Engineering Commons^™

Assessing And Enhancing Nuclear Safety And Security Culture For Small Facilities That Handle Radioactive Material, Solymosi Máté

International Journal of Nuclear Security

The use of radioactive sources is expanding all over the world and abreast the necessity of the enhancement of its safe and secure application is increasing too. In the nuclear industry, the safety and security are top priorities since decades. They share the same goal, to protect humans from the negative affect of the ionizing radiation. The human component of them is a significant factor and technical solutions can protect us so far and thus the culture for safety and security become a major focus. On the other hand, there are still some contradiction between recommendations and international guidance of …

Strength Analysis For The Rudders Of Power-Free Underwater Vehicle In Kuroshio Subjected To Typhoon Waves, Chuan-Tsung Lee, Ray-Yeng Yang, Huang Hsing Pan, Li-An Kuo

Journal of Marine Science and Technology–Taiwan

In this study, a 1/25 hydraulic model of a power-free vehicle was developed. Typhoon waves and Kuroshio current flow in a wave-current flume (200 x 2 x 2 m3 ) were applied to the model for determining the net flow velocity and mooring forces. Through hydraulic experiments with a wave period of 16 s, wave height of 10 m, and ocean current speed of 1.0 m/s, a net flow velocity of up to 3.81 m/s was measured. The maximum lift and drag forces acting on each rudder were calculated through computational fluid dynamics as -245.6 and 151.6 kN, respectively, when …

Cascaded Uuv Trajectory Tracking Control Based On Model Predictive And Sliding Mode Control, Bing Sun, Wenyang Gan, Man Mei, Daqi Zhu, Simon X Yang

Journal of Marine Science and Technology–Taiwan

This paper describes a cascaded dynamic trajectory tracking control approach based on model predictive control (MPC) and sliding mode control for unmanned underwater vehicles (UUVs). The proposed method combines kinematic and dynamic controllers to achieve robust control. First, MPC is employed to realize tracking control kinematically. The MPC algorithm is proposed as a solution to the speed jump problem. Considering the computational burden for nonlinear UUV dynamic models, the MPC method is used in conjunction with sliding mode control to achieve dynamic tracking control, which solves problems of modeling uncertainty and external disturbances. Experimental results showed that the proposed method …

Investigation Of Effects Of Wave Directions On Hull Wave Loads By Hydroelastic Experimental Method, Zhanyang Chen, Jialong Jiao

Journal of Marine Science and Technology–Taiwan

This paper focuses on the hydroelastic responses of ultralarge vessels under different wave directions. Segmented ship model experiments provide an invaluable tool in naval applications. However, most model tests are performed on heading waves. Therefore, a segmented model with variable cross-section steel backbones was designed and the oblique wave tests were performed in a comprehensive test tank. The oblique wave test system was introduced in detail. Time histories of bending moments in oblique waves were given. In order to analyze the influence of structural elastic effect on hydroelastic responses, the number of segments of the model was changed, and the …

A Comparison Of The Aerodynamic Centers For Panel Code Compressible Corrections And Openfoam 5 For Mach 0.1 To 0.8, Dustin Weaver

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

It is known that the aerodynamic center changes from quarter chord to half chord from incompressible to compressible flows on airfoils. Compressible corrections are derived and implemented in a vortex panel code. These results will be used to find the aerodynamic centers for the specified Mach range of 0.1 to 0.8 in 0.1 increments within - 6 to 6 degrees angle of attack. OpenFOAM 5 cases will be created with specific meshes and settings. The results calculated from OpenFOAM 5 will be compared to the results obtained from the compressible corrections.

Determination Of Vertical Datum Level For Tidal Bench Mark Using Gnss Buoy Observations, Jae Young Roh, Kyung Wan Yoo, Yong Cheol Suh, Moon Seung Shin, Dong Ha Lee

Journal of Marine Science and Technology–Taiwan

Coastal areas are the most vulnerable areas to sea level fluctuations. Such areas comprise approximately 4% of South Korea's total land; therefore, monitoring these fluctuations is crucial. The present study determined the vertical datum level using a global navigation satellite system (GNSS). Unlike traditional sea level measurements, which are performed using fixed-type gauge observations, a GNSS has an accuracy of a few millimetres and no spatiotemporal constraints. For this purpose, a set of buoys containing GNSS devices was installed in coastal waters, and observations were performed for more than 8 h. The processed GNSS buoy data were compared with tidal …

Development Of Design Equations For Drilled Shafts In Granular Dense Soils Using Dem Simulations, Sadia Faiza

Civil Engineering ETDs

Drilled shafts have proven to be cost-effective, excellent performing, deep foundation systems where large loads and lateral resistance are major factors. The available design methods that are recommended by FHWA (2010) for drilled shafts are mostly empirical and are developed based on generalized data which sometimes can be conservative for a particular soil. The main objective of this study is to develop a design methodology for estimating the side resistance of an axially loaded drilled shaft based on the current and the unique properties of the soil. The objective was met through using the discrete element method (DEM) to investigate …

Characterization And Modeling Of Asphalt Concrete For Dynamic Properties And Performances, A S M A. Rahman

Civil Engineering ETDs

The recently developed mechanistic-empirical pavement design guide (MEPDG, also known as Pavement M-E design method) uses the nationally calibrated, binder viscosity-based dynamic modulus predictive model for the design and analysis of asphalt pavements. In this study, this model is assessed for its appropriateness for asphalt-aggregate mixtures typically used in New Mexico. In essence, this study investigates the predictability issue of complex modulus of New Mexico mixes. A total of 54 Superpave mixes with different aggregate gradations, air voids, and binder grades were collected from the mixing plants and from the pavement construction sites. The loose asphalt mixtures were then compacted, …

Next Generation Sequencing Technologies For Real-Time Genotyping And Targeted Sequencing For Precision Medicine, Priyanka Rawat

Biomedical Engineering ETDs

Astounding success of Human genome project and accelerating success of sequencing technologies have enabled $ 1000 genome goals possible. But, this is still far-fetched from the reach of many resource refrained populations with high genetic variations causing lethal genetic diseases. Based on present technology principles, I have developed prototypes for affordable, scalable and customizable point-of-care genotyping and targeted sequencing. Ion-sensitive field effect transistors with novel read-out and signal amplification techniques are used for laying foundation of possible ISFET based allele-arrays. Sequencing-by-synthesis based full-fledge sequencer is made with novel immobilization, flow-cell and data acquisition methods for massive sequenciing.

The Processing And Polarization Reversal Dynamics Of Thin Film Poly(Vinylidene) Fluoride, Noel Mayur Dawson

Nanoscience and Microsystems ETDs

Many ferroelectric devices benefit from the ability to deposit thin ferroelectric layers. Poly(vinylidene) fluoride (PVDF) is the prototypical ferroelectric polymer, but processing of thin film ferroelectric PVDF remains a challenge due to the formation of large voids in the film during traditional thin film processing. The research described in this dissertation starts by investigating the origin of these voids. The cause of these voids is found to be caused by vapor induced phase separation (VIPS). Guided by the thermodynamics of VIPS, a process is then designed to produce void-free ferroelectric PVDF thin films on polar and non-polar substrates. The films …

Co-Simulation Framework For Power Distribution System Analysis With Humans In The Loop, Victor H. Ayon

Mechanical Engineering ETDs

Recent developments in the area of power generation have led to an increased penetration of storage and distributed energy resources (DER) in power distribution systems. As a result, new and enhanced energy management systems will be necessary as the deployment of DERs, as well as the need to control loads, continues to increase in the coming years. Advanced management systems are especially important to achieve resilient power delivery during emergency situations. During a blackout for example, a section of a distribution feeder could island to operate as a microgrid to ensure critical services such as water, food, and medical care …

Characterization Of Structural Dynamics Of The Human Head Using Magnetic Resonance Elastography, Andrew Arun Badachhape

McKelvey School of Engineering Graduate Student Theses & Dissertations

In traumatic brain injury (TBI), the skull-brain interface, composed of three meningeal layers: the dura mater, arachnoid mater, and pia mater, along with cerebrospinal fluid (CSF) between the layers, plays a vital role in transmitting motion from the skull to brain tissue. Magnetic resonance elastography (MRE) is a noninvasive imaging modality capable of providing in vivo estimates of tissue motion and material properties. The objective of this work is to augment human and phantom MRE studies to better characterize the mechanical contributions of the skull-brain interface to improve the parameterization and validation of computational models of TBI. Three specific aims …

Abiotic- And Biotic-Formation Of Manganese Oxides And Their Fate In Environmental Systems, Haesung Jung

McKelvey School of Engineering Graduate Student Theses & Dissertations

Manganese (hydr)oxide (Mn (hydr)oxide) minerals are ubiquitous in aquatic and terrestrial environments. These minerals have high surface areas and are highly sorptive and redox active. From decades of accumulated knowledge about natural redox cycling, we have found that Mn (hydr)oxides play critical roles as electron donors and acceptors in elemental geochemical cycling and biological metabolisms in nature. Thus, Mn (hydr)oxides have garnered increasing interest to understand natural systems. Considering the variety of redox reactions with Mn (hydr)oxides in nature, it is also expected that there should be diverse pathways to form Mn (hydr)oxides through abiotic and biotic processes. Previous studies …

Two-Component Hydrogel As Biomimetic Vitreous Substitutes, Sruthi Santhanam

McKelvey School of Engineering Graduate Student Theses & Dissertations

The vitreous humor of the eye is a biological hydrogel principally composed of fibrillary collagen interspersed with semi-flexible polyelectrolyte, hyaluronic acid (HA). Certain pathological conditions necessitate its removal and replacement. Current vitreous substitutes, such as silicone oils and perfluorocarbons, are hydrophobic, do not resemble the properties of the vitreous, and have known complications. An ideal vitreous substitute should have properties of the natural vitreous, perform its functions, and be biocompatible in the eye. Inspired by the structure and composition of the natural vitreous, we used bio-mimicry to develop an injectable two-component hydrogel. The hydrogel is composed of a fibrillary gellan, …

Characterizing Anisotropy In Fibrous Soft Materials By Mr Elastography Of Slow And Fast Shear Waves, John Larson Schmidt

McKelvey School of Engineering Graduate Student Theses & Dissertations

The general objective of this work was to develop experimental methods based on magnetic resonance elastography (MRE) to characterize fibrous soft materials. Mathematical models of tissue biomechanics capable of predicting injury, such as traumatic brain injury (TBI), are of great interest and potential. However, the accuracy of predictions from such models depends on accuracy of the underlying material parameters. This dissertation describes work toward three aims. First, experimental methods were designed to characterize fibrous materials based on a transversely isotropic material model. Second, these methods are applied to characterize the anisotropic properties of white matter brain tissue ex vivo. Third, …

The Vibe, Sarah P. Douglass

Capstones

The Vibe is a long-form narrative about where tech is taking the female orgasm. The piece concludes that physiological research is a required next step when creating the climax of the future.

http://sarahpdouglass.com

Breadcrumbs: Privacy As A Privilege, Prachi Bhardwaj

Capstones

Breadcrumbs: Privacy as a Privilege Abstract

By: Prachi Bhardwaj

In 2017, the world saw more data breaches than in any year prior. The count was more than the all-time high record in 2016, which was 40 percent more than the year before that.

That’s because consumer data is incredibly valuable today. In the last three decades, data storage has gone from being stored physically to being stored almost entirely digitally, which means consumer data is more accessible and applicable to business strategies. As a result, companies are gathering data in ways previously unknown to the average consumer, and hackers are …

Modified Pid Controller Design For Active Transverse Anti-Rolling System For Ships With Low Roll Motion, Hsing-Cheng Yu, Jhih-Jyun You

Journal of Marine Science and Technology–Taiwan

Multi-domain physical modeling software with an intuitive simulation methodology using MapleSim was adopted in this study to create a rigid body structure model of an active transverse anti-rolling system (ATARS) of a container ship. At the same time, a ship stability analysis was also conducted to determine the force model, dynamic equilibrium, and motion behavior of the ATARS of the container ship. Once various external transverse force generated by waves impact varied roll angles of the ATARS on the vessel, a modified proportional-integral-derivative (PID) controller designed to improve the capability of the active stabilizer fins used in the ATARS is …

Experimental Assessment Of Suspended Sediment Concentration Changed By Solitary Wave, Jae-Nam Cho, Chang-Geun Song, Kyu-Nam Hwang, Seung-Oh Lee

Journal of Marine Science and Technology–Taiwan

A large scale solitary wave causes a lot of sediment transportation and coastal beach erosion, for example tsunami is the one type of solitary waves. During passing such solitary wave over coastal region, higher energy on sediment transportation near bottom would bring to massive geomorphological changes and even worse damages in life and economics. The major objective of this study is to analyze the incipient motion of sediment suspended from bottom by a solitary wave through hydraulic experiments and numerical simulations. First, to estimate the process of sediment transport the experimental study was carried out in the prismatic rectangular channel …

The Nonlinear Dynamics And Anti-Sway Tracking Control For Offshore Container Crane On A Mobile Harbor, You-Gang Sun, Hai-Yan Qiang, Junqi Xu, Da-Shan Dong

Journal of Marine Science and Technology–Taiwan

The offshore container crane (OCC), as a novel maritime container transfer system, can handle container from a large container-ship anchored in open sea to address the congestion and limited water-depth of port. However, for the wave- and wind-induced movements of the ship, the crane's control system should be redesigned to ensure the load transfer on the sea. In this paper, we derive the nonlinear dynamic equations of OCC system subjected to the ship motions based on dynamic analysis. Then a double-layer sliding manifold is constructed to realize the position tracking and sway control simultaneously, irrespective of ship motions and parameters …

Numerical Computation Of The Transient Salinity Distribution In A Macro-Tidal Estuary, Seung Oh Lee, Chang Geun Song

Journal of Marine Science and Technology–Taiwan

In this study, the flow reversal and salinity distribution associated with tidal effects were investigated at a macro-tidal estuary located in tidal range of the Yellow Sea in South Korea. A 2-D hydrodynamic model (RMA-2) and a 2D advectiondispersion model (RAM4) were employed to simulate flow behavior and salinity distribution, respectively. The results showed that reverse flow occurred five times over 3-day period and the maximum reverse flow extended over 32.9 km upstream. Salinity distribution was obtained by estimating the salinity input with analytical solution of advection-dispersion equation. The total length of the saline wedge calculated from numerical simulation was …

Simulation And Motion Analysis Of Deepwater Manifold Lifting, Zhiwei Chen, Tingdi Zhao, Jian Jiao, Dongfeng Mao

Journal of Marine Science and Technology–Taiwan

The development and utilization of oil and gas resources has expanded to deep water. The installation of a subsea manifold is crucial for developing offshore oil-gas fields. In this study, we used the lifting installation method (LIM) to install a subsea manifold. First, the appropriate environmental parameters were selected through the analysis of environmental loads at the Liwan 3-1 Gasfield in the South China Sea. The wind and wave spectra were selected using noise power density and Joint North Sea Wave Project spectra, respectively. The entire lifting and installation system that responds to environmental loads comprised a vessel, cable, and …

Energy Efficient Trajectory Design For The Underwater Vehicle With Bounded Inputs Using The Global Optimal Sliding-Mode Control, Mai The Vu, Hyeung-Sik Choi, Jin-Il Kang, Dae-Hyung Ji, Hyun Joong

Journal of Marine Science and Technology–Taiwan

In this paper, we propose a novel global sliding mode controller (SMC) for an uncertain linear time-varying second order system. The proposed controller was implemented on the underwater vehicle (UV) with uncertainty of bounded parameters and disturbances within limited control input. By applying the proposed controller to the second-order UV system, the arrival time at the reference position and the maximum allowable acceleration are expressed in a closed-form equation if ranges of parametric uncertainties and reference inputs are specified. The closed-form equation can be utilized in designing the capacity of vehicle systems with the condition of the minimum arrival time …

Real-Time Method For Calculating Retardation Functions, Li-Hao Yuan, Yue-Sheng Ma, Ying-Fei Zan, Zhao-Hui Wu

Journal of Marine Science and Technology–Taiwan

To meet the demand for real-time calculation of time-domain motion equations, a state-space model was established to replace the convolution integral method to improve computational efficiency. On the basis of the HYSY201 vessel, the impulse response curve fitting method and the realization theory method based on the time-domain identification theory were compared to establish the state-space model. The results of roll decay simulation conducted using the state-space model and the convolution integral method were verified against decay test results. The simulation results for retardation function, radiation forces, and motion time histories calculated using the state-space model and the convolution integral …

Survey Of Trajectory Tracking Control Of Autonomous Underwater Vehicles, Wen-Yang Gan, Da-Qi Zhu, Wei-Li Xu, Bing Sun

Journal of Marine Science and Technology–Taiwan

Autonomous underwater vehicles (AUVs) are powerful instruments that enable the exploration of the ocean. In recent years, AUVs have been developed considerably. Trajectory tracking control, which has been a major research focus for many decades due to its variety of applications, is one of the key advancements in the AUV technology. This paper presents six trajectory tracking control methods: PID (proportion integration differentiation) control, fuzzy control, adaptive control, sliding mode control, backstepping control, and neural network control. A few novel methods for trajectory tracking control are also introduced. First, the concept of trajectory tracking control for an AUV and the …

Modeling Of Dynamic Behavior For Port Structures Using The Performance-Based Seismic Design, Cheng-Yu Ku, Jing-Jong Jang, Jui-Ying Lai, Ming-Jr Hsieh

Journal of Marine Science and Technology–Taiwan

The paper presents a pioneer study on numerical modeling of dynamic behavior for port structures using the performancebased seismic design in Taiwan. Since Taiwan is located in earthquake prone area, there is significant interest in improving prediction of the behavior of port structures subjected to seismic loading. The investigation of port structures using three different analysis methods including the simplified analysis, the simplified dynamic analysis, and the dynamic analysis were adopted for evaluating the performance of the cellular quay wall and sheet pile quay wall. In addition, the effective stress analysis with the consideration of the pore pressure generation and …

Cost Of Salvage?€“ A Comparative Form Approach, Chung-Sheng Chiu, Chung-Ping Liu, Ki-Yin Chang, Wen-Jui Tseng, Yung-Wei Chen

Journal of Marine Science and Technology–Taiwan

The most important principle of salvage is the "No Cure-No Pay" basis, if there is no recovery, there is no payment, whatever the expense of the operation. However, this principle has changed in recent years to reflect the public interest in prevention of damage to the environment (Mudric, 2010). The salvor can now contract in such a way that he is shielded from loss when responding to high risk or low value casualties (so called as "No Cure-Some pay"). Salvage is a high-profit business and high-risk as well in the world. The case of the Costa Concordia - by no …

A Numerical Model For Pipeline Abandonment In Deep Water, Duanfeng Han, Kuo Huang, Yingfei Zan, Zhaohui Wu

Journal of Marine Science and Technology–Taiwan

In offshore oil and gas engineering, pipeline abandonment is unavoidable and its mechanical analysis is necessary and important. For this problem, a numerical model is developed in this study to evaluate pipeline abandonment for the J-laying method. The whole system considered in this model is divided into two parts: the A&R cable and the pipeline in the water. A catenary model was proposed for the former, and the latter is solved by a numerical iterative method. In addition to the boundary conditions at the two end points, a special set of boundary conditions is required at the junction that connects …

Experimental Study Of Dynamic Stability Of Underwater Vehicle-Manipulator System Using Zero Moment Point, Jin-Il Kang, Hyeung-Sik Choi, Mai The Vu, Nguyen Ngoc Duc, Dae-Hyeong Ji, Joon-Young Kim

Journal of Marine Science and Technology–Taiwan

For manipulative underwater operations, an underwater vehiclemanipulator system (UVMS) has more degrees of freedom than those required to conduct a given mission. To follow the desired end-effector position and velocity accurately, UVMS should be able to generate trajectories of manipulators and the underwater vehicle can maintain dynamic stability of the entire system. In this paper, redundancy resolution is performed to find a solution satisfying the given task among many joint-space solutions. Also, to improve the dynamic stability of the UVMS, zero moment point (ZMP) is adopted such that it requires some constraints. For application of UVMS, a joint limitation is …

A Time-Domain Numerical Tool For A Wave Energy Attenuator With The Sph Method, Da-Wei Chen, Shuichi Nagata, Shiaw-Yih Tzang, Yasutaka Imai, Chih-Min Hsieh, Jiahn-Horng Chen

Journal of Marine Science and Technology–Taiwan

The wave energy attenuator is a floating device which operates perpendicular to the wave fronts and captures wave energy from the relative motions of two hinged floaters as waves passing by them. For establishing the time-domain numerical tools to evaluate the performance of a wave energy attenuator, a Smoothed Particle Hydrodynamic (SPH) model with mesh-free method was adopted to simulate the hydrodynamic behaviors of each floating object. Three different wave heights of 6 cm, 7 cm, and 10.4 cm of the same period of 1.22 s were commonly derived from typical potential oceanic zones offshore Taiwan and Japan. Comparisons of …