Engineering Commons^™

Dislocation Substructures Of Interstitial-Free Steel Subjected To Low Cycle Fatigue At Various Strain Amplitude, Shih-Wei Mao, Wen-Chun Lo, Hsing-Lu Huang, New-Jin Ho

Journal of Marine Science and Technology–Taiwan

The aim of this wok is to study the fatigue properties in relation to the microstructures of interstitial-free (IF) steel, a representative of body center cubic (BCC) materials, subjected to low cycle periodic stress. In order to compare the grain size effect on dislocation development, we used samples of two distinctive grain sizes, 70 µm and 210 µm, prepared by different thermo-mechanical processes. We found (1) there was an initial softening when the stain amplitude was lower than 1.6% and the microstructure of the fatigued samples are cellular independent of the grain sizes and the amplitude of strain. (2) A …

Zener-Stroh Crack Problem In A Finite Plate, Yizhou Chen

Journal of Marine Science and Technology–Taiwan

In this paper, a Zener-Stroh crack problem in a finite plate is studied. By using the principle of superposition, the original problem is converted into a Zener-Stroh crack problem in an infinite plate and a usual Griffith crack problem in a finite plate. The former problem has a solution in a closed form. The latter problem can be solved by using EEVM (eigenfunction expansion variational method). Finally, numerical examples for evaluating the stress intensity factors at crack tips are presented.

Flexural Behavior And Size Effect Of Full Scale Reinforced Lightweight Concrete Beam, Chung-Hao Wu, Yu-Cheng Kan, Chung-Ho Huang, Tsong Yen, Li-Huai Chen

Journal of Marine Science and Technology–Taiwan

This article presents the results of experimental investigations on the size effect and the flexural behavior of full size reinforced concrete beams with lightweight aggregate and normal aggregate. The lightweight aggregate (LWA) was manufactured with fine sediments collected from the Shih-Men Reservoir in Taiwan. A total of 6 flexure beams with various reinforcement ratios (from 0.33% to 1.3%) and 6 size-effect beams with various dimensions were fabricated and tested. The designed compressive strength of concrete was 34 MPa. Test results indicated that the reinforced lightweight aggregate concrete (LWAC) beams had a similar load capacity and failure mode as those of …

Penetration Lag Of Chloride Diffusion Through Concrete Plate Based On Advancing Model, Chih-Hsing Wang, Cho-Liang Tsai, Ching-Chang Lin

Journal of Marine Science and Technology–Taiwan

The solution, based on Neumann's theory, for the content distribution of a diffusion material in a semi-infinite medium is applicable for the case in which a diffusion material diffuses from one side of a plate medium to the other side. After the diffusion material reaches the other side, the penetration rate of the diffusion material is solved using Fick's diffusion law. In this study, concrete plates are manufactured and submerged individually in special containers with saltwater on one side and freshwater on the other side, and no electric charge is applied. The amount of chloride penetrating the plate is monitored. …

Deformation Of Rolling Shutters Under Uniform Wind Pressure, Nan-Nong Huang, San-Ming Chang

Journal of Marine Science and Technology–Taiwan

In this study, a model is developed to analyze the structural behaviors of rolling shutters subjected to wind pressure. In the current shutter theory, the elastic properties of shutters are characterized by two bending rigidities, which can be determined from the flexural tests of slats and shutters. Close form solutions can be obtained for the deflection of shutters with two opposite simply supported edges. To assess the validity of the present theory, rolling shutters with various sizes and supporting conditions under various magnitudes of loadings are tested. It is noted that the deflections and axial displacements based on the current …

Biodeterioration Of Coastal Concrete Structures By Macro Algae - Ulva Fasciata, Stri Hari Babu Jayakumar, Rama Saravanane, Thirumalai Sundararajan

Journal of Marine Science and Technology–Taiwan

Puducherry is a coastal region in India where the growth of Ulva fasciata (Delile) is very abundant on all marine structures. Though the detrimental effect of this macro algae U. fasciata is a secondary one, its effect has to be investigated. To know its effect, the basic mechanism by which U. fasciata deteriorates concrete structures has been highlighted. To ascertain its detrimental effect on coastal concrete structures, M20 grade concrete cubes were casted and immersed in the coastal area where there is abundant growth of U. fasciata. In addition laboratory simulation has been carried out. Concrete samples collected from the …

Numerical Assessment Of Two-Chamber Mufflers With Perforated Plug/Non-Plug Tubes Under Space And Back Pressure Constraints Using Simulated Annealing, Min-Chie Chiu, Ying-Chun Chang

Journal of Marine Science and Technology–Taiwan

Recently, research on new techniques of single-chamber mufflers equipped with perforated tubes has been addressed. However, research work on shape optimization of multichamber silencers hybridized with perforated plug/non-plug tubes along with work on the maximal allowable back pressure of mufflers has been neglected. Therefore, we will not only analyze the sound transmission loss (STL) of a spaceconstrained two-chamber muffler hybridized with perforated plug/non-plug tubes but also optimize the best design shape under a specified pressure drop. In this paper, both the numerical decoupling technique and simulated annealing (SA) for solving the coupled acoustical problem of perforated plug/ non-plug tubes are …

Quantitative And Visualized Interpretation Of Public Works Civil Litigation Scenario Of First Instance Review In Taiwan, Hsien-Sang Wu, John Chien-Chung Li, Jeng-Rong Lee, Wen-Yen Wu

Journal of Marine Science and Technology–Taiwan

Existing studies regarding public works disputes and claims have drawn on small-scale cases to the exclusion of other cases and few have met the requirements of statistical tests. This paper performs an investigation of a total of 400 cases of civil litigation in which owners lost their disputes in Taiwan High Courts and branches between 1999 and 2008. Category analysis coding is used to construct a Log-linear model for judgment decisions; this model is augmented by Multiple Correspondence Analysis to reduce judicial opinions of over 4 million words to a two-dimensional figure, allowing for visual interpretation and identifying specific cases …

Comparison Between Characteristics Of Geomorphoclimatic Instantaneous Unit Hydrograph Be Produced By Gciuh Based Clark Model And Clark Iuh Model, Arash Adib, Meysam Salarijazi, Mohammad Mahmoodian Shooshtari, Ali Mohammad Akhondali

Journal of Marine Science and Technology–Taiwan

A great number of developing countries do not have sufficient rainfall-rainoff data of watersheds. For designing a hydraullic structure, considering the basic characteristics of synthetic unit hydrograph is quite indispensable. The geomorphoclimatic approach considers the rainfall and the properties of the watershed. This method can provide a better representation of the runoff estimation. In this study, a geomorphoclimatic instantaneous unit hydrograph (GcIUH) model has been developed. It’s derived from the parameters of the CLARK instantaneous unit hydrograph(IUH) which completes its shape. GcIUH based Clark model was applied from the Kasilian watershed in northern part of Iran. The Direct Surface Run …

Evaluation Of Side Resistance Capacity For Drilled Shafts, Yit-Jin Chen, Shiu-Shin Lin, Hsin-Wen Chang, Maria Cecilia Marcos

Journal of Marine Science and Technology–Taiwan

This paper presents an extensive evaluation of axial side resistance of drilled shaft foundations. A wide variety of load test data are used and these data are divided into drained and undrained databases. Representative analytical models, including alpha (α), beta (β), and lambda (λ) methods, are examined in detail using both measured and predicted results to assess their relative merits for the drilled shaft design. Based on these analyses, the undrained shear strength (α-su) correlations have exhibited better statistics for undrained side resistance prediction, and the undrained strength ratio (α-USR) correlations can be adopted as an alternative analytical method, especially …

Numerical Study On Random Waves And Wave-Induced Long-Shore Currents At Leadbetter Beach, Lei Cui, Jun Tang

Journal of Marine Science and Technology–Taiwan

Shallow coastal zone is extremely dynamic region, where the hydrodynamics are complicated as evident in the refraction, diffraction, shoaling and breaking of water waves, as well as the presence of wave-induced near-shore currents. In this paper, the distribution of waves and wave-induced long-shore currents formed by the breaking of obliquely incident random waves at Leadbetter Beach, Santa Barbara, USA are numerically studied. In the present numerical models, the random water waves are simulated based on the parabolic mild slope equation, and so the wave radiation stresses exerted on waveinduced currents are calculated based on variables in the parabolic mild slope …

Numerical Investigation Of Damping Effects On Coupled Heave And Pitch Motion Of An Innovative Deep Draft Multi-Spar, Bin-Bin Li, Jin-Ping Ou, Bin Teng

Journal of Marine Science and Technology–Taiwan

Deep draft multi-spar (DDMS), a novel deepwater platform, possesses the similar hydrodynamic and motion performances with the Spar platform. Therefore the DDMS may have instability of Mathieu’s type because the heave natural period is close to the half pitch natural period. The objective of this paper is to numerically study the damping effects on the Mathieu instability and the mechanism of this singular phenomena. In this simulation, the damping is determined through the free-decay tests based on a rigorous coupled hull and mooring model. The nonlinear motion equations of coupled heave and pitch considering the time-varying restoring forces are established …

Assessment Of Public Perception Of User-Based Fees And Tolls To Finance Transportation Infrastructure Improvements, Anurag Pande, Cornelius Nuworsoo, Adrianna Jordan, Reuben Juster, Carmeron Hunter Shew, Joe Yu

Civil and Environmental Engineering

With aging infrastructure and declining purchasing power of tax receipts new mechanisms of financing transportation alternatives are gaining increasing interest. Fuel taxes are and have been for some time the primary source of transportation finance in United States. Fuel taxes are fixed amounts that rarely change and which lose purchasing power over time as prices escalate. In addition, improvements in fuel economy can further erode the revenue stream from the gas tax. This study explores the public’s attitude about user based fees collected through tolls that are directed at specific infrastructure projects using the Inland Empire region of California as …

Proceedings, Msvscc 2011, Old Dominion University, Department Of Modeling, Simulation & Visualization Engineering, Old Dominion University, Virginia Modeling, Analysis & Simulation Center

Modeling, Simulation and Visualization Student Capstone Conference

Proceedings of the 5th Annual Modeling, Simulation & Visualization Student Capstone Conference held on April 14, 2011 at VMASC in Suffolk, Virginia. 186 pp.

Decomposition Of Unitary Matrices For Finding Quantum Circuits: Application To Molecular Hamiltonians, Anmer Daskin, Sabre Kais

Birck and NCN Publications

Constructing appropriate unitary matrix operators for new quantum algorithms and finding the minimum cost gate sequences for the implementation of these unitary operators is of fundamental importance in the field of quantum information and quantum computation. Evolution of quantum circuits faces two major challenges: complex and huge search space and the high costs of simulating quantum circuits on classical computers. Here, we use the group leaders optimization algorithm to decompose a given unitary matrix into a proper-minimum cost quantum gate sequence. We test the method on the known decompositions of Toffoli gate, the amplification step of the Grover search algorithm, …

Electric Motor & Power Source Selection For Small Aircraft Propulsion, Jeremy Fehrenbacher, David L. Stanley, Mary E. Johnson Dr., Jeffrey Honchell

Purdue Polytechnic Directed Projects

The research conducted in this project is on electrical propulsion in aviation. A Cessna 172K aircraft with a Lycoming O-320-E2D piston engine serves as a baseline measurement. Investigation of the components required for electrical flight is performed, and components are selected based on market availability and operational performance criteria.

This research focuses on electrical propulsion in the aviation industry, and is tailored to aircraft within the General Aviation sector leading to the following research question: Can current electric motor and battery technologies conceptually support flight operations for a Cessna 172K in terms of aircraft performance criteria?

The results explore the …

Mechatronics Application To Solar Tracking, Danny L. Rodriguez Jr

Purdue Polytechnic Directed Projects

The purpose of this was to design and implement a two-axis solar tracking system utilizing the National Instruments C-Rio real time controller. In order to accomplish this a prototype was modeled in CAD. This prototype used two 12 V DC motors to change a solar panel's rotation and tilt based on feedback data from three cadmium sulfide photoresistors. This configuration was chosen for its ability to create both a left-right rotational and an up/down tilt differential. In Addition this approach uses National Instruments Labview to control a solar tracking system. Using Labview add uniqueness to this project by adding a …

Offline Optimization Of Advance Reservation Of Bandwidth Over Dynamic Circuit Networks, Pragatheeswaran Angu

School of Computing: Dissertations, Theses, and Student Research

E-science projects require very high-speed and reliable networks to transfer data across various destinations in the world. Dynamic Circuit Network (DCN) is a networking service to make advance reservation of bandwidth between a source and a destination in a network. In this thesis we solve the problem of advance reservation of bandwidth in next-generation wavelength-division multiplexing (WDM) networks using a simulation based approach.
We implement a greedy algorithm and a genetic algorithm in parallel, in separate threads. The request for advance reservation is processed by both but the user gets the response only from the greedy algorithm. The genetic algorithm …

Partnership For International Research And Education In Microfluidic Technology With Applications In Point Of Care Diagnostic, Mohammed Faghri, Sigrid Berka, John Grandin, Thomas Mather, D.M.L Meyer, Zongqin Zhang, Otto Gregory, Stephan Grilli, Christopher Baxter, Constantine Anagnostopoulos, Assem Abolmaaty

Discovery@URI

This poster summarizes the research highlights of a project conducted as part of an National Science Foundation (NSF) partnership for research and education. The objective of this multidisciplinary, international project was to conduct research on microfluidic technology and applications. The project team is comprised of participants from the University of Rhode Island and the Technical University of Braunschweig in Germany. The research focuses on the following four tasks: Task 1 – Discovery of disease biomarkers; Task 2 –Streaming based microfluidic platform for pumping, mixing, separation and detection; Task 3 – Development of rapid, quantitative and sensitive microfluidic fluorescence immunosensors for …

My Adventures In Helicopters!, Dwayne Williams

ERAU Prescott Aviation History Program

Hear the remarkable story of a lifetime flying helicopters, from a flight test pilot for Bell, Heritage Aviation Ltd. and MD helicopters.

Development Of High Resolution Sea Floor Mapping Tools And Techniques, Gabrielle Inglis, J. Ian Vaughn, Clara Smart, Christopher N. Roman

Graduate School of Oceanography Faculty Publications

There is a persistent need for high resolution photographic and bathymetric maps of the sea floor for many research areas in marine geology, biology and archaeology. This poster will present recent work using high frequency multibeam sonars, stereo vision and structured light laser imaging techniques to create maps with centimeter resolution for these applications. This research involves the development of new image and sonar processing techniques that combat the typical difficulties of imperfect navigation information, limited sensor ranges and adverse environmental conditions associated with using marine robotic vehicles in the ocean. Data for this work has been collected with the …

Arra Advanced Weatherization Training Center - Quarterly Report (January 2011-March 2011), Florida Solar Energy Center, Neil Moyer

FSEC Energy Research Center®

The 1st quarter of 2011 was the beginning of procurement for the training center. Two pieces of equipment, the insulation blowing machine and infrared cameras, were put out for quotes. Both have been selected and purchase orders created.

Evaluating Impact Attenuator Performance For A Formula Sae Vehicle, Jason Fahland, Craig Hoff, Janet Brelin-Fornari

Crash Safety Center Publications

Formula SAE® is one of several student design competitions organized by SAE International. In the Formula SAE events undergraduate and graduate students are required to conceive, design, fabricate and compete with a small, formula-style, race car. Formula SAE safety rules dictate a 7 m/s (or approximately 15.65 mph) frontal crash test for nose mounted impact attenuators. These rules are outlined in section B3.21 of the Formula SAE rule book. Development and testing methods of these energy absorbing devices have varied widely among teams. This paper uses real world crash sled results to research methods for predicting the performance of aluminum …

Effect Of Gold Content On The Reliability Of Snagcu Solder Joints, Jianbiao Pan, Julie Silk, Mike Powers, Patrick Hyland

Industrial and Manufacturing Engineering

Electroplated Ni/Au over Cu is a popular metallization for PCB finish as well as for component leads, especially wire-bondable high frequency packages, where the gold thickness requirement for wirebonding is high. The general understanding is that less than 3 wt% of Au is acceptable in SnPb solder joints. However, little is known about the effect of Au content on the reliability of SnAgCu solder joints. The purpose of this study is to determine the acceptable level of Au in SAC305 solder joints. Three different package platforms with different Au thicknesses were assembled on boards with two different Au thicknesses using …

Evaluating Impact Attenuator Performance For A Formula Sae Vehicle, Jason Fahland, Craig Hoff, Janet Brelin-Fornari

Mechanical Engineering Publications

Formula SAE® is one of several student design competitions organized by SAE International. In the Formula SAE events undergraduate and graduate students are required to conceive, design, fabricate and compete with a small, formula-style, race car. Formula SAE safety rules dictate a 7 m/s (or approximately 15.65 mph) frontal crash test for nose mounted impact attenuators. These rules are outlined in section B3.21 of the Formula SAE rule book. Development and testing methods of these energy absorbing devices have varied widely among teams. This paper uses real world crash sled results to research methods for predicting the performance of aluminum …

Mitochondrial Approaches To Protect Against Cardiac Ischemia And Reperfusion Injury, Amadou K.S. Camara, Martin Bienengraeber, David F. Stowe

Biomedical Engineering Faculty Research and Publications

The mitochondrion is a vital component in cellular energy metabolism and intracellular signaling processes. Mitochondria are involved in a myriad of complex signaling cascades regulating cell death vs. survival. Importantly, mitochondrial dysfunction and the resulting oxidative and nitrosative stress are central in the pathogenesis of numerous human maladies including cardiovascular diseases, neurodegenerative diseases, diabetes, and retinal diseases, many of which are related. This review will examine the emerging understanding of the role of mitochondria in the etiology and progression of cardiovascular diseases and will explore potential therapeutic benefits of targeting the organelle in attenuating the disease process. Indeed, recent advances …

Fluxes Across Double-Diffusive Interfaces: A One-Dimensional-Turbulence Study, Esteban Gonzalez-Juez, Alan R. Kerstein, David O. Lignell

Faculty Publications

This work is a parametric study of the fluxes of heat and salt across unsheared and sheared double-diffusive interfaces using one-dimensional-turbulence (ODT) simulations. It is motivated by the need to understand how these fluxes scale with parameters related to the fluid molecular properties and background shear. Comparisons are made throughout with previous models and available measurements. In unsheared interfaces, ODT simulations show that the dimensionless heat flux Nu scales with the stability parameter Rρ, Rayleigh number Ra and Prandtl number Pr as Nu ~ (Ra/Rρ)0.37±0.03 when Pr varies from 3 to 100 and as Nu ~ (Ra/Rρ)0.31Pr0.22±0.04 when Pr varies …

An Analysis Of Analytical Methods To Produce A Varying Angular Output From A Constant Angular Input Using Gearsets, Isaac R. Jones

Theses and Dissertations

Research in developing a Positively Engaged Continuously Variable Transmission (PECVT) has been underway at Brigham Young University for some time. The inherent problems associated with embodiments of this type of transmission, namely the Non-Integer Tooth Problem (NITP), have been identified. This research is focused on the development of a Positively Engaged Piecewise Continuous Transmission (PEPCT), which is a subset of the PECVT. This document describes the hypothesis and analysis of using non-circular gearsets to overcome the NITP. This proposed solution enables a varying angular output from a constant angular input. In this research two analytical methods were evaluated based on …

Evaluation Of Transient Refrigerant Migration Modeling Approach On Automotive Air Conditioning Systems, Bin Li, Steffen Peuker, Pega Hrnjak, Andrew Alleyne

Mechanical Engineering

Automotive air conditioning systems are subject to constantly changing operation conditions and steady state simulations are not sufficient to describe the actual performance. The refrigerant mass migration during transient events such as clutch-cycling or start-up bas a direct impact on the transient performance. It is therefore necessary to develop simulation tools which can accurately predict the migration of the rerrigerant mass. To this end a dynamic model of an automotive air conditioning system is presented in this paper using a switched modeling framework. Model validation against experimental results demonstrates that the developed modeling approach is able to describe the transient …

Strain Monitoring Of Carbon Fiber Composite With Embedded Nickel Nano-Composite Strain Gage, Timothy Michael Johnson

Theses and Dissertations

Carbon fiber reinforced plastic (CFRP) composites have extensive value in the aerospace, defense, sporting goods, and high performance automobile industries. These composites have huge benefits including high strength to weight ratios and the ability to tailor their properties. A significant issue with carbon fiber composites is the potential for catastrophic fatigue failure. To better understand this fatigue, there is first a huge push to measure strain accurately and in-situ to monitor carbon fiber composites. In this paper, piezoresistive nickel nanostrand (NiNs) nanocomposites were embedded in between layers of carbon fiber composite for real time, in situ strain monitoring. Several different …