Computer Engineering Commons^™

Wireless Underground Channel Diversity Reception With Multiple Antennas For Internet Of Underground Things, Abdul Salam, Mehmet C. Vuran

School of Computing: Conference and Workshop Papers

Internet of underground things (IOUT) is an emerging paradigm which consists of sensors and communication devices, partly or completely buried underground for real-time soil sensing and monitoring. In this paper, the performance of different modulation schemes in IOUT communications is studied through simulations and experiments. The spatial modularity of direct, lateral, and reflected components of the UG channel is exploited by using multiple antennas. First, it has been shown that bit error rates of $10^{-3}$ can be achieved with normalized delay spreads ($\tau_d$) lower than $0.05$. Evaluations are conducted through the first software-defined radio-based field experiments for UG channel. Moreover, …

Towards Internet Of Underground Things In Smart Lighting: A Statistical Model Of Wireless Underground Channel, Abdul Salam, Mehmet C. Vuran, Suat Irmak

School of Computing: Conference and Workshop Papers

The Internet of Underground Things (IOUT) has many applications in the area of smart lighting. IOUT enables communications in smart lighting through underground (UG) and aboveground (AG) communication channels. In IOUT communications, an in-depth analysis of the wireless underground channel is important to design smart lighting solutions. In this paper, based on the empirical and the statistical analysis, a statistical channel model for the UG channel has been developed. The parameters for the statistical tapped-delay-line model are extracted from the measured power delay profiles (PDP). The PDP of the UG channel is represented by the exponential decay of the lateral, …

Smart Underground Antenna Arrays: A Soil Moisture Adaptive Beamforming Approach, Abdul Salam, Mehmet C. Vuran

School of Computing: Conference and Workshop Papers

Current wireless underground (UG) communication techniques are limited by their achievable distance. In this paper, a novel framework for underground beamforming using adaptive antenna arrays is presented to extend communication distances for practical applications. Based on the analysis of propagation in wireless underground channel, a theoretical model is developed which uses soil moisture information to improve wireless underground communications performance. Array element in soil is analyzed empirically and impacts of soil type and soil moisture on return loss (RL) and resonant frequency are investigated. Accordingly, beam patterns are analyzed to communicate with underground and above ground devices. Depending on the …

Biosimp: Using Software Testing Techniques For Sampling And Inference In Biological Organisms, Mikaela Cashman, Jennie L. Catlett, Myra B. Cohen, Nicole R. Buan, Zahmeeth Sakkaff, Massimiliano Pierobon, Christine A. Kelley

School of Computing: Conference and Workshop Papers

Years of research in software engineering have given us novel ways to reason about, test, and predict the behavior of complex software systems that contain hundreds of thousands of lines of code. Many of these techniques have been inspired by nature such as genetic algorithms, swarm intelligence, and ant colony optimization. In this paper we reverse the direction and present BioSIMP, a process that models and predicts the behavior of biological organisms to aid in the emerging field of systems biology. It utilizes techniques from testing and modeling of highly-configurable software systems. Using both experimental and simulation data we show …

In-Situ Terahertz Optical Hall Effect Measurements Of Ambient Effects On Free Charge Carrier Properties Of Epitaxial Graphene, Sean Knight, Tino Hofmann, Chamseddine Bouhafs, Nerijus Armakavicius, Philipp Kühne, Vallery Stanishev, Ivan G. Ivanov, Rositsa Yakimova, Shawn Wimer, Mathias Schubert, Vanya Darakchieva

Department of Electrical and Computer Engineering: Faculty Publications

Unraveling the doping-related charge carrier scattering mechanisms in two-dimensional materials such as graphene is vital for limiting parasitic electrical conductivity losses in future electronic applications. While electric field doping is well understood, assessment of mobility and density as a function of chemical doping remained a challenge thus far. In this work, we investigate the effects of cyclically exposing epitaxial graphene to controlled inert gases and ambient humidity conditions, while measuring the Lorentz force-induced birefringence in graphene at Terahertz frequencies in magnetic fields. This technique, previously identified as the optical analogue of the electrical Hall effect, permits here measurement of charge …

Rainbow Peacock Spiders Inspire Miniature Superiridescent Optics, Bor-Kai Hsiung, Radwanul Hasan Siddique, Doekele G. Stavenga, Jürgen C. Otto, Michael C. Allen, Ying Liu, Yongfeng Lu, Dimitri D. Deheyn, Matthew D. Shawkey, Todd A. Blackledge

Department of Electrical and Computer Engineering: Faculty Publications

Colour produced by wavelength-dependent light scattering is a key component of visual communication in nature and acts particularly strongly in visual signalling by structurallycoloured animals during courtship. Two miniature peacock spiders (Maratus robinsoni and M. chrysomelas) court females using tiny structured scales (~ 40 × 10 μm²) that reflect the full visual spectrum. Using TEM and optical modelling, we show that the spiders’ scales have 2D nanogratings on microscale 3D convex surfaces with at least twice the resolving power of a conventional 2D diffraction grating of the same period. Whereas the long optical path lengths required …

Controllable Plasmonic Nanostructures Induced By Dual-Wavelength Femtosecond Laser Irradiation, Weina Han, Lan Jiang, Xiaowei Li, Qingsong Wang, Shaojun Wang, Jie Hu, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

We demonstrated an abnormal double-peak (annular shaped) energy deposition through dualwavelength synthesis of the fundamental frequency (ω) and the second-harmonic frequency (2ω) of a femtosecond (fs) Ti:sapphire laser. The annular shaped distribution of the dual-wavelength fs laser was confirmed through real beam shape detection. This uniquely simple and flexible technique enables the formation of functional plasmonic nanostructures. We applied this double-peak fs-laser-induced dewetting effect to the controlled fabrication and precise deposition of Au nanostructures, by using a simple, lithography-free, and single-step process. In this process, the double-peak energy-shaped fs laser pulse induces surface patterning of a thin film followed by …

Preparation Of Monolayer Mos2 Quantum Dots Using Temporally Shaped Femtosecond Laser Ablation Of Bulk Mos2 Targets In Water, Bo Li, Lan Jiang, Xin Li, Peng Ran, Pei Zuo, Andong Wang, Liangti Qu, Yang Zhao, Zhihua Cheng, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

Zero-dimensional MoS₂ quantum dots (QDs) possess distinct physical and chemical properties, which have garnered them considerable attention and facilitates their use in a broad range of applications. In this study, we prepared monolayer MoS₂ QDs using temporally shaped femtosecond laser ablation of bulk MoS₂ targets in water. The morphology, crystal structures, chemical, and optical properties of the MoS₂ QDs were characterized by transmission electron microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, UV–vis absorption spectra, and photoluminescence spectra. The analysis results show that highly pure, uniform, and monolayer MoS₂ QDs can be successfully prepared. Moreover, …

Tunable Subnanometer Gap Plasmonic Metasurfaces, Dennis Doyle, Nicholas Charipar, Christos Argyropoulos, Scott A. Trammell, Rafaela Nita, Jawad Naciri, Alberto Piqué, Joseph B. Herzog, Jake Fontana

Department of Electrical and Computer Engineering: Faculty Publications

The index of refraction governs the flow of light through materials. At visible and near-infrared wavelengths the real part of the refractive index is limited to less than 3 for naturally occurring transparent materials, fundamentally restricting applications. Here, we carried out experiments to study the upper limit of the effective refractive index of self-assembled metasurfaces at visible and near-infrared wavelengths. The centimeter-scale metasurfaces were made of a hexagonally close packed (HCP) monolayer of gold nanospheres coated with tunable alkanethiol ligand shells, controlling the interparticle gap from 2.8 to 0.45 nm. In contrast to isolated dimer studies, the macroscale areas allow …

Flatland Plasmonics And Nanophotonics Based On Graphene And Beyond, Pai-Yen Chen, Christos Argyropoulos, Mohamed Farhat, J. Sebastian Gomez-Diaz

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, we review and discuss how the recently discovered two-dimensional (2D) Dirac materials, particularly graphene, may be utilized as new efficient platforms for excitations of propagating and localized surface plasmon polaritons (SPPs) in the terahertz (THz) and mid-infrared (MIR) regions. The surface plasmon modes supported by the metallic 2D materials exhibit tunable plasmon resonances that are essential, yet missing, ingredients needed for THz and MIR photonic and optoelectronic devices. We describe how the atomically thin graphene monolayer and metamaterial structures based on it may tailor and control the spectral, spatial, and temporal properties of electromagnetic radiation. In the …

Decreased Home Cage Movement And Oromotor Impairments In Adult Fmr1-Ko Mice, Stephen J. Bonasera, Tammy R. Chaudoin, Evan H. Goulding, Mateusz Mittek, Anna Dunaevsky

Department of Electrical and Computer Engineering: Faculty Publications

Fragile X syndrome (FXS) is a common inherited disorder that significantly impacts family and patient day-to-day living across the entire lifespan. The childhood and adolescent behavioral consequences of FXS are well-appreciated. However, there are significantly fewer studies (except those examining psychiatric comorbidities) assessing behavioral phenotypes seen in adults with FXS. Mice engineered with a genetic lesion of Fmr1 recapitulate important molecular and neuroanatomical characteristics of FXS, and provide a means to evaluate adult behavioral phenotypes associated with FXS. We give the first description of baseline behaviors including feeding, drinking, movement, and their circadian rhythms; all observed over 16 consecutive days …

Higher C-Reactive Protein Levels Predict Postoperative Delirium In Older Patients Undergoing Major Elective Surgery: A Longitudinal Nested Case-Control Study, Simon T. Dillon, Sarinnapha M. Vasunilashorn, Long Ngo, Hasan H. Otu, Sharon K. Inouye, Richard N. Jones, David C. Alsop, George A. Kuchel, Eran D. Metzger, Steven E. Arnold, Edward R. Marcantonio, Towia A. Libermann

Department of Electrical and Computer Engineering: Faculty Publications

Background—Delirium is a common, morbid, and costly postoperative complication.. We aimed to identify blood-based postoperative delirium markers in a nested case control study of older surgical patients using a proteomics approach followed by enzyme-linked immunosorbent assay (ELISA) validation.

Methods and Materials—The Successful Aging after Elective Surgery Study enrolled dementia-free adults age ≥70 undergoing major scheduled non-cardiac surgery (N=566; 24% delirium). Plasma was collected at 4 timepoints: preoperatively (PREOP), post-anesthesia care unit (PACU), postoperative day 2 (POD2) and 1 month follow-up (PO1MO). Matched pairs were selected for the independent discovery (39 pairs) and replication cohorts (36 pairs), which were …

Correction: Genomic Counter-Stress Changes Induced By The Relaxation Response, Jeffery A. Dusek, Hasan H. Otu, Ann L. Wohlhueter, Manoj Bhasin, Luiz F. Zerbini, Marie G. Joseph, Herbert Benson, Towia A. Libermann

Department of Electrical and Computer Engineering: Faculty Publications

The Competing Interests statement is incorrect. The correct Competing Interests statement is: The following authors hold or have held positions at the Benson-Henry Institute for Mind Body Medicine at Massachusetts General Hospital, which is paid by patients and their insurers for running the SMART-3RP and related relaxation/mindfulness clinical programs, markets related products such as books, DVDs, CDs and the like, and holds a patent pending (PCT/ US2012/049539 filed August 3, 2012) entitled "Quantitative Genomics of the Relaxation Response": JAD, ALW, HB.

Formation Of Aggregated Nanoparticle Spheres Through Femtosecond Laser Surface Processing, Alfred T. Tsubaki, Mark A. Koten, Michael J. Lucis, Craig Zuhlke, Natale J. Ianno, Jeffrey E. Shield, Dennis R. Alexander

Department of Electrical and Computer Engineering: Faculty Publications

A detailed structural and chemical analysis of a class of self-organized surface structures, termed aggregated nanoparticle spheres (AN-spheres), created using femtosecond laser surface processing (FLSP) on silicon, silicon carbide, and aluminum is reported in this paper. AN-spheres are spherical microstructures that are 20–100 μm in diameter and are composed entirely of nanoparticles produced during femtosecond laser ablation of material. AN-spheres have an onion-like layered morphology resulting from the build-up of nanoparticle layers over multiple passes of the laser beam. The material properties and chemical composition of the AN-spheres are presented in this paper based on scanning electron microscopy (SEM), focused …

Direct Torque Control Of Ac Electric Machines, Wei Qiao, Zhe Zhang, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

This disclosure features an apparatus including a motor controller to generate control signals to control an electric motor. The motor controller includes a first saturation controller to generate a first saturation controller output based on feedback signals associated with the electric motor. The motor controller further includes a duty ratio modulator coupled to the first saturation controller. The duty ratio modulator is configured to determine activation times for a set of voltage vectors based on the first saturation controller output. The motor controller is configured to generate, at each switching cycle, a control signal based on the set of voltage …

Brief Study Of Classification Algorithms In Machine Learning, Ramesh Sankara Subbu

Dissertations and Theses

The purpose of this study is to briefly learn the theory and implementation of three most commonly used Machine Learning algorithms: k-Nearest Neighbors (kNN), Decision Trees and Naïve Bayes. All these algorithms fall under the Classification algorithm category of Unsupervised Machine Learning. This paper is constructed structurally in explaining the working theory behind each algorithm and an implementation of a Machine Learning problem solved by each algorithm. KNN algorithm is designed using Euclidean distance measurement and Decision Trees make use of ID3 algorithm as a basis. We conclude the study by providing an overall picture of its strengths and weaknesses …

A Dynamic Scaling Methodology For Improving Performance Of Big Data Systems, Nashmiah Alhamdawi

Electronic Theses and Dissertations

The continuous growth of data volume in various fields such as, healthcare, sciences, economics, and business has caused an overwhelming flow of data in the last decade. The overwhelming flow of data has raised challenges in processing, analyzing, and storing data, which lead many systems to face an issue in performance. Poor performance of systems creates negative impact such as delays, unprocessed data, and increasing response time. Processing huge amounts of data demands a powerful computational infrastructure to ensure that data processing and analysis success [7]. However, the architectures of these systems are not suitable to process that quantity of …

Availability Of Datasets For Digital Forensics–And What Is Missing, Cinthya Grajeda, Frank Breitinger, Ibrahim Baggili

Electrical & Computer Engineering and Computer Science Faculty Publications

This paper targets two main goals. First, we want to provide an overview of available datasets that can be used by researchers and where to find them. Second, we want to stress the importance of sharing datasets to allow researchers to replicate results and improve the state of the art. To answer the first goal, we analyzed 715 peer-reviewed research articles from 2010 to 2015 with focus and relevance to digital forensics to see what datasets are available and focused on three major aspects: (1) the origin of the dataset (e.g., real world vs. synthetic), (2) if datasets were released …

A High Performance Hysteresis Current Control Of A Permanent Magnet Synchronous Motor Drive, Cosmas Ogbuka, Cajethan Nwosu, Marcel Agu

Turkish Journal of Electrical Engineering and Computer Sciences

A high performance hysteresis current control of a permanent magnet synchronous motor (PMSM) drive is developed in this paper. The core advantage of field orientation control (FOC) is utilized to separate the flux and torque control components of the stator current of the PMSM. Specifically, the objectives of this work are to develop and utilize the HCC algorithm for FOC of a complete closed-loop speed-controlled PMSM drive system, optimize the control algorithm to obtain fast speed response while maintaining effective current and torque tracking, and examine the hysteresis current control action clearly showing the inverter switching and the effects of …

Comparison Of Group Key Establishment Protocols, Serap Şahi̇n, Rabi̇a Aslanoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Recently group-oriented applications over unsecure open networks such as Internet or wireless networks have become very popular. Thus, group communication security over unsecure open networks has become a vital concern. Group key establishment (GKE) protocols are used to satisfy the confidentiality requirement of a newly started communication session by the generation or sharing of an ephemeral common key between the group members. In this study, we analyze the computation and communication efficiency of GKE protocols. Besides confidentiality, the security characteristics of identification and integrity control are also required for all steps of the protocol implementations. Thus, the main contribution of …

Robust Adaptive Fuzzy Control Of A Three-Phase Active Power Filter Based On Feedback Linearization, Shixi Hou, Juntao Fei

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a robust adaptive fuzzy control system using feedback linearization is proposed for a three-phase active power filter (APF). The APF system is divided into two separate loops: the current dynamic inner loop and the DC voltage dynamic outer loop. Adaptive fuzzy tracking control using feedback linearization is employed for the current dynamic inner loop to overcome the drawbacks of the conventional method. The proposed controller can ensure proper tracking of the reference current and impose desired dynamic behavior, giving robustness and insensitivity to parameter variations. Adaptive fuzzy proportional-integral control is applied to the DC voltage dynamics outer …

Novel Scheduling Algorithm For Optimizing Real-Time Multimedia Performance In Long Term Evolution-Advanced, Huda Adibah Mohd Ramli, Zairi Ismael Rizman

Turkish Journal of Electrical Engineering and Computer Sciences

Real-time multimedia applications are becoming increasingly popular among mobile cellular users. Given that Long Term Evolution-Advanced (LTE-A), which is an emerging mobile cellular standard, needs to support these multimedia applications, packet scheduling is of paramount importance in LTE-A. This paper proposes a packet scheduling algorithm known as novel scheduling for usage in the downlink of LTE-A. It takes channel quality, average throughput, and packet delay into account when determining the priority of each user. Simulation results demonstrate the efficacy of the proposed algorithm in optimizing real-time multimedia performance for more mobile cellular users.

Sotarm: Size Of Transaction-Based Association Rule Mining Algorithm, Asha Pandian, Jebarajan Thaveethu

Turkish Journal of Electrical Engineering and Computer Sciences

Mining of association rules tries to identify the existence of promising and fruitful relations among the items present in a database. The basic a priori algorithm suffers from multiple database scans, and if the database is large, then the time taken for scanning and generation of candidates is also large. The proposed algorithm attempts to reduce the repeated scanning of the whole database. Using this algorithm, scanning time and also the generation of subitems that are not frequent can be reduced. The former can be done by sorting the transaction records in descending order based on the size of transaction …

A Hybrid Maco And Bfoa Algorithm For Power Loss Minimization And Total Cost Reduction In Distribution Systems, Muthubalaji Sankaramoorthy, Malathi Veluchamy

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a multiobjective optimization methodology to optimally place a STATCOM in electric power distribution networks. The combination of multiobjective ant colony optimization (MACO) and the bacterial foraging optimization algorithm (BFOA) is proposed to minimize the power loss and total cost. The main intention of this analysis is to optimally place the STATCOM at multiple locations such as the transmission side, middle, and load side. Identifying the type and location of the STATCOM is a combinatorial optimization problem in power systems. In order to overcome this problem, the combination of hybrid MACO and BFOA algorithms is applied in this …

An Intelligent Approach In Delay Tolerant Network Routing, Azadeh Omidvar, Karim Mohammadi

Turkish Journal of Electrical Engineering and Computer Sciences

Delay tolerant networks (DTNs) are wireless intermittent networks. DTNs have different applications such as wildlife tracking, military, and space searching. Conventional mobile ad hoc network (MANET) routing protocols are not efficient in these networks because of intermittency. DTNs use store-carry-forward (SCF) for data transferring. In SCF, nodes store the messages and carry them until finding appropriate nodes for forwarding. Message replication greatly helps to improve the delivery ratio while increasing overhead. This paper examines the use of intelligent routing to choose nodes that have more probability to reach their destination. This will help to increase the message delivery ratio while …

Implementation Of Svc Based On Grey Theory And Fuzzy Logic To Improve Lvrt Capability Of Wind Distributed Generations, Mohammad Mehdi Karami, Akbar Itami

Turkish Journal of Electrical Engineering and Computer Sciences

Due to the great absorption of reactive power after voltage drops caused by faults in network, the low-voltage ride through (LVRT) capability of squirrel cage induction generators (SCIGs) in wind farms is a great challenge. If a static VAR compensator (SVC) is installed at the point of common coupling (PCC) of a wind farm with a main network, it can improve the wind generation's LVRT capability with reactive power compensation. In the voltage control loop of a conventional SVC, the voltage actual value of the PCC is compared with the reference voltage value. This paper presents a method for implementation …

A New Efficient Block Matching Data Hiding Method Based On Scanning Order Selection In Medical Images, Turgay Aydoğan, Cüneyt Bayilmiş

Turkish Journal of Electrical Engineering and Computer Sciences

Digital technology and the widespread use of the Internet has increased the speeds at which digital data can be obtained and shared in daily life. In parallel to this, there are important concerns regarding the confidentiality of private data during data transmissions and the possibility that data might fall into the hands of third parties. Issues relating to data safety can also affect patients' medical images and other information relating to these images. In this study, we propose a new method based on block matching that can be used to hide the patient information in medical images. In this method, …

Adaptive Control Of Pure-Feedback Systems In The Presence Of Parametric Uncertainties, Mehrnoosh Asadi, Heydar Toossian Shandiz

Turkish Journal of Electrical Engineering and Computer Sciences

The purpose of this study is to investigate an adaptive control approach for completely nonaffine pure-feedback systems with linear/nonlinear parameterization. In this approach, the parameter separation technique and the idea of the positive function of linearly connected parameters are coupled effectively with the combination of backstepping and time-scale separation. Subsequently, a fast dynamical equation is derived from the original subsystem, where the solution is sought to approximate the corresponding ideal virtual/actual control inputs. Furthermore, the adaptation law of unknown parameters can be derived based on Lyapunov theory in the backstepping technique and there is no need to design a state …

Design Of A Three-Phase Multistage Axial Flux Permanent Magnet Generator For Wind Turbine Applications, Muhammad Mansoor Ashraf, Tahir Nadeem Malik

Turkish Journal of Electrical Engineering and Computer Sciences

Presently, axial flux permanent magnet machines are becoming popular and are being deployed actively for low speed applications. This paper presents an improved model of a multistage axial flux permanent magnet generator (AFPMG). The multistage AFPMG consists of multiple stator and rotor discs. There are three identical 1-phase stator discs and four in-phase rotor discs in the proposed multistage AFPMG. In this research, 4 case studies were analyzed on the design of the multistage AFPMG. First, a phase shift model (PSM) positions the three 1-phase stator discs to behave as a 3-phase generator. Actually, the PSM computes phases for three …

Transmission Power Control Using State Estimation-Based Received Signal Strength Prediction For Energy Efficiency In Wireless Sensor Networks, Ramakrishnan Sabitha, Krishna Bhuma, Thangavelu Thyagarajan

Turkish Journal of Electrical Engineering and Computer Sciences

In battery-operated wireless sensor networks, the quality of service requirements such as throughput and energy efficiency must be stringently maintained while the least amount of energy is consumed. Since a major portion of energy is spent by the transceiver operations, transmission power control (TPC) in the medium access control (MAC) layer can bring about considerable energy efficiency. Since TPC algorithms will have a direct impact on the received signal strength index (RSSI) at the receiver, RSSI is the primary input parameter for any TPC algorithm. The objective of the proposed work is to decide on the exact value of transmission …