Physical Sciences and Mathematics Commons^™

Application Of Semantic Segmentation To An Automatic Target Recognition Problem, Bruce W. Rush Jr.

College of Graduate Studies: Theses & Dissertations

Synthetic Aperture Radar (SAR) is an active remote sensing system commonly used in aerial reconnaissance. SAR penetrates cloud cover and vegetation by recording reflected energy pulses. The resulting information content is difficult to interpret due to vast clutter data and sparse target data. The time-consuming process of analyzing SAR imagery can be greatly reduced by implementing an Automatic Target Recognition (ATR) algorithm. Convolutional Neural Networks (CNN) are capable of extracting identification features from SAR data content. Further research in this field indicates that high performing models are insufficiently robust due to high clutter correlation among classes in the Moving and …

Response Of Galactic Disks To Dark Matter Halo Triaxiality, Alex J. Hutton

College of Graduate Studies: Theses & Dissertations

In this study we examine the influence of dark matter halo triaxiality on the evolution of galactic disks. We do this by running a series of collisionless N-body models. In a first set of models we place the galactic disk within an oblate halo at various orientations and examine the resulting evolution. In our second set we construct fully self-consistent models of a stellar disk embedded within a spherical halo, with an impacting external dark matter dwarf galaxy. After evolving the simulations for a Hubble time, we examine the disk orientation and warping along with other quantities such as bar …

Majority Decision Using Top-Performing Neural Networks Models For Improved Credit Risk Prediction, Vincent Dey

College of Graduate Studies: Theses & Dissertations

Credit risk prediction remains both a challenging and high-interest problem due to the inherently unbalanced nature of financial datasets and the continuous drive for higher pre- dictive precision. In this work, I build upon previous advancements in credit risk modeling and introduce an ensemble-based Artificial Neural Network (ANN) architecture designed to enhance classification performance. By leveraging a selective ensemble of decision net- works, this approach not only improves prediction accuracy but also mitigates the chal- lenges posed by imbalanced data distributions. While the primary focus is on credit risk prediction, my analysis demonstrates that the proposed model can be effectively …

Applying The Lagrangian Variational Method To Atom Interferometry, Jeffrey W. Heward

College of Graduate Studies: Theses & Dissertations

Atom interferometry in Bose-Einstein condensate systems has emerged as a promising technique for precision metrology. The dynamics of these systems are well-described by the Gross-Pitaevskii equation (GPE), but direct numerical solution of this equation is infeasible for realistic systems. We use the Lagrangian Variational Method (LVM) to approximate solutions of the GPE in 1D and 3D, and we compare the LVM results to the exact solutions. We also present 3D LVM results for a case where numerical solution of the GPE is infeasible.

Towards A Baker-Campbell-Hausdorff Theorem In Positive Characteristic, Nikolas A. Koutroulakis

College of Graduate Studies: Theses & Dissertations

We investigate whether there is an analog of the Baker-Campbell-Hausdorff (BCH) theorem for Lie algebras over fields of positive characteristic. We begin by introducing the proof of the BCH formula in characteristic zero. We then introduce the Artin-Hasse exponential and show that it is $p$-integral. Our main result provides sufficient conditions under which a BCH-type formula exists for the Artin-Hasse exponential in positive characteristic. Additionally, we derive a formula for computing an inverse of the Artin-Hasse exponential.

Microbial Community Stabilization By Restored Oyster Reefs: Implications For Blue Carbon Storage, Natalie Boydstun

College of Graduate Studies: Theses & Dissertations

Coastal ecosystems provide critical carbon sequestration services, yet the microbial mechanisms underlying carbon storage remain poorly understood, particularly in non-vegetated habitats. This study investigated whether restored oyster reefs (Crassostrea virginica) enhance sediment carbon storage potential by stabilizing microbial communities and promoting efficient organic matter processing. I hypothesized that reef-mediated sediment stabilization and organic deposition would create conditions favoring microbial degradation of complex carbon compounds into stable soil organic matter, ultimately supporting anaerobic carbon storage. To test this, I compared sediment biogeochemistry, enzyme activity, and microbial community structure between three restored oyster reef sites and two unstructured control sites …

Investigation Of A Busemann Intake At Negative Angle Of Attack, Mark E. Noftz, Andrew N. Bustard, Nicholas J. Bisek, Thomas J. Juliano, Joseph S. Jewell

Publications

A high-speed, shape-transitioned, inward-turning intake was tested in Purdue’s Boeing/AFOSR Mach 6 Quiet Tunnel. The inlet model, called the Indiana Inlet (INlet), had a total contraction ratio of 4.68:1 and a design point of Mach 6 at 0° angle of attack. The model was outfitted with a suite of high-frequency pressure transducers, and the external flowfield was imaged with high-speed schlieren photography. The INlet was tested under low freestream disturbance levels for a variety of freestream unit Reynolds numbers and at-4° angle of attack. An unsteady shockwave near the leading edge of the inlet forebody, indicative of boundary layer separation, …

Information Retrieval In The Age Of Generative Ai: A Mismatch That Matters, Alex Zhang

Faculty Scholarship

This short piece explores a widespread and yet underexamined or even overlooked misconception, that is, large language models (LLMs) function like traditional legal research databases. They do not. As a matter of fact, information retrieval from databases functions very differently from LLMs in terms of inputs, retrieval processes, and outputs. These differences have significant implications for transparency, traceability, and overall effectiveness in AI-driven legal research. Without intentional oversight and adaption, these changes could profoundly affect how we develop research skills and a cumulative knowledge base, both of which are essential skills for lifelong learning in the legal field.

This article …

Berkeley Pit And Discharge Pilot Project Quarterly Pilot Project Report Third Quarter 2024, Atlantic Richfield Company, Mark Thompson

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Numerical Simulation Of The Fracture Resistance Of A Flame Deflector Under Impact And High Temperature By Using The Extended Finite-Element Method, Guangzhong Liu, Yuqing Feng, Tong Lin, Zhixin Xiong, Zhenting Chen

Journal of Marine Science and Technology–Taiwan

During the launch of rockets at sea, the flame deflector of the launch platform is subject to transient impact loads and high temperatures, which can result in the fracturing of the flame deflector, thereby endangering the platform and launch safety. In this study, dynamic crack propagation in a flame deflector under the aforementioned conditions was numerically investigated using the extended finite-element method (XFEM). The bulk of the flame deflector was modeled using shell elements, the local area in which the crack evolves was modeled using solid elements, and discontinuities were modeled using enrichment functions in the XFEM. The degrees of …

Overseas Agent Selection For International Logistics Companies: A Case Study, Hung-Ta Lin, Hua-An Lu

Journal of Marine Science and Technology–Taiwan

International logistics companies (ILCs) have aggressively participated in the supply chain systems of production industries as part of global trade development. They have adopted diversified and multinational models by expanding their overseas services to align with the various characteristics of regional economic patterns. Assigning specific local agents for their forwarding operations has been one of the key strategies for overseas services. Notably, the performance of these selected agents has significantly influenced service quality in their respective regions. In collaboration with the top management of an ILC, this study proposes an evaluation framework comprising 4 criteria and 16 subcriteria for selecting …

Cfrp Retrofitting For Enhancing Damping In Cushion Mounts For Marine Applications, Chih-Lung Hou, Guang-Min Luo, Sheng-Yuan Chen

Journal of Marine Science and Technology–Taiwan

Reducing vibration transmission and dynamic response is critical for data processing devices, precision instruments, and machinery in environments with frequent shocks, such as naval applications. These devices are often mounted to ships with cushion mounts. This study presents a cost-effective and rapid method for retrofitting mounts with carbon fiber reinforced polymers; the method greatly improved damping and effectively reduced vibration transmission. Specimens were produced and subjected to experimental modal analysis, and finite element models were developed for comparison. The frequency response functions and modes of the structural components from both methods were compared to assess the improvement in the damping …

Application Of Genetic Algorithm In Container Vessel Stowage Planning With Carbon Tax Considerations, Ming-Feng Yang, Wei-Hao Su, Ko-Meng Hu, Yu-Hsuan Li

Journal of Marine Science and Technology–Taiwan

This study developed a method for optimizing stowage planning for container vessels, a crucial aspect of international trade logistics. Over 80% of global trade depends on containerized transportation; thus, effective stowage planning is essential for minimizing transportation costs and enhancing operational efficiency. In the proposed hybrid optimization approach, integer programming is combined with a genetic algorithm to generate optimal stowage plans. The key factors considered in this method include load capacity limits, stacking constraints, and carbon tax regulations. The proposed method involves maximizing space utilization while minimizing logistics costs, with particular emphasis on reducing port dwell times. The findings of …

Research On Multi-Ship Collision Avoidance Decision-Making Based On Improved Velocity Obstacle Method Using Dynamic Elliptical Ship Domains, Tang Xinwei, Li Weifeng

Journal of Marine Science and Technology–Taiwan

The velocity obstacle method offers collision avoidance solutions for critical multi-ship encounter scenarios. This thesis introduces a Reciprocal Velocity Obstacle (RVO) approach based on dynamic elliptical ship domains for multi-ship collision avoidance. Initially, the concept of dynamic elliptical ship domains is presented, building upon the original static elliptical ship domain Velocity Obstacle (VO) method. Subsequently, multi-ship encounter scenarios are simulated in both virtual environments and real nautical charts, comparing the two methods. The analysis results demonstrate the improved method's excellent performance in both cases, underscoring its advantages. This research provides more effective collision avoidance strategies for multi-ship encounters.

Exploring The Red Sea Crisis’S Supply Chain Disruption Impacts On The Shipping Industry, Po-Hsing Tseng, Nick Pilcher

Journal of Marine Science and Technology–Taiwan

Since October 7, 2023, the Houthi militia in Yemen has continuously attacked Israel and its nearby ships in the Red Sea. This crisis has impacted on global ship operations, freight rates, and shipping networks, since this conflict seriously affects the international trade between Europe and Asia and brings many unpredictable butterfly effects (e.g. supply chain disruption, and high transportation costs in shipping and air cargo). This papero explores its impact on the supply chain and suggests potential solutions;, and to consider perceptions on who should be responsible for the crisis, and who will actually shoulder the responsibility for the crisis. …

Dna Barcoding In Species Identification Of Flying Fish (Exocoetidae) And Halfbeaks (Hemiramphidae) Larvae: A Comparative Study Of The Database Over A Decade, Hui-Ling Ko, Kwang-Tsao Shao, Ching-Yi Chen, Yen-Wei Chang

Journal of Marine Science and Technology–Taiwan

The families Exocoetidae and Hemiramphidae comprise migratory species, whose identification based on their external morphological characteristics can be challenging because of their similarities. DNA barcoding has been used in taxonomic and evolutionary studies to address these issues. The morphological characteristics of fish larvae change rapidly and often lack distinctive features, posing a challenge for species-level identification. This study used DNA barcoding to identify flying fish and half-beaked larvae. Using plankton nets, sampling was conducted seasonally between 2010 and 2013 in Nanwan, Taiwan. A total of 903 individuals were collected, of which 111 were identified as flying and half-beaked fish based …

Operational Risk Evaluation Of Oil Tankers Via Multivariate Gaidai Reliability Framework Incorporating Memory Effects, Oleg Gaidai, Shicheng He, Jinlu Sheng, Yan Zhu, Alaa Elsayed, Mahmoud El-Wazery

Journal of Marine Science and Technology–Taiwan

The retreat of Arctic Sea ice may exert a major impact on economy，potentially transforming the nature of commerce between Asia, Europe, and the Americas. Projections indicate a 40% reduction in transit distance and a 30% decrease in voyage time between Europe and northwest Asia compared to traditional routes such as the Suez Canal. However, even during summer navigation, fragmented floating ice persists, generating stochastic ice loads on vessel bows and hulls through complex ship-to-ice interaction. For structural design, statistical extrapolation methods are required to accurately assess excessive areal bow/hull stresses. This study proposes a novel multi-modal structural damage risk assessment …

Key Steering Characteristics For Training Remote Operators Of Maritime Autonomous Surface Ships In Collision Avoidance, Soyeong Lee, Ik-Hyun Youn

Journal of Marine Science and Technology–Taiwan

Maritime Autonomous Surface Ships (MASS) require remote operators (ROs) who need to be trained in collision avoidance (CA) maneuvers. In order to develop a training system, this study investigated differences in the steering characteristics of expert and novice navigators such as the timing of the initial rudder operation, rudder angle at a relative bearing 0°, heading at the maximum rate of turn to starboard, and, heading at the closest point of approach. The experts exhibited relatively consistent and controlled steering patterns characterized by earlier rudder adjustments and smoother heading transitions while novices demonstrated delayed reactions and greater variability in heading …

Subsurface Origin Of Tex86 Signals Revealed By Cross-Seasonal Gdgt Distributions In Suspended Particulate And Sediment Samples From The Southern East China Sea, Hung-Lin Tsai, Da-Chen Lin

Journal of Marine Science and Technology–Taiwan

The TetraEther indeX of 86 carbon atoms (TEX₈₆) proxy, which is based on isoprenoid glycerol dialkyl glycerol tetraethers (isoGDGTs) produced by Thaumarchaeota in marine environments, is widely used to reconstruct past sea surface temperatures (SSTs). However, evidence suggests that this proxy often instead reflects subsurface conditions, particularly in dynamic marginal seas. Therefore, we conducted a cross-seasonal study of glycerol dialkyl glycerol tetraether (GDGT) distributions in the southern East China Sea (ECS), which is characterized by strong monsoonal and current-driven hydrographic variability. We analyzed surface sediments and the high-resolution vertical profiles of suspended particulate matter (SPM) collected from 2016 …

The Current Status And Challenges Of Efforts To Generate Blue Carbon Credits In Okinawa Prefecture, Takashi Tamura, Wei-Chung Chen, Takafumi Sasaki

Journal of Marine Science and Technology–Taiwan

In Okinawa Prefecture, the Mozuku aquaculture industry is keen on establishing Blue Carbon Credits. This enthusiasm stems from various perspectives, including climate change mitigation, improvement of fishing grounds, industry maintenance, and enhancement of fishing ground surveillance functions. However, the industry faces several challenges. One significant challenge is the lack of a clear remaining coefficient for Mozuku, which complicates the creation of credits. Additionally, there is a shortage of manpower within the fisheries cooperative, further exacerbating the problem. To address these challenges, it is crucial to secure human resources that can promote system understanding and establish a financial base for undertaking …

In-Situ And Laboratory Sound Velocities Of Unconsolidated Sediments In The Western South Korea Plateau Of The East Sea, Kiju Park, Gil Young Kim, Yuri Kim, Bo Yeon Yi, Nyeon Keon Kang, Gwang Soo Lee

Journal of Marine Science and Technology–Taiwan

The in-situ velocity of unconsolidated shelf sediments in the western South Korea Plateau of the East Sea was directly measured using the Korea Institute of Geoscience and Mineral Resources (KIGAM) Seafloor Acoustic Probe. Physical properties, including laboratory velocity, were also measured for core samples collected from the same location. The laboratory measurements were conducted at a temperature of 23℃ and under atmospheric pressure. Owing to the in-situ temperature and pressure (0.5–1.5℃ and 100–180 atm, respectively) at the sampling site, the laboratory velocity was adjusted to the in-situ conditions. In addition, a comparison with a theoretical prediction model (Biot-Stoll model) was …

Diel Variations In Abundance Of Viral, Picoplankton, And Nanoplankton In Coastal Waters Of Taiwan In Spring, Patrichka Wei-Yi Chen, Madeline Olivia, Vladimir Mukhanov, Ufimtseva Margarita, Liashko Tatiana, Sakhon Evgenii, Supriyadi Supriyadi, Intan Dwi Puspitasari, Arpita Ghosh, An-Yi Tsai

Journal of Marine Science and Technology–Taiwan

The diel variations of viruses (< 0.2 μm), picoplankton (0.2-2 μm; heterotrophic bacteria, Synechococcus spp., and picoeukaryotes), and nanoflagellates (2-20 μm; heterotrophic and pigmented nanoflagellates) were examined for 2 days with approximately 4 h of temporal sampling in the spring of 2024 in coastal surface waters of the subtropical western Pacific. The abundance of bacteria did not follow a consistent diel pattern, and viral abundance was positively correlated with bacterial abundance. Synechococcus spp. was found to grow during the light period and with peak abundance at night, exhibiting a remarkably diel pattern; however, the pattern was opposite in picoeukaryotes. In the size-fractionation experiments, after 32 h of …

New Insights Into Decapod Chemical Communication: A Focus On The Hydrothermal Vent Crab Xenograpsus Testudinatus, Jishnu Panamoly Ayyappan, Mark June S. Consigna, Li-Chun Tseng, Jiang-Shiou Hwang

Journal of Marine Science and Technology–Taiwan

Chemical communication in decapod crustaceans has been extensively studied for over 150 years, with most of the research focusing on sex pheromones. These crustaceans inhabit chemically complex environments and rely on diverse chemical signals for essential behaviors such as mate recognition, predator avoidance, and social interaction. This review synthesizes key findings from studies on shrimp, crayfish, lobsters, and crabs, the most well-documented taxa in crustacean chemical ecology. Various appendages, including the first and second antennae, mouthparts, and walking legs, are involved in chemosensory detection. Special emphasis is placed on chemical communication in extreme environments such as hydrothermal vents (HVs), with …

Apply Cluster Analysis To Improve Interpretation Of Ert Images, Yin-Chun Hung, Yu-Xiang Zhao

Journal of Marine Science and Technology–Taiwan

The completeness and accuracy of collecting and investigating geotechnical and marine engineering geological conditions are key to the success or failure of engineering development. Traditional marine engineering and geotechnical surveys often require the assistance of geophysical methods to fully present the geological conditions. Electrical Resistivity Tomography (ERT) is an advanced geophysical method that produces accurate cross-sections of underground resistivity. Although 2D ERT has been widely used in geotechnical engineering and marine engineering, many uncertainties remain hidden behind the vivid and colorful resistivity profiles. To apply 2D ERT profiles effectively in geotechnical and marine geological surveys and monitoring, it is essential …

Geo-Chemical Fractionations Of Phosphorus In Sediments Of Thuy Trieu Lagoon And Cam Ranh Bay, Vietnam, Phu H. Le, Ngoc H. Pham, Dung T. Le, Tuan Linh T. Vo, Binh V. Tran, The V. Ho

Journal of Marine Science and Technology–Taiwan

The geochemical fractions of phosphorus (P) and its bioavailability in sediments of Thuy Trieu Lagoon and Cam Ranh Bay were investigated. Twenty-four surface sediment samples were collected in the dry season (Jun 2024) and the rainy season (Oct 2024). A sequential extraction procedure was applied to identify the phosphorus (P) fractions in sediments, including Exchangeable P (Ex-P), iron-bound P (Fe-P), aluminum-bound P (Al-P), calcium-bound P (Ca-P), and residual P (Res-P). Total P (TP) ranged from 214.9 to 2365.2 µg.g^-1, and the Ca-P fraction was the dominant chemical form in sediments. Based on the results of Pearson correlation and …

Beyond Basic Needs : Exploring The Antecedents And Outcomes Of Seafarers’ Well-Being, Chian Liou, Cheng Kuo Sung, Kimberly Hsiu-Chin Lee, Jiunn Liang Guo

Journal of Marine Science and Technology–Taiwan

Given the importance of seafarers’ mental health and the limited literature on this topic, this study aims to explore the causes and consequences of seafarers’ well-being. A questionnaire survey was conducted, and the data were analyzed using structural equation modeling and hierarchical regression analysis. Consistent with the predictions of the happy and productive worker thesis, this study found that the more satisfied the seafarers are with the shipping company’s seafarer policy, the higher their well-being tends to be, leading to a more positive work attitude. Interestingly, the study found that a company effect is significantly present in this correlation; that …

Empowering Shipping Management Competence With Artificial Intelligence: A Strategic Approach To External Environmental Volatility, Yu-Kai Huang, Cheng-Hsien Hsieh, Chi-Chang Lin, Yu-Tzu Chang, Yu-Chao Cheng

Journal of Marine Science and Technology–Taiwan

The shipping industry is undergoing significant transformation with advancements in artificial intelligence (AI), yet challenges remain in effectively adopting AI technologies. This study addresses the key concerns influencing AI adoption in shipping management. Using the Analytic Hierarchy Process (AHP) integrated with the PEST model, an evaluation framework was developed to assess AI applications in shipping companies. Based on expert input collected through the Delphi method, four constructs and twelve criteria were identified, with the 'Technological' dimension being the most critical. 'Robustness,' 'Costs,' and 'Data quality' emerged as the top factors affecting AI implementation. The framework offers practical insights for shipping …

Comparative Evaluation Of Deep Learning Models For Predicting Skipjack Tuna (Katsuwonus Pelamis) Catch Based On Climatic Factors, Peng Ding, Hui Xu, Xin Zhuang, Yan-Lun Wu, Fengyuan Shen, Yujie Xiao, Jiensi Zhulidezi, Wei-Yu Lee

Journal of Marine Science and Technology–Taiwan

To investigate the impact of climatic factors on skipjack tuna catch, this study collected and analyzed annual global skipjack tuna catch data spanning from 1960 to 2021, along with corresponding monthly data for the key indicator of El Nino events (Niño1+2, Niño3, Niño4, and Niño3.4), the Southern Oscillation Index (SOI), the North Atlantic Oscillation (NAO), the Pacific Decadal Oscillation (PDO), the North Pacific Index (NPI), and the global sea-air temperature anomaly index (dT). The optimal lag years of climatic factors were identified by selecting the maximum absolute cross- correlation coefficients. Subsequently, the predictive performance of LSTM, BiLSTM, and CNN-BiLSTM models …

Effects Of Train-Ship Direct Transshipment On Container Terminal Operational Efficiency And Energy Consumption: From A Scheduling Perspective, Yiying Du, Yaozong Wang, Zhongzhen Yang

Journal of Marine Science and Technology–Taiwan

On-dock rail integration positions terminals as critical hubs for rail-sea transshipment, which necessitates efficient scheduling for rapid container transfers. Given the strict schedules and batch arrival of railway containers, in this study, we propose a train-ship direct transshipment (TSDT) mode to eliminate nonproductive yard rehandling. To comprehensively evaluate the impact of the proposed mode on terminal handling operations, we developed an operational scheduling model for the entire process of the simultaneous loading of yard containers and railway-handling area (RHA) containers. The model comprises two stages. Stage 1 models the pre-reshuffling operations in the yard before loading, and Stage 2 implements …

Key Success Factors In Using The Lifting Method To Construct A Steel Bridge Pylon, Ming-Chao Su, Hui-Ping Tserng

Journal of Marine Science and Technology–Taiwan

Constructing the inclined steel pylon of cable-stayed bridges is challenging because of the pylon’s height, spatial limitations, and safety concerns. To address these challenges, this study developed a modular lifting method that can enhance the efficiency and precision of pylon construction. The proposed method involves using rotation jigs to temporarily assemble the pylon, horizontal positioning on temporary supports, and synchronized lifting through computer-controlled hydraulic systems. Field implementation on a large-span bridge project revealed that compared with the traditional method, the proposed method resulted in higher welding quality, lower risks associated with great-height operations, and a shorter on-site assembly time. The …