Engineering Commons^™

Test 2051: New Holland Ts6.125, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Test 2050: New Holland Ts6.140, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

An Adaptive Utility Interactive Photovoltaic System Based On A Flexible Switch Matrix To Optimize Performance In Real-Time, Mahmoud Alahmad, Mohamed Amer Chaaban, Siu Kit Lau, Jonathan Shi, Jill Neal

Durham School of Architectural Engineering and Construction: Faculty Publications

Reconfigurable architectures are of great interest to system designers to improve the system’s operation and efficiency. In this paper, we propose an adaptive utility interactive photovoltaic (PV) system based on a novel Flexible Switch array Matrix topology. This proposed system maximizes the generated power in real-time in response to operational conditions such as shading, soiling, mismatches, and module failure among others. The proposed system is a compromise in the utilization of power conditioning equipment to maximize energy capture and system efficiency. Simulation results demonstrate an average 13% improvement in efficiency when compared with the central inverter topology performance. A prototype …

Effects Of Roof Pitch On Air Flow And Heating Load Of Sealed And Vented Attics For Gable-Roof Residential Buildings, Shimin Wang, Zhigang Shen

Durham School of Architectural Engineering and Construction: Faculty Publications

Pitch value is an important consideration in residential gable roof design and construction. However, how roof pitch, coupled with air flows in attic space, affects the energy performance of building attics has been barely investigated. In this paper, a 2D unsteady computational fluid dynamics (CFD) model is employed to investigate the effects of roof pitch on air flow and heating load of both sealed and vented attics for gable-roof residential buildings. The simulation results show that air flow in the sealed attics is steady and asymmetric, while that in the vented attics is a combination of an essentially symmetric base …

Real-Time Stereo Matching On Cuda Using An Iterative Refinement Method For Adaptive Support-Weight Correspondences, Jedrzej Kowalczuk, Eric T. Psota, Lance C. Pérez

Department of Electrical and Computer Engineering: Faculty Publications

High-quality real-time stereo matching has the potential to enable various computer vision applications including semi-automated robotic surgery, tele-immersion, and three-dimensional video surveillance. A novel real-time stereo matching method is presented that uses a two-pass approximation of adaptive support-weight aggregation, and a low-complexity iterative disparity refinement technique. Through an evaluation of computationally efficient approaches to adaptive support weight cost aggregation, it is shown that the two-pass method produces an accurate approximation of the support weights while greatly reducing the complexity of aggregation. The refinement technique, constructed using a probabilistic framework, incorporates an additive term into matching cost minimization and facilitates iterative …

Oscillation Mitigation For Sliding-Mode Observers In Sensorless Control Of Ipmsms, Yue Zhao, Wei Qiao, Long Wu

Department of Electrical and Computer Engineering: Faculty Publications

Back electromagnetic force (EMF)-based methods are commonly used for sensorless control of interior permanent magnet synchronous machines (IPMSMs) in medium and high speed range. The feature of high robustness to system structure and parameter uncertainties makes the sliding-mode observer (SMO) a promising candidate for rotor position estimation. In a practical drive system, because of physical limitations, e.g., sampling frequency and computational resource, it is challenging to obtain a perfect sinusoidal waveform for the back EMF by a SMO, especially in high speed range. As a result, the rotor position obtained from the estimated back EMF by using the traditional inverse …

Optimal Advance Detector Location For Green Termination Systems On High-Speed Isolated Rural Intersections, Lili Du, Anuj Sharma, Srinivas Peeta

Department of Civil and Environmental Engineering: Faculty Publications

This study seeks to identify the optimal location of an advance point traffic detector (APTD) to support green termination algorithms for enhanced dilemma zone protection systems at high-speed isolated signalized rural intersections. This is done by developing a nonlinear optimization model with the objective to maximize the opportunities to predict empty dilemma zones during a look-ahead time period subject to the prediction accuracy which is manifested through prediction efficiency and safety constraints in the model. The distance of the APTD from the stop bar of the intersection represents the decision variable. The Golden-Section line search algorithm combined with numerical integration …

Methane And Carbon Dioxide Production From Simulated Anaerobic Degradation Of Cattle Carcasses, Qi Yuan, Samuel Saunders, Shannon L. Bartelt-Hunt

Department of Civil and Environmental Engineering: Faculty Publications

Approximately 2.2 million cattle carcasses require disposal annually in the United States. Land burial is a convenient disposal method that has been widely used in animal production for disposal of both daily mortalities as well as during catastrophic mortality events. To date, greenhouse gas production after mortality burial has not been quantified, and this study represents the first attempt to quantify greenhouse gas emissions from land burial of animal carcasses. In this study, anaerobic decomposition of both homogenized and unhomogenized cattle carcass material was investigated using bench-scale reactors. Maximum yields of methane and carbon dioxide were 0.33 and 0.09 m …

Effects Of Inclusion Shapes Within Rigid Porous Materials On Acoustic Performance, Hyun Hong, Siu-Kit Lau

Durham School of Architectural Engineering and Construction: Faculty Publications

The present study investigates the influence of various shapes of inclusions having same volume embedded in a porous rigid material. Previous studies showed improvement of the broadband sound absorption with particular shapes of inclusions. However, different volumes of the inclusions have been considered; therefore, the bulk densities are not the same for comparison. The present study extends the investigations of inclusions in porous materials with same volume (or bulk density) to eliminate the influence by the change of bulk density. The effects of shape will be discussed. Finite element modeling will be used for this study. Total four different shapes: …

Impacts Of Ventilation Ratio And Vent Balance On Cooling Load And Air Flow Of Naturally Ventilated Attics, Shimin Wang, Zhigang Shen

Durham School of Architectural Engineering and Construction: Faculty Publications

The impacts of ventilation ratio and vent balance on cooling load and air flow of naturally ventilated attics are studied in this paper using an unsteady computational fluid dynamics (CFD) model. Buoyancy-driven turbulent ventilations in attics of gable-roof residential buildings are simulated for typical summer conditions. Ventilation ratios from 1/400 to 1/25 combined with both balanced and unbalanced vent configurations are investigated. The modeling results show that the air flows in the attics are steady and exhibit a general streamline pattern that is qualitatively insensitive to the variations in ventilation ratio and vent configuration. The predicted temperature fields are characterized …

The Impact Of Roof Pitch And Ceiling Insulation On Cooling Load Of Naturally-Ventilated Attics, Shimin Wang, Zhigang Shen, Linxia Gu

Durham School of Architectural Engineering and Construction: Faculty Publications

A 2D unsteady computational fluid dynamics (CFD) model is employed to simulate buoyancy-driven turbulent ventilation in attics with different pitch values and ceiling insulation levels under summer conditions. The impacts of roof pitch and ceiling insulation on the cooling load of gable-roof residential buildings are investigated based on the simulation of turbulent air flow and natural convection heat transfer in attic spaces with roof pitches from 3/12 to 18/12 combined with ceiling insulation levels from R-1.2 to R-40. The modeling results show that the air flows in the attics are steady and exhibit a general streamline pattern that is qualitatively …

Development And Evaluation Of A Simplified Modeling Approach For Hydraulic Systems, Yuebin Yu, Vivian Loftness, Daihong Yu, Yan Lu, Volker Hartkopf

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper presents how a hydraulic system can be properly modeled for hydraulic balancing, knowledge of flow distribution, coupled simulation, and evaluation of control, etc. It focuses on water-based heating and cooling systems, which generally have high energy efficiency in design but could perform poorly in reality due to the undersensing condition and strong thermal-hydraulic coupling. The study introduces the motivation, presents the simplified modeling methodology, and illustrates the model and simulating structure. A preliminary evaluation of the method is conducted with two simple simulations. The proposed “node-branch-state” modeling approach could be easily modified, expanded and integrated into a detailed …

Sensing Through The Continent: Towards Monitoring Migratory Birds Using Cellular Sensor Networks, David Anthony, William P. Bennett, Mehmet C. Vuran, Matthew B. Dwyer, Sebastian Elbaum, Anne Lacy, Mike Engels, Walter Wehtje

School of Computing: Conference and Workshop Papers

This paper presents CraneTracker, a novel sensor platform for monitoring migratory birds. The platform is designed to monitor Whooping Cranes, an endangered species that conducts an annual migration of 4, 000 km between southern Texas and north-central Canada. CraneTracker includes a rich set of sensors, a multi-modal radio, and power control circuitry for sustainable, continental-scale information delivery during migration. The need for large-scale connectivity motivates the use of cellular technology in low-cost sensor platforms augmented by a low-power transceiver for ad-hoc connectivity. This platform leads to a new class of cellular sensor networks (CSNs) for time-critical and mobile sensing applications. …

Tuning Of The Size And The Lattice Parameter Of Ion-Beam Synthesized Pb Nanoparticles Embedded In Si, Huan Wang, J. Cuppens, E. Biermans, S. Bals, Lucia Fernandez-Ballester, K. O. Kvashnina, W. Bras, M. J. Van Bael, K. Temst, A. Vantomme

Department of Engineering Mechanics: Faculty Publications

The size and lattice constant evolution of Pb nanoparticles (NPs) synthesized by high fluence implantation in crystalline Si have been studied with a variety of experimental techniques. Results obtained from small-angle x-ray scattering showed that the Pb NPs grow with increasing implantation fluence and annealing duration. The theory of NP growth kinetics can be applied to qualitatively explain the size evolution of the Pb NPs during the implantation and annealing processes. Moreover, the lattice constant of the Pb NPs was evaluated by conventional x-ray diffraction. The lattice dilatation was observed to decrease with increasing size of the Pb NPs. Such …

Experimental Testing And Finite-Element Modeling To Evaluate The Effects Of Aggregate Angularity On Bituminous Mixture Performance, Leonardo T. Souza, Yong-Rak Kim, Flavio V. Souza, Leandro S. Castro

Department of Engineering Mechanics: Faculty Publications

This study evaluates the effects of aggregate angularity in bituminous mixtures. Previous studies have predominantly focused on the effects of aggregate angularity on the resistance to permanent deformation, while little work has investigated the role of aggregate angularity related to mixture volumetrics and fatigue fracture performance. To investigate the effect of aggregate angularity on mixture performance and characteristics, five mixes with different combinations of coarse and fine aggregate angularity are evaluated by performing the uniaxial static creep test and the indirect tensile fracture energy test. The asphalt pavement analyzer test is also performed with five-year field project mixtures. Fracture energy …

Real-Time Optimal Participation Of Wind Power In An Electricity Market, Ting Dai, Wei Qiao, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

While integrating wind power into the electricity market can reduce the operational and fuel costs of the power system, it also increases the imbalance cost and the need for reserve. Due to this contradictory, there is a need for planning the amount of wind power in the power system. This paper proposes a model to determine the real-time optimal participation of wind power in an electricity market. This model assumes that the system operator will regulate the participation level of the wind power due to the increasing cost of reserve. Case studies are presented to demonstrate the use of the …

Imbalance Fault Detection Of Direct-Drive Wind Turbines Using Generator Current Signals, Xiang Gong, Wei Qiao

Department of Electrical and Computer Engineering: Faculty Publications

Imbalance faults constitute a significant portion of all faults in wind turbine generators (WTGs). WTG imbalance fault detection using generator current measurements has advantages over traditional vibration-based methods in terms of cost, implementation, and system reliability. However, there are challenges in using current signals for imbalance fault detection due to low signal-to-noise ratio of the useful information in current signals and non-stationary characteristic frequencies of imbalance faults. This paper proposes a method of using generator stator currents for imbalance fault detection of direct-drive WTGs. In the proposed method, the variable shaft rotating frequency of a WTG is estimated from one …

Power Semiconductor Devices, Jerry Hudgins, Rik W. De Doncker

Department of Electrical and Computer Engineering: Faculty Publications

Historically, Power Semiconductor devices have been divided into three broad categories: diodes, transistors, and thyristors. Although modern devices can be classified in this way, there is an increasing overlap in device design and function. Also semiconductors, such as silicon carbide (SiC), gallium nitride (GaN), and other materials, as well as novel device designs have increased the suitability and broadened the applications of semiconductor switches in megawatt (MW) power conversion circuits and systems.

Modern Transistors

Transistors include the traditional power bipolar (nonsilicon materials being considered for the future), power metal-oxide-semiconductor field-effect transistors (MOSFETs), and hybrid devices that have some aspect of …

A Series-Connected Self-Reconfigurable Multicell Battery Capable Of Safe And Effective Charging/Discharging And Balancing Operations, Taesic Kim, Wei Qiao, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

Bidirectional DC/DC converters are commonly used for charging and discharging multicell batteries under various modes, such as Pulsed Current (PC), Constant Current (CC), and Constant Current Constant Voltage (CCCV). The charge and discharge are usually terminated by the converters when battery voltages reach some threshold values. However, cell state imbalance is commonly present in traditional multicell batteries, which reduces the available capacities of the batteries in certain charge/discharge cycles and shortens the life cycles of the batteries. To solve this problem, this paper proposes a series-connected, self-reconfigurable, multicell battery with a bidirectional DC/DC converter capable of safe and effective charging, …

Analysis Of Π-Phase-Shifted Fiber Bragg Gratings For Ultrasonic Detection, Tongqing Liu, Ming Han

Department of Electrical and Computer Engineering: Faculty Publications

Using numerical simulations, we investigated the responses of the π-phase-shifted fiber Bragg gratings (πFBGs) impinged by pressure ultrasonic waves. The effect of the grating length, grating refractive index modification depth, and ultrasonic frequency on the wavelength sensitivity and intensity sensitivity of the πFBG ultrasonic sensor for ultrasonic waves of different wavelengths was analyzed. The directivity of a πFBG sensor was also studied. Our analysis revealed several unique πFBG response characteristics and will be useful in the design and optimization of fiber-optic ultrasonic sensors that use a πFBG as the sensing element.

Optical Properties Of Cobalt Slanted Columnar Thin Films Passivated By Atomic Layer Deposition, Daniel Schmidt, Eva Schubert, Mathias Schubert

Department of Electrical and Computer Engineering: Faculty Publications

Optical properties of passivated metal slanted columnar thin films from cobalt within the visible spectral region are reported. Glancing angle deposition is utilized to grow slanted nano-columns which have been conformally coated with Al₂O₃ by a subsequent atomic layer deposition process. A generalized anisotropic Bruggeman effective medium approximation has been employed to analyze spectroscopic generalized ellipsometry data. The modified homogenization approach allows for determination of biaxial (monoclinic) optical and structural properties as well as fractions of three film constituents. The conformal alumina passivation layer preserves the pristine metal character of the nano-structures and prevents oxidation and aging …

Position Extraction From A Discrete Sliding-Mode Observer For Sensorless Control Of Ipmsms, Yue Zhao, Wei Qiao, Long Wu

Department of Electrical and Computer Engineering: Faculty Publications

Sliding-mode observers (SMOs) offer a promising solution for sensorless control of interior permanent magnet synchronous machines (IPMSMs) due to their excellent robustness to system structure and parameter uncertainty. However, in practical applications, it is challenging for an SMO to achieve a perfect estimation for the back electromagnetic force (EMF) using a finite or relatively lower sampling frequency, especially for high-speed applications. Phase shift, magnitude variation, and heavy noise in the estimated back EMF will cause unexpected errors in rotor position extraction. Thus, advanced rotor position extraction methods are needed to obtain position information from the estimated back EMF. This paper …

Compensation Algorithms For Sliding Mode Observers In Sensorless Control Of Ipmsms, Yue Zhao, Wei Qiao, Long Wu

Department of Electrical and Computer Engineering: Faculty Publications

Electromechanical sensors are commonly used to obtain rotor position/speed for high-performance control of interior permanent magnet synchronous machines (IPMSMs) in vehicle systems. However, the use of these sensors increases the cost, size, weight, wiring complexity and reduces the mechanical robustness of IPMSM drive systems. These issues, together with some practical requirements, e.g., wide speed range, extreme environment temperature, and adverse loading conditions, make a sensorless control scheme desirable. This paper proposes an extended back electromotive force (EMF)-based sliding mode rotor position observer for sensorless vector control of IPMSMs. Based on filter characteristics, a robust compensation algorithm is developed to improve …

A Low-Cost, Reliable, High-Throughput System For Rodent Behavioral Phenotyping In A Home Cage Environment, Steven A. Parkison, Jay D. Carlson, Tammy R. Chaudoin, Traci A. Hoke, A. Katrin Schenk, Evan H. Goulding, Lance C. Pérez, Stephen J. Bonasera

Department of Electrical and Computer Engineering: Faculty Publications

Inexpensive, high-throughput, low maintenance systems for precise temporal and spatial measurement of mouse home cage behavior (including movement, feeding, and drinking) are required to evaluate products from large scale pharmaceutical design and genetic lesion programs. These measurements are also required to interpret results from more focused behavioral assays. We describe the design and validation of a highly-scalable, reliable mouse home cage behavioral monitoring system modeled on a previously described, one-ofa- kind system [1]. Mouse position was determined by solving static equilibrium equations describing the force and torques acting on the system strain gauges; feeding events were detected by a photobeam …

Nonlinear Plasmonic Cloaks To Realize Giant All-Optical Scattering Switching, Christos Argyropoulos, Pai-Yen Chen, Francesco Monticone, Giuseppe D'Aguanno, Andrea Alu

Department of Electrical and Computer Engineering: Faculty Publications

Here we extend the reach of Fano resonant coupling by combining this concept with cloaking and plasmonic resonances in a single nonlinear nanoparticle, in order to realize giant all-optical scattering nanoswitches controlled by moderate pumping intensities. We show that a core-shell nonlinear plasmonic particle may be designed to abruptly switch from being completely cloaked to being strongly resonant, with up to a 40 dB cross-sectional difference. Self-tunable optical cloaks and resonant scatterers are envisioned for use as efficient all-optical switches and nanomemories.

Boosting Optical Nonlinearities In E-Near-Zero Plasmonic Channels, Christos Argyropoulos, Pai-Yen Chen, Giuseppe D'Aguanno, Nadar Engheta, Andrea Alu

Department of Electrical and Computer Engineering: Faculty Publications

The anomalous transmission properties of zero-permittivity ultranarrow channels are used to boost Kerr nonlinearities and achieve switching and bistable response for moderate optical intensities. Strong field enhancement, uniform all along the channel, is a typical feature of ε-near-zero supercoupling and is shown to be particularly suited to enhance nonlinear effects. This is obtained by designing narrow apertures at cutoff in a plasmonic screen. We show that this nonlinear mechanism can significantly outperform nonlinearities in traditional Fabry-P´erot resonant gratings.

Broadband Brewster Transmission Through 2d Metallic Gratings, Khai Q. Le, Christos Argyropoulos, Nadia Mattiucci, Giuseppe D'Aguanno, Mark J. Bloemer, Andrea Alu

Department of Electrical and Computer Engineering: Faculty Publications

Recently, we have introduced a mechanism to achieve ultrabroadband light funnelling and total transmission through 1D narrow metallic gratings at a specific incidence angle, the so-called plasmonic Brewster angle. This phenomenon is based on impedance matching between the guided modes supported by ultranarrow linear slits and transverse-magnetic waves at oblique incidence. In this paper, we demonstrate that such phenomenon, representing the equivalent of Brewster transmission for plasmonic screens, can also occur in 2D metallic gratings of various structural forms and shapes, and that it may be made insensitive to the azimuthal, or polarization, angle u. This finding may have relevant …

Laser Induced Breakdown Spectroscopy Having Enhanced Signal-To-Noise Ratio, Dennis R. Alexander, Troy Anderson, John C. Bruce Iii

Department of Electrical and Computer Engineering: Faculty Publications

A material can be analyzed using short pulses by applying a first pulse and a second pulse to the material in which the second pulse is delayed relative to the first pulse. The first and second pulses are directed toward a material along collinear paths, and the material is ablated using the first pulse to cause particles to be emitted from the surface of the material. The emitted particles are atomized and/or ionized using the second pulse, and the radiation from the atomized and/or ionized particles is analyzed.

Empirical Correction For Spectroscopic Ellipsometric Measurements Of Rough Or Textured Surfaces, Craig M. Herzinger, Blaine D. Johs, Mathias M. Schubert, Tino Hofmann

Department of Electrical and Computer Engineering: Faculty Publications

A method of applying spectroscopic ellipsometry to arrive at accurate values of optical and physical properties for thin films on samples having rough or textured surfaces.

An Adaptive Algorithm For Corrupted Images, Deborah D. Duran-Herrmann, Qilin Qi, Yaoqing Lamar Yang

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

Noise is ever-present in communication channels and can produce devastating degradation to the images at the receiver end. In this paper, a novel approach to detecting different types of noise models in corrupted images is presented. Basically, it is a two-step process that has the ability to handle real-time applications due to its computational simplicity. The proposed algorithm handles error correction more efficiently in the second stage of processing, given a means to detect the type of noise present in the first stage. This algorithm will be verified and tested against existing methods on different noise models. Preliminary results show …