Engineering Commons^™

Surface Feature Engineering Through Nanosphere Lithography, Tod V. Laurvick, Ronald A. Coutu Jr., James M. Sattler, Robert A. Lake

Faculty Publications

How surface geometries can be selectively manipulated through nanosphere lithography (NSL) is discussed. Self-assembled monolayers and multilayers of nanospheres have been studied for decades and have been applied to lithography for almost as long. When compared to the most modern, state-of-the-art techniques, NSL offers comparable feature resolution with many advantages over competing technologies.

Designing And Building An Automatic Chamfer Grinder, William Johnson

Mahurin Honors College Capstone Experience/Thesis Projects

Modern day manufacturing is a demanding environment with a constant need for process improvement. As automation becomes more advanced, there are fewer jobs that must be completed by a human. In the case of Stupp Bridge Company, a local manufacturer of steel bridge girders, their workforce is highly skilled, so replacing mundane tasks with automation allow the skilled workers to focus on the difficult jobs. One such task is grinding a chamfer onto every leading edge of each girder flange, eight edges in total, ranging from 20 to 200 feet long. The purpose of this project was to design an …

On Event-Triggered Adaptive Architectures For Decentralized And Distributed Control Of Large-Scale Modular Systems, Ali Albattat, Benjamin C. Gruenwald, Tansel Yucelen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The last decade has witnessed an increased interest in physical systems controlled over wireless networks (networked control systems). These systems allow the computation of control signals via processors that are not attached to the physical systems, and the feedback loops are closed over wireless networks. The contribution of this paper is to design and analyze event-triggered decentralized and distributed adaptive control architectures for uncertain networked large-scale modular systems; that is, systems consist of physically interconnected modules controlled over wireless networks. Specifically, the proposed adaptive architectures guarantee overall system stability while reducing wireless network utilization and achieving a given system performance …

Handcrafted Electrocorticography Electrodes For A Rodent Behavioral Model, Nishat Tasnim, Ali Ajam, Raul Ramos, Mukhesh K. Koripalli, Manisankar Chennamsetti, Yoonsu Choi

Electrical and Computer Engineering Faculty Publications

Electrocorticography (ECoG) is a minimally invasive neural recording method that has been extensively used for neuroscience applications. It has proven to have the potential to ease the establishment of proper links for neural interfaces that can offer disabled patients an alternative solution for their lost sensory and motor functions through the use of brain-computer interface (BCI) technology. Although many neural recording methods exist, ECoG provides a combination of stability, high spatial and temporal resolution with chronic and mobile capabilities that could make BCI systems accessible for daily applications. However, many ECoG electrodes require MEMS fabricating techniques which are accompanied by …

A Fuzzy Data Envelopment Analysis Framework For Dealing With Uncertainty Impacts Of Input–Output Life Cycle Assessment Models On Eco-Efficiency Assessment, Gokhan Egilmez, Serkan Gumus, Murat Kucukvar, Omer Tatari

Mechanical and Industrial Engineering Faculty Publications

The uncertainty in the results of input–output-based life cycle assessment models makes the sustainability performance assessment and ranking a challenging task. Therefore, introducing a new approach, fuzzy data envelopment analysis, is critical; since such a method could make it possible to integrate the uncertainty in the results of the life cycle assessment models into the decision-making for sustainability benchmarking and ranking. In this paper, a fuzzy data envelopment analysis model was coupled with an input–output-based life cycle assessment approach to perform the sustainability performance assessment of the 33 food manufacturing sectors in the United States. Seven environmental impact categories were …

Gpu-Arraysort: A Parallel, In-Place Algorithm For Sorting Large Number Of Arrays, Muaaz Awan, Fahad Saeed

Parallel Computing and Data Science Lab Technical Reports

Modern day analytics deals with big datasets from diverse fields. For many application the data is in the form of an array which consists of large number of smaller arrays. Existing techniques focus on sorting a single large array and cannot be used for sorting large number of smaller arrays in an efficient manner. Currently no such algorithm is available which can sort such large number of arrays utilizing the massively parallel architecture of GPU devices. In this paper we present a highly scalable parallel algorithm, called GPU-ArraySort, for sorting large number of arrays using a GPU. Our algorithm performs …

Shape Optimization Of Two-Chamber Mufflers Hybridized With Multiple Parallel Dissipative Tubes Using Simulated Annealing Method, Ho-Chih Cheng, Min-Chie Chiu

Journal of Marine Science and Technology–Taiwan

Mufflers hybridized with a single dissipative tube have been extensively researched; however, there has been a palpable lack of work directed toward mufflers conjugated with multiple parallel dissipative tubes that disperse venting fluid and reduce secondary noise. That being so, an analysis of the Sound Transmission Loss (STL) of two-chamber mufflers with multiple parallel dissipative tubes that are optimally designed to perform within a limited space will be considered, here. By using a decoupled numerical method, a four-pole system matrix for evaluating acoustic performance (STL) emerges. During the optimization process, a simulated annealing (SA) method, which is a robust scheme …

Winter Sea Fog Detection Using Trmm Microwave Measurements Over The Taiwan Strait, Nan-Ching Yeh, Wann-Jin Chen, Gin-Rong Liu, Chung-Chih Liu

Journal of Marine Science and Technology–Taiwan

The impact of fog on activities such as land transportation, flight and marine operations, and military missions can be dangerous. Thus, this study developed a new and simple method for detecting fog areas over the Taiwan Strait more accurately during winter by using the Tropical Rainfall Measuring Mission Microwave Imager (TMI) Level-1B calibrated brightness temperature (TB) data, combined with ground station fog observations. This method is based on the microwave TB differences among four TMI channels, including horizontal and vertical polarization TBs of 37.0 and 85.5 GHz, for heavy fog and clear weather conditions. The method can be applied to …

Nanoparticle Formation In The Flame Synthesis Of Multicomponent Nanostructured Materials For Clean Energy Applications, Jiaxi Fang

McKelvey School of Engineering Graduate Student Theses & Dissertations

This dissertation studies the initial stages of particle formation during the combustion synthesis of multicomponent nanomaterials. Combustion is commonly used for the production of nanomaterials at industrial scales and has advantages of high production rates, low waste generation, and scalability. However, there are limitations in being able to apply this synthesis approach to more advanced multicomponent systems. Gas to particle conversion in flames occurs through precursor decomposition, collisional growth, coagulation, condensation, and sintering. There is a fundamental gap in knowledge on the initial stages of particle formation in flames below 2nm due to measurement difficulties and instrumentation limitations. Using a …

Neural Representation Of Vocalizations In Noise In The Primary Auditory Cortex Of Marmoset Monkeys, Ruiye Ni

McKelvey School of Engineering Graduate Student Theses & Dissertations

Robust auditory perception plays a pivotal function in processing behaviorally relevant sounds, particularly when there are auditory distractions from the environment. The neuronal coding enabling this ability, however, is still not well understood. In this study we recorded single-unit activity from the primary auditory cortex of alert common marmoset monkeys (Callithrix jacchus) while delivering conspecific vocalizations degraded by two different background noises: broadband white noise (WGN) and vocalization babble (Babble).

Noise effects on single-unit neural representation of target vocalizations were quantified by measuring the response similarity elicited by natural vocalizations as a function of signal-to-noise ratio (SNR). Four consistent response …

Calcium Carbonate Formation In Energy-Related Subsurface Environments And Engineered Systems, Qingyun Li

McKelvey School of Engineering Graduate Student Theses & Dissertations

Geologic CO2 sequestration (GCS) in subsurface saline aquifers is a promising strategy to mitigate climate change caused by increasing anthropogenic CO2 emissions from energy production. At GCS sites, interactions between fluids and geomedia are important because they can affect CO2 trapping efficiency and the safety of CO2 storage. These interactions include the dissolution and precipitation of minerals. One of the most important minerals is calcium carbonate, because it can permanently trap CO2.

In this work, Portland cement was used as a model geomedium to investigate the chemical reactions, mechanical alterations, transport of reactive fluids, and the interplay of all these …

Crumpled Graphene Oxide: Aerosol Synthesis And Environmental Applications, Yi Jiang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Environmental technologies, such as for water treatment, have advanced significantly due to the rapid expansion and application of nanoscale material science and engineering. In particular, two-dimensional graphene oxide (GO), has demonstrated considerable potential for advancing and even revolutionizing some of these technologies, such as engineered photocatalysts and membranes. To realize such potential, an industrially scalable process is needed to produce monomeric and aggregation-resistant GO nanostructures/composites, in addition to new knowledge of material properties, behavior, and performance within an environmental context.

Research presented in this thesis addresses both scientific and engineering gaps through the development of a simple, yet robust aerosol-based …

Silk As A Biomaterial Paste For Biomimetic Composite, Sang Hyun Park

McKelvey School of Engineering Graduate Student Theses & Dissertations

Silk is a highly promising biomaterial with unique bio-physicochemical properties, such as excellent mechanical and optical properties, biocompatibility and programmable biodegradability. Among many different types, silk from domesticated silkworm, bombyx mori has received wide attention owing to its availability in virtually unlimited quantities and ease of extraction. In this study, we investigated silkworm silk as a protein glue to realize nacre-like composites. We have employed spin assisted layer-by-layer technique to fabricate ultrathin free-standing biocomposite films. Two different composites have been studied: (i) graphene oxide (GO)/silk and (ii) chitin/silk. From our prior work, it is known that the adsorption of amphiphilic …

Nanostructured Thin Film Synthesis By Aerosol Chemical Vapor Deposition For Energy Storage Applications, Tandeep Singh Chadha

McKelvey School of Engineering Graduate Student Theses & Dissertations

Renewable energy sources offer a viable solution to the growing energy demand while mitigating concerns for greenhouse gas emissions and climate change. This has led to a tremendous momentum towards solar and wind-based energy harvesting technologies driving efficiencies higher and costs lower. However, the intermittent nature of these energy sources necessitates energy storage technologies, which remain the Achilles heel in meeting the renewable energy goals. This dissertation focusses on two approaches for addressing the needs of energy storage: first, targeting direct solar to fuel conversion via photoelectrochemical water-splitting and second, improving the performance of current rechargeable batteries by developing new …

State Space Analysis Of Dominant Structures In Dynamic Social Systems, Jeremy B. Sato

McKelvey School of Engineering Graduate Student Theses & Dissertations

Many systems involving human relationships are modeled as dynamic systems, as diverse as urban population growth, diffusion of innovations, spread of viruses, and supply chain management. A fundamental assumption is that these systems contain variables which accumulate and deplete over time (people, innovation adoptions, infections, and orders), and whose dynamics are determined by societal rules and human decision making processes. These assumptions allow the system to be formally expressed by ordinary differential equations which are often nonlinear and contain multiple state variables and feedback loops. Analytical methods have been developed to identify the dominant feedback loops which primarily influence the …

Examining The Behaviors Of Sandy And Silty Seabed Under Wave Actions, Yuchen Wang, Erwin Oh, Jiemin Zhan

Journal of Marine Science and Technology–Taiwan

Coastal structures are always facing the threat of damage caused by different wave actions. A better understanding of different seabed behavior could effectively reduce the damage caused by waves. In this paper, a 2 Dimensional quasi-dynamic u-w-p model is developed to analyze the different behaviors of seabed composed of loose sand, dense sand and silt. In the u-w-p model, acceleration, velocity and displacement has been considered, and three important parameters: pore water pressure, effective stress and shear stress, are obtained from the model with Finite Difference Method (FDM) and applied to describe the general behavior of seabed consisting of various …

Longitudinal Surface Roughness Effects In Magnetic Fluid Lubricated Journal Bearings, Jaw-Ren Lin

Journal of Marine Science and Technology–Taiwan

According to the magnetic fluid model incorporating with the stochastic model, the performance characteristics of a magnetic fluid lubricated short journal bearing with rough surfaces are investigated. A stochastic magnetic fluid based Reynolds equation has been derived. Analytical expressions for the bearing performances are also obtained. From the results obtained, the effects of longitudinal roughness patterns result in an increased load capacity as well as a reduced friction parameter and attitude angle. The amounts of increased load and reduced friction parameter are more pronounced for the bearing operating at higher values of the volume concentration, magnetic parameter, roughness parameter and …

Dynamic Simulation Of Subsea Equipment Installation Using An Offshore Support Vessel Based On Flexible Multibody System Dynamics, Jeong-Woo Hong, Myung-Il Roh, Seung-Ho Ham, Sol Ha

Journal of Marine Science and Technology–Taiwan

An offshore support vessel (OSV) is a ship that supports exploration, development, and production activities in the offshore industry. Recently, industrial demand for OSVs has increased due to a large number of offshore field development projects worldwide. One of the main functions of an OSV is heavy lifting such as subsea equipment installations in offshore oil or gas fields using crane. Therefore, predicting dynamic loads in various operation conditions is one of the crucial points in the lifting operation of an OSV. To do this, crane-lifting simulation needs to precede real operation to verify the safety of the lifting operation. …

Chloride-Binding Isotherms In Concrete Submitted To Non-Steady-State Diffusion-Migration Model, Wen-Hu Tsao, Ming-Te Liang, Ta-Peng Chang

Journal of Marine Science and Technology–Taiwan

We propose a mathematical non-steady-state, time/depth dependent diffusion-migration model based on the modified Fick’s second law of diffusion. It considers the effects of different chloride binding mechanisms for the transport process of chloride ions diffused in a porous concrete on the variation of its chloride profile. Four different chloride-binding isotherms, i.e., no binding, linear binding, Langmuir binding and Freundlich binding, together with the time/depth dependent chloride diffusivities are investigated. Results of this study show that the variations of amounts of available free chloride ions in the solution of saturated concrete resulting from different chloride-binding isotherms have significant effects on the …

Simulation Of The Effect Of Breakwater On The Propagation Of Solitary Waves, Ching-Piao Tsai, Ying-Chi Chen, Chun-Jen Chen, Chang Lin

Journal of Marine Science and Technology–Taiwan

A numerical simulation of the effect of breakwater on the propagation of solitary waves was presented in this study using CFD based on the Reynolds-averaged Navier-Stokes (RANS) equations coupled with the renormalization group (RNG) turbulent model. The wave transformation and the flow field variation of solitary waves propagating over composite breakwaters of different heights were simulated. The effect of breakwater height on the run-up of solitary waves on the slope was discussed. The simulation results revealed a jet-like flow phenomenon when solitary waves passing over breakwaters due to the water level difference between the weather and lee sides of the …

New Tools For Viscoelastic Spectral Analysis, With Application To The Mechanics Of Cells And Collagen Across Hierarchies, Behzad Babaei

McKelvey School of Engineering Graduate Student Theses & Dissertations

Viscoelastic relaxation spectra are essential for predicting and interpreting the mechanical responses of materials and structures. For biological tissues, these spectra must usually be estimated from viscoelastic relaxation tests. Interpreting viscoelastic relaxation tests is challenging because the inverse problem is expensive computationally. We present here (1) an efficient algorithm and (2) a quasi-linear model that enable rapid identification of the viscoelastic relaxation spectra of both linear and nonlinear materials. We then apply these methods to develop fundamental insight into the mechanics of collagenous and fibrotic tissues.

The first algorithm, which we term the discrete spectral approach, is fast enough to …

Optimal Design Of Operation Parameters On Performance Of Pemfc, Ying-Pin Chang

Journal of Marine Science and Technology–Taiwan

This paper presents a method for combining sequential neural-network approximation and orthogonal arrays (SNAOA) in determining the operation parameters on the performance of the proton exchange membrane fuel cell (PEMFC). An orthogonal array was first conducted to obtain the initial solution set. The results obtained from the orthogonal array were then used as the experimental data for response surface methodology (RSM) that could predict the operation parameters at discrete levels. The set was then treated as the initial training sample. Next, a back-propagation sequential neural network was trained to simulate the feasible domain for seeking optimal operation parameters of PEMFC. …

Strategies To Improve The Direct Search Method For Non-Convex Wind-Thermal Coordination Dispatch Problem Considering Transmission Capacity, Chun-Lung Chen

Journal of Marine Science and Technology–Taiwan

This paper presents some strategies to improve the direct search method (DSM) for solving the multi-area wind-thermal coordination dispatch (MWCD) problem considering the nonlinear characteristics of a generator such as valve-point effects. Although the DSM approaches have several advantages suitable to tackle the difficult non-convex economic dispatch (NED) problems, they still have the drawbacks such as exploration problem, exploitation problem and constraint handling problem. The main problem of the conventional DSM is that it gets easily trapped in a local optimal solution due to premature convergence. This paper proposes a stochastic direct search method (SDSM) employing the parallel stochastic searching …

Application Of A Residual-Norm-Based Algorithm To Solve Elliptic Boundary Value Problems, Yung-Wei Chen, Chun-Ming Chang, Hui-Ming Fang, Pai-Chen Guan

Journal of Marine Science and Technology–Taiwan

In this study, we use a residual-norm-based algorithm (RNBA) to solve nonlinear elliptic boundary value problems (BVPs) on an arbitrary planar domain. For complex geometries, BVPs are very difficult and time-consuming to solve using conventional finite difference methods (FDMs). To overcome these problems, we apply a novel finite difference method (NFDM). By adding a fictitious rectangular domain and a bilinear function, we can easily treat geometrically complex boundary conditions. Then, through the use of the internal residual and the boundary residual, we can easily obtain the solution without the necessity of computing a matrix inverse. The RNBA avoids the oscillations …

Study On The New Variant Of Particle Swarm Method For Optimization Design, Jinn-Tong Chiu, Chih-Chung Fang

Journal of Marine Science and Technology–Taiwan

A new variant of Particle Swarm Optimization (PSO) is developed to improve the performance of PSO, which has been widely used in various fields for optimization. The proposed PSO incorporates a space partitioning technique in grid method with PSO. In the searching process of the new algorithm, three position vectors are introduced to enhance the exploration of the particles in the population of PSO and hence helpful for a global optimization problem of interest. First, the proposed variant of PSO is verified by applying it to the seven benchmark functions and thereafter proved from the results as a robust one. …

Intelligent Identification Of Fires In Ship Compartments Using A Bayesian Network, Tian-Hua Xie, Yan Lin, Wei Chi, Zu-Yao Yang

Journal of Marine Science and Technology–Taiwan

Fire is always a severe threat to ship safety and survival. To prevent the spread of a fire and eliminate serious accidental consequences, it is imperative for commanders to promptly identify the size and type of the fire so as to take rapid and effective firefighting action. In this study, the architectural design of an advanced ship fire identification system (SFIS) is presented that makes timely and critical decision support for selecting suitable suppression methods and firefighting tactics. Based on a Bayesian network (BN), a novel intelligent identification model that is capable of identifying small, medium or large fires and …

Novel Fault Diagnosis Method Based On Chaos Eyes And Extension Neural Network For Wind Power Systems, Meng-Hui Wang, Pi-Chu Wu

Journal of Marine Science and Technology–Taiwan

This paper proposes a novel approach based on the chaos eye method (CEM) and extension neural network (ENN) for fault diagnosis of wind power systems. First, we used sensors to capture the vibration signals of the wind power system to detect subtle changes. Subsequently, the chaotic synchronization detection method was used to form a chaos error distribution diagram. The distribution diagram centroid, called chaos eye in this paper, was used as the fault diagnosis feature to reduce the number of extracted features. This reduction in diagnostic features enables considerably reducing the computation time and cost of hardware implementation. The ENN-based …

Anchovy Distributional Properties By Time And Location: Using Acoustic Data From A Primary Trawl Survey In The South Sea Of South Korea, Yeongguel Park, Young Il Seo, Taeg Yun Oh, Kyounghoon Lee, Hui Zhang, Myounghee Kang

Journal of Marine Science and Technology–Taiwan

In South Korea, acoustic data from primary trawl surveys are not exploited. Thus, the objective of this study was to present the availability of acoustic data from a primary trawl survey by examining the distributional properties of anchovy schools by time (morning and afternoon) and location (inshore and offshore). Echosounder data were collected while conducting a trawl survey in the South Sea of South Korea on April 14-18, 2014. In six of eight trawl shots, the major species was anchovy Engraulis japonicus (> 95% of total catch weight). Consequently, the length, thickness, area, and volume backscattering strength (SV) of morning …

New Method For Inspecting The Status Of Submarine Pipeline Based On A Multi-Beam Bathymetric System, Chun-Bao Xiong, Zhi Li, Guo-Jun Zhai, Hua-Li Lu

Journal of Marine Science and Technology–Taiwan

Conventional methods for inspecting submarine pipelines under certain complex conditions are inadequate. A new method for inspecting the status of submarine pipeline based on a Multi-beam Bathymetric System (MBS) that can function under these conditions is proposed to resolve these shortfalls. Dual sonar sensors are employed in this method and the optimization of system parameters is undertaken to allow inspection of the submarine pipeline status in real-time at the Shengli Oil Field in Dongying, Shandong Province. The inspection results are presented in both two- and three-dimensions. Compared with the traditional MBS with a single sonar sensor, our tests indicate that …

Computational Fluid Dynamics Modeling And Simulations Of Fluidized Bed Reactors For Chemical Looping Combustion, Subhodeep Banerjee

McKelvey School of Engineering Graduate Student Theses & Dissertations

Chemical looping combustion (CLC) is a next generation combustion technology that shows great promise as a solution for the need of high-efficiency low-cost carbon capture from fossil fueled power plants. To realize this technology on an industrial scale, the development of high-fidelity simulations is a necessary step to develop a thorough understanding of the CLC process. Although there have been a number of experimental studies on CLC in recent years, CFD simulations have been limited in the literature.

In this dissertation, reacting flow simulations of a CLC reactor are developed using the Eulerian approach based on a laboratory-scale experiment of …