to generate photorealistic images. This thesis is a research effort to implement such a system at AFIT, and to apply knowledge from the particle transport community to this problem. Investigation into various techniques for generating photorealistic images led to the conclusion that the radiosity method would serve as the foundation for development. This is because of the increased accuracy of the diffuse reflections with the radiosity method and the fact that the images produced with radiosity axe view-independent. Two distinct tools to generate photorealistic images axe described. The …

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Etann Hardware Implementation For Radar Emitter Identification, James B. Calvin Jr. Dec 1992

Etann Hardware Implementation For Radar Emitter Identification, James B. Calvin Jr.

Theses and Dissertations

This study investigated classification of 30 radar emitters with 16 signal features using Intel's 80170NX chip, the Electronically Trainable Analog Neural Network (ETANN). Software tools were developed to characterize the ETANN sigmoidal transfer function for use in a custom simulator, known as Neural Graphics. Neural Graphics operates on a Silicon Graphics workstation. The Intel Neural Network Training System simulators were used in early experiments, but were found to be inefficient in training on data used in this research. Using a modified Neural Graphics simulator, single chip and multi-chip experiments were performed to provide benchmark results prior to performing chip-in-loop training. …

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A Generic Template Extractor (Gentex) In C For Vlsi Design Verification, Kenneth J. Mcclellan Jr. Dec 1992

A Generic Template Extractor (Gentex) In C For Vlsi Design Verification, Kenneth J. Mcclellan Jr.

Theses and Dissertations

The problem of VLSI design verification through circuit extraction was analyzed. The problems of creating a simple template format, the permutability of pins, maintaining connectivity, and performance were focused on. A generic template extractor (GENTEX) was developed in the C programming language for use as a testbed to find solutions to these problems. Six different extraction algorithms were tested with GENTEX and compared based on performance. EDIF translation programs were used to interface with GENTEX on both the input and output sides. One translation program converted an EDIF representation of a schematic into the template format used by GENTEX. The …

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Losses In Electric Power Systems, E. Benedict, T. Collins, D. Gotham, S. Hoffman, D. Karipides, S. Pekarek, R. Ramabhadran Dec 1992

Losses In Electric Power Systems, E. Benedict, T. Collins, D. Gotham, S. Hoffman, D. Karipides, S. Pekarek, R. Ramabhadran

Department of Electrical and Computer Engineering Technical Reports

This report concerns losses in power systems. The report was assembled by seven authors in EE 532 class at Purdue University in December, 1992. The work was part of a class project on losses . All aspects of losses are discussed from the transmission system through utilization stages. High efficiency motors and lighting are also considered . The students participating in this project also videotaped presentations on power system losses .

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Strategies For Optimal Control Design Of Normal Acceleration Command Following On The F-16, James C. Baird Dec 1992

Strategies For Optimal Control Design Of Normal Acceleration Command Following On The F-16, James C. Baird

Theses and Dissertations

Weight shapes and locations are investigated for H2, H∞, and the general mixed H2/H infinity optimization methodologies. The design model is normal acceleration command following for the F-16 (SISO) at Mach 0.6 and Sea Level, which yields a nonminimum phase and unstable plant. H2 design types include LQG, LQG/Sensitivity, and LQG/Tracking. Robustness and tracking are the objectives of the central H infinity process. Both H∞ optimal and suboptimal controllers are examined, with the suboptimal controller shown as the practical choice for this plant. The mixed H2/H∞ setup allows the tradeoff between …

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Design And Development Of A High-Speed Winograd Fast Fourier Transform Processor Board, James F. Herron Dec 1992

Design And Development Of A High-Speed Winograd Fast Fourier Transform Processor Board, James F. Herron

Theses and Dissertations

Since 1985, the Air Force Institute of Technology has pursued a project to develop a 4080-point Discrete Fourier Transform processor using the Winograd Fourier Transform Algorithm (WFTA) and Good-Thomas Prime Factoring Algorithm (PFA). In the first attempt to build a working system, this research effort designed and constructed, in part, a modified single processor architecture in order to demonstrate the proof of concept of the WFTA system design. This prototype architecture is simpler in implementation but uses the same principles and procedures as those of the 4080-point WFTA design. The design developed in this thesis was validated using the Very …

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Version And Transaction Management In Osmagic: An Object-Oriented Database Implementation Of The Magic Vlsi Layout Design Tool, Gary M. Lightner Dec 1992

Version And Transaction Management In Osmagic: An Object-Oriented Database Implementation Of The Magic Vlsi Layout Design Tool, Gary M. Lightner

Theses and Dissertations

The goal of this thesis was to study the feasibility of using an object-oriented database management system to provide the functionality and performance needed to support a complex computer-aided design tool. We do this by modifying OSMagic, a prototype system of the Magic very large scale integrated (VLSI) circuit design tool implemented on the ObjectStore object- oriented database management system. OSMagic was changed to support three different interfaces to ObjectStore and to work in a networking environment. We then designed and examined the use of version and transaction management models as a means of addressing the weaknesses of the prototype …

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Scientific Visualization Of Volumetric Radar Cross Section Data, Thomas G. Wojszynski Dec 1992

Scientific Visualization Of Volumetric Radar Cross Section Data, Thomas G. Wojszynski

Theses and Dissertations

For aircraft design and mission planning, designers, threat analysts, mission planners, and pilots require a Radar Cross Section (RCS) central tendency with its associated distribution about a specified aspect and its relation to a known threat, Historically, RCS data sets have been statically analyzed to evaluate a d profile. However, Scientific Visualization, the application of computer graphics techniques to produce pictures of complex physical phenomena. appears to be a more promising tool to interpret this data. This work describes data reduction techniques and a surface rendering algorithm to construct and display a complex polyhedron from adjacent contours of RCS data. …

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Design And Characterization Of Optically Pumped Vertical Cavity Surface Emitting Lasers, Richard J. Bagnell Dec 1992

Design And Characterization Of Optically Pumped Vertical Cavity Surface Emitting Lasers, Richard J. Bagnell

Theses and Dissertations

Vertical Cavity Surface Emitting Lasers (VCSELs) are a form of semiconductor laser which have their cavity oriented orthogonally to the plane of the wafer. The orientation necessitates short cavities, highly reflective mirrors and a relatively high gain/loss ratio. Even so, the resultant superior exit beam characteristics and the tight packing density of the finished lasers provide strong motivation for pursuing the growth of these structures. This thesis details the design of an optically pumped InGaAs multiple quantum well periodic gain structure VCSEL with a 950 nm lasing wavelength. These growths were to be a first attempt at VCSEL construction, so …

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Automated Control Of Aircraft In Formation Flight, Louis E. Buzogany Dec 1992

Automated Control Of Aircraft In Formation Flight, Louis E. Buzogany

Theses and Dissertations

In this study, an automated formation control system for an aircraft formation comprised of one lead and multiple wing aircraft is analyzed. Second- order models of the C-130 aircraft are developed in order to accurately model the flying qualities of large aircraft. This automated formation control system is capable of controlling the C-130 aircraft in maneuvering formation flight, thus reducing the wing's pilot workload. During formation flight, the wing aircraft continuously measures the lead aircraft's relative position with an ideal on-board position sensor. This information, in addition to Proportional Plus Integral feedback control, is used to maintain the aircraft in …

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Kalman Filter Tracking Of A Ballistic Missile Using Forward Looking Infrared Measurements And Doppler Returns, Michael L. Ching Dec 1992

Kalman Filter Tracking Of A Ballistic Missile Using Forward Looking Infrared Measurements And Doppler Returns, Michael L. Ching

Theses and Dissertations

The Air Force Institute of Technology (AFIT) has been involved in developing Kalman Filter trackers for airborne targets for the last 14 years. The goal of this particular thesis was to track a ballistic missile in the boost phase at ranges up to 2000 km, in order to control a high energy laser weapon designed to destroy the target The filter developed combined an existing 'FLIR' filter, which estimated location of the plume intensity centroid based on measurements from a forward looking infrared sensor (FLIR), and an existing center-of-mass filter, which estimated the offset between the plume and missile center-of-mass …

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Satcom General Purpose Modem Dscs Iii Sct Beacon Telemetry Display, James D. Coppola Dec 1992

Satcom General Purpose Modem Dscs Iii Sct Beacon Telemetry Display, James D. Coppola

Theses and Dissertations

This thesis documents the design and implementation of a DSCS III single Channel Transponder (SCT) beacon telemetry display. The system is a personal computer based design which interfaces to three SCT beacon receiver/demodulators. The software was designed to decode and display both the DSCS III A and DSCS HI B satellite beacons. Recordings of the SCT beacon display can be made on paper and/or magnetic media when triggered by the user, a watchdog timer, or the SCT command accept telemetry bit. In addition, the system can be configured with an IRIG B Universal Time Coordinates (UTC) card which enables the …

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High Range Resolution Radar Target Identification Using The Prony Model And Hidden Markov Models, Mark R. Dewitt Dec 1992

High Range Resolution Radar Target Identification Using The Prony Model And Hidden Markov Models, Mark R. Dewitt

Theses and Dissertations

Fully polarized Xpatch signatures are transformed to two left circularly polarized signals. These two signals are then filtered by a linear FM pulse compression ('chirp') transfer function, corrupted by AWGN, and filtered by a filter matched to the 'chirp' transfer function. The bandwidth of the 'chirp' radar is about 750 MHz. Range profile feature extraction is performed using the TLS Prony Model parameter estimation technique developed at Ohio State University. Using the Prony Model, each scattering center is described by a polarization ellipse, relative energy, frequency response, and range. This representation of the target is vector quantized using a K-means …

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Failure Identification Using Multiple Model Adaptive Estimation For The Lambda Flight Vehicle, Peter D. Hanlon Dec 1992

Failure Identification Using Multiple Model Adaptive Estimation For The Lambda Flight Vehicle, Peter D. Hanlon

Theses and Dissertations

This study develops and investigates the performance of a Multiple Model Adaptive Estimator (MMAE) to detect and identify control surface and sensor failures on the LAMBDA flight vehicle (a URV developed by Wright Laboratories). The MMAE uses a bank of Kalman filters that predict the aircraft response to a given input, with each filter model based on a different failure hypothesis, and then forms the residual difference between the prediction and sensor measurements for each filter. The MMAE uses these residuals to determine the probabilities of the failures that are modeled by the Kalman filters. Initially the MMAE identified all …

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Remote Sensing Of Turbulence And Transverse Atmospheric Wind Profiles Using Optical Reference Sources, Steven C. Koeffler Dec 1992

Remote Sensing Of Turbulence And Transverse Atmospheric Wind Profiles Using Optical Reference Sources, Steven C. Koeffler

Theses and Dissertations

This thesis examines a remote sensing technique for measuring the atmospheric structure constant and the transverse atmospheric wind velocity as a function of altitude by performing temporal and spatial correlations of band pass filtered wave front slope sensor measurements. Two point sources are used to illuminate two pairs-of cc>-located wave front slope sensors. The sources and sensors are arranged to give rise to crossed optical paths. For each pair of wave front slope sensors, the output of the larger sensor is subtracted from the output of the smaller sensor. This band pass filters the smaller sensor's output. The filtered …

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