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• 1. [Article] Parallel approximate string matching applied to occluded object recognition

  This thesis develops an algorithm for approximate string matching and applies it to the problem of partially occluded object recognition. The algorithm measures the similarity of differing strings by scanning ...

  Citation × Citation Citation Abstract Copy Title: Parallel approximate string matching applied to occluded object recognition Author: Smith, David Year: 1987 This thesis develops an algorithm for approximate string matching and applies it to the problem of partially occluded object recognition. The algorithm measures the similarity of differing strings by scanning for matching substrings between strings. The length and number of matching substrings determines the amount of similarity. A classification algorithm is developed using the approximate string matching algorithm for the identification and classification of objects. A previously developed method of shape description is used for object representation. Title: Parallel approximate string matching applied to occluded object recognition Author: Smith, David Year: 1987 This thesis develops an algorithm for approximate string matching and applies it to the problem of partially occluded object recognition. The algorithm measures the similarity of differing strings by scanning for matching substrings between strings. The length and number of matching substrings determines the amount of similarity. A classification algorithm is developed using the approximate string matching algorithm for the identification and classification of objects. A previously developed method of shape description is used for object representation. Close

• 2. [Article] What We Know After Twelve Years Developing and Deploying Test Data Analytics Solutions

  Since 2004, Texas Instruments and Portland State University have collaborated to develop and deploy test data analytical methods for use in a variety of applications, including quality screening, burn-in ...

  Citation × Citation Citation Abstract Copy Title: What We Know After Twelve Years Developing and Deploying Test Data Analytics Solutions Author: Butler, Kenneth M., Nahar, Amit, Daasch, W. Robert Year: 2017 Since 2004, Texas Instruments and Portland State University have collaborated to develop and deploy test data analytical methods for use in a variety of applications, including quality screening, burn-in minimization, high cost test replacement and/or removal, and operations monitoring. In this paper, key findings amassed during this time are summarized. Title: What We Know After Twelve Years Developing and Deploying Test Data Analytics Solutions Author: Butler, Kenneth M., Nahar, Amit, Daasch, W. Robert Year: 2017 Since 2004, Texas Instruments and Portland State University have collaborated to develop and deploy test data analytical methods for use in a variety of applications, including quality screening, burn-in minimization, high cost test replacement and/or removal, and operations monitoring. In this paper, key findings amassed during this time are summarized. Close

• 3. [Article] Counterintuitive Results in Underwater Acoustic Communications

  Book chapter. Underwater wireless communication using acoustic signals is a difficult problem and progress in finding robust solutions has been disappointing. Methods employed successfully in terrestrial ...

  Citation × Citation Citation Abstract Copy Title: Counterintuitive Results in Underwater Acoustic Communications Author: Rouseff, Daniel Year: 2016 Book chapter. Underwater wireless communication using acoustic signals is a difficult problem and progress in finding robust solutions has been disappointing. Methods employed successfully in terrestrial wireless communications have not always transitioned successfully to underwater scenarios. An engineer’s intuition developed in solving the terrestrial problem may actually become a hindrance to solving the underwater problem. In the present work, several seemingly counterintuitive experimental results are examined: communications performance can be better when the range is longer rather than shorter, when the sea surface is rough rather than calm, when the bathymetry is undulating rather than flat. Physics-based explanations for the observed results are developed. A physicist’s intuition, however, also may fail when trying to develop useful models. A seemingly counterintuitive fact is that acoustic paths that undergo incoherent reflection from a rough sea surface can be shown experimentally to be useful for coherent communications. The requirements for a proper physics-based model are sketched. Title: Counterintuitive Results in Underwater Acoustic Communications Author: Rouseff, Daniel Year: 2016 Book chapter. Underwater wireless communication using acoustic signals is a difficult problem and progress in finding robust solutions has been disappointing. Methods employed successfully in terrestrial wireless communications have not always transitioned successfully to underwater scenarios. An engineer’s intuition developed in solving the terrestrial problem may actually become a hindrance to solving the underwater problem. In the present work, several seemingly counterintuitive experimental results are examined: communications performance can be better when the range is longer rather than shorter, when the sea surface is rough rather than calm, when the bathymetry is undulating rather than flat. Physics-based explanations for the observed results are developed. A physicist’s intuition, however, also may fail when trying to develop useful models. A seemingly counterintuitive fact is that acoustic paths that undergo incoherent reflection from a rough sea surface can be shown experimentally to be useful for coherent communications. The requirements for a proper physics-based model are sketched. Close

• 4. [Article] Consistency in Wafer Based Outlier Screening

  Outlier screening is a popular approach for testing automotive products. In practice, developing an outlier model can be subjective, making justification of the model challenging. In this paper we propose ...

  Citation × Citation Citation Abstract Copy Title: Consistency in Wafer Based Outlier Screening Author: Siatkowski, Sebastian, Shan, Chuanhe Jay, Wang, Li-C., Sumikawat, Nikolas, Daasch, W. Rober, Carulli, John M. Year: 2016 Outlier screening is a popular approach for testing automotive products. In practice, developing an outlier model can be subjective, making justification of the model challenging. In this paper we propose a new concept called Consistency which provides a data-driven objective way to assess an outlier model. We study the development of outlier models in view of this new model consistency concept and report experimental findings on an automotive product line. Title: Consistency in Wafer Based Outlier Screening Author: Siatkowski, Sebastian, Shan, Chuanhe Jay, Wang, Li-C., Sumikawat, Nikolas, Daasch, W. Rober, Carulli, John M. Year: 2016 Outlier screening is a popular approach for testing automotive products. In practice, developing an outlier model can be subjective, making justification of the model challenging. In this paper we propose a new concept called Consistency which provides a data-driven objective way to assess an outlier model. We study the development of outlier models in view of this new model consistency concept and report experimental findings on an automotive product line. Close

• 5. [Article] Biology Goes Digital: An array of 5,700 Spartan FPGAs brings the BioWall to "life"

  A unique, scientific research instrument and art piece, the BioWall models bio-inspired electronic tissues capable of evolution, selfrepair, self-replication – and learning. Much pure and applied scientific ...

  Citation × Citation Citation Abstract Copy Title: Biology Goes Digital: An array of 5,700 Spartan FPGAs brings the BioWall to "life" Author: Teuscher, Christof, Tempesti, Gianluca Year: 2003 A unique, scientific research instrument and art piece, the BioWall models bio-inspired electronic tissues capable of evolution, selfrepair, self-replication – and learning. Much pure and applied scientific research has focused on replicating biological functions in digital hardware. Here, at the Logic Systems Laboratory of the Swiss Federal Institute of Technology in Lausanne (EPFL), we have utilized 5,700 Xilinx Spartan™ FPGAs, in multiple configurations, to build bio-inspired computing machines that exploit three essential biological models: • Phylogenesis – the history of the evolution of the species • Ontogenesis – the development of an individual as directed by his genetic code • Epigenesis – the development of an individual through learning processes (nervous system, immune system), influenced both by genetic code (the innate) and environment (the acquired). Although we have individually and jointly investigated all three models, we have concentrated on the ontogenetic model through the Embryonics (embryonic electronics) Project. This project studies the development of multi-cellular organisms for the purpose of obtaining in digital hardware some of the features of biological organisms, notably growth and fault tolerance. Title: Biology Goes Digital: An array of 5,700 Spartan FPGAs brings the BioWall to "life" Author: Teuscher, Christof, Tempesti, Gianluca Year: 2003 A unique, scientific research instrument and art piece, the BioWall models bio-inspired electronic tissues capable of evolution, selfrepair, self-replication – and learning. Much pure and applied scientific research has focused on replicating biological functions in digital hardware. Here, at the Logic Systems Laboratory of the Swiss Federal Institute of Technology in Lausanne (EPFL), we have utilized 5,700 Xilinx Spartan™ FPGAs, in multiple configurations, to build bio-inspired computing machines that exploit three essential biological models: • Phylogenesis – the history of the evolution of the species • Ontogenesis – the development of an individual as directed by his genetic code • Epigenesis – the development of an individual through learning processes (nervous system, immune system), influenced both by genetic code (the innate) and environment (the acquired). Although we have individually and jointly investigated all three models, we have concentrated on the ontogenetic model through the Embryonics (embryonic electronics) Project. This project studies the development of multi-cellular organisms for the purpose of obtaining in digital hardware some of the features of biological organisms, notably growth and fault tolerance. Close

• 6. [Article] Microwave Instrumentation and Sensing Techniques for Quantum Efficiency and Minority-Carrier Lifetime Measurements

  A non-contact method characterizing the quantum efficiency of a solar cell using the microwave reflectance signature is presented in this thesis. Traditional solar cell quantum efficiency (QE) measurements ...

  Citation × Citation Citation Abstract Copy Title: Microwave Instrumentation and Sensing Techniques for Quantum Efficiency and Minority-Carrier Lifetime Measurements Author: Lu, Kyle Benjamin Year: 2017 A non-contact method characterizing the quantum efficiency of a solar cell using the microwave reflectance signature is presented in this thesis. Traditional solar cell quantum efficiency (QE) measurements are only possible near the completion of the fabrication process using contacts in direct physical connection with the metalized surface tabs to probe and extract charge carriers from the device. However, pressure within the solar metrology industry to report the spectral performance of the device earlier in the manufacturing process as part of the process control loop requires that a new non-contact method be developed. This thesis work contributes the development of a non-contact focused microwave reflectance technique capable of acquiring the full 365nm - 1100nm spectrum in under 1 minute. Unlike many similar Time Resolved Microwave Conductivity (TRMC) and Microwave Photoconductivity Decay (µPCD) systems based on the open-ended waveguide technique, this measurement is developed to perform measurements in the far-field. As such, a different mechanism for understanding the problem is presented using the modulated scatterer concept from antenna theory. Using a combination of high dielectric sensor pads and negative-index of refraction microwave lenses, we are able to tune the far-field field probe size from 5mm-150mm allowing for high speed single point in-line measurements or high spatial sensitivity laboratory measurements. Title: Microwave Instrumentation and Sensing Techniques for Quantum Efficiency and Minority-Carrier Lifetime Measurements Author: Lu, Kyle Benjamin Year: 2017 A non-contact method characterizing the quantum efficiency of a solar cell using the microwave reflectance signature is presented in this thesis. Traditional solar cell quantum efficiency (QE) measurements are only possible near the completion of the fabrication process using contacts in direct physical connection with the metalized surface tabs to probe and extract charge carriers from the device. However, pressure within the solar metrology industry to report the spectral performance of the device earlier in the manufacturing process as part of the process control loop requires that a new non-contact method be developed. This thesis work contributes the development of a non-contact focused microwave reflectance technique capable of acquiring the full 365nm - 1100nm spectrum in under 1 minute. Unlike many similar Time Resolved Microwave Conductivity (TRMC) and Microwave Photoconductivity Decay (µPCD) systems based on the open-ended waveguide technique, this measurement is developed to perform measurements in the far-field. As such, a different mechanism for understanding the problem is presented using the modulated scatterer concept from antenna theory. Using a combination of high dielectric sensor pads and negative-index of refraction microwave lenses, we are able to tune the far-field field probe size from 5mm-150mm allowing for high speed single point in-line measurements or high spatial sensitivity laboratory measurements. Close

• 7. [Article] Two new parallel processors for real time classification of 3-D moving objects and quad tree generation

  Two related image processing problems are addressed in this thesis. First, the problem of identification of 3-D objects in real time is explored. An algorithm to solve this problem and a hardware system ...

  Citation × Citation Citation Abstract Copy Title: Two new parallel processors for real time classification of 3-D moving objects and quad tree generation Author: Majd, Farjam Year: 1985 Two related image processing problems are addressed in this thesis. First, the problem of identification of 3-D objects in real time is explored. An algorithm to solve this problem and a hardware system for parallel implementation of this algorithm are proposed. The classification scheme is based on the "Invariant Numerical Shape Modeling" (INSM) algorithm originally developed for 2-D pattern recognition such as alphanumeric characters. This algorithm is then extended to 3-D and is used for general 3-D object identification. The hardware system is an SIMD parallel processor, designed in bit slice fashion for expandability. It consists of a library of images coded according to the 3-D INSM algorithm and the SIMD classifier which compares the code of the unknown image to the library codes in a single clock pulse to establish its identity. The output of this system consists of three signals: U, for unique identification; M, for multiple identification; and N, for non-identification of the object. Second, the problem of real time image compaction is addressed. The quad tree data structure is described. Based on this structure, a parallel processor with a tree architecture is developed which is independent of the data entry process, i.e., data may be entered pixel by pixel or all at once. The hardware consists of a tree processor containing a tree generator and three separate memory arrays, a data transfer processor, and a main memory unit. The tree generator generates the quad tree of the input image in tabular form, using the memory arrays in the tree processor for storage of the table. This table can hold one picture frame at a given time. Hence, for processing multiple picture frames the data transfer processor is used to transfer their respective quad trees from the tree processor memory to the main memory. An algorithm is developed to facilitate the determination of the connections in the circuit. Title: Two new parallel processors for real time classification of 3-D moving objects and quad tree generation Author: Majd, Farjam Year: 1985 Two related image processing problems are addressed in this thesis. First, the problem of identification of 3-D objects in real time is explored. An algorithm to solve this problem and a hardware system for parallel implementation of this algorithm are proposed. The classification scheme is based on the "Invariant Numerical Shape Modeling" (INSM) algorithm originally developed for 2-D pattern recognition such as alphanumeric characters. This algorithm is then extended to 3-D and is used for general 3-D object identification. The hardware system is an SIMD parallel processor, designed in bit slice fashion for expandability. It consists of a library of images coded according to the 3-D INSM algorithm and the SIMD classifier which compares the code of the unknown image to the library codes in a single clock pulse to establish its identity. The output of this system consists of three signals: U, for unique identification; M, for multiple identification; and N, for non-identification of the object. Second, the problem of real time image compaction is addressed. The quad tree data structure is described. Based on this structure, a parallel processor with a tree architecture is developed which is independent of the data entry process, i.e., data may be entered pixel by pixel or all at once. The hardware consists of a tree processor containing a tree generator and three separate memory arrays, a data transfer processor, and a main memory unit. The tree generator generates the quad tree of the input image in tabular form, using the memory arrays in the tree processor for storage of the table. This table can hold one picture frame at a given time. Hence, for processing multiple picture frames the data transfer processor is used to transfer their respective quad trees from the tree processor memory to the main memory. An algorithm is developed to facilitate the determination of the connections in the circuit. Close

• 8. [Article] The Investigation and Optimization of a Two-Heat-Pump System Incorporating Thermal Storage for Shaping Residential Heating Load

  Portland General Electric has proposed coupling one or more water tanks with two heat pumps in order to perform load-shifting in residential customer heating and cooling applications. By using the water ...

  Citation × Citation Citation Abstract Copy Title: The Investigation and Optimization of a Two-Heat-Pump System Incorporating Thermal Storage for Shaping Residential Heating Load Author: Barrett, Emily Lord Year: 2016 Portland General Electric has proposed coupling one or more water tanks with two heat pumps in order to perform load-shifting in residential customer heating and cooling applications. By using the water tanks as a thermal storage unit, this project attempts to partially decouple energy consumption from generation to provide peak demand reduction and to better facilitate the integration of variable renewable energy resources. A scoping study was performed to evaluate the potential impact of this project if implemented in single family homes in Portland, Oregon. This study revealed that the system could provide meaningful savings in the cost of electricity to both the customer and utility. Additionally, an optimization algorithm was developed to dictate system operation and to maximize gains to the utility. Evolutionary algorithms were explored in an attempt to increase the effectiveness of the algorithm's search in limited computation time. Ultimately, an evolution strategy was selected as the most suitable based on tests run in winter and spring months. A genetic algorithm was then developed to handle fixed-speed heat pump operation for compatibility with an alpha-system prototype that has been developed by the research team. Title: The Investigation and Optimization of a Two-Heat-Pump System Incorporating Thermal Storage for Shaping Residential Heating Load Author: Barrett, Emily Lord Year: 2016 Portland General Electric has proposed coupling one or more water tanks with two heat pumps in order to perform load-shifting in residential customer heating and cooling applications. By using the water tanks as a thermal storage unit, this project attempts to partially decouple energy consumption from generation to provide peak demand reduction and to better facilitate the integration of variable renewable energy resources. A scoping study was performed to evaluate the potential impact of this project if implemented in single family homes in Portland, Oregon. This study revealed that the system could provide meaningful savings in the cost of electricity to both the customer and utility. Additionally, an optimization algorithm was developed to dictate system operation and to maximize gains to the utility. Evolutionary algorithms were explored in an attempt to increase the effectiveness of the algorithm's search in limited computation time. Ultimately, an evolution strategy was selected as the most suitable based on tests run in winter and spring months. A genetic algorithm was then developed to handle fixed-speed heat pump operation for compatibility with an alpha-system prototype that has been developed by the research team. Close

• 9. [Article] Distributed Solar Photovoltaic Grid Integration System : A Case Study for Performance

  The needs to the sustainable development of electricity, energy efficiency improvement, and environment pollution reduction have favored the development of distributed generation (DG). But the problems ...

  Citation × Citation Citation Abstract Copy Title: Distributed Solar Photovoltaic Grid Integration System : A Case Study for Performance Author: Shen, Ming Year: 2012 The needs to the sustainable development of electricity, energy efficiency improvement, and environment pollution reduction have favored the development of distributed generation (DG). But the problems come with increasing DG penetration in distribution networks. This thesis presents the Solar Energy Grid Integration System (SEGIS) Stage III project done by Portland General Electric (PGE), Advanced Energy, Sandia National Lab on a PGE selected distribution feeder. The feeder has six monitored commercial solar PV systems connected. The total power output from the PV systems has the potential to reach 30% of the feeder load. The author analyzes the performance of the solar feeder on both generation and voltage effects. As a project report, it introduced a new islanding detection done by other team members to give an islanding solution of future high penetration distribution networks. At last, the author describes micro-grid and grid support concepts in a SEGIS concept paper with some examples. Title: Distributed Solar Photovoltaic Grid Integration System : A Case Study for Performance Author: Shen, Ming Year: 2012 The needs to the sustainable development of electricity, energy efficiency improvement, and environment pollution reduction have favored the development of distributed generation (DG). But the problems come with increasing DG penetration in distribution networks. This thesis presents the Solar Energy Grid Integration System (SEGIS) Stage III project done by Portland General Electric (PGE), Advanced Energy, Sandia National Lab on a PGE selected distribution feeder. The feeder has six monitored commercial solar PV systems connected. The total power output from the PV systems has the potential to reach 30% of the feeder load. The author analyzes the performance of the solar feeder on both generation and voltage effects. As a project report, it introduced a new islanding detection done by other team members to give an islanding solution of future high penetration distribution networks. At last, the author describes micro-grid and grid support concepts in a SEGIS concept paper with some examples. Close

• 10. [Article] Automatic Fix for C Integer Errors by Precision Improvement

  Integer errors in C program may lead to serious failures and vulnerabilities. They are harbored in a wide range of programs including mature software such as Linux kernel. Code reviewing is laborious and ...

  Citation × Citation Citation Abstract Copy Title: Automatic Fix for C Integer Errors by Precision Improvement Author: Cheng, Xi, Zhou, Min, Song, Xiaoyu, Gu, Ming, Sun, Jiaguang Year: 2016 Integer errors in C program may lead to serious failures and vulnerabilities. They are harbored in a wide range of programs including mature software such as Linux kernel. Code reviewing is laborious and cannot guarantee reliable fixes for errors. Addressing potential errors in the development phase is error-prone even for experts and essentially hinders developing efficiency. In this paper we propose a novel approach to automate fix for C integer errors. Our approach directly replaces original C integers with dynamic-precision integers to fix potential errors without detecting them in advance. Many errors can be fixed by precision improvement without changing the design of application. We implement a tool CIntFix to automatically fix C integer errors. CIntFix succeeds in fixing all 5414 programs in NIST's Juliet test suite from 7 weakness categories. Meanwhile, on Juliet test suite and SPEC CINT2000 benchmarks, CIntFix processes C source code at the rate of 0.157s/KLOC and the fixed programs have 18.0% slowdown on average. The results show that CIntFix is capable to fix integer errors in real-world C programs. Title: Automatic Fix for C Integer Errors by Precision Improvement Author: Cheng, Xi, Zhou, Min, Song, Xiaoyu, Gu, Ming, Sun, Jiaguang Year: 2016 Integer errors in C program may lead to serious failures and vulnerabilities. They are harbored in a wide range of programs including mature software such as Linux kernel. Code reviewing is laborious and cannot guarantee reliable fixes for errors. Addressing potential errors in the development phase is error-prone even for experts and essentially hinders developing efficiency. In this paper we propose a novel approach to automate fix for C integer errors. Our approach directly replaces original C integers with dynamic-precision integers to fix potential errors without detecting them in advance. Many errors can be fixed by precision improvement without changing the design of application. We implement a tool CIntFix to automatically fix C integer errors. CIntFix succeeds in fixing all 5414 programs in NIST's Juliet test suite from 7 weakness categories. Meanwhile, on Juliet test suite and SPEC CINT2000 benchmarks, CIntFix processes C source code at the rate of 0.157s/KLOC and the fixed programs have 18.0% slowdown on average. The results show that CIntFix is capable to fix integer errors in real-world C programs. Close