Generation Of Bipolar Nanosecond Pulses,
2014
Old Dominion University
Generation Of Bipolar Nanosecond Pulses, Sambasiva Rao Rajulapati
Electrical & Computer Engineering Theses & Dissertations
Bipolar pulse generation has been studied using transmission line technology, which was mainly used for monopolar pulse generation. In this thesis, low impedance, high current, nanosecond pulse generators were designed, constructed and tested. Five transmission lines were connected in parallel, so the impedance was 10 n. The transmission lines were switched by a spark gap switch operated in air. The closing of the switch creates a matched condition on one side of the transmission lines and a short circuit on the other side of the transmission lines. When the transmission lines are precharged, one of the two waves in opposite …
Effect Of Image Capture Devices On The Accuracy Of Black-Box Printer Models,
2014
Purdue University
Effect Of Image Capture Devices On The Accuracy Of Black-Box Printer Models, Jae Sung Youn
Open Access Theses
In the process of electrophotograpic (EP) printing, the deposition of toner to the printer-addressable pixel is greatly influenced by the neighboring pixels of the digital halftone. To account for these effects, printer models can either be embedded in the halftoning algorithm, or used to predict the printed halftone image at the input to an algorithm being used to assess print quality. Most recently, a series of six new models were developed to accurately account for local neighborhood effects and the influence of a 45 × 45 neighborhood of pixels on the central printer-addressable pixel. All these models are referred to …
Studies In Software-Defined Radio System Implementation,
2014
Liberty University
Studies In Software-Defined Radio System Implementation, Harold A. Haldren Iii
Senior Honors Theses
Over the past decade, software-defined radios (SDRs) have an increasingly prevalent aspect of wireless communication systems. Different than traditional hardware radios which implement radio protocols using static electrical circuit, SDRs implement significant aspects of physical radio protocol using software programs running on a host processor. Because they use software to implement most of the radio functionality, SDRs are much more easily modified, edited, and upgraded than their hardware-defined counterparts. Consequently, researchers and developers have been developing previously hardware-defined radio systems within software. Thus, communication standards can be tested under different conditions or swapped out entirely by simply changing some code. …
Dynamic Characteristic Identification Of Seismic-Excited Multi-Story Buildings Through Response-Only Technique,
2014
Department of Civil Engineering, Institut Teknologi Sepuluh Nopember, Surabaya 60116, Indonesia
Dynamic Characteristic Identification Of Seismic-Excited Multi-Story Buildings Through Response-Only Technique, Agung Budipriyanto, Priyo Suprobo
Makara Journal of Technology
Identifying dynamic characteristics of civil engineering structures is still a challenging task. It intends to assess behavior of the structures under time-dependent loads. This paper discusses a methodology suitable for identifying the characteristics of multi-story buildings using only their measured response under earthquake ground excitations. Appropriateness of technique used for structural identification was corroborated through coherence of the structure’s responses. The methodology was applied for identifying the characteristics of 14-story and 20-story office buildings located in a high seismic region. Responses of these two buildings recorded during three different seismic ground motions were investigated. The buildings’ response spectral densities and …
Synthesis And Characterization Of Soy-Based Polyurethane Foam With Utilization Of Ethylene Glycol In Polyol,
2014
Department of Chemical Engineering, Jayabaya University, Jakarta Timur 13210, Indonesia
Synthesis And Characterization Of Soy-Based Polyurethane Foam With Utilization Of Ethylene Glycol In Polyol, Flora Elvistia Firdaus
Makara Journal of Technology
The use of vegetable oils on replacing petroleum has attracted attention of many researchers. The chemical structure of vegetable oils are different from petrochemicals, so the structure of soybean oil has to be chemically modified through its unsaturated fatty acid chain in triglyceride. A two step process was conducted for the preparation of soy-polyol in designated temperatures; 50 °C, 60 °C, and 70 °C. Ethylene glycol (EG) as co-reagent was taking part in soy-polyol synthesis, and the soy-polyol was used as a sole polyol for polyurethane synthesis. Referred to the previous study, the existence of EG in polyurethane synthesis can …
Performances Of Free-Space Optical Communication System Over Strong Turbulence,
2014
Study Program of Opto-Electrotechnique & Laser Application, Department of Electrical Engineering, Faculty of Engineering, Universitas Indonesia, Depok 16425, Indonesia
Performances Of Free-Space Optical Communication System Over Strong Turbulence, Ucuk Darusalam, Purnomo Sidi Priambodo, Harry Sudibyo, Eko Tjipto Rahardjo
Makara Journal of Technology
We report an experimental of free-space optical communication (FSOC) system that use tube propagation simulator (TPS) as the turbulence medium. The FSOC system use wavelength of 1550 nm at the rate transmission of 1000 Mbps and amplified with EDFA at the output of +23 dBm. Index structure of 10-15–10-13 as the representation of atmosphere index turbulences are used for simulation of intensity distribution model or scintillation. The simulation use gammagamma and K model as well. The beam wave propagation models used in simulation are plane wave, spherical wave and Gaussian wave. Spherical wave achieves highest performance via gamma-gamma in strong …
Preparations Of Nanostructured Silicide Bundles And Oxide Arrays,
2014
Faculty of Engineering, Shizuoka University, Hamamatsu 432-8011 Japan
Preparations Of Nanostructured Silicide Bundles And Oxide Arrays, Hirokazu Tatsuoka, Wen Li, Erchao Meng, Daisuke Ishikwa, Kaito Nakane, Shingo Oda, Tomoji Matsushita, Natsuki Kurebayashi
Makara Journal of Technology
A variety of nanostructured silicide bundles and oxide nanowire arrays with abundant, non-toxic materials we are prepared. The CrSi2 nanowire and Mg2Si/MgO composite nanowire bundles were synthesized using a Si substrate and a SiOx nanofiber bundle, respectively. The hexagonal MoSi2 nanosheet bundles were also synthesized using a MoS2 layered material as a template. In addition, ZnO, CuO/Cu2O and a-Fe2O3 nanowire arrays were prepared on semiconductor or metallic substrates. The growth phenomena and the structural properties of the nanostructured materials awere investigated. In addition, the preparations of axial and radial nanowire structures weare examined.
Bioethanol Production From Iles-Iles And Sorghum Starch As Raw Materials (Effect Of Cacl 2 Addition And Saccharification Time),
2014
Renewable Energy Research Centre, Muhammadiyah University of Surakarta, Surakarta 57102, Indonesia
Bioethanol Production From Iles-Iles And Sorghum Starch As Raw Materials (Effect Of Cacl 2 Addition And Saccharification Time), Kusmiyati Kusmiyati, Ali Mahmudi
Makara Journal of Technology
Bioethanol produced from agricultural sources is one alternative energy that has been developed to substitute for petroleum. However, the use of food sources such as corn and cassava to produce bioethanol still face obstacles that lead to the scarcity of food and an increase in food prices. The aim of this study was to produce bioethanol from sorghum and iles-iles, which are not used by humans as food, especially in Indonesia. For both materials, the variables studied were saccharification time (4, 8, 24, and 48 h) and concentration of CaCl2 added to the liquefaction slurry (0, 100, 200, 300, and …
The Effect Of Zephyr Layer Orientation On Zephyrboard Made From Oil Palm Petiole,
2014
Forest Product Department, Institut Pertanian Bogor, Bogor 16001, Indonesia
The Effect Of Zephyr Layer Orientation On Zephyrboard Made From Oil Palm Petiole, Lusita Wardani, Muhamad Yusram Massijaya, Yusuf Sudo Hadi, I Wayan Darmawan
Makara Journal of Technology
It is very important to utilize oil palm petiole for the production of zephyr boards. This study aimed to analyze the effect of layer orientation on zephyr board quality. Zephyr boards were made with three coating patterns (A = cross perpendicular, B= combine A and C, and C= paralell) and five zephyr layers using urea formaldehyde adhesive. They were pressed for 20 min at a pressure of 25 kgf/cm² and a temperature 120 ºC, to a target density of 0.80 g/cm³ and a size of 300 mm X 300 mm X 12 mm. Our results showed that the physical and …
Performance Evaluation Of An Optimized Floating Breakwater In Oblique Waves With A Higher-Order Boundary Element Method,
2014
Department of Naval Architecture, Faculty of Engineering, Universitas Hasanuddin, Makassar 90245, Indonesia
Performance Evaluation Of An Optimized Floating Breakwater In Oblique Waves With A Higher-Order Boundary Element Method, Faisal Mahmuddin, Masashi Kashiwagi
Makara Journal of Technology
In the previous study, the optimal performance of a two-dimensional (2D) floating breakwater shape was obtained. The performance of this shape was also confirmed with a model experiment in a towing tank. Moreover, the shape’s performance in three dimensions (3D) was investigated in a subsequent study. However, to predict the shape’s performance in a real application more accurately, the shape’s characteristics in oblique waves must also be evaluated. In this study, the performance and characteristics of the model (hydrodynamic forces, body motions, wave elevations, and drift forces) are computed using a higher-order boundary element method (HOBEM). The HOBEM, which is …
Position/Speed Sensorless Control For Permanent-Magnet Synchronous Machines,
2014
University of Nebraska-Lincoln
Position/Speed Sensorless Control For Permanent-Magnet Synchronous Machines, Yue Zhao
Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research
Permanent-magnet synchronous machines (PMSMs) are widely used in industrial applications owing to their distinctive advantages, such as high efficiency, high power density, and wide constant power region. To achieve high-performance field oriented control, accurate rotor position information, which is usually measured by rotary encoders or resolvers, is indispensable. However, the use of these sensors increases the cost, size, weight, and wiring complexity and reduces the mechanical robustness and the reliability of the overall PMSM drive systems. The goal of the research for this dissertation was to develop a rotor position/speed sensorless control system with performance comparable to the sensor-based control …
Memristor-Based Neuron Circuit And Method For Applying Learning Algorithm In Spice,
2014
University of Dayton
Memristor-Based Neuron Circuit And Method For Applying Learning Algorithm In Spice, Christopher Yakopcic, R. Hasan, T.M. Taha, M. Mclean, D. Palmer
Electrical and Computer Engineering Faculty Publications
The learning of nonlinearly separable functions in cascaded memristor crossbar circuits is described and the feasibility of using them to develop low-power neuromorphic processors is demonstrated. This is the first study evaluating the training of memristor crossbars through SPICE simulations. It is important to capture the alternate current paths and wire resistance inherent in these circuits. The simulations show that neural network learning algorithms are able to train in the presence of alternate current paths and wire resistances. The fact that the approach reduces the area by three times and power by two orders of magnitude compared with the existing …
Blind Demodulation Of Pass Band Ofdma Signals And Jamming Battle Damage Assessment Utilizing Link Adaptation,
2014
Air Force Institute of Technology
Blind Demodulation Of Pass Band Ofdma Signals And Jamming Battle Damage Assessment Utilizing Link Adaptation, Nicholas A. Rutherford
Theses and Dissertations
This research focuses on blind demodulation of a pass band OFDMA signal so that jamming effectiveness can be assessed; referred to in this research as BDA. The research extends, modifies and collates work within literature to perform a new method of blindly demodulating of a passband OFDMA signal, which exhibits properties of the 802.16 Wireless MAN OFDMA standard, and presents a novel method for performing BDA via observation of SC LA. Blind demodulation is achieved by estimating the carrier frequency, sampling rate, pulse shaping filter roll off factor, synchronization parameters and CFO. The blind demodulator's performance in AWGN and a …
Characterization And Performance Comparison Of Low-Voltage, High-Speed, Push-Pull And Traveling-Wave Silicon Mach-Zehnder Modulators,
2014
Air Force Institute of Technology
Characterization And Performance Comparison Of Low-Voltage, High-Speed, Push-Pull And Traveling-Wave Silicon Mach-Zehnder Modulators, Tristan A. Latchu
Theses and Dissertations
The well-known power and memory walls are recognized as the current bottlenecks in computing performance, and with the increasing computational load of commonly run applications, it is necessary to nd ways to alleviate the issues presented by the aforementioned bottlenecks. It is therefore necessary to not focus solely on extracting performance improvement by way of changes to the processing architecture, but rather by holistically improving the computing platform, namely the communications backbone. This work focuses on the characterization and performance comparison of two families of optical data modulators, both fundamentally Mach{Zehnder modulators (MZMs); namely, a modulator with a Push-Pull (PP) …
Selectively Tuning A Buckled Si/Sio2 Membrane Mems Through Joule Heating Actuation And Mechanical Restriction,
2014
Air Force Institute of Technology
Selectively Tuning A Buckled Si/Sio2 Membrane Mems Through Joule Heating Actuation And Mechanical Restriction, Kyle K. Ziegler
Theses and Dissertations
This research followed previous work and attempted to modify the spring in two ways. First, a Ti/Au meander resistor was deposited atop the membrane in an effort to actuate the membrane and change the spring constant. Secondly, a series of overhanging cantilevers were attached to the bulk substrate surrounding the membrane in an effort to constrain the membrane buckling deflection to the negative stiffness region. Membrane buckling was investigated through Finite Element analysis (FEA) and analytical equations. Deflections were measured using an interferometric microscope (IFM) and force/deflection measurements were captured using a unique measurement scheme. The results concluded that by …
Removing Parallax-Induced False Changes In Change Detection,
2014
Air Force Institute of Technology
Removing Parallax-Induced False Changes In Change Detection, Karmon M. Vongsy
Theses and Dissertations
Accurate change detection (CD) results in urban environments is of interest to a diverse set of applications including military surveillance, environmental monitoring, and urban development. This work presents a hyperspectral CD (HSCD) framework. The framework uncovers the need for HSCD methods that resolve false change caused by image parallax. A Generalized Likelihood Ratio Test (GLRT) statistic for HSCD is developed that accommodates unknown mis-registration between imagery described by a prior probability density function for the spatial mis-registration. The potential of the derived method to incorporate more complex signal proccessing functions is demonstrated by the incorporation of a parallax error mitigation …
Electrical Characterization Of Spherical Copper Oxide Memristive Array Sensors,
2014
Air Force Institute of Technology
Electrical Characterization Of Spherical Copper Oxide Memristive Array Sensors, James P. Orta
Theses and Dissertations
A new System Protection (SP) technology is explored by using electrical and mechanical interference-sensing devices that are implemented with granular memristive material. The granular materials consist of oxide-coated copper spheres with radii of about 700 µm that are placed in contact to produce thin oxide junctions which exhibit memristive behavior. Processes for etching, which compared acetic acid and nitric acid etches, and thermal oxidation at 100°C are performed and compared to produce copper spheres with a copper oxide layer over the sphere surface. Oxidized copper spheres are tested as sensor arrays by loading into a capillary tube in an aligned …
Memristive Responses Of Jammed Granular Copper Array Sensors To Mechanical Stress,
2014
Air Force Institute of Technology
Memristive Responses Of Jammed Granular Copper Array Sensors To Mechanical Stress, Gary A. Willey
Theses and Dissertations
A granular memristive device with the end goal of creating a novel system protection device is introduced in a 1-Dimension array. The electromechanical network will lay the groundwork for future 2-Dimensional and 3-Dimensional devices for simultaneous protection from intrusion. Off the shelf copper spheres with diameter of 710 ± 11microns were found through nano-indentation measurements to have elastic modulus of 106GPa, and compressive yield strength of 729MPa, these spheres were prepared for test in a 1-Dimensional array device. The arrays response to mechanical perturbations modeled by Hertz contact mechanics can be monitored by simultaneous electrical measurements across the multiple metal-insulator-metal …
Numerical Analysis Of First-Order Acousto-Optic Bragg Diffraction Of Profiled Optical Beams Using Open-Loop Transfer Functions,
2014
University of Dayton
Numerical Analysis Of First-Order Acousto-Optic Bragg Diffraction Of Profiled Optical Beams Using Open-Loop Transfer Functions, Monish Ranjan Chatterjee, Fares S. Almehmadi
Electrical and Computer Engineering Faculty Publications
In standard acousto-optic Bragg analysis, the incident light and sound beams are assumed to be uniform plane waves (with constant profiles) leading to the results based on standard weak interaction theory. As a follow-up to earlier work dealing with nonuniform incident optical beams, we revisit the problem of Bragg diffraction under nonuniform profiles, and include Gaussian, third-order Hermite–Gaussian, and zeroth-order Bessel profiles in our investigation, along with a few others. The first-order diffracted beam is examined (using a transfer function formalism based on angular spectra) under several parametric limits [such as the Klein–Cook parameter Q, the effective profile width, and …
Investigation Of Degradation Effects Due To Gate Stress In Gan-On-Si High Electron Mobility Transistors Through Analysis Of Low Frequency Noise,
2014
California Polytechnic State University, San Luis Obispo
Investigation Of Degradation Effects Due To Gate Stress In Gan-On-Si High Electron Mobility Transistors Through Analysis Of Low Frequency Noise, Michael Curtis Meyer Masuda
Master's Theses
Gallium Nitride (GaN) high electron mobility transistors (HEMT) have superior performance characteristics compared to Silicon (Si) and Gallium Arsenide (GaAs) based transistors. GaN is a wide bandgap semiconductor which allows it to operate at higher breakdown voltages and power. Unlike traditional semiconductor devices, the GaN HEMT channel region is undoped and relies on the piezoelectric effect created at the GaN and Aluminum Gallium Nitride (AlGaN) heterojunction to create a conduction channel in the form of a quantum well known as the two dimensional electron gas (2DEG). Because the GaN HEMTs are undoped, these devices have higher electron mobility crucial for …
