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Articles 3661 - 3690 of 11196

Full-Text Articles in Aerospace Engineering

Multiple-Site Fatigue Cracking Methodology To Assess Structural Integrity Of Aircraft Riveted Panels, Haroldo Chacon Jan 2021

Multiple-Site Fatigue Cracking Methodology To Assess Structural Integrity Of Aircraft Riveted Panels, Haroldo Chacon

Masters Theses

“Multiple Site Damage (MSD) is the most common source of Widespread Fatigue Damage (WFD) affecting structural integrity of aging aircraft fleets. Therefore, an understanding of its progression, the development of methods to prevent the onset, and the maintenance procedures precluding WFD are important to improve aircraft fleet longevity. A reliable and efficient numerical methodology to perform detailed Multiple Site Damage assessment in riveted structural joints was developed. A probabilistic methodology was employed in conjunction with Monte Carlo simulation technique; the fatigue initiation life at every potential crack initiation site was determined and initial damage scenarios were generated. Probabilistic crack growth …

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Fluid-Wall Interactions In Pseudopotential Lattice Boltzmann Models, Cheng Peng, Luis F. Ayala, Orlando M. Ayala Jan 2021

Fluid-Wall Interactions In Pseudopotential Lattice Boltzmann Models, Cheng Peng, Luis F. Ayala, Orlando M. Ayala

Engineering Technology Faculty Publications

Designing proper fluid-wall interaction forces to achieve proper wetting conditions is an important area of interest in pseudopotential lattice Boltzmann models. In this paper, we propose a modified fluid-wall interaction force that applies for pseudopotential models of both single-component fluids and partially miscible multicomponent fluids, such as hydrocarbon mixtures. A reliable correlation that predicts the resulting liquid contact angle on a flat solid surface is also proposed. This correlation works well over a wide variety of pseudopotential lattice Boltzmann models and thermodynamic conditions.

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The Need For Aerospace Structural Health Monitoring: A Review Of Aircraft Fatigue Accidents, Luke Pollock, Ayah Khalid Abdelwahab, John Murray, Graham Wild Jan 2021

The Need For Aerospace Structural Health Monitoring: A Review Of Aircraft Fatigue Accidents, Luke Pollock, Ayah Khalid Abdelwahab, John Murray, Graham Wild

Research outputs 2014 to 2021

Aircraft accidents involving catastrophic fatigue failure have the potential for significant loss of life. The aim of this research was to investigate trends in aircraft fatigue failure accidents to inform aerospace Structural Health Monitoring (SHM) system Research and Development (R&D). The research involved collecting 139 aircraft fatigue failure accident reports from the Aviation Safety Network database, which were coded using a directed content analysis. The trends and features of the categorical data were then explored using an ex-post facto study. The results showed that fatigue failure accidents have increased at a rate of (3.4 ± 0.6)×10-2 per year since the …

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Design, Fabrication And Analysis Of Novel Dragonfly-Bioinspired, Flapping Wing System For A Micro Air Vehicle, Erfan Salami Jan 2021

Design, Fabrication And Analysis Of Novel Dragonfly-Bioinspired, Flapping Wing System For A Micro Air Vehicle, Erfan Salami

Student Works (2020-2029)

In the recent decades, the design and development of biomimetic micro air vehicles (BMAV) have gained increased interest from the global scientific and engineering communities. This has given greater motivation to study and understand the aerodynamics involved with winged insects. Dragonflies demonstrate unique and superior flight performance than most of the other insect species and birds. They are capable of sustained gliding flight as well as hovering and are able to change direction very rapidly. Pairs of independently controlled forewings and hindwings give them an agile flying ability. There are still many technological challenges involved with designing the BMAV. One …

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Understanding Flow Characteristics In Metal Additive Manufacturing, Carl R. Hartsfield, Travis E. Shelton, Gregory R. Cobb, Ryan A. Kemnitz, Joseph Weber Jan 2021

Understanding Flow Characteristics In Metal Additive Manufacturing, Carl R. Hartsfield, Travis E. Shelton, Gregory R. Cobb, Ryan A. Kemnitz, Joseph Weber

Faculty Publications

In fluid flow, the frictional effects from interior surfaces of flow components create pressure loss across the surface. Understanding this inherent pressure loss due to friction and other phenomena is important when designing a flow system. For conventional manufacturing, friction loss has been empirically studied and is well known in the engineering community. However, newer manufacturing techniques, such as laser powder bed fusion (LPBF), an additive manufacturing technique, need to be understood. The inherent flow conditions resulting from the additive processes were studied. Test samples were printed with the flow path oriented in the vertical direction with different channel diameters …

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Modeling And Simulation Of Electromagnetic Fields To Maintain Bone Density During Prolonged Low Gravity Exposure, Austin Tapp, Michael Francis, Michel A. Audette Jan 2021

Modeling And Simulation Of Electromagnetic Fields To Maintain Bone Density During Prolonged Low Gravity Exposure, Austin Tapp, Michael Francis, Michel A. Audette

Electrical & Computer Engineering Faculty Publications

Astronauts in a long term, low-gravity environments experience bone density loss at 10 times the rate of those diagnosed with osteoporosis. One treatment effective at maintaining bone density in osteoporotic individuals is electromagnetic field (EMF) therapy. Tools that induce EMFs are becoming increasingly prevalent, but to amplify osteogenesis and encourage superior bone density retention for astronauts, ideal EMF therapy parameters must be determined on patient-specific bases. Therefore, this study explores simulation environments that elucidate highly favorable EMF factors. Pulsed electromagnetic field and combined magnetic field generating devices are variably introduced near partient-specific, finite element (FE) models of the femur, spine, …

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Resilience For Multi-Filter All-Source Navigation Framework With Integrity, Jonathon S. Gipson, Robert C. Leishman Jan 2021

Resilience For Multi-Filter All-Source Navigation Framework With Integrity, Jonathon S. Gipson, Robert C. Leishman

Faculty Publications

The Autonomous and Resilient Management of All-source Sensors (ARMAS) framework monitors residual-space test statistics across unique sensor-exclusion banks of filters, (known as subfilters) to provide a resilient, fault-resistant all-source navigation architecture with assurance. A critical assumption of this architecture, demonstrated in this paper, is fully overlapping state observability across all subfilters. All-source sensors, particularly those that only provide partial state information (altimeters, TDoA, AOB, etc.) do not intrinsically meet this requirement.
This paper presents a novel method to monitor real-time overlapping position state observability and introduces an "observability bank" within the ARMAS framework, known as Stable Observability Monitoring (SOM). SOM …

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Dances And Escape Of The Vortex Quartet, Brandon Behring Dec 2020

Dances And Escape Of The Vortex Quartet, Brandon Behring

Dissertations

This dissertation considers the linear stability of a one-parameter family of periodic solutions of the four-vortex problem known as 'leapfrogging' orbits. These solutions, which consist of two pairs of identical yet oppositely-signed vortices, were known to W. Gröbli (1877) and A. E. H. Love (1883) and can be parameterized by a dimensionless parameter related to the geometry of the initial configuration. Simulations by Acheson and numerical Floquet analysis by Tophøj and Aref both indicate, to many digits, that the bifurcation occurs at a value related to the inverse square of the golen ratio. Acheson observed that, after an initial period …

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Research On Structural Design And Vision System Of Narrow Shallow Water Multipurpose Underwater Robot, Nan Pan, Xiao-Jue Guo, Jun-Bing Qian, Yong-You Luo, Yi Liu Dec 2020

Research On Structural Design And Vision System Of Narrow Shallow Water Multipurpose Underwater Robot, Nan Pan, Xiao-Jue Guo, Jun-Bing Qian, Yong-You Luo, Yi Liu

Journal of Marine Science and Technology–Taiwan

In the narrow shallow water area, the underwater environment is complex and changeable, and the water area is narrow. Because of water body flow, various risks and unpredictable conditions, such as turbulence, vortex, disturbance, and so on exist which could seriously interfere with the motion and control of the underwater vehicle. In this way, the automatic stability and flexibility of multi-dimensional motion under external disturbance becomes the basis and requirement of underwater control and operation. In this paper, the structure design of the main body and power system of the narrow shallow water multi-purpose underwater vehicle was proposed to realize …

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Study On Multi-Dof Search And Salvage Robot In Shallow Water, Jun-Bing Qian, Nan Pan, Xiao-Jue Guo, Yi Liu Dec 2020

Study On Multi-Dof Search And Salvage Robot In Shallow Water, Jun-Bing Qian, Nan Pan, Xiao-Jue Guo, Yi Liu

Journal of Marine Science and Technology–Taiwan

For underwater robots working in a variety of risky, unpredictable, and complex underwater environments – with factors such as turbulence, vortex, wind, wave, and deep-water pressure – it is necessary to ensure good structural design and handling performance in the process of robot design. Based on the requirements of achieving the stability design, control system, and underwater vision system of the robot, this paper proposes the structural design of a police multipurpose underwater robot power system that realizes both stable and flexible movement. A 6-DOF driving method was designed and its motion analysis was performed. In the vision system, an …

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A Study On An Accurate Underwater Location Of Hybrid Underwater Gliders Using Machine Learning, Sang-Ki Jeong, Hyeung-Sik Choi, Dea-Hyung Ji, Mai The Vu, Joon-Young Kim, Sung Min Hong, Hyun Joon Cho Dec 2020

A Study On An Accurate Underwater Location Of Hybrid Underwater Gliders Using Machine Learning, Sang-Ki Jeong, Hyeung-Sik Choi, Dea-Hyung Ji, Mai The Vu, Joon-Young Kim, Sung Min Hong, Hyun Joon Cho

Journal of Marine Science and Technology–Taiwan

A hybrid underwater glider (HUG) is marine observation equipment that consumes a small amount of energy and offers greater range and navigation times. To achieve reduced energy consumption, however, the HUG uses imprecise navigation sensors, such as mems-type GPS and AHRS, resulting in inaccurate coordination. This study makes a new attempt on the application of machine learning algorithms in a way that complements sensor data errors to improve navigation performance. The proposed algorithm was used to a simulation of the HUG’s navigation and control system, after which the updated heading angle was decided by using the previous position data and …

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A New Complex Marine Unmanned Platform And Field Test, Jihyeong Lee, Han-Sol Jin, Hyunjoon Cho, Jiafeng Huang, Sang-Ki Jeong, Dae-Hyeong Ji, Hyeung-Sik Choi Dec 2020

A New Complex Marine Unmanned Platform And Field Test, Jihyeong Lee, Han-Sol Jin, Hyunjoon Cho, Jiafeng Huang, Sang-Ki Jeong, Dae-Hyeong Ji, Hyeung-Sik Choi

Journal of Marine Science and Technology–Taiwan

This paper presents the development of a new complex marine unmanned platform composed of an unmanned surface vehicle (USV) and a remotely operated vehicle (ROV), and the results of a sea test. The platform structure, control system, sensor system, and control algorithm were developed and are introduced. The complex platform collects information of the underwater structures, such as the wall, floor, and piers and harbors. Using a tether cable, the ROV is connected to the USV for power supply and to receive a large amount of underwater data obtained using a sonar scanner or a camera in real time. The …

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A Study On Hydrodynamic Forces Induced By Liquid Tank Of Lng Carrier In Waves Based On Experiment And Recurrent Neural Network, Van Minh Nguyen, Thi Thanh Diep Nguyen, Hyeon Kyu Yoon Dec 2020

A Study On Hydrodynamic Forces Induced By Liquid Tank Of Lng Carrier In Waves Based On Experiment And Recurrent Neural Network, Van Minh Nguyen, Thi Thanh Diep Nguyen, Hyeon Kyu Yoon

Journal of Marine Science and Technology–Taiwan

The sloshing of liquid in a partially filled tank is of great concern to aerospace vehicles, road vehicles and ships due to complex nonlinear motion involving the free surface of the liquid. Sloshing is a type of violent liquid motion that is created by forces such as an impact and breaking waves. Oscillation of the liquid in the vessel may threaten navigation safety. This paper attempts to predict the hydrodynamic forces induced by the motion of liquid inside a tank based on experiment and Recurrent Neural Network (RNN). The experiment of sloshing test is carried out using the Stewart platform …

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Collision Warning System For Small Maritime Autonomous Surface Ships, Won-Sik Kang, Young-Soo Park, Jeong-Bin Yim Dec 2020

Collision Warning System For Small Maritime Autonomous Surface Ships, Won-Sik Kang, Young-Soo Park, Jeong-Bin Yim

Journal of Marine Science and Technology–Taiwan

In this study, wireless communication technologies used in road and marine traffic are compared and analyzed to develop a collision warning system for small maritime autonomous surface ships based on sufficient testing and technologically advanced wireless access in vehicular environment (WAVE) communication technology. Outstanding communication technologies, such as WAVE, have been used as the core technology for the infrastructural development of an intelligent transport system (ITS) as well as autonomous vehicles in many countries and industries. In WAVE communication, information is transmitted in 100-ms intervals. Therefore, it is feasible to maintain control of ships by fully supplementing the update interval …

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Modeling Navigator Errors In Collisions Using Hidden Markov Models, Deuk-Jin Park, Jeong-Bin Yim, Chun-Ki Lee Dec 2020

Modeling Navigator Errors In Collisions Using Hidden Markov Models, Deuk-Jin Park, Jeong-Bin Yim, Chun-Ki Lee

Journal of Marine Science and Technology–Taiwan

Understanding navigator errors can be used as a basis for preventing collisions. Here, Hidden Markov Models (HMMs) are applied to navigator errors of fishing and merchant ships in collisions. Information on navigator errors providedin accident investigation reports issued by the Korean Maritime Safety Tribunal is surveyed. The surveyed information is converted into data using the framework of slips, lapses, and mistakes proposed in this study. The results of framework data states are inferred using the unsupervised learning of HMMs, with sequences of navigator errors contained in the error data. The expected errors learned using the navigator error models for fishing …

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Remote Sensing Analysis Of Cold Water Temporal And Spatial Variability In The East Sea, Suk Yoon, Hyun Yang Dec 2020

Remote Sensing Analysis Of Cold Water Temporal And Spatial Variability In The East Sea, Suk Yoon, Hyun Yang

Journal of Marine Science and Technology–Taiwan

In this study, we monitored temporal and spatial variability in summer cold water events in the East Sea of Korea. We defined cold water as seawater that is ≥ 5°C colder than the surrounding area. When cold water expands or changes in propagation direction, the National Institute of Fisheries Science (NIFS) of Korea issues a cold water upwelling warning to prevent aquafarm damage. To understand cold water effects, we analyzed the causes of continuous and strong cold water events, and propagation thereof, using satellite and in situ data for summer to autumn in the period 2011–2019. To investigate the cold …

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Short-Term Fatigue Damage Of Tethers Of Long-Span Floating Cable Supported Bridges Under Harsh Waves, Deokhee Won, Keesei Lee, Young-Jong Kang, Seungjun Kim Dec 2020

Short-Term Fatigue Damage Of Tethers Of Long-Span Floating Cable Supported Bridges Under Harsh Waves, Deokhee Won, Keesei Lee, Young-Jong Kang, Seungjun Kim

Journal of Marine Science and Technology–Taiwan

A floating bridge can be effectively used for sea-crossing in deep water. Because the superstructure of the bridge is supported by floating substructures with pontoons, the conventional fixed piers, towers, foundations, and piles are not required. Instead, a rational mooring system can be used to strictly maintain the target position of the floating substructures against environmental loads, including winds, waves, and currents. Recently, long-span cable-supported bridges with floating towers were investigated and found to overcome the limitations of conventional cable-supported bridges, when used as sea-crossing infrastructure. To design the moorings for very large floating structures, the structural safety should be …

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Dynamic Modelling And Experimental Results Of A Ray-Type Hybrid Underwater Glider With A Dualbuoyancy Engine, Ngoc-Duc Nguyen, Hyeung-Sik Choi, Sung-Wook Lee, Wen-Hsiang Hsieh, Sang-Ki Jeong, Dae-Hyeong Ji Dec 2020

Dynamic Modelling And Experimental Results Of A Ray-Type Hybrid Underwater Glider With A Dualbuoyancy Engine, Ngoc-Duc Nguyen, Hyeung-Sik Choi, Sung-Wook Lee, Wen-Hsiang Hsieh, Sang-Ki Jeong, Dae-Hyeong Ji

Journal of Marine Science and Technology–Taiwan

For ocean observation and exploration, underwater gliders (UG) have shown their efficient long-range operation with buoyancy propulsion. The current Torpedo-shape UGs have small buoyancy capacity and insufficient space for batteries and sensors. In this paper, a Ray-type hybrid underwater glider (RHUG) is developed with new hull design, dual-buoyancy engine, and thrusters. The control system of the RHUG is constructed for gliding motion. To understand the characteristic of the RHUG, dynamic modelling of the dual-buoyancy engine was established. To verify the proposed dynamics model, a navigation experiment using the developed RHUG platform was carried out. Through comparison between experiment and simulation …

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Development Of Collision Avoidance Algorithm Based On Consciousness Of Ship Operator, Eunkyu Lee, Young-Soo Park, Minjeong Park, Myoung-Ki Lee, Eunbi Park, In-Young Gong Dec 2020

Development Of Collision Avoidance Algorithm Based On Consciousness Of Ship Operator, Eunkyu Lee, Young-Soo Park, Minjeong Park, Myoung-Ki Lee, Eunbi Park, In-Young Gong

Journal of Marine Science and Technology–Taiwan

Several collision avoidance algorithms employing various methods have been developed to date. In this paper, a collision avoidance algorithm is proposed based on the potential assessment of risk (PARK) model, which is a maritime traffic risk assessment model based on the characteristics of the Korean coastal regions and the consciousness of a ship’s operator. The proposed collision avoidance algorithm is intended to be used in the transition period during which autonomous and human-operated ships sail simultaneously. The algorithm avoids collisions using the PARK model that reflects the International Regulations for Preventing Collisions at Sea. Situations such as head-on, crossing, overtaking, …

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Identifying High-Collision Potential Vessel-Bridge Pairs In Vessel Traffic Service, Jeong-Bin Yim, Chun-Ki Lee Dec 2020

Identifying High-Collision Potential Vessel-Bridge Pairs In Vessel Traffic Service, Jeong-Bin Yim, Chun-Ki Lee

Journal of Marine Science and Technology–Taiwan

Collision risk assessment for maritime traffic monitoring in vessel traffic service (VTS) is a key technology for ensuring the safety of both vessels and bridges. This study proposes a risk assessment methodology using a single measure of collision risk ratio that could assist in reducing the cognitive load of VTS operators. To explain the proposed method, we first define the semantic and mathematical relationship of vessel– bridge pier collisions; then, we establish the risk assessment framework using the collision risk ratio by combining deviation angle and stopping distance probabilities. To validate the proposed method, we conducted an experiment in the …

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Experimental And Numerical Investigations On The Hydrodynamic Characteristics Of The Planar Motion Of An Open-Frame Remotely Operated Vehicle, Ying-Fei Zan, Rui-Nan Guo, Li-Hao Yuan, Shi-Peng Wang, Da-Zhong Zhang, Shi-Jing Xu, Zhao-Hui Wu Dec 2020

Experimental And Numerical Investigations On The Hydrodynamic Characteristics Of The Planar Motion Of An Open-Frame Remotely Operated Vehicle, Ying-Fei Zan, Rui-Nan Guo, Li-Hao Yuan, Shi-Peng Wang, Da-Zhong Zhang, Shi-Jing Xu, Zhao-Hui Wu

Journal of Marine Science and Technology–Taiwan

In this study, the longitudinal, sideways, vertical, and sideslip motions of an open-frame remotely operated vehicle (ROV) were experimentally and numerically investigated. The open-frame ROV was designed to be asymmetric in both the longitudinal and vertical directions to achieve special functionalities. A physical ROV model was tested in a towing tank with different velocities and sideslip angles in the horizontal and vertical planes. A numerical simulation was conducted with the same working conditions used in the scaled model tests by using a segregated flow solver based on Reynolds-averaged Navier–Stokes equations. This study investigated the effect of the hydrodynamic forces (moments) …

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An Enhanced Sliding Mode Control Method For Wave Compensation System Of Ship-Mounted Cranes With Roll Motions And Parametric Uncertainties, Hai-Yan Qiang, Si Xie, Zhi-Qiang Xu, You-Gang Sun Dec 2020

An Enhanced Sliding Mode Control Method For Wave Compensation System Of Ship-Mounted Cranes With Roll Motions And Parametric Uncertainties, Hai-Yan Qiang, Si Xie, Zhi-Qiang Xu, You-Gang Sun

Journal of Marine Science and Technology–Taiwan

Ship-mounted cranes are widely used in offshore constructions, resource exploitation and marine salvages, to transfer payloads. Due to serious sea conditions, unexpected motions of the ships caused by the wave will probably pose serious efficiency and security issues. Thus, the wave compensation system has become necessary equipment for the shipmounted crane. But wave-induced motions of the ship, parametric uncertainties and nonlinearities remain challenges for control of wave compensation systems, which needs to be solved urgently. In this paper, the mathematical model of the wave compensation system is established firstly. Then, a sliding mode controller is presented and the stability is …

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Study On Underwater Navigation For Underwater Track Vehicle, Dae-Hyeong Ji, Hyeung-Sik Choi, Sang-Ki Jeong, Hyun-Joon Cho, Ji-Hyeong Lee, Wen-Hsiang Hsieh Dec 2020

Study On Underwater Navigation For Underwater Track Vehicle, Dae-Hyeong Ji, Hyeung-Sik Choi, Sang-Ki Jeong, Hyun-Joon Cho, Ji-Hyeong Lee, Wen-Hsiang Hsieh

Journal of Marine Science and Technology–Taiwan

In this study, an underwater navigation algorithm was developed to apply a navigation system to an underwater track vehicle (UTV). Generally, a Doppler velocity log (DVL) is used to obtain the velocity information of underwater vehicles. However, a DVL cannot be used in a UTV owing to vehicle vibration and limited sensing distance. Hence, dead reckoning navigation is typically used, which results in severe errors in altitude and position values over long periods of operation. To address these problems, in this study, we developed a new underwater navigation system for a UTV using navigation sensors comprising an inertial navigation system, …

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A Study On The Analysis Of Minimum Speed Control Effect Using Queue Model Focused On Busan Port, Sangwon Park, Won-Sik Kang, Young-Soo Park Dec 2020

A Study On The Analysis Of Minimum Speed Control Effect Using Queue Model Focused On Busan Port, Sangwon Park, Won-Sik Kang, Young-Soo Park

Journal of Marine Science and Technology–Taiwan

VTS aims to increase the efficiency of maritime traffic in two ways. The first is a decrease in marine accidents, and the second is an increase in the utilization rate of infrastructure such as waterways and port facilities. This means that, if safety is guaranteed, efficiency must also be considered in the VTS. The purpose of this study is to quantitatively analyze the effects of speed regulation under safe conditions for an efficient use of waterways. A model was developed using a queue approach, and the effect of the waiting time according to the minimum speed proposal was analyzed through …

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Vision Based Target Recognition For Cage Aquaculture Detection, Chao-Xun Chen, Jih-Gau Juang Dec 2020

Vision Based Target Recognition For Cage Aquaculture Detection, Chao-Xun Chen, Jih-Gau Juang

Journal of Marine Science and Technology–Taiwan

This study applies Unmanned Aerial Vehicle (UAV) to netcage fish-farming. The UAV can fly thru cages along a predefined route. At each cage, the UAV can automatically drop sensors to collect the environment data around the cage. However, low cost commercial or assembled drone might not have precise Global Navigation Satellite System (GNSS). Also, there are many uncertain factors cause Global Positional System (GPS) instability, like weather, location…etc. The main idea of this study is using GPS to guide the drone to approximated location of each cage. Then, apply image recognition to obtain the net-cage and UAV relative position. After …

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Dynamic Behavior Of A Long-Span Cable-Stayed Bridge With Floating Towers After The Sudden Failure Of Tethers And Cables Under Irregular Waves, Minseo Jang, Yunwoo Lee, Seungjun Kim, Young-Jong Kang Dec 2020

Dynamic Behavior Of A Long-Span Cable-Stayed Bridge With Floating Towers After The Sudden Failure Of Tethers And Cables Under Irregular Waves, Minseo Jang, Yunwoo Lee, Seungjun Kim, Young-Jong Kang

Journal of Marine Science and Technology–Taiwan

Cable-supported bridges with floating towers do not require fixed piers at the seabed. Therefore, innovative conceptual models have been continuously developed to overcome the limitations of conventional bridges in deep waters. The main floating tower that supports superstructures using stay cables is balanced by the buoyancy of floaters moored by tethers. The applicability of floating bridges should be verified by evaluating the overall stability considering the tether design. Here, various cases of the sudden failure of tethers and stay cables under the environmental conditions of a 100-year return period are simulated in a time-domain. The floating cable-stayed bridges are subjected …

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Internal Force Evaluation Of A Submerged Floating Pipeline Under Irregular Waves, Deokhee Won, Jihye Seo, Jong Sup Park, Seungjun Kim Dec 2020

Internal Force Evaluation Of A Submerged Floating Pipeline Under Irregular Waves, Deokhee Won, Jihye Seo, Jong Sup Park, Seungjun Kim

Journal of Marine Science and Technology–Taiwan

Generally, submarine pipelines are laid on the seabed to transport water, oil, natural gas, and electricity to the land using submarine cables. However, they are not suitable for all seafloor conditions. There are environmental concerns such as deep seas, irregular seabed features, soft soils, transported materials and so on. To overcome these challenges, a submerged floating pipeline (SFP) concept was proposed. To stay in the middle of the water, the SFP has buoyant modules as floating devices. It is unrestricted under environments such as uneven seabeds, and deep waters, and is suspended to avoid interrupting passing vessels. This SFP model …

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Design And Control Techniques Of The Open-Circuit Subsonic Wind Tunnel With Closed Testing Section, Jamshid Yakhshilikov, Jamshid Inoyatkhodjaev Dec 2020

Design And Control Techniques Of The Open-Circuit Subsonic Wind Tunnel With Closed Testing Section, Jamshid Yakhshilikov, Jamshid Inoyatkhodjaev

Acta of Turin Polytechnic University in Tashkent

This paper will describe the design and control techniques of the open-circuit subsonic wind tunnel with closed testing section (WT) for study purpose. The goal is to design a WT that can be tested at a wind speed of 30 m/s, where the desired cross-sectional area of the test chamber is 0.5x0.5 m. The pressure drop inside the WT has been calculated in order to select one of the available axial fans from the manufacturer’s catalog, and computational fluid dynamics (CFD) was performed to check the result. In order to obtain a smooth airflow in the test section, a proportional …

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The Earliest Drawings Of Dogs, Myles Bradley Dec 2020

The Earliest Drawings Of Dogs, Myles Bradley

Fall Student Research Symposium 2020

The oldest depictions of dogs ever found are over 8,000 years old, found carved into a cliff in the desert of Saudi Arabia. Studies show, however, that dogs are found coexisting with humans as far back as 30,000 years ago. If this is the case, "Why does it take so long for dogs to appear in human artwork?" Dogs have certainly been an integral part of human society for almost as long as they've been around, so what do these early images reveal about the ancient relationship between dogs and man? This paper explores possible answers to both of these …

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Static Heat Exchanger For The Wireless Charging Of Electric Vehicles, James Mullen Dec 2020

Static Heat Exchanger For The Wireless Charging Of Electric Vehicles, James Mullen

Fall Student Research Symposium 2020

The USU College of Engineering partnered with the Aspire NSF Engineering Research Center to develop wireless charging pads for electric vehicles. These concrete pads, when placed in roadways, charge the batteries of electric vehicles that pass over them. As the pads charge vehicles, they produce excessive thermal energy (heat), which dissipates slowly through the surrounding concrete. This excess heat reduces the efficiency of the charging apparatus and can damage the imbedded electrical components. To manage the pad temperatures, the USU Nanoscale Thermal Energy Lab proposed to submerge the heat-generating elements in a Phase Change Material (PCM). As a solid, a …

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