Engineering Commons^™

Research On Weather Conditions And Their Relationship To Crashes, Mark R. Anderson, Aemal Khattak, Muhammad Umer Farooq, John Cecava, Curtis L. Walker

Nebraska Department of Transportation: Research Reports

The objectives of the research were to conduct a seasonal investigation of when winter weather conditions are a factor in crashes reported in Nebraska, to perform statistical analyses on Nebraska crash and meteorological data and identify weather conditions causing the significant safety concerns, and to investigate whether knowing the snowfall amount and/or storm intensity/severity could be a precursor to the number and severity of crashes.

Nebraska Department of Transportation (NDOT) crash data were combined with meteorological data on winter weather season basis, reported road surface condition at crash time, and reported weather conditions at crash time. Overall, the key finding …

Nebraska Rail Crossing Safety Research, Aemal Khattak, Yashu Kang, Huiyuan Liu

Nebraska Department of Transportation: Research Reports

The research objectives of this project were to update Nebraska Department of Transportation (NDOT) 1999 Nebraska Accident Prediction Model for Highway-Rail Grade Crossings (HRGCs) and to develop guidelines using Lancaster County Nebraska HRGCs for improving safety at urban gated HRGCs that are not designated quiet zones but are in the vicinity of quiet zone crossings.

FRA crash and HRGC inventory data were utilized for estimation of the new model after inventory information on 742 HRGCs was updated. HRGC crashes for 2008-2018 period were used for model estimation while 2019 HRGC crashes were used for model prediction validation. After consideration of …

To Automate Detecting, Quantifying And Mapping Of Delamination Via Arial Thermography, Ziqi Shen, Chongsheng Cheng, Ri Na, Zhexiong Shang

Nebraska Department of Transportation: Research Reports

The goal of this project is to develop a UAV-based Arial thermographic method to detect and map the delamination on concrete bridge decks. Several image processing methods such as level-set and machine-learning were developed in this project. The developed method is high-efficient and low-cost and requires no-traffic-closure during the surveying process. The coring outcomes from four different concrete bride decks validated the performance of this developed method. The coring results suggested that this method outperformed several existing methods in detecting delamination in concrete bridge decks in terms of efficiency, accuracy, cost, and safety.

High-Mast Tower Foundation, Chungwook Sim, Chung R. Song, Brandon Kreiling, Jay Puckett

Nebraska Department of Transportation: Research Reports

High-Mast Tower (HMT) foundations have been traditionally designed and constructed using cast-in-place foundation with anchor bolts that are used to secure the tower to the foundation. This type of design requires a base plate that is welded to the tower shaft. The Nebraska Department of Transportation (NDOT) has recently experienced issues with stresses that this type of design presents at the anchor bolt/foundation or base plate/tower shaft interface. This issue in worst cases may lead to a premature failure due to high-cycle fatigue as one of the towers at Milford, Nebraska that fell down during a winter snow storm event …

Possibilities And Challenges Of Radio Frequency Energy Harvesting In Dar Es Salaam, Tanzania, Fredrick Isingo

Tanzania Journal of Engineering and Technology (TJET)

This paper presents investigation on the possibilities and challenges of harvesting ambient Radio Frequency Energy (RFE) at Dar es Salaam region in Tanzania. The Radio Frequency (RF) signals were measured using a Rohde and Schwarz FSC 3 spectrum analyzer observing available frequencies with their respective power. Among several RF signals received, the most powerful signals observed were; 800 MHz, 950 MHz, 2100 MHz and 2400 MHz, having average signal strengths of about-30.29 dBm,-35.94 dBm,-42.90 dBm and-30.42 dBm respectively. The power possessed within these frequencies were suitable to be harvested due to their signal strengths, an overall power average of-34.89dBm was …

Enhancing Bim Implementation In The Ethiopian Public Construction Sector: An Empirical Study, Solomon Belay, James D. Goedert, Asregedew Woldesenbet, Saeed Rokooei3

Durham School of Architectural Engineering and Construction: Faculty Publications

Recently, the popularity of BIM has grown rapidly in the public construction sector. However, only a few studies so far have been seeking to address the BIM adoption benefits and barriers in developmental public projects across the low-income countries. Thus, the study aims to investigate the benefits and barriers of BIM adoption in the context of the Ethiopian infrastructure market. To achieve the objectives, a comprehensive systematic literature review was conducted to identify BIM adoption benefits and barriers in developing countries. Then, a structured questionnaire survey was conducted to collect data from various professionals working in organizations including client, consultant, …

Preparation And Characterization Of Reactive Composites Combining Boron With Mixed Oxides, Purvam Mehulkumar Gandhi

Theses

Thirteen liquids have been explored as Process Control Agents (PCAs) for high-energy mechanical milling of two metal oxide powders, CuO and Bi₂O₃, with the practical purpose to reduce the sizes of powder particles and refine their crystal structure. Multiple liquid properties have been considered to analyze their effect on evolution of both particle and crystallite sizes during milling for each oxide. Experimental data were analyzed using the δ-AICc (Akaike Information criterion) correlation function applied to linear relations between liquid properties and powder characteristics. Multiple linear correlation models were ranked based on the highest log-likelihood and the …

Treated Hfo2 Based Rram Devices With Ru, Tan, Tin As Top Electrode For In-Memory Computing Hardware, Yuvraj Dineshkumar Patel

Theses

The scalability and power efficiency of the conventional CMOS technology is steadily coming to a halt due to increasing problems and challenges in fabrication technology. Many non-volatile memory devices have emerged recently to meet the scaling challenges. Memory devices such as RRAMs or ReRAM (Resistive Random-Access Memory) have proved to be a promising candidate for analog in memory computing applications related to inference and learning in artificial intelligence. A RRAM cell has a MIM (Metal insulator metal) structure that exhibits reversible resistive switching on application of positive or negative voltage. But detailed studies on the power consumption, repeatability and retention …

Cycloidal-Drive Joint Design For Wearable Exoskeletons, Abhi J. Rawal

Theses

This thesis's scope was to construct a highly back drivable and compact joint design that can be used for wearable exoskeletons specifically designed to assist with rehabilitation. A compact cycloidal gear transmission was designed to satisfy the compactness requirement while ensuring the minimum torque is required for backdriving the mechanism. The joint was designed based on the compact cycloidal drive specifications, and the backdrivability test was performed to measure the minimum torque required (1.20 Nm) to backdrive. The joint design incorporates various important features such as rotation lock feature to prevent hyperextension, a housing design that offers the benefit of …

User-Centred Scalable Big Data Visualizer For Power Consumption Data In The Electrical Secondary Distribution Network, Ellen Kalinga

Tanzania Journal of Engineering and Technology (TJET)

Establishment of Smart Grids for electrical power has been practised worldwide for the purpose of bringing reliability, security, and efficient management of electrical power networks for enhancing quality service to the society. Apart from the potential aim, smart grid has been a challenge to developing countries, including Tanzania from cost and technology point of view. Due to the use of many smart equipment involved in smart grids like Advanced Metering Infrastructure (AMI) equipped with smart meters and sensors, handling and managing big data has been a challenge. Among the challenges is the issue of visualizing the Big Data due to …

A Review Of Different Aspects Of Applying Asphalt And Bituminous Mixes Under A Railway Track, Kazem Jadidi, Morteza Esmaeili, Mehdi Kalantari, Moses Karakouzian

Civil and Environmental Engineering and Construction Faculty Research

Asphalt is a common material that is used extensively for roadways. Furthermore, bituminous mixes have been used in railways, both as asphalt and as mortar. Different agencies and research institutes have investigated and suggested various applications. These studies indicate the benefits of bituminous material under railways, such as improving a substructure’s stiffness and bearing capacity; enhancing its dynamic characteristics and response, especially under high-speed train loads; waterproofing the subgrade; protecting the top layers against fine contamination. These potential applications can improve the overall track structure performance and lead to minimizing settlement under heavy loads. They can also guarantee an appropriate …

A Review Of Different Aspects Of Applying Asphalt And Bituminous Mixes Under A Railway Track, Kazem Jadidi, Morteza Esmaeili, Mehdi Kalantari, Mehdi Khalili

Civil and Environmental Engineering and Construction Faculty Research

Asphalt is a common material that is used extensively for roadways. Furthermore, bituminous mixes have been used in railways, both as asphalt and as mortar. Different agencies and research institutes have investigated and suggested various applications. These studies indicate the benefits of bituminous material under railways, such as improving a substructure’s stiffness and bearing capacity; enhancing its dynamic characteristics and response, especially under high-speed train loads; waterproofing the subgrade; protecting the top layers against fine contamination. These potential applications can improve the overall track structure performance and lead to minimizing settlement under heavy loads. They can also guarantee an appropriate …

Neural Networks On An Fpga And The Exploration Of Hardware Friendly Activation Functions, Jiong Si, Sarah L. Harris, Evangelos Yfantis

Electrical & Computer Engineering Faculty Research

This paper describes our implementation of several neural networks built on a field programmable gate array (FPGA) and used to recognize a handwritten digit dataset—the Modified National Institute of Standards and Technology (MNIST) database. We also propose a novel hardware-friendly activation function called the dynamic Rectifid Linear Unit (ReLU)—D-ReLU function that achieves higher performance than traditional activation functions at no cost to accuracy. We built a 2-layer online training multilayer perceptron (MLP) neural network on an FPGA with varying data width. Reducing the data width from 8 to 4 bits only reduces prediction accuracy by 11%, but the FPGA area …

Deconvolution Of Mono-Energetic And Multi-Lines Gamma-Ray Spectra Obtained With Nai(Tl) Scintillation Detectors Using Direct Matrix Inversion Method, Mwingereza John Kumwenda Dr

Tanzania Journal of Engineering and Technology (TJET)

Performance of a NaI(Tl) scintillation detector based on the gamma-ray spectroscopy system is not satisfactory in retaining its original peak (which is delta like function) of various gamma ray spectrum. The method of achieving precise peak for the various gamma ray was conducted by converting the observed pulse-height distribution of the NaI(Tl) detector to a true photon spectrum. This method is obtained experimentally with the help of an inverse matrix deconvolution method. The method is based on response matrix generated by the Monte Carlo simulation based on Geant4 package of mono-energy gamma-ray photon ranging from 0.050 to 2.04 MeV in …

Incident Duration Time Prediction Using A Supervised Topic Modeling Method, Jihyun Park

Theses

Precisely predicting the duration time of an incident is one of the most prominent components to implement proactive management strategies for traffic congestions caused by an incident. This thesis presents a novel method to predict incident duration time in a timely manner by using an emerging supervised topic modeling method. Based on Natural Language Processing (NLP) techniques, this thesis performs semantic text analyses with text-based incident dataset to train the model. The model is trained with actual 1,466 incident records collected by Korea Expressway Corporation from 2016-2019 by applying a Labeled Latent Dirichlet Allocation(L-LDA) approach. For the training, this thesis …

Human Activity Recognition Using Wearable Sensors: A Deep Learning Approach, Jialun Xue

Theses

In the past decades, Human Activity Recognition (HAR) grabbed considerable research attentions from a wide range of pattern recognition and human–computer interaction researchers due to its prominent applications such as smart home health care. The wealth of information requires efficient classification and analysis methods. Deep learning represents a promising technique for large-scale data analytics. There are various ways of using different sensors for human activity recognition in a smartly controlled environment. Among them, physical human activity recognition through wearable sensors provides valuable information about an individual’s degree of functional ability and lifestyle. There is abundant research that works upon real …

Comparative Analysis Of Multiplicative And Additive Noise Based Automated Regularizations In Non-Linear Diffusion Image Reconstruction, Chiza Christophe

Tanzania Journal of Engineering and Technology (TJET)

Multiplicative and additive noises are often introduced in image signals during the image acquisition process and result into degradation of image features. The work done by Perona and Malik in 1990 and its modified versions revolutionized the way through which noises or speckles are removed. The Perona-Malik model requires tuning of the regularization parameter to control and prevent staircase artifacts in restored images. The current manual tuning is a challenging and time consuming practice when a long queue of images is registered for processing. Attempt to automate the regularization parameter appeared in Perona-Malik model with self-adjusting shape-defining constant. Although both …

Direct Predictive Speed Control Of Salient Pmsm Drives In Constant Torque And Constant Power Regimes For Electric Vehicles Applications, Francis Mwasilu

Tanzania Journal of Engineering and Technology (TJET)

A direct speed control of salient permanent magnet synchronous motor (PMSM) drives in constant torque and constant power regimes for electric vehicles applications is presented. The proposed speed control scheme is derived from model predictive control approach where both rotor speed and stator current are formulated in a single objective function that is periodically computed to attain the PMSM drive optimum switching states. The dynamic model of the PMSM intrinsically encompasses the unknown disturbance, which should be rejected for high-performance speed control especially in transient conditions. Consequently, the extended modified augmented state Kalman filter (ASKF) is incorporated in the proposed …

Assessment Of The Performance Of Grinding Circuit For Buzwagi Gold Mine, Alphonce Wikedzi

Tanzania Journal of Engineering and Technology (TJET)

It had been reported by the management of Buzwagi Gold Mine (BGM) that grinding circuit was designed to produce final product size of 125 μm, which had not been achieved for a long period of time under both, low to normal (i.e. 450-600 t/h) and high (i.e. > 650 t/h) throughputs. Also, the performance behaviour of the circuit had not been reviewed after long time of operation. Hence, an evaluation study was conducted in order to recommend improvement in mine operations. The study was realized through three circuit survey campaigns and laboratory experimentations. From the surveys, size distributions and solids contents …

Effects Of Calcination Temperature Of Naturally Occurring Absorbents On Drinking Water Defluoridation, Brenda Mndolwa

Tanzania Journal of Engineering and Technology (TJET)

Currently, in Tanzania, fluoride removal from drinking water is treated mostly using the bone char method. The method has poor acceptability in some religious communities and also causes water quality deterioration in taste and odour if the bones are not properly prepared. The use of local natural adsorbents as an alternative is feasible with limitations of high levels of other impurities in treated water. Locally available gypsum, magnesite and bauxite were converted to adsorbents through calcination. The study was conducted to determine the removal efficiency, best calcination temperature and composite ratio of the three adsorbents for the removal of fluoride …

Fermentability Of Concentrated Sulfuric Acid Hydrolyzates From Aspenwood And Pinewood, Kando Janga

Tanzania Journal of Engineering and Technology (TJET)

The fermentability of hydrolyzates derived from two-stage concentrated sulfuric acid hydrolysis of Trembling aspen (Populus tremula) and Scots pine (Pinus sylvestris) were investigated. Three types of hydrolyzates were produced at mild, moderate and high decrystallization severity conditions. Portions of each of the original hydrolyzates were concentrated by vacuum evaporation to increase the sugar fraction to simulate industrial applications. Both sets of hydrolyzates were fermented anaerobically using Saccharomyces cerevisiae ATCC 96581. After 23 hours of fermentation, complete glucose consumption was observed for all the original hydrolyzates, with no signs of inhibition. The ethanol yields from these hydrolyzates ranged from 68% to …

Analysis Of Performance Characteristics Predicted From Several Experimental Data And Conversion Methods For Pumps As Turbine Application Using Statistical Techniques, Ombeni J. Mdee

Tanzania Journal of Engineering and Technology (TJET)

Different performance characteristics have been indicated when running centrifugal pumps in the reverse direction. The water flows from the discharge side of the pump to the suction side to run in the reverse direction and generate the mechanical rotational energy for the micro-hydropower plant. The current study evaluates the extent of variation of performance characteristics predicted by several experimental data from different pump-specific speeds and conversion methods. The performance characteristics discussed include the head, flow rate, efficiency and specific speed. The flow rate and head of a pump operating in pump mode divided with the characteristic of the pump operating …

Potential For Increased Rural Electrification Rate In Sub-Saharan Africa Using Swer Power Distribution Networks, Aviti Thadei Mushi

Tanzania Journal of Engineering and Technology (TJET)

Rural electrification rate (RER) in Africa is still low to date. Several countries in Sub-Saharan Africa have tried to address this problem using conventional single phase two-wire or three-phase three-wire systems, however at large costs due to the nature of dispersed rural load centres, low load demand, and low population density. Another solution of off-grid generation creates associated health problems. Therefore, this paper undertakes a review of a single wire earth return (SWER) network as a RER improvement solution. The paper undertakes intensive literature review to elucidate challenges and solutions to the implementation of SWER technology. Advantages of SWER technology …

Wind Power Integration And Its Impact On Power Quality-A Didactic Approach, Santos Kihwele Dr

Tanzania Journal of Engineering and Technology (TJET)

This paper presents a model of a wind power system integrated with realistic power system, with intention of using it in addressing power quality issues in relations to grid codes during steady-state operation transient-state operation i.e., presence of grid fault events. For that case, a didactic approach of the normal performance of power systems due to the connection of fixed-speed wind turbine with induction generators is used. A study of integrating wind farms will be presented, including the incidence of high inrush current due to switching capacitor banks, out-rush current and voltage sags due to nearby three phase faults. As …

River & Estuary Observation Network: Refinement Of Stage Height Sensor Subsystem For Low Cost And High Reliability, W. D. Kirkey, C. B. Fuller, P. O'Brien, P. J. Kirkey, Ahmed Mahmoud, Andrew Ernest, Javier Guerrero

Civil Engineering Faculty Publications

A system comprised of software and on-site measurements is presented for accurately obtaining water stage data from vented or non-vented submersible pressure sensors installed at autonomous stream gauging stations. The system accounts for pressure sensor offset errors, water density, and local gravitational acceleration to produce a stage height reading which is accurate to either ±0.01 ft (±3 mm) or to the accuracy limit of the sensor, whichever is greater. A 2nd order polynomial expression for determination of water density from temperature and salinity is developed and found to be sufficiently accurate for this purpose. Simulated stage measurements performed in the …

Pillars Of Sustainable Development–Land Capability And Conceptual Project Design, Ian D. Hollingsworth

Journal of Environmental Science and Sustainable Development

Conserving land capability is a pillar of sustainable development strategy. Land units comprising unique combinations of native vegetation, soils, geology, and landforms are used to interpret local environmental processes and land capabilities. An emerging practice is extrapolation modeling of edaphic parameter surfaces in Digital Soil Mapping (DSM) using statistical correlation. Commercial studies of land capability for sustainable development, including a mine closure in a national park, another closure for grazing land restoral, urban stormwater flood mitigation, and wind farm development in plantation forestry, are presented to illustrate applications and review the utility of DSM data. The first case, a mine …

The Beautiful Math Of Everything And You Included, E. Ozie

The Transdisciplinary STEAM+ Journal

This a reflection on how there is beautiful math to everything. An author's interpretation of matrices and mechanics in its relationship to someone's identity.

What Can We Learn About Research Narratives From Professional Storytellers?, Kim Wilkins, Helen Marshall

The Transdisciplinary STEAM+ Journal

This short note on practice reflects on how “research narrative” is a much-used, but misunderstood term. Compelling stories about our research are important: for public-facing communications and for academic tenure confirmation and promotion. They are also important for researchers to gain a clearer sense of their own vision and values in the research process: they are not just a communication skill, they’re a career skill. But often researchers in STEM disciplines do not have the practical skills to write stories. We draw on our own practice as creative writers to share some simple and effective methods to bring arts expertise …

Dual-Adaptive Camouflage For The Hyperstealth Corperation, Keith J. Carlock Mr.

The Transdisciplinary STEAM+ Journal

Dual-Adaptive Camouflage, though still a concept that I've had for 28 years, seems to me, more promising that the bulk and brain power and needed energy supply of a computer-driven network of optical electronic harnesses that would be the basis for any suit that proclaims to render its wearer invisible.

The Assessments Of Internet-Based Technology Use By University Academic Members, Mohammed Alghamdi

BAU Journal - Science and Technology

Social networking applications (SNAs), as technologies that rely on internet infrastructure, are widely used as platforms for user interaction, content creation and social communication. However, in recent years, SNAs have been used in the context of teaching and learning, and this aspect, as well as others, has attracted research attention. Limited research has investigated the motivations and barriers to teaching with SNAs in higher education, and so this study sought to examine the purposes, motivations and barriers associated with SNA use in education among academic members at Albaha University, Saudi Arabia. A quantitative research design involving a sample of academic …