Engineering Commons^™

Uhtc Composites: Processing, Performance And Future, Jon Binner

Ultra-High Temperature Ceramics: Materials for Extreme Environment Applications III

No abstract provided.

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering: News & Publications (2013-2023)

• Eagle Motorspots Places 5th Overall at Auburn

Diffusion In A Solid Cylinder Part I: Advancing Model, Cho-Liang Tsai, Ching-Chang Lin

Journal of Marine Science and Technology–Taiwan

An advanced diffusion model is used to calculate the concentration of a substance diffused in a solid cylindrical medium. The mathematical process in this study adopts Neumann’s algorithm for applying the advancing model to revise the solution derived by Carslaw and Jaeger. The modified solution clearly indicates a diffusion front which does not exist in the original model. Calculating the diffusion depth becomes possible and is novel for a solid cylindrical medium. The major contribution of this study is the application of the advancing model to solve the diffusion problem of a cylindrical medium in cylindrical coordinate system.

A Blackboard-Style Decision-Making System For Multi-Tier Craft Control And Its Evaluation, Jeremy Straub, Hassan Reza

Computer Science Faculty Publications

This article presents an approach for decision-making in support of the control of an autonomous system of multiple tiers of robots (e.g., satellite, aerial and ground) based on the Blackboard architectural style. Under the proposed approach, the system evaluates prospective approaches for goal satisfaction (identified by user selected final rules), identifies the lowest-cost solution and determines the best path to achieving the goal, via the analysis of the Blackboard rule and action set. Two different approaches to this rule and action path generation are discussed. This article presents the proposed Blackboard-style architecture for autonomous multi-tier control and describes its implementation. …

A Linearly Constrained Signal Subspace Projection Approach Developed To Detect Targets In Hyperspectral Images, Zay-Shing Tang, Lena Chang, Hsien-Sen Hung

Journal of Marine Science and Technology–Taiwan

Hyperspectral images have been widely used for target detection. In general, target signatures should be known a priori for filter-based detection methods. However, the uncertainty of target signatures caused by the influence of atmospheric interference or other random noise degrades the detection performance. Therefore, developing a robust detection method is crucial in hyperspectral image analysis. In this study, a linearly constrained signal subspace projection approach for target detection is proposed. Instead of using a single constraint on target detection, an optimal filter with multiple constraints is designed using signal subspace projection (SSP). The SSP approach fully exploits the orthogonal property …

Voltage Sag Planning Of A Power System With Specially Connected Transformers Using Hybrid Differential Evolution Considering Iti Curve, Yao-Hung Chan, Chi-Jui Wu, Ying-Pin Chang

Journal of Marine Science and Technology–Taiwan

This paper outlines the voltage sag planning of a power system with a three-phase to two-phase transformer. We compared systems with V-V and Scott connection schemes using the hybrid differential evolution (HDE) method to determine the design parameters by taking into account the ITI curves and coordination of over-current relays. The proposed model comprises a node admittance matrix for the calculation of voltage sag in order to determine the severity of system sag after single or two-phase faults. These analytical equations are useful in the mathematical determination of optimal design parameters. We also used the proposed method to obtain suitable …

Experimental Study Of Seismic Performances Of Rc Bridge Columns With Cfst Column Embedded Lnside, Wen-Liang Qiu, Chin-Sheng Kao, Chang-Huan Kou, Jeng-Lin Tsai

Journal of Marine Science and Technology–Taiwan

To improve the seismic performances of reinforced concrete (RC) bridge columns and to prevent columns from shear failure and core concrete crushing, high strength concrete filled steel tube (CFST) is put into RC columns to form a new kind of composite column. Through cyclical loading tests, the seismic performances of four columns are studied. The first column tested is a conventional RC column, the second one is a bonded composite column, the third one is an unbonded composite column, and the fourth one is an unbonded composite column whose axial force is composed of only bone by its CFST column. …

An O(T2) Boundary Layer In Sliding Mode For Time-Delay Systems, Ming-Chang Pai

Journal of Marine Science and Technology–Taiwan

A new discrete-time integral sliding mode control scheme is proposed for a class of linear multi-input systems with state delays. Based on the Lyapunov stability theory and one-step delayed disturbance approximation, a sliding mode controller not only drives the sliding mode into the O(T2 ) boundary, but also achieves the O(T2 ) boundary for state regulation. A novel integral sliding surface is introduced so that reaching phase is eliminated. Chattering phenomenon is eliminated and the knowledge of upper bound of external disturbances is not required. The validity of the proposed control methodology is demonstrated by simulation results.

Flavour Chemicals In Electronic Cigarette Fluids, Peyton A. Tierney, Clarissa D. Karpinski, Jessica E. Brown, Wentai Luo, James F. Pankow

Chemistry Faculty Publications and Presentations

Background: Most e-cigarette liquids contain flavour chemicals. Flavour chemicals certified as safe for ingestion by the Flavor Extracts Manufacturers Association may not be safe for use in e-cigarettes. This study identified and measured flavour chemicals in 30 e-cigarette fluids.

Methods: Two brands of single-use e-cigarettes were selected and their fluids in multiple flavour types analysed by gas chromatography/mass spectrometry. For the same flavour types, and for selected confectionary flavours (eg, bubble gum and cotton candy), also analysed were convenience samples of e-cigarette fluids in refill bottles from local ‘vape’ shops and online retailers.

Results: In many liquids, total flavour chemicals …

Numerical Simulation Of Water Entry Of Wedges Based On The Cip Method, Zhao-Yu Wei, He-Ye Xiao, Zhi-Dong Wang, Xiu-Hua Shi

Journal of Marine Science and Technology–Taiwan

The hydrodynamic problems for water entry of wedges are studied by a constrained interpolation profile (CIP) based on Cartesian grid method. The CIP scheme was applied to the Cartesian grid based on flow solver, which was first described. The tangent of hyperbola for interface capturing (THINC) scheme was applied to capture the free surface. The CIP method was extended to capture the dynamics in the water entry approach. The simulations were performed in three aspects. First, pressure distributions for the wedges entering into water with constant speed were predicted, and the results were compared with the similarity solutions by the …

Robust Bearing Estimation In Shallow Water Using Vector Optimization, Hai-Yan Song, Jie Shi, Chang-Yi Yang, Bo-Sheng Liu, Ming Diao

Journal of Marine Science and Technology–Taiwan

Correlated multi-paths may cause a biased bearing estimation in shallow water, so most existing methods make fully use of the multi-path nature and the underwater channel property to provide an unbiased bearing estimation. However, an imprecise knowledge of the underwater channel parameters or the array model mismatches will cause performance degradation, especially for the high-resolution methods. Therefore development of robust bearing estimation methods in shallow water is critically important. In this paper, a new approach to robust bearing estimation is proposed in the presence of underwater channel parameter uncertainties or array model mismatches. The proposed method is based on the …

Solving The Inverse Cauchy Problem Of The Laplace Equation Using The Method Of Fundamental Solutions And The Exponentially Convergent Scalar Homotopy Algorithm (Ecsha), Weichung Yeih, I-Yao Chan, Cheng-Yu Ku, Chia-Ming Fan

Journal of Marine Science and Technology–Taiwan

In this paper, the inverse Cauchy problem of the Laplace equation is considered. Using the method of fundamental solutions, a system of linear algebraic equations can be obtained by satisfying the Cauchy boundary conditions on the overprescribe boundary points. The resulting linear algebraic equation is ill-posed and is treated by the exponentially convergent scalar homotopy algorithm (ECSHA). Four examples are adopted to show the validity of the proposed numerical scheme and it is concluded that the current approach can successfully resolve the ill-posedness of the inverse Cauchy problem even when the noise exists.

Nonlinear Breaker Characteristics And Impulse On A Sloping Bottom, Wen-Jer Tseng

Journal of Marine Science and Technology–Taiwan

This paper presents an experimental and theoretical investigation of nonlinear surface-wave propagation over a sloping bed. First, a second-order analytical solution for nonlinear surface-wave propagation over a sloping bed is derived using a perturbation method for the bottom slope  and the wave steepness  in an Eulerian system. Then, by transforming the flow field solution from an Eulerian system into a Lagrangian system, more accurate wave profiles are determined. New theoretical breaker characteristics and breaker impulses are derived using the kinematic stability parameter. Subsequently, a series of experiments to measure breaker characteristics and the breaker impulse are conducted in …

Effects Of The Cathodic Current On Alkali-Silica Aggregate Reaction, Jiang-Jhy Chang, Weichung Yeih, Cheng-Chin Chang

Journal of Marine Science and Technology–Taiwan

In this study, we investigated whether the cathodic current accelerates the alkali-silica aggregate reaction. Variables considered were the water/cement (w/c) ratio, initial alkali content, and cathodic current. The crack initiation time, crack mouth opening history, and microhardness values were monitored to examine the effect of the cathodic current on crack initiation and propagation due to the alkali-silica aggregate reaction. In addition, chemical titration was performed to determine the amount of accumulated sodium and potassium ions to support our viewpoints. The results showed that the crack initiation time shortened with an increase in the initial alkali content, w/c ratio, and/or cathodic …

Design And Simulation Of A C-Band Pyramidal Horn Antenna For Water-Level Radar Sensors, Ke-Ru Chou, Tzong-Dar Wu, Han-Nien Lin, Tai-Shan Liao, Kwong-Kau Tiong

Journal of Marine Science and Technology–Taiwan

A prototype C-band pyramidal horn antenna was fabricated after using High Frequency Structure Simulator (HFSS) software to simulate, analyze, and optimize the design parameters. The pyramidal horn antenna was designed to operate as a key detection component for disaster prevention and warning instruments in the domestic development of water-level radar sensor (WLRS). Experimental measurements showed the horn operating with a bandwidth of ~ 800 MHz from 5.4 GHz to 6.2 GHz with the central frequency at 5.8 GHz. The voltage standing wave ratio (VSWR) in the operating frequency range and the radiation pattern gains were measured to be smaller than …

Fuzzy Assessment On Reservoir Water Quality, Ruey-Tyng Lin, Wen-Cheng Huang

Journal of Marine Science and Technology–Taiwan

Carlson's Trophic State Index (CTSI) has long been used in the Taiwan region to assess reservoir eutrophication, however this approach can often lead to confusion because the assessment criteria for CTSI (such as Secchi disk Depth) can be degraded by factors such as turbidity, which does not actually reflect the increased eutrophication. Mountainous subtropical islands suffer from serious stormdriven erosion problems, leaving reservoir water quality subject to seasonal weather conditions, torrential rains, typhoons and turbidity. Thus the CTSI alone may be insufficient or inappropriate at certain times to evaluate water quality. In pratice, we found that this indicator could produce …

Swosu Research And Scholarly Activity Fair 2015, Jason L. Johnson

SWOSU Research and Scholarly Activity Fair Programs

Welcome to the Twenty-Second SWOSU Research and Scholarly Activity Fair! On display today are 103 presentations involving 169 student researchers, writers, performers, and artists, and 40 faculty sponsors encompassing scholarly activity from the Departments of: Accounting, Computer Science, and Entrepreneurship; Art, Communication, and Theatre; Biological Sciences; Chemistry and Physics; Education; Engineering Technology; Finance, Management, and Marketing; Language and Literature; Music; Nursing and Allied Health; Pharmaceutical Sciences; Psychology; and Social Sciences.

Characterization Of Ultra High Temperature Ceramic Coatings Deposited By Vacuum Plasma Spraying, Diletta Sciti, Yeon Woo Yoo, Sea Hoon Lee

Ultra-High Temperature Ceramics: Materials for Extreme Environment Applications III

No abstract provided.

College Of Engineering News, Georgia Southern University

College of Engineering & Computing: News & Publications (2010-2023)

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Monolayer And/Or Few-Layer Graphene On Metal Or Metal-Coated Substrates, Peter Werner Sutter, Eli Anguelova Sutter

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed is monolayer and/or few-layer graphene on metal or metal-coated substrates. Embodiments include graphene mirrors. In an example, a mirror includes a substrate that has a surface exhibiting a curvature operable to focus an incident beam onto a focal plane. A graphene layer conformally adheres to the substrate, and is operable to protect the substrate surface from degradation due to the incident beam and ambient environment.

A Study Of Microwave Curing Of Underfill Using Open And Closed Microwave Ovens, Aditya Thakare

Dissertations and Theses

As the demand for microprocessors is increasing with more and more consumers using integrated circuits in their daily life, the demand on the industry is increasing to ramp up production.

In order to speed up the manufacturing processes, new and novel approaches are trying to change certain aspects of it. Microwaves have been tried as an alternative to conventional ovens in the curing of the polymers used as underfills and encapsulants in integrated circuits packages. Microwaves however being electromagnetic waves have non uniform energy distribution in different settings, causing burning or incomplete cure of polymers.

In this study, we compare …

Ultra-High Temperature Mechanical Properties Of Zirconium Diboride-Based Ceramics, W.G. Fahrenholtz, G.E: Hilmas

Ultra-High Temperature Ceramics: Materials for Extreme Environment Applications III

No abstract provided.

Sustained Hypersonic Flight – It’S Harder Than Rocket Science, Michael Smart

Ultra-High Temperature Ceramics: Materials for Extreme Environment Applications III

No abstract provided.

Processing And Characterisation Of (Ta,Hf)C Ultra-High Temperature Ceramics., O. Cedillos, S. Grasso, D. Manara, D.D Jayaseelan, R. Konings, W.E. Lee

Ultra-High Temperature Ceramics: Materials for Extreme Environment Applications III

No abstract provided.

Synthesis And Static Oxidation Testing Of Doped Hfb2 Powders, Pengxiang Zheng, Jon Binner, Bala Vaidhyanathan

Ultra-High Temperature Ceramics: Materials for Extreme Environment Applications III

No abstract provided.

Green Polymer Chemistry: Investigating The Mechanism Of Radical Ring-Opening Redox Polymerization (R3p) Of 3,6-Dioxa-1,8-Octanedithiol (Dodt), Emily Q. Rosenthal-Kim, Judit E. Puskas

Chemical, Biomolecular, and Corrosion Engineering Faculty Research

The mechanism of the new Radical Ring-opening Redox Polymerization (R3P) of 3,6-dioxa-1,8-octanedithiol (DODT) by triethylamine (TEA) and dilute H₂O₂ was investigated. Scouting studies showed that the formation of high molecular weight polymers required a 1:2 molar ratio of DODT to TEA and of DODT to H₂O₂. Further investigation into the chemical composition of the organic and aqueous phases by ¹H-NMR spectroscopy and mass spectrometry demonstrated that DODT is ionized by two TEA molecules (one for each thiol group) and thus transferred into the aqueous phase. The organic phase was found …

Optimization Of Operational Costs In Data Centers, Shaoming Chen

LSU Master's Theses

The electricity cost of cloud computing data centers dominated by server power and cooling power is growing rapidly. To tackle this problem, inlet air with moderate temperature and server consolidation are widely adopted. However, the benefit of these two methods is limited due to conventional air cooling systems ineffectiveness caused by re-circulation and low heat capacity. To address this problem, hybrid air and liquid cooling, as a practical and inexpensive approach, has been introduced. In this work, we quantitatively analyze the impact of server consolidation and temperature of cooling water on the total electricity and server maintenance costs in hybrid …

On The Influence Of Ionic Strength On Radium And Strontium Sorption To Sandy Loam Soils, Brian A. Powell, Todd Miller, Daniel I. Kaplan

Journal of the South Carolina Academy of Science

Models which can estimate environmental transport of radioactive contaminants in natural and engineered systems are required to 1) deploy effective remediation strategies for contaminated sites, 2) design waste repositories for future waste streams, and 3) ensure protection of human and environmental health in all cases. These models require accurate transport parameters in order to correctly predict how these contaminants will move in the subsurface. This work aimed to determine more accurately the distribution coefficients for radium and strontium sorption to Savannah River Site (SRS) soils. Radium and strontium sorption to the soils was found to be highly dependent upon ionic …

Towards The Perfect Optical Fiber, John Ballato

Journal of the South Carolina Academy of Science

Optical fibers are being used in an ever more diverse array of applications today. Many of these modern applications are in high-power and, particularly, high power-per-unit-bandwidth systems where optical nonlinearities historically have not limited overall performance. Today, however, nominally weak effects, such as stimulated Brillouin scattering (SBS), are restricting continued scaling to higher optical powers. To address these limitations, the optical fiber industry has focused on fiber geometry-related solutions such as large mode area (LMA) designs. However, since all linear and nonlinear optical phenomena are fundamentally materials-based in origin, this paper identifies material solutions to present and future performance limitations …

Preface, George Franks, Carolina Tallon

Ultra-High Temperature Ceramics: Materials for Extreme Environment Applications III

No abstract provided.