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Mining Diversified Decision Trees Across Multiple Datasets To Capture Similarities And Alignable Differences, Qian Han 2013 Wright State University

Mining Diversified Decision Trees Across Multiple Datasets To Capture Similarities And Alignable Differences, Qian Han

Browse all Theses and Dissertations

This dissertation studies the problem of mining shared and alignable difference knowledge structures across multiple datasets/applications. Shared and alignable difference knowledge structures are important for identifying analogies between application domains and for forming new hypothesis in challenging research applications, and for assessing the degree and types of knowledge-level similarities and differences between application domains for use in learning transfer. Generally speaking, shared knowledge structures characterize underlying datasets and highlight conceptual-level structural similarities among the datasets. This dissertation studies the mining of shared decision trees, which are a special type of shared knowledge structures. We first consider building one shared decision …


Optimal Network Topologies And Resource Mappings For Heterogeneous Networks-On-Chip, Haera Chung 2013 Portland State University

Optimal Network Topologies And Resource Mappings For Heterogeneous Networks-On-Chip, Haera Chung

Dissertations and Theses

Communication has become a bottleneck for modern microprocessors and multi-core chips because metal wires don't scale. The problem becomes worse as the number of components increases and chips become bigger. Traditional Systems-on-Chips (SoCs) interconnect architectures are based on shared-bus communication, which can carry only one communication transaction at a time. This limits the communication bandwidth and scalability. Networks-on-Chip (NoC) were proposed as a promising solution for designing large and complex SoCs. The NoC paradigm provides better scalability and reusability for future SoCs, however, long-distance multi-hop communication through traditional metal wires suffers from both high latency and power consumption. A radical …


Fpga-Based Implementation Of Dual-Frequency Pattern Scheme For 3-D Shape Measurement, Brent Bondehagen 2013 University of Kentucky

Fpga-Based Implementation Of Dual-Frequency Pattern Scheme For 3-D Shape Measurement, Brent Bondehagen

Theses and Dissertations--Electrical and Computer Engineering

Structured Light Illumination (SLI) is the process where spatially varied patterns are projected onto a 3-D surface and based on the distortion by the surface topology, phase information can be calculated and a 3D model constructed. Phase Measuring Profilometry (PMP) is a particular type of SLI that requires three or more patterns temporarily multiplexed. High speed PMP attempts to scan moving objects whose motion is small so as to have little impact on the 3-D model. Given that practically all machine vision cameras and high speed cameras employ a Field Programmable Gate Array (FPGA) interface directly to the image sensors, …


A Comprehensive Hdl Model Of A Line Associative Register Based Architecture, Matthew A. Sparks 2013 University of Kentucky

A Comprehensive Hdl Model Of A Line Associative Register Based Architecture, Matthew A. Sparks

Theses and Dissertations--Electrical and Computer Engineering

Modern processor architectures suffer from an ever increasing gap between processor and memory performance. The current memory-register model attempts to hide this gap by a system of cache memory. Line Associative Registers(LARs) are proposed as a new system to avoid the memory gap by pre-fetching and associative updating of both instructions and data. This thesis presents a fully LAR-based architecture, targeting a previously developed instruction set architecture. This architecture features an execution pipeline supporting SWAR operations, and a memory system supporting the associative behavior of LARs and lazy writeback to memory.


Power-Efficient And Low-Latency Memory Access For Cmp Systems With Heterogeneous Scratchpad On-Chip Memory, Zhi Chen 2013 University of Kentucky

Power-Efficient And Low-Latency Memory Access For Cmp Systems With Heterogeneous Scratchpad On-Chip Memory, Zhi Chen

Theses and Dissertations--Electrical and Computer Engineering

The gradually widening speed disparity of between CPU and memory has become an overwhelming bottleneck for the development of Chip Multiprocessor (CMP) systems. In addition, increasing penalties caused by frequent on-chip memory accesses have raised critical challenges in delivering high memory access performance with tight power and latency budgets. To overcome the daunting memory wall and energy wall issues, this thesis focuses on proposing a new heterogeneous scratchpad memory architecture which is configured from SRAM, MRAM, and Z-RAM. Based on this architecture, we propose two algorithms, a dynamic programming and a genetic algorithm, to perform data allocation to different memory …


Human Performance Regression Testing, Amanda Swearngin, Myra B. Cohen, Bonnie E. John, Rachel K. E. Bellamy 2013 University of Nebraska-Lincoln

Human Performance Regression Testing, Amanda Swearngin, Myra B. Cohen, Bonnie E. John, Rachel K. E. Bellamy

School of Computing: Conference and Workshop Papers

As software systems evolve, new interface features such as keyboard shortcuts and toolbars are introduced. While it is common to regression test the new features for functional correctness, there has been less focus on systematic regression testing for usability, due to the effort and time involved in human studies. Cognitive modeling tools such as CogTool provide some help by computing predictions of user performance, but they still require manual effort to describe the user interface and tasks, limiting regression testing efforts. In recent work, we developed CogTool-Helper to reduce the effort required to generate human performance models of existing systems. …


Application-Aware Routing For Multi-Hop Cognitive Radio Networks With Channel Bonding, Feng Ye, Jiazhen Zhou, Rose Qingyang Hu 2013 University of Nebraska-Lincoln

Application-Aware Routing For Multi-Hop Cognitive Radio Networks With Channel Bonding, Feng Ye, Jiazhen Zhou, Rose Qingyang Hu

Department of Electrical and Computer Engineering: Faculty Publications

Due to the unequal spectrum resources in different areas, multi-hop wireless cognitive radio network (MWCRN) faces the challenge of a relatively poor performance. In this paper, we propose an application-aware routing scheme with channel bonding technique to help improve the efficiency and performance of a MWCRN network. More specifically, we formulate an optimization problem aiming to meet the application request, as well as operating at low transmission cost. To solve this problem, we first study the greatest lower bound of transmission cost named as Utopian cost, as well as an upper bound of transmission cost. Moreover, we propose two distributed …


Improved Microcontroller-Based Electronic Respiratory Training, Steven A. Parkison, Jay D. Carlson, Lance C. Pérez 2013 University of Nebraska-Lincoln

Improved Microcontroller-Based Electronic Respiratory Training, Steven A. Parkison, Jay D. Carlson, Lance C. Pérez

Department of Electrical and Computer Engineering: Faculty Publications

Respiratory training is a critical component of many rehabilitation plans, including those of stroke patients. Many current respiratory training techniques lack efficient methods for quantifying progress and updating testing parameters. A previously-developed microcontroller-based device, designed in conjunction with clinicians at the Institute for Rehabilitation Science and Engineering at Madonna Rehabilitation Hospital, has demonstrated promising results. Here, a prototype of a revised device that is network connected and remoatly sends trial information is presented.\ The proposed device demonstrates enhanced functionality, while being smaller and using less power than the original prototype.


A Discrete-Time Direct-Torque And Flux Control For Direct-Drive Pmsg Wind Turbines, Zhe Zhang, Yue Zhao, Wei Qiao, Liyan Qu 2013 University of Nebraska-Lincoln

A Discrete-Time Direct-Torque And Flux Control For Direct-Drive Pmsg Wind Turbines, Zhe Zhang, Yue Zhao, Wei Qiao, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

This paper proposes a novel discrete-time direct-torque and flux control (DTFC) scheme for a permanent-magnet synchronous generator (PMSG) used in a variable-speed direct-drive wind power generation system. The proposed DTFC does not rely on machine parameters, such as the inductances and permanent-magnet flux linkage, while the main advantages of the DTC, e.g., fast dynamic response and no need of coordinate transform, are preserved. The stator flux linkage is estimated by an adaptive low-pass filter (LPF), in which a variable cutoff frequency is used. The adaptive LPF stator flux observer can achieve high estimation precision over a wide operating range of …


Model Reference Adaptive System-Based Speed Estimators For Sensorless Control Of Interior Permanent Magnet Synchronous Machines, Yue Zhao, Wei Qiao, Long Wu 2013 University of Nebraska-Lincoln

Model Reference Adaptive System-Based Speed Estimators For Sensorless Control Of Interior Permanent Magnet Synchronous Machines, Yue Zhao, Wei Qiao, Long Wu

Department of Electrical and Computer Engineering: Faculty Publications

In this work, speed estimators are designed based on a model reference adaptive system (MRAS) for sensorless control of interior permanent magnet synchronous machines (IPMSMs). To provide better filtering performance and reduce the noise contents in the estimated speed, an adaptive line enhancer is proposed to work with a sliding-mode observer to provide an improved reference model for speed estimation. In addition, a heterodyning speed adaption scheme is proposed to replace the conventional speed adaption mechanism. The proposed MRASbased speed estimator has two different operating modes, which are suitable for generator- and motor-type applications, respectively. The effectiveness of the proposed …


Broadening The Cloaking Bandwidth With Non-Foster Metasurfaces, Pai-Yen Chen, Christos Argyropoulos, Andrea Alu 2013 University of Texas at Austin

Broadening The Cloaking Bandwidth With Non-Foster Metasurfaces, Pai-Yen Chen, Christos Argyropoulos, Andrea Alu

Department of Electrical and Computer Engineering: Faculty Publications

We introduce the concept and practical design of broadband, ultrathin cloaks based on non-Foster, negatively capacitive metasurfaces. By using properly tailored, active frequency-selective screens conformal to an object, within the realm of a practical realization, we show that it is possible to drastically reduce the scattering over a wide frequency range in the microwave regime, orders of magnitude broader than any available passive cloaking technology. The proposed active cloak may impact not only invisibility and camouflaging, but also practical antenna and sensing applications.


Negative Refraction, Gain And Nonlinear Effects In Hyperbolic Metamaterials, Christos Argyropoulos, Nasim Mohammadi Estakhri, Francesco Monticone, Andrea Alu 2013 University of Texas at Austin

Negative Refraction, Gain And Nonlinear Effects In Hyperbolic Metamaterials, Christos Argyropoulos, Nasim Mohammadi Estakhri, Francesco Monticone, Andrea Alu

Department of Electrical and Computer Engineering: Faculty Publications

The negative refraction and evanescent-wave canalization effects supported by a layered metamaterial structure obtained by alternating dielectric and plasmonic layers is theoretically analyzed. By using a transmission-line analysis, we formulate a way to rapidly analyze the negative refraction operation for given available materials over a broad range of frequencies and design parameters, and we apply it to broaden the bandwidth of negative refraction. Our analytical model is also applied to explore the possibility of employing active layers for loss compensation. Nonlinear dielectrics can also be considered within this approach, and they are explored in order to add tunability to the …


Dnad, A Simple Tool For Automatic Differentiation Of Fortran Codes Using Dual Numbers, Wenbin Yu, Maxwell Blair 2013 Utah State University

Dnad, A Simple Tool For Automatic Differentiation Of Fortran Codes Using Dual Numbers, Wenbin Yu, Maxwell Blair

Mechanical and Aerospace Engineering Faculty Publications

DNAD (dual number automatic differentiation) is a simple, general-purpose tool to automatically differentiate Fortran codes written in modern Fortran (F90/95/2003) or legacy codes written in previous version of the Fortran language. It implements the forward mode of automatic differentiation using the arithmetic of dual numbers and the operator overloading feature of F90/95/2003. Very minimum changes of the source codes are needed to compute the first derivatives of Fortran programs. The advantages of DNAD in comparison to other existing similar computer codes are its programming simplicity, extensibility, and computational efficiency. Specifically, DNAD is more accurate and efficient than the popular complex-step …


A Novel Multirobot Map Fusion Strategy For Occupancy Grid Maps, SEBAHATTİN TOPAL, İSMET ERKMEN, AYDAN MÜŞERREF ERKMEN 2013 TÜBİTAK

A Novel Multirobot Map Fusion Strategy For Occupancy Grid Maps, Sebahatti̇n Topal, İsmet Erkmen, Aydan Müşerref Erkmen

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we consider the problem of merging partial occupancy grid environment maps, which are extracted independently by individual robot units during search and rescue (SAR) operations in icomplex disaster environments. Moreover, these maps are combined using intensity-based and area-based features without knowing the initial position and orientation of the robots. Our proposed approach handles the limitation of existing studies in the literature; for example, the limited overlapped area between partial maps of robots is enough for good merging performance and unstructured and complex partial environment maps can be merged efficiently. These abilities allow multirobot teams to efficiently generate …


A Bacterial Foraging Optimization Approach For Tuning Type-2 Fuzzy Logic Controller, MOHAMMAD KIANI, SEYED MOHAMMAD ALI MOHAMMADI, ALI AKBAR GHARAVEISI 2013 TÜBİTAK

A Bacterial Foraging Optimization Approach For Tuning Type-2 Fuzzy Logic Controller, Mohammad Kiani, Seyed Mohammad Ali Mohammadi, Ali Akbar Gharaveisi

Turkish Journal of Electrical Engineering and Computer Sciences

The type-1 fuzzy sets theory was proposed to handle uncertainty in control systems, but some cases showed some liabilities of type-1 fuzzy sets when faced with unpredictable disturbance and uncertainties. Therefore, type-2 fuzzy sets were introduced and extended while providing more degrees of freedom in designing criteria. The most important specification of type-2 fuzzy sets is the interval between a superior membership function and an inferior membership function, which is called the footprint of uncertainty. This paper presents a bacterial foraging optimization approach for optimizing the parameterized membership function. The above criterion is applied to an automatic voltage regulator system …


A Temporal Xml Data Model In Anaesthesia Information Systems, OYA ÜNLÜ DUYGULU, TAFLAN İMRE GÜNDEM 2013 TÜBİTAK

A Temporal Xml Data Model In Anaesthesia Information Systems, Oya Ünlü Duygulu, Taflan İmre Gündem

Turkish Journal of Electrical Engineering and Computer Sciences

Time information is an important aspect of a health information system. Health information cannot be represented and queried correctly without time in medical research, auditing, and medicolegal cases. Extensible Markup Language (XML) is being used in health information systems and has been formerly proposed as a data model for anaesthesia information systems. In this paper, we propose incorporating time into an XML model for anaesthesia information systems. A new storage structure and a temporal index structure are proposed in order to store temporal XML data and process time queries efficiently. In our proposed model, time has 4 dimensions: valid time, …


Performance Analysis Of Bid Calculation Methods In Multirobot Market-Based Task Allocation, BURAK KALECİ, OSMAN PARLAKTUNA 2013 TÜBİTAK

Performance Analysis Of Bid Calculation Methods In Multirobot Market-Based Task Allocation, Burak Kaleci̇, Osman Parlaktuna

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, the empirical results of a market-based task allocation method for heterogeneous and homogeneous robot teams and different types of tasks in 2 different environments are presented. The proposed method allocates robots to tasks through a parallel multiitem auction-based process. The main contribution of the proposed method is energy-based bid calculations, which take into account both the heterogeneity of the robot team and features of the tasks. The multirobot task allocation problem is considered as the optimal assignment problem and the Hungarian algorithm is used to clear the auctions. Simulations are carried out using energy-based, distance-based, and time-based …


A Word Spotting Method For Farsi Machine-Printed Document Images, YAGHOUB POURASAD, HOUSHANG HASSIBI, AZAM GHORBANI 2013 TÜBİTAK

A Word Spotting Method For Farsi Machine-Printed Document Images, Yaghoub Pourasad, Houshang Hassibi, Azam Ghorbani

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a word spotting approach for Farsi printed document images has been presented. The main idea of the paper is the font recognition of Farsi document images and query word modification according to the document image's font before searching. This operation increases the similarity between the query word image and its instances in the document image; therefore, the performance of the word spotting system increases. In the proposed word spotting approach, after the query word modification, the query word image rectangle is searched in the text lines of the document image using XNOR similarity measurement. In order to …


Investigation Of The Telluric Effects Arising Along The Cathodically Protected Natural Gas Pipeline Between Karadeniz Ereğli And Düzce, BİLAL DEMİREL, HAYRİ YALÇIN 2013 TÜBİTAK

Investigation Of The Telluric Effects Arising Along The Cathodically Protected Natural Gas Pipeline Between Karadeniz Ereğli And Düzce, Bi̇lal Demi̇rel, Hayri̇ Yalçin

Turkish Journal of Electrical Engineering and Computer Sciences

Cathodic protection is one of the most widely used applications for protecting underground and submarine metallic structures from corrosion. This method is based on providing the electrons, which metallic structures lose as a result of electrolytic reaction, by the cathodic protection system. However, from time to time, it may be possible that there is some unwanted interference input into the metallic structure in such applications. This study is aimed at ascertaining the existence, arising frequency, and magnitude of an interference called the telluric effect that is going in and out of the natural gas pipeline between Düzce and Karadeniz Ereğli …


A New Multiobjective Fuzzy Shuffled Frog-Leaping Algorithm For Optimal Reconfiguration Of Radial Distribution Systems In The Presence Of Reactive Power Compensators, HOSSEIN DEHGHAN DEHNAVI, SAEID ESMAEILI 2013 TÜBİTAK

A New Multiobjective Fuzzy Shuffled Frog-Leaping Algorithm For Optimal Reconfiguration Of Radial Distribution Systems In The Presence Of Reactive Power Compensators, Hossein Dehghan Dehnavi, Saeid Esmaeili

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new approach for the optimal reconfiguration of radial distribution systems in the presence of reactive power compensators (RPCs). The proposed method is based on the simultaneous reconfiguration and RPC allocation for the mitigation of losses, equalizing the feeder load balancing as well as improving the voltage profile in power distribution networks. In this paper, the compensators are the capacitor bank and distribution static compensator, which is a type of distribution flexible alternating current transmission system device representative of conventional and modern RPCs. In this regard, the optimal states of the distribution system tie switches are determined …


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