Engineering Commons^™

Impact Of Polymer Binders On The Pull-Out Force Of Macro-Synthetic Fibers In Sprayed Concrete, Klaus Bonin, Christina Neumaier

Shotcrete for Underground Support XIII: New Developments in Rock Engineering, Tunneling, Underground Space and Deep Excavation

The standard test used to characterize the performance of a fiber-reinforced sprayed concrete is the round or square panel test. Steel and macro synthetic fibers with different physical properties are commonly used as reinforcement. The test panel is usually prepared by spraying shotcrete into a steel mold and, after curing, performing a three-point bending test. The difficulty of this kind of preparation is to know where the fibers are located and how many have remained in the sample. There are plenty of factors affecting the fiber distribution, such as the type of shotcrete, wet or dry mix preparation and application …

In Situ Testing Of Early Age Energy Absorption In Sprayed Fiber Reinforced Concrete - Hyea – Test, Michael Kompatscher, Peter Kuhnhenn

Shotcrete for Underground Support XIII: New Developments in Rock Engineering, Tunneling, Underground Space and Deep Excavation

The properties of fibre-reinforced sprayed concrete concerning energy absorption are mainly assessed according the standard of EFNARC, EN14488-5 and ASTM C 1550. Energy absorption will be measured after 28 days up to a deflection of 25 or 40 mm (depending on the applied standard). Fibre-reinforced concrete is often used for rock support and as a first safety layer. When covering the tunnel face with fibre-reinforced sprayed concrete, the concrete will be removed after approx. 6 to 12 hours. Taking into account the situation in modern tunnel headings, the performance of fibre-reinforced sprayed concrete with-in the first hours is essential to …

Optical And Electronic Properties Of Femtosecond Laser-Induced Sulfur-Hyperdoped Silicon N+/P Photodiodes, Ting Zhang, Bohan Liu, Waseem Ahmad, Yaoyu Xuan, Xiangxiao Ying, Zhijun Liu, Zhi David Chen, Shibin Li

Electrical and Computer Engineering Faculty Publications

Impurity-mediated near-infrared (NIR) photoresponse in silicon is of great interest for photovoltaics and photodetectors. In this paper, we have fabricated a series of n⁺/p photodetectors with hyperdoped silicon prepared by ion-implantation and femtosecond pulsed laser. These devices showed a remarkable enhancement on absorption and photoresponse at NIR wavelengths. The device fabricated with implantation dose of 10¹⁴ ions/cm² has exhibited the best performance. The proposed method offers an approach to fabricate low-cost broadband silicon-based photodetectors.

Synthesis Of Non-Uniformly Correlated Partially Coherent Sources Using A Deformable Mirror, Milo W. Hyde Iv, Santasri Bose-Pillai, Ryan A. Wood

Faculty Publications

The near real-time synthesis of a non-uniformly correlated partially coherent source using a low-actuator-count deformable mirror is demonstrated. The statistical optics theory underpinning the synthesis method is reviewed. The experimental results of a non-uniformly correlated source are presented and compared to theoretical predictions. A discussion on how deformable mirror characteristics such as actuator count and pitch affect source generation is also included.

Selfie-Takers Prefer Left Cheeks: Converging Evidence From The (Extended) Selfiecity Database, Lev Manovich, Vera Ferrari, Nicola Bruno

Publications and Research

According to previous reports, selfie takers in widely different cultural contexts prefer poses showing the left cheek more than the right cheek. This posing bias may be interpreted as evidence for a right-hemispheric specialization for the expression of facial emotions. However, earlier studies analyzed selfie poses as categorized by human raters, which raises methodological issues in relation to the distinction between frontal and three-quarter poses. Here, we provide converging evidence by analyzing the (extended) selfiecity database which includes automatic assessments of head rotation and of emotional expression. We confirm a culture- and sex-independent left-cheek bias and report stronger expression of …

Conference Program, Dietmar Mähner, Matthias Beisler, Frank Heimbecher

Shotcrete for Underground Support XIII: New Developments in Rock Engineering, Tunneling, Underground Space and Deep Excavation

No abstract provided.

Media, Institutions And Voting: Perceptions Of Nonmetropolitan Nebraskans: 2017 Nebraska Rural Poll Results, Rebecca J. Vogt, Cheryl A. Burkhart-Kriesel, Randolph L. Cantrell, Bradley Lubben, L. J. Mcelravy, Timothy Meyer

Rural Futures Institute: Publications

Conclusion

Rural Nebraskans most trust information received from local news sources (TV and newspapers) and public sources (PBS and public radio). They least trust information from social networking sites and Internet blogs. Most rural Nebraskans are somewhat or very confident in their ability to recognize news that is made up.

Most rural Nebraskans have confidence in their local institutions (public safety agencies in their community; public schools in their community; and voting and election systems in their county). On the other hand, over one-quarter of rural Nebraskans have very little confidence in the following national institutions: U.S. House of Representatives, …

Wingtip Vortex Alleviation Using A Reverse Delta Type Add-On Device, Afaq Altaf

International Journal of Aviation, Aeronautics, and Aerospace

The result of interactions of a wingtip vortex of a half-span wing and vortices generated by a slender reverse delta type add-on device were studied using Particle Image Velocimetry in a closed-loop low-speed wind tunnel. Characteristics of the vortex interactions produced downstream in planes perpendicular to the free stream direction at a mean chord-based Reynolds number, Re_c = 2.75×10⁵, are explored in this work. The study reveals that the reverse delta type add-on device considerably reduces the tangential velocity, vorticity and circulation magnitude of the resultant vortex by up to 79.6%, 85.6% and 48.7%, respectively. It was …

The Effect Of Engineered Nanotopography Of Electrospun Microfibers On Fiber Rigidity And Macrophage Cytokine Production, Nicholas J. Schaub, Anthony R. D'Amato, Andrew Mason, David T. Corr, Erin Y. Harmon, Michelle R. Lennartz, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Currently, it is unknown how the mechanical properties of electro spun fibers, and the presentation of surface nano topography influence macrophage gene expression and protein production. By further elucidating how specific fiber properties (mechanical properties or surface properties) alter macrophage behavior, it may be possible to create electro spun fiber scaffolds capable of initiating unique cellular and tissue responses. In this study, we determined the elastic modulus and rigidity of fibers with varying topographies created by finely controlling humidity and including a non-solvent during electrospinning. In total, five fiber scaffold types were produced. Analysis of fiber physical properties demonstrated no …

Combined Model Predictive Control And Scheduling With Dominant Time Constant Compensation, Logan Beal, Junho Park, Damon Petersen, Sean C. Warnick, John Hedengren

Faculty Publications

Linear model predictive control is extended to both control and optimize a product grade schedule. The proposed methods are time-scaling of the linear dynamics based on throughput rates and grade-based objectives for product scheduling based on a mathematical program with complementarity constraints. The linear model is adjusted with a residence time approximation to time-scale the dynamics based on throughput. Although nonlinear models directly account for changing dynamics, the model form is restricted to linear differential equations to enable fast online cycle times for large-scale and real-time systems. This method of extending a linear time-invariant model for scheduling is designed for …

Design And Validation Of A Low Cost High Speed Atomic Force Microscope, Michael Ganzer, Tien Pham

Journal of Undergraduate Research at Minnesota State University, Mankato

The Atomic Force Microscope (AFM) is an important instrument in nanoscale topography, but it is expensive and slow. The authors designed an AFM to overcome both limitations. To do this, they used an Optical Pickup Unit (OPU) from a DVD player as the laser and photodetector system to minimize cost and they did not implement a vertical control loop, which maximized potential speed. Students will be able to be use this device to make nanoscale measurements and engage in micro-engineering. To prototype this idea, the authors tested an OPU with a silicon wafer and demonstrated the ability to consistently distinguish …

Improving Speech Recognition For Interviews With Both Clean And Telephone Speech, Sung Woo Choi

Journal of Undergraduate Research at Minnesota State University, Mankato

High quality automatic speech recognition (ASR) depends on the context of the speech. Cleanly recorded speech has better results than speech recorded over telephone lines. In telephone speech, the signal is band-pass filtered which limits frequencies available for computation. Consequently, the transmitted speech signal may be distorted by noise, causing higher word error rates (WER). The main goal of this research project is to examine approaches to improve recognition of telephone speech while maintaining or improving results for clean speech in mixed telephone-clean speech recordings, by reducing mismatches between the test data and the available models. The test data includes …

Stem Gateway Peer Learning Facilitators Professional Development Curriculum, Janeth Pena

STEM Gateway

The learning object is a collection of professional development presentations and resources for guiding staff and faculty in training and implementing a Peer Learning Facilitators program, as developed by the STEM Gateway Program, intended for use within an Active Learning classroom environment. The materials were designed and implemented during the University of New Mexico STEM Gateway Project, funded by the U.S. Department of Education Title V program during 2012-2016.

Physical Water Scarcity Metrics For Monitoring Progress Towards Sdg Target 6.4: An Evaluation Of Indicator 6.4.2 “Level Of Water Stress”, D. Vanhama, A. Y. Hoekstra, Y. Wada, F. Bouraoui, A. De Roo, Mesfin Mekonnen, W. J. Van De Bund, O. Batelaan, P. Pavelic, W. G.M. Bastiaanssen, M. Kummu, J. Rockström, J. Liu, B. Bisselink, P. Ronco, A. Pistocchi, G. Bidoglio

Daugherty Water for Food Global Institute: Faculty Publications

Target 6.4 of the recently adopted Sustainable Development Goals (SDGs) dealswith the reduction ofwater scarcity. To monitor progress towards this target, two indicators are used: Indicator 6.4.1 measuring water use efficiency and 6.4.2 measuring the level of water stress (WS). This paper aims to identify whether the currently proposed indicator 6.4.2 considers the different elements that need to be accounted for in a WS indicator.WS indicators compare water use with water availability.We identify seven essential elements: 1) both gross and net water abstraction (or withdrawal) provide important information to understand WS; 2) WS indicators need to incorporate environmental flow requirements …

Revealing Casual Pathways To Sustainable Water Service Delivering Using Fsqca, Kate E. Gasparro, Jeffrey P. Walters

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

This study aimed to build on theory and practice regarding the combinations of conditions that influence water service sustainability when external partners are involved. The study investigates 26 well projects that have been implemented in developing countries with the assistance of Engineers Without Borders-USA (EWB-USA). Using past literature on sustainable water service delivery in developing communities, emergent coding techniques with project documents, and surveys with EWB-USA team members, this study identifies a set of project conditions to conduct fuzzy-set Qualitative Comparative Analysis (fsQCA). Findings show that the presence of a water committee cannot alone account for project sustainability. Additional conditions, …

The Use Of Persistent Explorer Artificial Ants To Solve The Car Sequencing Problem, Kieran O'Sullivan

Dissertations

Ant Colony Optimisation is a widely researched meta-heuristic which uses the behaviour and pheromone laying activities of foraging ants to find paths through graphs. Since the early 1990’s this approach has been applied to problems such as the Travelling Salesman Problem, Quadratic Assignment Problem and Car Sequencing Problem to name a few. The ACO is not without its problems it tends to find good local optima and not good global optima. To solve this problem modifications have been made to the original ACO such as the Max Min ant system. Other solutions involve combining it with Evolutionary Algorithms to improve …

Advanced Energy Storage Technologies And Their Applications (Aesa2017), Rui Xiong, Hailong Li, Xuan Joe Zhou

Electrical & Computer Engineering Publications

This editorial summarizes the performance of the special issue entitled Advanced Energy Storage Technologies and Applications (AESA), which is published in MDPI’s Energies journal in 2017. The special issue includes a total of 22 papers from four countries. Lithium-ion battery, electric vehicle, and energy storage were the topics attracting the most attentions. New methods have been proposed with very sound results.

Computerized Heat Transfer Modeling For Solar Powered Water Purification System, Houtan Neynavaee

Mechanical Engineering Master's Theses

Since drinkable water resources are limited, as the human population increases it is predicted that providing pure water is a future human challenge. However, a huge resource of the water exists on the earth surface in seas and oceans, which are not proper for drinking and cultivate. Exploiting of a solar powered water purification system is an economy and environment-friendly solution to this human problem.

In this thesis, we present computerized heat transfer model for solar powered water purification system. This Model can be used for calculating the heat transfer, system temperature, and other variable parameters such as boiler pressure, …

Inspire E-News 9 2017, College Of Engineering And Applied Sciences

College of Engineering and Applied Sciences News

• Win Tickets to WMU's Homecoming Game!
• College hosts paper coatings course for industry professionals
• Scholarship winner seeks adventure abroad

Convergence Of The Fast State Estimation For Power Systems, Md Ashfaqur Rahman, Ganesh Kumar Venayagamoorthy

Publications

Power system state estimation is a fundamental computational process that requires both speed and reliability. To meet the needs, some variants of the constant Jacobian methods have been used in the industry over the last several decades. The variants work very well under normal operating conditions with nominal values of the states. However, the convergence of the methods are not analysed mathematically and it may contain pitfalls. In this study, the convergence of the constant Jacobian methods are analysed and it is shown that the methods fail under high variations of the states. To increase the reliability of the processes, …

A Sustainable Approach For Tungsten Carbide Synthesis Using Renewable Biopolymers, Monsur Islam, Rodrigo Martinez-Duarte

Publications

Here we present a sustainable, environment-friendly and energy-efficient approach for synthesis of porous tungsten carbide (WC). A biopolymer-metal oxide composite featuring iota-carrageenan, chitin and tungsten trioxide (WO3) was used as the precursor material. The reaction mechanism for the synthesis of WC was estimated using the results from X-ray diffraction characterization (XRD). A synthesis temperature of 1300 °C and dwell time of 3 h were found to be the optimum process parameters to obtain WC>98% pure. The grain size, porosity and Brunauer–Emmett–Teller (BET) surface area of the synthesized WC were characterized using field emission scanning electron microscopy, high resolution transmission …

Probabilistic Graphical Models Follow Directly From Maximum Entropy, Anh H. Ly, Francisco Zapata, Olac Fuentes, Vladik Kreinovich

Departmental Technical Reports (CS)

Probabilistic graphical models are a very efficient machine learning technique. However, their only known justification is based on heuristic ideas, ideas that do not explain why exactly these models are empirically successful. It is therefore desirable to come up with a theoretical explanation for these models' empirical efficiency. At present, the only such explanation is that these models naturally emerge if we maximize the relative entropy; however, why the relative entropy should be maximized is not clear. In this paper, we show that these models can also be obtained from a more natural -- and well-justified -- idea of maximizing …

Truck Routing Issues, Kenneth R. Agent

Kentucky Transportation Center Research Report

Commercial vehicle drivers selecting inappropriate routes where the handling characteristics (e.g., off-tracking) and dimensions of their trucks are not consistent with a roadway’s cross section and geometrics can damage the vehicle, harm adjacent property, or result in crashes. Analysis of crashes that involve the use of inappropriate routes indicate a significant number are caused by drivers receiving faulty directions from in-truck GPS units or adhering to incorrect directions provided by their companies. The Kentucky Transportation Center (KTC) investigated strategies to ensure truck drivers are given correct directions when traveling on Kentucky roadways. As part of this effort, this report reviews …

Degradation Of Bisphenol-A By Dielectric Barrier Discharge System: Influence Of Polyethylene Glycol Stabilized Nano Zero Valent Iron Particles, Jimoh O. Tijani, Massima E.S. Mouele, Ojo O. Fatoba, Omotola O. Babajide, Leslie F. Petrik

Mining Engineering Faculty Research & Creative Works

In this study we report the synthesis and catalytic properties of polyethylene glycol stabilized nano zero valent iron particles (PEG-nZVI) added to the dielectric barrier discharge (DBD) system to induce photo-Fenton process in the degradation of bisphenol A (BPA) in aqueous solution. The influence of operating parameters such as solution pH, initial concentration of the modelled pollutant and PEG-nZVI dosage on the extent of BPA degradation was investigated. The residual concentration of BPA and its intermediates were determined using high performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LCMS). The high-resolution scanning electron microscope (HRSEM), x-ray diffraction (XRD), Brunauer-Emmett-Teller …

Dpm Dispersion Inside A Single Straight Entry Using Dynamic Mesh Model, Yi Zheng, Ying Li, Magesh Thiruvengadam, Hai Lan, Jerry C. Tien

Mining Engineering Faculty Research & Creative Works

Three-dimensional simulations of diesel particulate matter (DPM) distribution inside a single straight entry for the Load-Haul-Dump loader (LHD)-truck loading and truck hauling operations were conducted by using ANSYS FLUENT computational fluid dynamics software. The loading operation was performed for a fixed period of 3 min. The dynamic mesh technique in FLUENT was used to study the impact of truck motion on DPM distribution. The resultant DPM distributions are presented for the cases when the truck was driving upstream and downstream of the loading face. Interesting phenomena were revealed in the study including the piston effect, layering of DPM in the …

The Effects Of Chemical Coagulants On The Decolorization Of Dyes By Electrocoagulation Using Response Surface Methodology (Rsm), Erick B. Butler, Yung-Tse Hung, Oliver Mulamba

Civil and Environmental Engineering Faculty Publications

This study assessed the efficiency of electrocoagulation (ECF) coupled with an addition of chemical coagulant to decolorize textile dye. Tests were conducted using Box Behnken methodology to vary six parameters: dye type, weight, coagulant type, dose, initial pH and current density. The combination of electrocoagulation and chemical coagulation was able to decolorize dye up to 99.42 % in 30 min of treatment time which is remarkably shorter in comparison with using conventional chemical coagulation. High color removal was found to be contingent upon the dye type and current density, along with the interactions between the current density and the coagulant …

Chaos-Based Encryption Keys And Neural Key-Store For Cloud-Hosted Data Confidentiality, N.N Mosola, M.T Dlamini, Jonathan Blackledge, J.H.P Eloff, H.S Venter

Conference papers

Cloud computing brings flexible and cost-effective services. However, security concerns plague the cloud. Data confidentiality is one of the security concerns inhibiting the adoption of cloud computing. This concern stems from various cyberattacks directed towards gaining unauthorised access to cloud-bound or cloud-hosted data. This paper proposes a clientend encryption and key management system to curb cyberattacks that target compromising data confidentiality on the cloud.

Impulse, Matt Schmidt, Lora Berg, Christine Delfanian, Dave Graves, Heidi Kronaizl, Emily Weber, Micayla Standish

Impulse (Jerome J. Lohr College of Engineering Publication)

[Page] 2 Better Equipped
[Page] 4 Flashback Summer Scholars
[Page] 6 Biomedical Engineering
Ryan Mahutga is the third mechanical engineering graduate in five years to receive a prestigious National Science Foundation Graduate Research Fellowship.
Nigerian native John Asiruwa is working with associate professor Stephen Gent on a mechanical engineering project to help Sanford Health build better heart stents.
Electrical engineering graduate Bruce Lutz has selected the biomedical engineering program as a target for his future giving.
[Page] 9 Programs Accredited
[Page] 10 Fast Wheels
[Page] 12 Five Unforgettable Weeks
[Page] 14 Second in the Nation
[Page] 16 Athletes and Engineering …

Direct Numerical Simulation Of Turbulent Katabatic Slope Flows With An Immersed-Boundary Method, Clancy Umphrey, Ray Deleon, Inanc Senocak

Mechanical and Biomedical Engineering Faculty Publications and Presentations

We investigate a Cartesian-mesh immersed-boundary formulation within an incompressible flow solver to simulate laminar and turbulent katabatic slope flows. As a proof-of-concept study, we consider four different immersed-boundary reconstruction schemes for imposing a Neumann-type boundary condition on the buoyancy field. Prandtl’s laminar solution is used to demonstrate the second-order accuracy of the numerical solutions globally. Direct numerical simulation of a turbulent katabatic flow is then performed to investigate the applicability of the proposed schemes in the turbulent regime by analyzing both first- and second-order statistics of turbulence. First-order statistics show that turbulent katabatic flow simulations are noticeably sensitive to the …

A Systems-Based Framework For Design And Analysis Of An R And D Structure, Polinpapilinho F. Katina, Charles B. Keating, Luna M. Magpili

Engineering Management & Systems Engineering Faculty Publications

A critical challenge for managerial effectiveness and competitive advantage in research and development (R and D) organizations is developing an appropriate structural configuration. However, in finding an appropriate structural configuration, R and D managers are faced with unprecedented levels of uncertainty, ambiguity, and accelerating complexity, coupled with demands for increased productivity. This paper develops a systems-based framework to support rigorous design, analysis, and transformation of the structure for R and D organizations. The framework development includes: (1) a review of the literature for the nature and role of the structure in R and D management; (2) setting of the R …