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An Exploration Of The Application Of Desalination In Disaster Relief, Emma Sager 2023 Liberty University

An Exploration Of The Application Of Desalination In Disaster Relief, Emma Sager

Senior Honors Theses

This paper aims to explore the application of small-scale desalination systems to provide clean water in the wake of marine natural disasters. A lack of clean water is a devastating impact of many natural disasters. Desalination technologies, both thermal and membrane, show potential for being scaled down and self-powered by renewable energy. Desalination can transform ocean water and contaminated drinking water with a high salt content into drinkable, usable water. While these techniques are not perfected, and the solution to a need for clean water is multifaceted, desalination shows potential. Through further research and ever-advancing technology, small-scale desalination could develop …


Energy-Specific Greenhouse Gas Emissions Measurements From 2-Stroke Marine Diesel Engine Using Liquefied Natural Gas, Kang-Ki Lee, Wilfried Hochegger, Alessandro Schonborn 2023 AVL List GmbH

Energy-Specific Greenhouse Gas Emissions Measurements From 2-Stroke Marine Diesel Engine Using Liquefied Natural Gas, Kang-Ki Lee, Wilfried Hochegger, Alessandro Schonborn

Articles

This study reports the energy specific air emissions from a diesel-cycle high pressure injection dual fuel engine for operation on liquefied natural gas and heavy fuel oil. An experiment at sea was performed onboard a bulk carrier during commercial voyages, to measure the efficiency of the engine and to measure air emissions relevant to air pollution and climate impact for operation on both fuels. The measurements showed that the energy conversion efficiency of the engine was higher for operation on liquefied natural gas because its lower NOx emissions permitted the use of a higher effective compression ratio whilst meeting the …


Wind-Wave Misalignment Effects On Multiline Anchor Systems For Floating Offshore Wind Turbines, Doron T. Rose 2023 University of Massachusetts Amherst

Wind-Wave Misalignment Effects On Multiline Anchor Systems For Floating Offshore Wind Turbines, Doron T. Rose

Masters Theses

Multiline anchors are a novel way to reduce the cost of arrays of floating offshore wind turbines (FOWTs), but their behavior is not yet fully understood. Through metocean characterization and dynamic simulations, this thesis investigates the effects of wind-wave misalignment on multiline anchor systems. Four coastal U.S. sites are characterized in order to develop IEC design load cases (DLCs) and analyze real-world misaligned conditions. Stonewall Bank, Oregon showed the highest 500-year extreme wave height, at 16.6 m, while Virginia Beach, Virginia showed the highest 500-year wind speed, at 56.8 m/s. Misalignment probability distributions, at all sites, are found to converge …


Assessing High Dynamic Range Imagery Performance For Object Detection In Maritime Environments, Erasmo Landaeta 2023 Embry-Riddle Aeronautical University

Assessing High Dynamic Range Imagery Performance For Object Detection In Maritime Environments, Erasmo Landaeta

Doctoral Dissertations and Master's Theses

The field of autonomous robotics has benefited from the implementation of convolutional neural networks in vision-based situational awareness. These strategies help identify surface obstacles and nearby vessels. This study proposes the introduction of high dynamic range cameras on autonomous surface vessels because these cameras capture images at different levels of exposure revealing more detail than fixed exposure cameras. To see if this introduction will be beneficial for autonomous vessels this research will create a dataset of labeled high dynamic range images and single exposure images, then train object detection networks with these datasets to compare the performance of these networks. …


A Study On Scaling Floating Offshore Wind Turbine Geometry And Hydrostatics With Increasing Turbine Size, Samuel Davis 2023 University of Maine - Main

A Study On Scaling Floating Offshore Wind Turbine Geometry And Hydrostatics With Increasing Turbine Size, Samuel Davis

Honors College

Floating offshore wind offers a clean and sustainable alternative to fossil fuels for the future of energy production. In Maine in particular, there is a great opportunity to take advantage of the wind resource off the coast and become a global leader in offshore wind. With the Maine coastal waters being too deep for fixed-bottom turbine structures, floating platforms that support the turbines have the opportunity to gain traction as the technology matures. As wind turbines increase in size and capacity, the floating hulls must also increase in size. The research presented in this thesis aimed to calculate and examine …


Effects Of Various Dietary Carbohydrate Sources On The Growth Performance And Body Composition Of The Dog Conch, Laevistrombus Canarium, Jen-Hong Chu 2023 Department of Aquatic Biosciences, National Chiayi University, Chiayi, 600, Taiwan

Effects Of Various Dietary Carbohydrate Sources On The Growth Performance And Body Composition Of The Dog Conch, Laevistrombus Canarium, Jen-Hong Chu

Journal of Marine Science and Technology

This study investigates the effects of dietary supplementation with various carbohydrate sources on the growth and dietary nutrient utilization efficiency of a 0.72-g dog conch, Laevistrombus canarium. Five treatment diets had supplementation with alpha-starch (Sta), dextrin (Dex), pullulan gum (Pg), xanthan gum (Xg), and carboxymethyl cellulose (CMC). At the end of the feeding trial, the best growth performance (weight gain, 442.23%) and diet efficiency (protein efficiency ratio, 1.25, and feed conversion ratio [FCR], 2.04) were exhibited by the dog conch fed the Sta diet, whereas the lowest growth performance was observed in the dog conch fed the Xg and CMC …


Cost Advantages Of Far East/Europe Trunk Route Deployment With Port Selection In East Asia, Tai Hui-Huang, Chang Chin-Wei 2023 Department of Shipping and Transportation Management, Dean of Marine Science and Technology, National Kaohsiung University of Science and Technology, Taiwan

Cost Advantages Of Far East/Europe Trunk Route Deployment With Port Selection In East Asia, Tai Hui-Huang, Chang Chin-Wei

Journal of Marine Science and Technology

To cater to the gradually increasing sizes of ships, several traditional container ports in East Asia built deep-water wharves to attract shipping carriers to berth, a decision that is considered highly reasonable because it allows for shipping carriers to gain a cost advantage. For traditional Far East/Europe (F/E) trunk routes, shipping carriers must deploy vessels that are large enough at hub ports to maintain low transshipment costs. However, for a port to attract shipping carriers, it should be able to first meet the cargo demand of these carriers. The port would also need to improve the loading ratio to enjoy …


Influence Of Vacuum Condition On Rapid Chloride Migration (Rcm) Test For Chloride Penetration Resistance Of Concrete, Chih-Yen Lin, Chun-Fu Chang, Chung-Chia Yang 2023 Department of Harbor and River Engineering, National Taiwan Ocean University, 2 Pei-Ning Road, Keelung 20224, Taiwan

Influence Of Vacuum Condition On Rapid Chloride Migration (Rcm) Test For Chloride Penetration Resistance Of Concrete, Chih-Yen Lin, Chun-Fu Chang, Chung-Chia Yang

Journal of Marine Science and Technology

NT Build 492 regulates that the pressure be set at 7.5–37.5 torr and be maintained for 3 h for vacuum processing. This large range of acceptable vacuum pressure is awkward for research, and 3 h of pump-down time may be excessive. In this study, vacuum conditions were divided into vacuum pressure and pump-down time groups: various vacuum pressures and pump-down times were used to preprocess specimens to explore the effect of vacuum conditions on the RCM test. The salt ponding test was also conducted to identify the optimal vacuum conditions. It is shown that the relationship between vacuum pressure and …


Exhaust Noise Elimination Using Silencers Fortified With Perforated Tubes, Extended Tubes, Penetrable Resin Inlet And Orifice Plate, Min-Chie Chiu, Ho-Chih Cheng 2023 Department of Mechanical and Materials Engineering, Tatung University, ROC

Exhaust Noise Elimination Using Silencers Fortified With Perforated Tubes, Extended Tubes, Penetrable Resin Inlet And Orifice Plate, Min-Chie Chiu, Ho-Chih Cheng

Journal of Marine Science and Technology

Pneumatic equipment in marine diesel engine and associated piping system often emit extremely high level of noises when releasing pressure. Concerning the crew’s hearing health, discovering an efficient noise silencing device becomes essential. A silencer fortified with extended tubes, perforated tubes, orifice plate, and penetrable resin inlet is presented in order to competently dampen the blown-up noises. A simplified objective function by means of FEM, Artificial Neural Networks (ANNs), and a Genetic Algorithm (GA) is established to enable the numerical calculation when using a finite element method. Three silencer designs, silencer A (with element A, a penetrable resin inlet), B …


Deep Learning–Based, Oceantdlx Sea Ice Detection Model For Sar Image, LIU Lin, LI Wanwu, LI Hang, SUN Yi 2023 Shandong University of Science and Technology, Qingdao, China.

Deep Learning–Based, Oceantdlx Sea Ice Detection Model For Sar Image, Liu Lin, Li Wanwu, Li Hang, Sun Yi

Journal of Marine Science and Technology

This study constructs four deep-learning OceanTDLx series models and uses a WinR-AdaGrad gradient descent algorithm to train and optimize the constructed models. Through an analysis of the loss, accuracy, and time consumption of the four models (i.e., OceanTDL2, OceanTDL3, OceanTDL5 and OceanTDL8), we reveal that the models’ performance does not improve when the number of layers is increased and that OceanTDL5 provides the optimal performance. OceanTDL5 is compared with OceanTDA9 (a model that we previously constructed), and the curves for training loss_batch and training accuracy_batch indicate that OceanTDL5 is more suitable than OceanTDA9 for detecting distributed targets, particularly semi-melted sea …


Application Of Unmanned Aerial Vehicle–Based Infrared Images In Determining Characteristics Of Sea Surface Temperature Distribution, Hsing-Yu Wang, Hui-Ming Fang, Yun-Chih Chiang 2023 Assistant Professor, Department of Shipping Technology, College of Maritime, National Kaohsiung University of Science and Technology

Application Of Unmanned Aerial Vehicle–Based Infrared Images In Determining Characteristics Of Sea Surface Temperature Distribution, Hsing-Yu Wang, Hui-Ming Fang, Yun-Chih Chiang

Journal of Marine Science and Technology

This study investigated the temperature field of a body of water by using rotary-wing unmanned aerial vehicles (DJI Mavic 2 Enterprise Dual) comprising visible light and infrared cameras to determine sea temperature distribution. With a flight height of 150 m, image overlap of 80%, and image resolution of 4.75 cm/pixel, the proposed method was more effective than the conventional portable conductivity–temperature–depth device in rapidly measuring sea surface temperature and determining sea temperature distribution. The discharged heated water of the Hoping Power Plant traveled 100–330 m from the wastewater outfall and then gradually diffused in the range of 100–490 m before …


Combustion Of Scrap Waste Tires Of A Cogeneration Plant, Chin-Ko Yeh, Rong-Hua Yeh 2023 Department of Marine Engineering, National Kaohsiung University of Science and Technology, Taiwan, R.O.C

Combustion Of Scrap Waste Tires Of A Cogeneration Plant, Chin-Ko Yeh, Rong-Hua Yeh

Journal of Marine Science and Technology

Various fuels can be used in circulating fluidized bed (CFB) boilers. In this study, the thermal and economic performance was investigated for three CFB fuels—heavy fuel oil, coal, and waste tire scraps—used in a cogeneration plant. The plant comprised a CFB boiler, a single-cylinder steam-extraction turbine, and a generator. Tire scrap combustion generated the most power per ton during peak hours: approximately 27.5% more than that generated using heavy oil and 42.3% more than when coal was employed; it also resulted in higher boiler efficiency during peak operation than coal (1.2% higher) or heavy oil (12.6% higher). The net plant …


Freespan Analysis For Subsea Pipeline Integrity Management Strategy, Nurul Hadi, Muhammad Helmi, Edo Cathaputra, Dedi Priadi, Donanta Dhaneswara 2023 Universitas Indonesia

Freespan Analysis For Subsea Pipeline Integrity Management Strategy, Nurul Hadi, Muhammad Helmi, Edo Cathaputra, Dedi Priadi, Donanta Dhaneswara

Journal of Materials Exploration and Findings (JMEF)

Abstract. Over a rough seabed or on seabed subject to scour, freespans can occur when contact between a subsea pipeline and the seabed is lost over an acceptable distance. When this exceeds the allowable freespan length, design stresses can be exceeded, and a vortex induced vibration (VIV) response can be initiated, resulting in the risk of fatigue failure. If this is not predicted and controlled properly, it will affect pipeline integrity, leading to expensive rectification and intervention work. Freespan analysis consisted primarily of a screening check in which the as-found freespans from Remotely Operated Vehicle (ROV) or multibeam Side …


Interrogating The State Of Application Of Technology Within The Malawi Maritime Force As Maritime Expression : A Task-Technology Fit Approach, Gift William Kamwendo 2023 World Maritime University

Interrogating The State Of Application Of Technology Within The Malawi Maritime Force As Maritime Expression : A Task-Technology Fit Approach, Gift William Kamwendo

World Maritime University Dissertations

No abstract provided.


New Hampshire Volunteer Beach Profile Monitoring Program (Vbpmp): Implementation, Field Methods, And Data Processing, Larry G. Ward, Rachel C. Morrison, Alyson Eberhardt, Wellsley Costello 2023 University of New Hampshire, Durham

New Hampshire Volunteer Beach Profile Monitoring Program (Vbpmp): Implementation, Field Methods, And Data Processing, Larry G. Ward, Rachel C. Morrison, Alyson Eberhardt, Wellsley Costello

New Hampshire Sea Grant

The New Hampshire (NH) Volunteer Beach Profiling Monitoring Program (VBPMP) monitors beach elevation profiles at multiple stations along the NH Atlantic coast on a near-monthly basis using the Emery method. The program grew from three monitoring stations in 2016-2017 to thirteen stations across six beaches in 2018, with an additional station added in 2022. The overarching goal of the VBPMP is to assess the stability of New Hampshire’s Atlantic beaches over multiple years to determine seasonal changes and long-term trends using citizen science methods. Included in the assessment of beach stability are erosional or accretional trends, response to storms, and …


Numerical Analysis Of Silencer With A Coiled Tube And Straight Perforated Tube Using Fem, Min-Chie Chiu, Ho-Chih Cheng 2023 Department of Mechanicaland Materials Engineering, Tatung University, ROC.

Numerical Analysis Of Silencer With A Coiled Tube And Straight Perforated Tube Using Fem, Min-Chie Chiu, Ho-Chih Cheng

Journal of Marine Science and Technology

Marine diesel engine is essential on a ship, but emits extremely loud noise harmful to human hearing. Therefore, it is mandatory to use silencers to reduce the venting noise of the marine diesel engine. An advanced silencer with a new acoustical element of a curved tube, along with perforated holes, is presented to suppress the noise wave. To predict the silencer's acoustical performance for high-order waves, a finite element model was built using COMSOL. The influence of the silencer's noise reduction ability was investigated by exploring sensitivity using acoustical simulations on COMSOL, regarding the silencer's geometric factors. The results proved …


Abundance And Distribution Of Fish Larvae In The Central Coast Of The Algerian Sea, ETSOURI Mohamed, KHAMES Ghollame Ellah Yacine, SERIDJI Rabea 2023 National Center for Research and Development of Fisheries and Aquaculture (CNRDPA)

Abundance And Distribution Of Fish Larvae In The Central Coast Of The Algerian Sea, Etsouri Mohamed, Khames Ghollame Ellah Yacine, Seridji Rabea

Journal of Marine Science and Technology

This study was conducted on a seasonal basis in five (5) stations along the central Algerian coast between April 2013 and April 2014 aboard professional fishing boats. Horizontal plankton tows with a WP2-type net were used to collect ichthyoplankton samples. At each station, temperature, salinity, and chlorophyll-a levels were measured. We identified the larvae of 18 species from 11 different families by sorting ichthyoplankton (Clupeidae, Engraulidae, Gobidae, Gonostomatidae, Mugilidae, Myctophidae, Scombridae, Sparidae, Carangidae, Labridae, Blennidae). Redundancy analysis (RDA) was used to determine the relationship between the abundance of harvested larvae and environmental variables. The results show a clear dominance of …


Predefined-Time Neural Sliding Mode Control Based Trajectory Tracking Of Autonomous Surface Vehicle, Han Xue, Shulin Li 2023 College of Navigation, Jimei University, Xiamen 361021, Fujian,China

Predefined-Time Neural Sliding Mode Control Based Trajectory Tracking Of Autonomous Surface Vehicle, Han Xue, Shulin Li

Journal of Marine Science and Technology

With the progress and development of modern industry, it is urgent to develop a more general and mature predefined time control theory system for uncertain nonlinear systems and apply it to practical engineering systems. Therefore, a novel predefined-time sliding mode control is designed to improve the slow convergence speed of asymptotically convergent controllers and finite-time convergent controllers affected by the initial state of the system. The proposed control approach is proved to converge from the initial value to the balance position using Jensen's inequality and Liapunov theorem. The proposed control method can deal with the ship motion system having six …


Inventory Management In Supply Chains With Consideration Of Transportation And Green Technology Cost Under Progressive Carbon Taxation, Ming-Feng Yang, Min-Der Ko, Hung-Jen Tu, Mengru Tu, Jun-Yuan Kuo, Yen-Ting Chao, Shang-Wei Shih 2023 Department of Transportation Science, National Taiwan Ocean University, Taiwan, ROC

Inventory Management In Supply Chains With Consideration Of Transportation And Green Technology Cost Under Progressive Carbon Taxation, Ming-Feng Yang, Min-Der Ko, Hung-Jen Tu, Mengru Tu, Jun-Yuan Kuo, Yen-Ting Chao, Shang-Wei Shih

Journal of Marine Science and Technology

Reducing carbon emissions is an important issue in the global supply chain. Governments have formulated different carbon policies to achieve carbon neutrality or emission reduction, in particular, the carbon tax as a policy provides greater certainty about the potential cost to emitters. The Taiwan government is expected to implement the carbon tax policy in 2024 and does not rule out the inclusion of a progressive mechanism which is more effective than a single carbon tax in curbing high carbon emissions Recent studies have also confirmed that a high level and complete carbon tax could encourage companies to invest in green …


Genetic Algorithm For Solving A Just-In-Time Inventory Model With Imperfect Rework Implemented In A Serial Multi-Echelon System, Hsien-Chung Tsao, Cheng-Chi Chung, Hsuan-Shih Lee, Chih-Ping Lin, Yan-Yun Tu, Ssu-Chi Lin 2023 Department of Shipping and Transportation Management, National Taiwan Ocean University, Taiwan

Genetic Algorithm For Solving A Just-In-Time Inventory Model With Imperfect Rework Implemented In A Serial Multi-Echelon System, Hsien-Chung Tsao, Cheng-Chi Chung, Hsuan-Shih Lee, Chih-Ping Lin, Yan-Yun Tu, Ssu-Chi Lin

Journal of Marine Science and Technology

As global industrial competition intensifies, enterprises can achieve substantial competitive advantages in the supply chain management environment by promptly meeting customer demands and efficiently reducing both supply and demand costs. This paper proposes an inventory model for supply chain optimization that considers uncertain delivery lead times and defective products. Solving the model requires solving a nonlinear mixed-integer problem, which traditionally requires considerable time. Solutions to nondeterministic polynomial-time hard problems with high complexity and difficulty are often obtained using heuristic algorithms. Among these algorithms, genetic algorithms have high efficiency and quality. Therefore, we employed a genetic algorithm to solve the proposed …


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