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Full-Text Articles in Engineering

Multi-Period Liner Ship Fleet Planning With Dependent Uncertain Container Shipment Demand, Qiang Meng, Tingsong Wang, Shuaian Wang Jun 2015

Multi-Period Liner Ship Fleet Planning With Dependent Uncertain Container Shipment Demand, Qiang Meng, Tingsong Wang, Shuaian Wang

Faculty of Engineering and Information Sciences - Papers

This paper deals with a realistic multi-period liner ship fleet planning problem by incorporating stochastic dependency of the random and period-dependent container shipment demand. This problem is formulated as a multi-period stochastic programming model with a sequence of interrelated two-stage stochastic programming (2SSP) problems characterized ship fleet planning in each single period. A solution method integrating dual decomposition and Lagrangian relaxation method is designed for solving the developed model. Numerical experiments are carried out to assess applicability and performance of the proposed model and solution algorithm. The results further demonstrate importance of stochastic dependence of the uncertain container shipment demand.


An Innovation Formula For Privately Held Mid-Sized Companies, Jennifer Brusso Dec 2014

An Innovation Formula For Privately Held Mid-Sized Companies, Jennifer Brusso

Theses and Dissertations

The principal objective of this paper is to create an innovation formula that streamlines and optimizes the innovation process in mid-sized privately held companies. Research included case studies of three privately held mid-sized companies. A comparison and analysis was completed on how each of the companies innovate, the success of methods used, and their ability to adapt to adversity. To address the increasing demand for innovative products and services that privately held mid-sized companies need to deliver on, information taken from the case studies was utilized to derive an innovation formula that focuses on customer engagement, professional affiliations, and open ...


A Novel Transport Based Model For Wire Media And Its Application To Scattering Problems, Ebrahim Forati Dec 2014

A Novel Transport Based Model For Wire Media And Its Application To Scattering Problems, Ebrahim Forati

Theses and Dissertations

Artificially engineered materials, known as metamaterials, have attracted the interest of researchers because of the potential for novel applications. Effective modeling of metamaterials is a crucial step for analyzing and synthesizing devices. In this thesis, we focus on wire medium (both isotropic and uniaxial) and validate a novel transport based model for them.

Scattering problems involving wire media are computationally intensive due to the spatially dispersive nature of homogenized wire media. However, it will be shown that using the new model to solve scattering problems can simplify the calculations a great deal.

For scattering problems, an integro-differential equation based on ...


Monitoring Changes In Hemodynamics Following Optogenetic Stimulation, Seth Thomas Frye Dec 2014

Monitoring Changes In Hemodynamics Following Optogenetic Stimulation, Seth Thomas Frye

Theses and Dissertations

The brain is composed of billions of neurons, all of which connected through a vast network. After years of study and applications of different technologies and techniques, there are still more questions than answers when it comes to the fundamental functions of the brain. This project aims to provide a new tool which can be used to gain a better understanding of the fundamental mechanisms that govern neurological processes inside the brain. In order for neural networks to operate, blood has to be supplied through neighboring blood vessels. As such, the increase or decrease in the blood supply has been ...


Real-Time Analysis And Control Of Serial Production Lines For Energy Efficient Manufacturing, Guorong Chen Dec 2014

Real-Time Analysis And Control Of Serial Production Lines For Energy Efficient Manufacturing, Guorong Chen

Theses and Dissertations

Productivity analysis, operation control and energy consumption reduction

have been the central topics in manufacturing research and practice. They are closely related to each other. Control of production operations is considered as one of the most economical methods to improve energy efficiency in manufacturing systems, while system performance analysis serves as the base of production control. On the other hand, effective operation control can result to energy efficiency in manufacturing.

Steady state analysis has been investigated extensively; however, transient analysis remained largely unexplored. Our research focuses on system modeling, performance analysis, and real-time operation control of serial production lines with ...


Nonlinear Processes In Multi-Mode Optical Fibers, Hamed Pourbeyram Kaleibar Dec 2014

Nonlinear Processes In Multi-Mode Optical Fibers, Hamed Pourbeyram Kaleibar

Theses and Dissertations

Nonlinear processes in optical fibers can affect data transmission and power carried by

optical fibers and can limit the bandwidth and the capacity of optical communications.

On the other hand nonlinear phenomena could be utilized to build in-fiber all-optical

light sources and amplifiers. In this thesis new peaks inside an optical fiber have been

generated using nonlinear processes. An intense green pump laser has been launched

into a short fiber and specific modes have been excited to generate two new peaks in

red and blue wavelengths, where two pump photons are annihilated to create two new

photons in red and ...


Design Of A Micro-Focus X-Ray Source Validated By Model Protein Crystals, Lavanya Ramachandran Dec 2014

Design Of A Micro-Focus X-Ray Source Validated By Model Protein Crystals, Lavanya Ramachandran

Theses and Dissertations

The main objective of this thesis was to build a Laboratory Microfocus X-ray Source for Protein Crystallography (LMXS-PC), an X-ray source that would provide prospective users programmatic control and remote capability.

A study of the crystal was conducted using Photoactive Yellow protein (PYP) and cytochrome c nitrite reductase (ccNiR). The instrument was then tested by mounting the crystal in the instrument and collecting data.

The other objective of my research work was to determine the crystal structure of PYP using X-ray crystallography techniques. I attempted many trials in PYP crystal in an effort to achieve a high-quality diffraction pattern; however ...


Development Of Novel Passive Control Techniques For More Uniform Temperature At Combustor Exit And Hybrid Les/Rans Modeling, Alka Gupta Dec 2014

Development Of Novel Passive Control Techniques For More Uniform Temperature At Combustor Exit And Hybrid Les/Rans Modeling, Alka Gupta

Theses and Dissertations

Gas turbines have become an important, widespread, and reliable device in the field of power generation. For any gas turbine system, the combustor is an integral part responsible for the combustion of the fuel. A number of studies have shown that the flow field exiting a combustor is highly non-uniform in pressure, velocity and, most importantly, temperature. Hot streaks amongst other non-uniformities cause varying thermal stresses on turbine blades and put pressure on the blade materials. In particular, these non-uniformities can have detrimental effects on the performance of the engine and cause a reduction in the expected life of critical ...


Transverse Anderson Localization In Disordered Optical Fibers, Salman Karbasivalashani Dec 2014

Transverse Anderson Localization In Disordered Optical Fibers, Salman Karbasivalashani

Theses and Dissertations

In any wave-guiding system, disorder and randomness in the wave propagation medium are

considered as annoyances that result in wave scattering and inefficient wave transport. In contrast, in this work, the disorder is utilized in the transverse directions of an optical fiber for an effective light transport. The transversely disordered refractive index profile is invariant along the direction of propagation that results in transverse Anderson localization of light. A launched beam of light into the disordered fiber initially expands until it reaches the localization regime then propagates without further expansion in the transverse directions.

A disordered polymer optical fiber composed ...


Improved Wind Turbine Control Strategies For Maximizing Power Output And Minimizing Power Flicker, Quan Chen Dec 2014

Improved Wind Turbine Control Strategies For Maximizing Power Output And Minimizing Power Flicker, Quan Chen

Theses and Dissertations

For reducing the cost of energy (COE) for wind power, controls techniques are important for enhancing energy yield, reducing structural load and improving power quality. This thesis presents the control strategies studies for wind turbine both from the perspectives of both maximizing power output and reducing power flicker and structural load,

First, a self-optimizing robust control scheme is developed with the objective of maximizing the power output of a variable speed wind turbine with doubly-fed induction generator (DFIG) operated in Region 2. Wind power generation can be divided into two stages: conversion from aerodynamic power to rotor (mechanical) power and ...


Evaluation Of Employment Benefits Of Ultra-Heavy Trucks: Wisconsin Case Study, Katrina Maria Kurniati Dec 2014

Evaluation Of Employment Benefits Of Ultra-Heavy Trucks: Wisconsin Case Study, Katrina Maria Kurniati

Theses and Dissertations

Allowing very heavy trucks, without permits, on United States' highways has been a subject of discussion in the past, and many politicians and industry advocates have argued that there are some benefits to much heavier trucks. Benefits include better air quality, reduced fuel usage, and increased industrial efficiency. The economic analysis of heavier trucks, however, remains incomplete. One way to measure economic benefits is by assessing employment growth. Wisconsin is used as a case study to evaluate employment benefits of ultra-heavy trucks. The current regulation of the maximum gross vehicle weight on all axles in Wisconsin is 80,000 pounds ...


Enhancement To Camera Calibration: Representation, Robust Statistics, And 3d Calibration Tool, Qiaotian Li Dec 2014

Enhancement To Camera Calibration: Representation, Robust Statistics, And 3d Calibration Tool, Qiaotian Li

Theses and Dissertations

This thesis demonstrates the enhancement to camera calibration in three aspects: representation of pose, robust statistics and 3D calibration tool. Camera calibration is the reconstruction of digital camera information based on digital images of an object in 3D space, since the digital images are 2D projections of a 3D object onto the camera sensor. Camera calibration is the estimation of the interior orientation (IO) parameters and exterior orientation (EO) parameters of a digital camera. Camera calibration is an essential part of image metrology. If the quality of camera calibration cannot be guaranteed, neither can the reliability of the subsequent analysis ...


Evaluation Of Pavement Performance Due To Overload Single Trip Permit Truck Traffic In Wisconsin, Valbon Latifi Dec 2014

Evaluation Of Pavement Performance Due To Overload Single Trip Permit Truck Traffic In Wisconsin, Valbon Latifi

Theses and Dissertations

This study researched the impacts of overweight permit vehicle traffic on flexible pavement performance in Wisconsin using field investigations and AASHTOWare MEPDG analyses. A database of Oversize/Overweight (OSOW) single trip permit truck records was analyzed and provided a network of Wisconsin corridors heavily trafficked by OSOW trucks. Four Wisconsin state trunk highways were selected for investigation due to a high level of OSOW truck traffic. The research included traffic counts to confirm the levels of truck traffic on these segments and to verify the high numbers of permits issued for OSOW trucks. Furthermore, the field work included the identification ...


Nyiso – Selected Topics, Dejan Sobajic Oct 2014

Nyiso – Selected Topics, Dejan Sobajic

Modeling, Simulation, And Optimization for the 21st Century Electric Power Grid

No abstract provided.


Injectable, Magnetic Plum Pudding Hydrogel Composites For Controlled Pulsatile Drug Release, Danielle Maitland Oct 2014

Injectable, Magnetic Plum Pudding Hydrogel Composites For Controlled Pulsatile Drug Release, Danielle Maitland

Open Access Dissertations and Theses

Injectable, in-situ gelling magnetic plum pudding hydrogel composites were fabricated by entrapping superparamagnetic iron oxide nanoparticles (SPIONs) and thermosensitive N-isopropylacrylamide (NIPAM)-co–N-isopropylmethacrylamide (NIPMAM) microgels in a pNIPAM-hydrazide/carbohydrate-aldehyde hydrogel matrix. The resulting composites exhibited significant, repeatable pulsatile release of 4 kDa FITC-dextran upon exposure to an alternating magnetic field. The pulsatile release from the composites could be controlled by altering the volume phase transition temperatures of the microgel particles (with VPTTs over 37°C corresponding to improved pulsatile release) and changing the microgel content of the composite (with higher microgel content corresponding to higher pulsatile release). By changing the ...


Measurement And Prediction Of The Onset Of Intermittent Dryout During Blowdown Transients For Upward Annular Flow, Bradley A. Statham Oct 2014

Measurement And Prediction Of The Onset Of Intermittent Dryout During Blowdown Transients For Upward Annular Flow, Bradley A. Statham

Open Access Dissertations and Theses

The effect of pressure transients on the onset of intermittent dryout in upward annular flow was experimentally investigated in order to resolve the conflict between the observations drawn from two major data sets in the literature. A delay in time to the onset of dryout at the test section exit relative to the time predicted based on steady-state data was observed in the R-12 experiments of Celata et al (1988; 1991). Steady-state prediction methods were sufficient to predict the upstream progression of a pre-existing dryout front in the water experiments of Lyons and Swinnerton (1983). Steady state and pressure transient ...


A Multi-Well Concentration Gradient Drug Delivery Microfluidic Device For High-Content And High-Throughput Screening, Michael M. Nelson Oct 2014

A Multi-Well Concentration Gradient Drug Delivery Microfluidic Device For High-Content And High-Throughput Screening, Michael M. Nelson

Open Access Dissertations and Theses

A microfluidic device capable of drug delivery to multiple wells in a concentration gradient was designed for automated high content and high throughput screening. The design was proposed to utilize a nanoporous polycarbonate membrane to spatially and temporally control drug dosage from the microchannels below to the wells above. Microchannels were to hold to the drugs or reagents, while wells were to culture cells. An array of 16 wells was to fit in the equivalent area of a single well of a 96 well plate. Two simpler devices were created to validate electrokinetic drug delivery to a single well and ...


Explicit Solution Of The Large Amplitude Transverse Vibrations Of A Flexible String Under Constant Tension, Ali Nikkar, Reza Taghipour, Tohid Akhlaghi Sep 2014

Explicit Solution Of The Large Amplitude Transverse Vibrations Of A Flexible String Under Constant Tension, Ali Nikkar, Reza Taghipour, Tohid Akhlaghi

Ali Nikkar

This paper presents the analytical simulation of string with large amplitudes using the Variational Iteration Method (VIM) and Hamiltonian Approach (HA). In order to verify the precision of the presented methods, current results were compared with He’s Variational Approach and Runge-Kutta 4th order. It has been found that these methods are well suited for a range of parameters and the approximate frequencies and periodic solutions show a good agreement with other techniques. The results show that both methods can be easily extended to other nonlinear oscillations and it can be predicted that both methods can be found widely applicable ...


Structural And Catalytic Differences In The Effect Of Co And Mo As Promoters For Pt-Based Aqueous Phase Reforming Catalysts, Paul J. Dietrich, Fred G. Sollberger, M. Cem Akatay, Eric A. Stach, W.Nicholas Delgass, Jeffrey T. Miller, Fabio H. Ribeiro Sep 2014

Structural And Catalytic Differences In The Effect Of Co And Mo As Promoters For Pt-Based Aqueous Phase Reforming Catalysts, Paul J. Dietrich, Fred G. Sollberger, M. Cem Akatay, Eric A. Stach, W.Nicholas Delgass, Jeffrey T. Miller, Fabio H. Ribeiro

Birck and NCN Publications

Reaction rates (site time yields, normalized to CO chemisorption sites) and product selectivity were determined for PtCo, PtMo, and Pt supported on multi-walled carbon nanotubes for aqueous phase reforming of glycerol. The bimetallic PtCo and PtMo catalysts had 4.6x and 5.4x higher glycerol consumption rates than Pt, and 3.9x and 0.6x rates in H-2 formation compared to Pt. Hydrogen generation selectivity was similar on Pt and PtCo, but PtMo had an increase in selectivity to C-O cleavage products, which reduced H-2 yield at conversions over 60% (85-90% hydrogen yield for Pt and PtCo, 65% for PtMo ...


Failures Of Mainline Railway Sleepers And Suggested Remedies-Review Of Current Practice, Wahid Ferdous Sep 2014

Failures Of Mainline Railway Sleepers And Suggested Remedies-Review Of Current Practice, Wahid Ferdous

Wahid Ferdous

Over the last two decades, the premature failures of traditional railway sleepers have significantly increased the track maintenance costs. The primary obstacle to minimising this problem is the lack of understanding of the mechanism of sleeper degradation. This paper discusses the different deterioration mechanisms for traditional timber, concrete and steel sleepers and the potential protective measures to minimise these problems. This paper exhaustively reviews the failure mechanisms of these three commonly used sleeper materials with suggested solutions. Fungal decay, end splitting and termite attacks has been identified as the principal causes of timber sleeper failures. On the other hand, concrete ...


Implementation And Validation Of Aortic Remodeling In Hypertensive Rats, Shijia Zhao, Linxia Gu Sep 2014

Implementation And Validation Of Aortic Remodeling In Hypertensive Rats, Shijia Zhao, Linxia Gu

Mechanical & Materials Engineering Faculty Publications

A computational framework was implemented and validated to better understand the hypertensive artery remodeling in both geometric dimensions and material properties. Integrating the stress-modulated remodeling equations into commercial finite element codes allows a better control and visualization of local mechanical parameters. Both arterial thickening and stiffening effects were captured and visualized. An adaptive material remodeling strategy combined with the element birth and death techniques for the geometrical growth were implemented. The numerically predicted remodeling results in terms of the wall thickness, inner diameter, and the ratio of elastin to collagen content of the artery were compared with and fine-tuned by ...


Research Posters 2014, Spelman College G-Stem Aug 2014

Research Posters 2014, Spelman College G-Stem

Posters

This document contains 11 research posters from the Research Day 2014 research cohort. Should you seek full-length copies of the research papers, please email the G-STEM program at gstem@spelman.edu as any rights related to research or copyrighting remains with the research sponsors, authors and the host institution for the research and permission for distribution must be granted by each for said request.


Enhancing Global Research And Education In Stem At Spelman College: Abstracts 2013, Spelman College G-Stem Aug 2014

Enhancing Global Research And Education In Stem At Spelman College: Abstracts 2013, Spelman College G-Stem

Abstracts

The abstracts contained within this document represent the research abstracts of 23 Spelman G-STEM Cohort participants from Summer 2013 – Fall 20132.Should you seek full-length copies of the research papers, please email the G-STEM program at gstem@spelman.edu as any rights related to research or copyrighting remains with the research sponsors, authors and the host institution for the research and permission for distribution must be granted by each for said request.


Design And Development Of A Miniature In Vivo Surgical Robot With Distributed Motor Control For Laparoendoscopic Single-Site Surgery, Eric J. Markvicka Aug 2014

Design And Development Of A Miniature In Vivo Surgical Robot With Distributed Motor Control For Laparoendoscopic Single-Site Surgery, Eric J. Markvicka

Mechanical (and Materials) Engineering -- Dissertations, Theses, and Student Research

Paradigm shifts in invasiveness, recovery time, cosmesis, and cost have been seen within the field of general surgery through major advances in surgical technology. Some of the most advanced types of general surgery now include Minimally Invasive Surgery (MIS), LaparoEndoscopic Single-Site (LESS) surgery, and Natural Orifice Translumenal Endoscopic Surgery (NOTES). One of the newest and rapidly developing catalysts is robotic platforms. Such platforms have improved ergonomics and control, increased workspace and dexterity, and have surpassed the efficacy of many non-robotic platforms such as traditional laparoscopic surgical tools. This thesis presents the design and development of a four-degree-of-freedom (4- DOF) miniature ...


Instrumentation To Monitor Bridge Foundation On The Crosstown Project, Brian Welch Aug 2014

Instrumentation To Monitor Bridge Foundation On The Crosstown Project, Brian Welch

Journal of Undergraduate Research at Minnesota State University, Mankato

The Crosstown Bridge Monitoring Project is located at the intersection of Highway 62 and Interstate I35W a few miles south and west of downtown Minneapolis. The bridge being evaluated is at a railroad overpass located midway along the Crosstown expansion. This research project involved placing instrumentation on the bridge foundation in order to measure the change in the foundation loading during the course of the construction project. For several years there have been questions pertaining to the forces in the pile foundations that support highway embankments. This project placed strain gages on the pile foundations in order to monitor these ...


Assessment Of Policies For Innovative Financing In Infrastructure Systems, Ali Mostafavi, Dulcy Abraham, Charlene Sullivan Aug 2014

Assessment Of Policies For Innovative Financing In Infrastructure Systems, Ali Mostafavi, Dulcy Abraham, Charlene Sullivan

Infrastructure System-of-Systems (I-SoS ) Research Group

Infrastructure systems are drivers of the economy in the nation. A dollar spent on infrastructure development yields roughly double the initial spending in ultimate economic output in the short term; and over a twenty-year period, and generalized ‘public investment’ produces an aggregated $3.21 of economic activity per $1.00 spent [1]. Thus, formulation of policies pertaining to infrastructure investment and development is of significance affecting the social and economic wellbeing of the nation. The aim of this policy brief is to evaluate innovative financing in infrastructure systems from two different perspectives: (1) through consideration of the current condition of ...


Turbulent Circular Culvert Flow: Implications To Fish Passage Design, Amin Mohebbi Aug 2014

Turbulent Circular Culvert Flow: Implications To Fish Passage Design, Amin Mohebbi

Civil Engineering Theses, Dissertations, and Student Research

Culverts are popular conveyance structures in America and Canada to be used as a fish passage or in sewage collection and disposal systems. Fish passage design criteria is based on biological capabilities of fish whereas it should satisfy hydraulic and hydrological constraints as well. Failing to provide enough low velocity regions for aquatic organisms may result in their mass extinctions. Currently, proper road crossing design depends on either model studies or numerical simulations via Computational Fluid Dynamic (CFD) packages, both of which are expensive and time consuming. Further, although the design procedures released by FHWA recently ensures safe fish migration ...


Numerical Analysis Of Two Phase Flow And Heat Transfer In Condensers, Pooya Mirzabeygi Aug 2014

Numerical Analysis Of Two Phase Flow And Heat Transfer In Condensers, Pooya Mirzabeygi

University of Western Ontario - Electronic Thesis and Dissertation Repository

Steam surface condensers are commonly used in the power generation industry and their performance significantly affects the efficiency of the power plant. Therefore, it is vital to acquire a better understanding of the complex phenomena occurring inside condensers. A general three-dimensional numerical model is developed in this study to simulate the two-phase flow and heat transfer inside full-scale industrial condensers with irregular tube bundle shapes. The Eulerian-Eulerian two-phase model is selected to simulate gas and liquid flows and the interaction between them. A porous media approach is adopted to model the presence of large number of tubes in the condenser ...


Three Dimensional Transient Asymmetric Flowfields In Physical Vapor Transport, Joseph Dobmeier Aug 2014

Three Dimensional Transient Asymmetric Flowfields In Physical Vapor Transport, Joseph Dobmeier

Journal of Undergraduate Research at Minnesota State University, Mankato

Physical Vapor Transport is a manufacturing process used to produce single crystals of semiconductor materials such as mercurous chloride (Hg2Cl2). In the past this time-varying process has been studied with numerical simulation by considering three dimensional flow using an axi-symmetric two dimensional model or by restricting the simulation to asymmetric two dimensional flow and dropping the assumption of axi-symmetry from the model. It is generally agreed that neither of these methods accurately represent the true behavior of the process. The purpose of this research was to extend the asymmetric two dimensional model to three dimensions thereby obtaining a solution which ...


Work In Progress - Peer Directed Learning In A Project Based Model, Andrew Mcnally Aug 2014

Work In Progress - Peer Directed Learning In A Project Based Model, Andrew Mcnally

Journal of Undergraduate Research at Minnesota State University, Mankato

Iron Range Engineering is a new, unique, undergraduate program using problem-based learning. One guiding principle is student responsibility for learning. In order to facilitate learning, faculty and students alike have come up with several learning methods. Learning modes may include self-directed learning, peer-directed learning, one-on-one faculty directed learning, or industry mentored learning. Peer directed learning often manifests in the form of learning groups (a group of students learning similar competencies), led by either a faculty member or a student who has previously excelled in that competency and has taken an interest in pursuing advanced credit. Recently, Iron Range Engineering has ...