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Full-Text Articles in Marine Biology

แบบจำลองเชิงตัวเลขการกระจายและการสะสมตัวของขยะพลาสติกลอยน้ำบริเวณชายฝั่งภาคตะวันออกของประเทศไทย, จิราภา อังศุวรพฤกษ์ Jan 2025

แบบจำลองเชิงตัวเลขการกระจายและการสะสมตัวของขยะพลาสติกลอยน้ำบริเวณชายฝั่งภาคตะวันออกของประเทศไทย, จิราภา อังศุวรพฤกษ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

ขยะทะเลเป็นปัญหาสำคัญที่ส่งผลกระทบต่อสิ่งมีชีวิต ระบบนิเวศ และเศรษฐกิจชายฝั่ง ประเทศไทยเป็นประเทศหนึ่งที่มีการปล่อยขยะลงสู่ทะเลในปริมาณสูง โดยเฉพาะพื้นที่ชายฝั่งภาคตะวันออกของอ่าวไทย ซึ่งเป็นพื้นที่ที่มีการพัฒนาอย่างรวดเร็วทั้งทางด้านอุสาหกรรม การท่องเที่ยว การประมง และการตั้งถิ่นฐานตามแนวชายฝั่ง ปัจจุบันปริมาณขยะในทะเลมีแนวโน้มเพิ่มขึ้นอย่างต่อเนื่อง โดยเฉพาะขยะพลาสติกซึ่งมีคุณสมบัติย่อยสลายยากและมีน้ำหนักเบา ส่งผลให้ขยะสามารถแพร่กระจายและสะสมตัวในบริเวณกว้าง โดยมีกระแสน้ำเป็นปัจจัยสำคัญที่ควบคุมการเคลื่อนที่ ในการศึกษาครั้งนี้มีวัตถุประสงค์เพื่อศึกษารูปแบบการกระจายและการสะสมตัวของขยะพลาสติกที่ลอยอยู่บนผิวน้ำในบริเวณอ่าวไทยฝั่งตะวันออก ภายใต้กระแสน้ำที่ได้รับแรงขับจากน้ำขึ้นน้ำลง ลม และคลื่น โดยใช้แบบจำลองเชิงตัวเลข Delft3D แบบสองมิติ วิธีการศึกษาแบ่งออกเป็น 3 ส่วน คือ (1) การจำลองการไหลเวียนของกระแสน้ำในอ่าวไทยด้วยแบบจำลองอุทกพลศาสตร์ (Delft3D-FLOW) ร่วมกับแบบจำลองคลื่น (Delft3D-WAVE) (2) การจำลองการเคลื่อนที่ของทุ่นลอย (drogue) เพื่อวิเคราะห์จุดปล่อยทุ่นที่มีแนวโน้มเคลื่อนที่เข้าสู่ชายฝั่งด้านตะวันออกของอ่าวไทย โดยพิจารณาแหล่งกำเนิดของขยะที่ปากแม่น้ำในบริเวณอ่าวไทยและประเทศใกล้เคียง และ (3) การจำลองการกระจายตัวและการสะสมตัวของขยะพลาสติกลอยน้ำด้วยแบบจำลองการติดตามอนุภาค (Delft3D-PART) ผลการศึกษาพบว่า การไหลเวียนของกระแสน้ำในอ่าวไทยมีความสอดคล้องกับฤดูมรสุม โดยในช่วงมรสุมตะวันตกเฉียงใต้ กระแสน้ำมีลักษณะการไหลแบบตามเข็มนาฬิกา ส่วนช่วงมรสุมตะวันออกเฉียงเหนือ กระแสน้ำไหลแบบทวนเข็มนาฬิกา และในช่วงเปลี่ยนฤดูมรสุม กระแสน้ำมีลักษณะการไหลที่แปรปรวนและมีกระแสน้ำหมุนวนขนาดเล็ก (gyre) ในหลายพื้นที่ ซึ่งกระแสน้ำจะส่งผลโดยตรงต่อการกระจายและการสะสมตัวของขยะพลาสติกลอยน้ำ โดยขยะที่มีแหล่งกำเนิดจากปากแม่น้ำบริเวณอ่าวไทยตอนในและพื้นที่บางส่วนของอ่าวไทยฝั่งตะวันตก ส่วนใหญ่มีการกระจายตัวอยู่ในบริเวณอ่าวไทยตอนใน และเคลื่อนที่ไปตามแนวชายฝั่งด้านตะวันออก โดยเฉพาะบริเวณจังหวัดชลบุรี ในขณะที่ขยะจากอ่าวไทยฝั่งตะวันออกจะเคลื่อนที่ตามแนวชายฝั่งด้านตะวันออก โดยมีขยะบางส่วนถูกพัดเข้าสู่อ่าวไทยตอนในในช่วงมรสุมตะวันออกเฉียงเหนือ และสำหรับการสะสมตัวของขยะพบว่าขยะที่ถูกปล่อยจากอ่าวไทยตอนในมีการสะสมตัวสูงในบริเวณชายฝั่งจังหวัดชลบุรี ส่วนขยะจากฝั่งตะวันออกจะมีการสะสมตลอดแนวชายฝั่งด้านตะวันออก ขณะที่ขยะจากปากแม่น้ำในประเทศใกล้เคียงพบการกระจายตัวและการสะสมตัวในบริเวณอ่าวไทยน้อยมาก ซึ่งแสดงให้เห็นว่าขยะส่วนใหญ่ที่มีจุดปล่อยจากปากแม่น้ำในอ่าวไทยจะมีการกระจายและการสะสมตัวอยู่ภายในอ่าวไทยเป็นหลัก และมีเพียงบางส่วนที่เคลื่อนที่มาจากพื้นที่นอกอ่าวไทย

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ฮอร์โมนเอกไดสเตียรอยด์ในวงจรการลอกคราบของปูขาว Scylla Paramamosain Estampador, 1949, พีรเดช ใจมั่น Jan 2025

ฮอร์โมนเอกไดสเตียรอยด์ในวงจรการลอกคราบของปูขาว Scylla Paramamosain Estampador, 1949, พีรเดช ใจมั่น

Chulalongkorn University Theses and Dissertations (Chula ETD)

ฮอร์โมนกลุ่มเอกไดสเตียรอยด์ (ecdysteroids) เป็นฮอร์โมนสเตียรอยด์ที่มีบทบาทสำคัญในการควบคุมกระบวนการลอกคราบ การเจริญเติบโต และการพัฒนาในสัตว์ขาปล้อง โดยเฉพาะในกลุ่มครัสเตเชียน การศึกษานี้มีวัตถุประสงค์เพื่อวิเคราะห์ชนิดฮอร์โมนและระดับฮอร์โมนกลุ่ม ecdysteroids ในวงจรการลอกคราบของปูขาว (Scylla paramamosain) โดยเลี้ยงปูในระบบน้ำหมุนเวียนเป็นเวลา 2 เดือน ครอบคลุมวงจรลอกคราบอย่างน้อย 1 รอบ และเก็บตัวอย่างเลือดทุก 2 วัน ปริมาณ 100 µL เพื่อตรวจวัดฮอร์โมน Ecdysone (E), 20-hydroxyecdysone (20-HE) และ Ponasterone A (PoA) ด้วยเทคนิค High Performance Liquid Chromatography (HPLC) ผลการวิเคราะห์พบว่า ฮอร์โมน PoA มีความเข้มข้นสูงในระยะ premolt (445.18 ± 54.64 ng/mL, n=11) มากกว่าระยะ intermolt อย่างมีนัยสำคัญทางสถิติ (78.46 ± 9.9 ng/mL, n=11; p

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‘Who’S Your Daddy?’: Ddradseq Parentage In Broodstock-Offspring Pairs Of Diadema Antillarum In A Population Restoration Initiative, Bianca R. Rosendahl Jan 2025

‘Who’S Your Daddy?’: Ddradseq Parentage In Broodstock-Offspring Pairs Of Diadema Antillarum In A Population Restoration Initiative, Bianca R. Rosendahl

Undergraduate Scholarship and Creative Works

In the early 1980s Diadema antillarum, or the long-spined urchin, was hit by a catastrophic mass mortality event across the western Atlantic and Gulf of Mexico, inclusive of the Florida Keys. The cause of this die-off event was likely triggered by a pathogen or environmental stressor that decimated native populations by up to 98%. The species has not yet fully recovered and is struggling with recruitment success which is why it may benefit from an ex-situ recovery program. In this study, I used single nucleotide polymorphisms (SNPs) to identify genetic variation and analyze parentage in a captive population of …

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Using Post-Supercritical Co2-Assisted Method To Deposit Niep Alloy Coating On The Micro-Arc Oxidation Layer Of Az31 Magnesium Alloy And Its Corrosion Behavior Analysis, Kang-Yu Liao, Hung-Hua Sheu, Ming-Yuan Lin, Ming-Chih Kuo, Po-Hsun Wu, Hung-Bin Lee Jan 2025

Using Post-Supercritical Co2-Assisted Method To Deposit Niep Alloy Coating On The Micro-Arc Oxidation Layer Of Az31 Magnesium Alloy And Its Corrosion Behavior Analysis, Kang-Yu Liao, Hung-Hua Sheu, Ming-Yuan Lin, Ming-Chih Kuo, Po-Hsun Wu, Hung-Bin Lee

Journal of Marine Science and Technology–Taiwan

In this study, a Ni-P alloy coating was deposited on the micro arc oxidation (MAO) layer of AZ31 magnesium alloy to improve its corrosion resistance. The MAO layers were prepared under different operated voltages from 300 to 400 V. The results indicated that the optimize operated parameters for MAO layer is at 350 V, the MAO coatings had the most compact microstructure and superior corrosion resistance. In order to improve the corrosion resistance of MAO coating, this study chose to deposit Ni-P alloy coating on the surface of MAO coating via the post supercritical CO2-assisted electroless plating (PSC-CO …

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The Effect Of Feedback On A Remote Operator’S Maneuvering Control For Mass Remote Navigation Competency, Hyoseon Hwang, Ik-Hyun Youn Jan 2025

The Effect Of Feedback On A Remote Operator’S Maneuvering Control For Mass Remote Navigation Competency, Hyoseon Hwang, Ik-Hyun Youn

Journal of Marine Science and Technology–Taiwan

The rapid advancement of Maritime Autonomous Surface Ships (MASS) technology has highlighted the growing need for Remote Operators (ROs) to manage MASS effectively. ROs possess specialized competencies in areas such as situational awareness, crisis management, and system operation. Despite the introduction of competency-based training and assessment in the maritime sector through the international convention on standards of training, certification, and watchkeeping for seafarers convention, the framework's implementation remains incomplete, particularly in remote operator training for MASS. This study is purpose to identify which competencies improve rapidly with performance feedback and which improve slowly. This study conducted an experiment to quantitatively …

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Evaluation Of Carbon Sequestration In Seagrass Meadows Of Kenting: A Comparative Study With Penghu And Dongsha Island, Zih-Wei Tang, Huei-Fen Chen, Jordi Mahardika Puntu, Ping-Yu Chang, Li Lo, Jian-Jhih Chen, Wen-Chen Chou, Lan-Feng Fan, Ying-Ju Chang Jan 2025

Evaluation Of Carbon Sequestration In Seagrass Meadows Of Kenting: A Comparative Study With Penghu And Dongsha Island, Zih-Wei Tang, Huei-Fen Chen, Jordi Mahardika Puntu, Ping-Yu Chang, Li Lo, Jian-Jhih Chen, Wen-Chen Chou, Lan-Feng Fan, Ying-Ju Chang

Journal of Marine Science and Technology–Taiwan

This study investigates the controlling factors of carbon sequestration (CS) in seagrass bed sediments across three distinct environments in Taiwan: the Kenting (KT) coastal area, the Penghu (PH) open inner bay, and the Dongsha (DS) Atoll lagoon. Actual measurements of the substrate depth beneath the sediment and ground-penetrating radar (GPR) scans of the beach reveal that the coral reef bedrock in KT slopes landward. A field survey of the seagrass area in KT was conducted, and three cross-sectional profiles were analyzed to determine their topography, yielding a median sediment thickness of 88.2cm. Based on these measurements, the sediment volume was …

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Calculation Of Aquifer Transmissivity From Borehole Resistance Measurements And Pumping Test Results, Fen-Rong Yang, Chien-Wei Huang, Tien-Kuen Huang Jan 2025

Calculation Of Aquifer Transmissivity From Borehole Resistance Measurements And Pumping Test Results, Fen-Rong Yang, Chien-Wei Huang, Tien-Kuen Huang

Journal of Marine Science and Technology–Taiwan

Transmissivity is a crucial hydrogeological parameter for evaluating groundwater resources. This parameter is conventionally evaluated using pumping tests; however, these tests are costly and can be conducted at few sites. Many researchers have used ground resistance and pumping test data to estimate various hydrogeological parameters. In this study, borehole resistance survey and pumping test data collected by the Taiwan Groundwater Monitoring Network were used to establish the relationship between transmissivity and formation factor for aquifers in the Zhuoshui River alluvial fan. This relationship was then used to estimate the water output of the aforementioned aquifers in a cost-effective manner from …

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A Neural Network-Based Sliding Mode Adaptive Control System For Unmanned Surface Vehicles, Sun Qiaomei, An Liang, Jiang Linglin Jan 2025

A Neural Network-Based Sliding Mode Adaptive Control System For Unmanned Surface Vehicles, Sun Qiaomei, An Liang, Jiang Linglin

Journal of Marine Science and Technology–Taiwan

Over the past decades, numerous studies have explored the use of autonomous unmanned surface vehicles (USVs). Successful USV operation requires a robust tracking control system to perform a range of tasks. However, USV dynamics are uncertain, time-varying, and nonlinear. This paper presents a neural network-based sliding mode adaptive control (NNSMAC) system to enhance USV tracking performance. Trajectories were generated using spline and polynomial interpolation based on a set of N predefined waypoints. Simulation results show that the proposed method outperforms traditional sliding mode control in error reduction, enabling more effective tracking.

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The First Iucn Red List Of Cold-Water Corals Highlights Global Declines, Julia D. Sigwart, A. Louise Allcock, Renata Carolina Mikosz Arantes, Kelsey Archer Barnhill, Narissa Bax, Julia S. Beneti, Saskia Brix, Gudmundur Gudmundsson, Catherine S. Mcfadden, Severin A. Korfhage, Christi Linardich, Declan Morrissey, Pedro De Oliveira Nascimento, Bárbara De Moura Neves, Steinunn H. Ólafsdóttir, Stefán Ragnarsson, Kaveh Samimi-Namin, Íris Sampaio, Mark E. De Wilt Jan 2025

The First Iucn Red List Of Cold-Water Corals Highlights Global Declines, Julia D. Sigwart, A. Louise Allcock, Renata Carolina Mikosz Arantes, Kelsey Archer Barnhill, Narissa Bax, Julia S. Beneti, Saskia Brix, Gudmundur Gudmundsson, Catherine S. Mcfadden, Severin A. Korfhage, Christi Linardich, Declan Morrissey, Pedro De Oliveira Nascimento, Bárbara De Moura Neves, Steinunn H. Ólafsdóttir, Stefán Ragnarsson, Kaveh Samimi-Namin, Íris Sampaio, Mark E. De Wilt

Biological Sciences Faculty Publications

The most well-known species-based conservation tool is the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species. The current coverage of species in the Red List is known to under-represent benthic marine species. Cold-water corals (CWCs) are increasingly recognised as key to deep-water biodiversity and integral to protected vulnerable marine ecosystems (VMEs), but no deep-sea coral species were previously included in the Red List. We selected 22 cold-water coral species in the Northeast Atlantic, including 4 reef-forming stony corals and 18 octocorals including sea pens and gorgonians, and completed the first IUCN Red List global assessments …

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Thermal Tolerance Limits Of Mesophotic Corals In American Samoa, Daniel Barshis, Veronica Z. Radice, Katherine E. Parker, Nicholas Evensen Jan 2025

Thermal Tolerance Limits Of Mesophotic Corals In American Samoa, Daniel Barshis, Veronica Z. Radice, Katherine E. Parker, Nicholas Evensen

Biological Sciences Faculty Publications

We analyzed the thermal tolerances of multiple coral species from an upper mesophotic (38–40m) and a shallow reef (5–10m) with our portable Coral Bleaching Automated Stress System (CBASS). Depth generalist Montipora grisea (deep and shallow) and depth specialists Pachyseris speciosa and Leptoseris sp. (deep only) were assayed from Leone, located on the western coast of Tutuila in American Samoa. Fragments from 10 genotypes of each species were exposed to a 17-hour thermal stress assay reaching four maximum temperatures ranging from 30–38°C under in situ light conditions (150 μmol photons m−² s−¹ under a Lee Filters “deep …

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Form And Function In Mobulids: A Comparative Analysis Of Filter Morphology With Bioinspiration Applications, J. B. Teeple, S. R. Kahane-Rapport, K. E. Cohen, L. Hamann, J. A. Strother, E. W. M. Paig-Tran Jan 2025

Form And Function In Mobulids: A Comparative Analysis Of Filter Morphology With Bioinspiration Applications, J. B. Teeple, S. R. Kahane-Rapport, K. E. Cohen, L. Hamann, J. A. Strother, E. W. M. Paig-Tran

Biological Sciences Faculty Publications

Mobulas (manta and devil rays) are large-scale ram filter feeders that separate planktonic food particles from large volumes of water with minimal clogging. This contrasts with most human-made filters that can suffer from problematic clogging requiring additional mechanisms for clearing blocked surfaces and maintaining performance. Prior studies have shown that mobulas employ a unique mechanism referred to as ricochet separation to filter feed, whereby captive vortices in filter pores cause particles to bounce off the filter surfaces and away from the filter pores. This mechanism enables the filtration of particles smaller than the pore size and reduced clogging. However, few …

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Using Environmental Dna Metabarcoding To Investigate Diversity And Seasonal Variation Of Fishes In Humboldt Bay, California, Johnathon M. Richardson Jan 2025

Using Environmental Dna Metabarcoding To Investigate Diversity And Seasonal Variation Of Fishes In Humboldt Bay, California, Johnathon M. Richardson

Cal Poly Humboldt theses and projects

This study applied environmental DNA (eDNA) metabarcoding to characterize fish diversity and temporal patterns in fish assemblage structure within Humboldt Bay, California. This work advances ecological understanding of Humboldt Bay’s ichthyofauna, regional natural history and ecosystem function. Over one year (February 2023–January 2024), triplicate surface-water samples were collected every two weeks from a fixed site in Humboldt Bay (n = 78). DNA was extracted from filters and amplified using MiFish 12S primers in six replicate PCRs per sample. Amplicon concentrations were normalized, pooled and sequenced on an Illumina MiSeq platform (2×150 bp). Sequences were processed using a custom bioinformatics pipeline, …

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An Economic And Production Analysis Of Seaweed Farms In California And The Pacific Northwest, Brian Donovan Jan 2025

An Economic And Production Analysis Of Seaweed Farms In California And The Pacific Northwest, Brian Donovan

Cal Poly Humboldt theses and projects

Since the early 2010s, the seaweed aquaculture industry has steadily expanded in the United States, with states like Alaska, Maine, Hawaii, and Connecticut leading the way in the development of this emerging sector. However, information gaps remain concerning certain aspects of the domestic seaweed aquaculture industry. The purpose of this study was to examine the status of the seaweed aquaculture industry along the West Coast of the United States; specifically in the states of California, Oregon, and Washington. Seaweed farmers in these states were invited to voluntarily complete surveys asking important production, economic, and commercial questions regarding their operations. Data …

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Cultivation Of Winged Kelp (Alaria Marginata) In Humboldt Bay, Evan C. Simpson Jan 2025

Cultivation Of Winged Kelp (Alaria Marginata) In Humboldt Bay, Evan C. Simpson

Cal Poly Humboldt theses and projects

The cultivation potential of the winged kelp (Alaria marginata) was evaluated in Humboldt Bay, California, to further develop sustainable aquaculture in the region. Seasonality, depth, and system design were evaluated in regard to harvest biomass and quality. Results suggested that single-longline configurations at shallow depths (< 2 m) produced greater total biomass than a multi-longline system, suggesting enhanced water flow and reduced self-shading improved growth. Kelp grew best with a winter outplanting period (December-April), most likely due to environmental conditions (e.g., temperature, nutrients, and salinity) being within the kelp’s tolerable range, with as much as 2.24 kg/meter of kelp being harvested. These findings demonstrate that while the estuarine system has more variable conditions than predicted, A. marginata can be successfully cultivated in Humboldt Bay and highlight its potential as a viable crop for northern California’s emerging seaweed industry. Future work targeting the optimization of single-longline design and deployment timing may further improve yield and support regional goals for sustainable aquaculture and food security.

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A Porpoise-Driven Approach: Using Agent-Based Models To Predict Population Consequences Of Offshore Wind Noises On Gulf Of Maine Harbor Porpoises, Ben Greenberg Pridonoff Jan 2025

A Porpoise-Driven Approach: Using Agent-Based Models To Predict Population Consequences Of Offshore Wind Noises On Gulf Of Maine Harbor Porpoises, Ben Greenberg Pridonoff

Cal Poly Humboldt theses and projects

Marine mammals are increasingly exposed to anthropogenic noises, including from offshore wind activities, necessitating the development and refinement of tools to predict the effects of noise on their populations. Agent-based models (ABMs) are an effective tool that can simulate realistic movements and behaviors of animals to quantify population consequences of disturbance. In this study, I used the Europe-based ABM ‘DEPONS’ to (1) evaluate its effectiveness in a new environment, the Gulf of Maine, USA/Bay of Fundy, Canada, and (2) develop estimates of the population dynamics of local harbor porpoises (Phocoena phocoena) interacting with expected noises from proposed floating …

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No Detected Signal Of The 2022 Epizootic From Multiannual Diadema Antillarum Settlement Data In The Florida Keys, Jason Albrecht Jan 2025

No Detected Signal Of The 2022 Epizootic From Multiannual Diadema Antillarum Settlement Data In The Florida Keys, Jason Albrecht

Theses, Dissertations and Culminating Projects

The sea urchin Diadema antillarum is a key coral reef grazer that remains functionally extinct on many Caribbean reefs following a mass mortality event in 1983–84. In 2022, another widespread mortality event, likely caused by a scuticociliate parasite, again decimated D. antillarum at reefs across the Caribbean. Understanding the population-level impacts of this recent epizootic will be important for coral reef conservation efforts. This study examines multi-year larval settlement data from the Florida Keys to determine if the 2022 mortality event reduced larval settlement. Larval settlement was assessed monthly at three long-term monitoring sites (Delta Shoal, Tennessee Reef, and Pickles …

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Evaluating Annual Precipitation Extremes In The Us Great Plains Using Prism Data, Sumiaya Amin Preota, Gaurav Talukdar, Sam Zipper Jan 2025

Evaluating Annual Precipitation Extremes In The Us Great Plains Using Prism Data, Sumiaya Amin Preota, Gaurav Talukdar, Sam Zipper

School of Earth, Environmental, & Marine Sciences Faculty Publications

Understanding hydroclimatic extremes in the U.S. Great Plains (USGP) is crucial for effective water resource management, resiliency of agricultural systems, and mitigation of climate change impacts. This study examines changing hydroclimatic conditions in the USGP, with a focus on annual-resolution precipitation trends and extremes over the past 119 years (1904–2022) using precipitation data from the gridded PRISM climate dataset. We categorized annual-scale precipitation totals into six categories of hydroclimatic extremes: (1) isolated wet extremes, (2) isolated dry extremes, (3) dry-to-dry recurring extremes, (4) wet-to-wet recurring extremes, (5) dry-to-wet whiplash extremes, and (6) wet-to-dry whiplash extremes. “Recurring” and “whiplash” are both …

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Nesting Population Trend Of The Leatherback Sea Turtle In Bocas Del Toro Province And Comarca Ngäbe-Buglé, Panama For The Period 2002–2022, Sonia Gutiérrez Parejo, Susan E. Piacenza, Raúl García, Cristina Ordóñez, Roldán A. Valverde Jan 2025

Nesting Population Trend Of The Leatherback Sea Turtle In Bocas Del Toro Province And Comarca Ngäbe-Buglé, Panama For The Period 2002–2022, Sonia Gutiérrez Parejo, Susan E. Piacenza, Raúl García, Cristina Ordóñez, Roldán A. Valverde

School of Earth, Environmental, & Marine Sciences Faculty Publications

Sea turtle biologists have made sustained efforts to understand the global status of leatherback sea turtle populations. However, despite progress in assessments, demographics, and ecology, key uncertainties persist in tracking leatherback population trends. Trend analyses have historically focused on nesting beaches, with nest counts providing a widely used index for population abundance. Here, we analysed 20 years of annual nest abundance at four main nesting beaches (Soropta, Bluff, Playa Larga and Chiriquí) in Bocas del Toro province and the Comarca Ngäbe-Buglé, Panama, which constitute the largest nesting leatherback sea turtle population in Central America. We conducted daily nest counts during …

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Dataset On Indoor And Outdoor Pm2.5 Concentrations At Two Residences Using Low-Cost Sensors In The Rio Grande Valley Region Of South Texas, Kabir Bahadur Shah, Sai Deepak Pinakana, Mkhitar A. Hobosyan, Armando Montes, Amit U. Raysoni Jan 2025

Dataset On Indoor And Outdoor Pm2.5 Concentrations At Two Residences Using Low-Cost Sensors In The Rio Grande Valley Region Of South Texas, Kabir Bahadur Shah, Sai Deepak Pinakana, Mkhitar A. Hobosyan, Armando Montes, Amit U. Raysoni

School of Earth, Environmental, & Marine Sciences Faculty Publications

Fine particulate matter (PM2.5) is one of the criteria air pollutants associated with adverse respiratory and cardiovascular health effects. This dataset contains hourly and daily averaged measurements of PM2.5 concentrations (µg/m3) collected from two residential homes in the Rio Grande Valley (RGV) Region of South Texas, using PurpleAir-II-SD low-cost sensor. In addition, the dataset also includes temperature (ºC) and relative humidity (%) measured by the sensors. The data was collected for one month during the summer season from indoor (kitchen) and outdoor (front yard) environments at two locations: Home-1 in Weslaco City from June 16, 2024, to July 16, 2024, …

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Foreign Object Detection System Development Using Edge Devices Integrated With Quadcopter Autonomous Tracking, Chi-Chia Huang, Ching-Hung Lee Jan 2025

Foreign Object Detection System Development Using Edge Devices Integrated With Quadcopter Autonomous Tracking, Chi-Chia Huang, Ching-Hung Lee

Journal of Marine Science and Technology–Taiwan

This study proposes an all-weather autonomous foreign-object detection system capable of operating in low-light environments. We used a highly mobile quadcopter equipped with an edge-computing device as the inspection platform. On the software side, we integrated a low-light image enhancement model, a path-tracking algorithm, and a foreign object detection model to achieve rapid object detection. A lightweight, low-light image-enhancement model reduces the need for additional lighting equipment, thereby enabling reliable detection under low-light conditions. The path-tracking algorithm integrates a lightweight semantic segmentation model with traditional image-processing techniques to establish flight paths efficiently and reliably. The foreign-object detection component employs state-of-the-art …

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Optimization Of Underactuated Ship Sliding Mode Controller Based On The Ddpg Algorithm, Lin Ma, Mingzhe Qi, Shicai Chen, Hongwei Bian, Jian Zhang Jan 2025

Optimization Of Underactuated Ship Sliding Mode Controller Based On The Ddpg Algorithm, Lin Ma, Mingzhe Qi, Shicai Chen, Hongwei Bian, Jian Zhang

Journal of Marine Science and Technology–Taiwan

Due to the development of ship intelligence, the demand for precise controllers is increasing day by day. In traditional design, the trial-and-error method often leads to the use of inaccurate controller parameters, causing oscillations when environmental disturbances are present. To address these issues, this study introduces deep learning to optimize the controller parameters, particularly those used for sliding mode controllers in underactuated ships. We adopt the Deep Deterministic Policy Gradient (DDPG) algorithm based on the Actor Critic framework. By freely setting the reward function to match the control objective, the trained model can output more accurate controller parameters, with the …

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Experiments On Aluminum Alloy Additive Layer Waam Lamination Using The Arc Current Reduction Technique, Jukkapun Greebmalai, Eakkachai Warinsiriruk, Chao-Hsiang Hsiao, Yin-Tien Wang Jan 2025

Experiments On Aluminum Alloy Additive Layer Waam Lamination Using The Arc Current Reduction Technique, Jukkapun Greebmalai, Eakkachai Warinsiriruk, Chao-Hsiang Hsiao, Yin-Tien Wang

Journal of Marine Science and Technology–Taiwan

Recent advancements in additive manufacturing have been propelled by innovations in processes, materials, and fabrication techniques. This study specifically focuses on the optimizing Wire and Arc Additive Manufacturing (WAAM) within the Gas Metal Arc Welding (GMAW) process. The goal is to build laminated layers using aluminum alloy from the five-thousand series. In this research, a novel technique is introduced that employs a reduced arc-current during the additive layer progress for aluminum alloys, along with a double pulse current in the GMAW process to enhance weldability. The material used for addition is ER5356 aluminum wire, which is applied to an Al-5083 …

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An Optimization Model For Supporting Bunkering Decisions In Bulk Shipping, Chung-Cheng Lu, Hui-Chieh Li, Hung-Yu Chen Jan 2025

An Optimization Model For Supporting Bunkering Decisions In Bulk Shipping, Chung-Cheng Lu, Hui-Chieh Li, Hung-Yu Chen

Journal of Marine Science and Technology–Taiwan

This study addresses a bunkering optimization problem for bulk shipping carriers that explores route deviation to find optimal bunkering locations and amounts. A mixed integer linear programming (MILP) model is developed to determine optimal bunkering decisions that minimize total operating costs, including total daily operating costs, bunkering costs, port charges and surcharges, while observing time window constraints at loading/unloading ports. The proposed model is evaluated using instances generated from real data provided by H company with its operational headquarters in Taipei, Taiwan, which operates a fleet of handysize ships in East and South Asia. The results indicate that optimization models …

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Assessment Of Coastal Navigation Safety: A Case Study Of Boka Bay With Stakeholder Perspectives, Ivan Mraković, Rino Bošnjak Jan 2025

Assessment Of Coastal Navigation Safety: A Case Study Of Boka Bay With Stakeholder Perspectives, Ivan Mraković, Rino Bošnjak

Journal of Marine Science and Technology–Taiwan

The navigational safety of Boka Bay, i.e., a critical maritime area along the Adriatic coast, is of great importance owing to its ecological sensitivity, diverse marine traffic, and significant economic activity. This study provides a comprehensive assessment by analyzing the perspectives of various stakeholders, including seafarers, local pilots, skippers, regulatory authorities, and others engaged in maritime activities within the bay. Using a structured questionnaire survey, both quantitative and qualitative data were collected in formats such as descriptive responses, Yes/No choices, and Likert scale ratings, ensuring a well-rounded understanding of navigational practices and challenges. The data were analyzed using descriptive statistics, …

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A Hybrid Model To Assess Commercial Port Resilience In Taiwan, Po-Hsing Tseng, James J.H. Liou Jan 2025

A Hybrid Model To Assess Commercial Port Resilience In Taiwan, Po-Hsing Tseng, James J.H. Liou

Journal of Marine Science and Technology–Taiwan

Since 2021, international commercial ports have faced unprecedented challenges (e.g., COVID-19 pandemic, Suez Canal congestion), impacting daily life, work, human well-being, properties, the environment, and socio-economic activities. The adaptation capability resilience of international commercial ports to respond to external changes has become crucial. This study develops an expert knowledge-based hybrid multi-criteria decision-making model integrating Best-Worst Method (BWM), Rough Dombi Aggregator, and Combined Compromise Solution (CoCoSo) to evaluate port resilience capabilities, using Taiwan's international commercial ports as a case study. We propose four evaluation dimensions encompassing 13 indicators: detection capability, resistance capability, resource integration capability, and recovery capability. The BWM determined …

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An Evaluation Of The Possibility And Effectiveness Of Renewable Energy In Container Terminal At Jinhae New Port, Min-Seop Sim, Yul-Seong Kim, Chang-Hee Lee Jan 2025

An Evaluation Of The Possibility And Effectiveness Of Renewable Energy In Container Terminal At Jinhae New Port, Min-Seop Sim, Yul-Seong Kim, Chang-Hee Lee

Journal of Marine Science and Technology–Taiwan

The international goals of combating climate change and reducing greenhouse gas emissions are driving container terminal operators to adopt renewable energy solutions. This study evaluated the feasibility and effectiveness of introducing renewable energy and eco-fuels for energy independence at the Jinhae New Port Container Terminal, South Korea. Using portfolio analysis, eight renewable energy technologies (solar power, solar thermal energy, wind energy, hydropower, marine energy, geothermal energy, bioenergy, and waste-to-energy) and seven eco-friendly fuels (electricity, liquefied natural gas, liquefied petroleum gas, hydrogen fuel cells, ammonia fuel cells, bioenergy, and hybrid systems) were assessed. Survey data from stakeholders identified solar, wind, and …

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Accelerated Aging System For Pinniped Tags, Sean Shermer, Nathan Vasquez, Deekshitha Garige Jan 2025

Accelerated Aging System For Pinniped Tags, Sean Shermer, Nathan Vasquez, Deekshitha Garige

Undergraduate Scholarship

This project focused on the design of an accelerated aging system intended to evaluate the durability of pinniped identification tags used in marine mammal research. The system was developed in collaboration with the Cal Poly Humboldt Marine Lab and NOAA, under the guidance of Dr. Dawn Goley, to address the limitations of field based durability testing, which is slow, inconsistent, and difficult to reproduce. The primary objective was to create a repeatable laboratory testing framework capable of simulating multiple environmental stressors experienced by pinniped tags. This includes the accelerated tests of UV radiation, mechanical abrasion, temperature cycling and biological fouling. …

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The Macroalgal Composition Differs Among Depths And Zones In Cuban Mesophotic Coral Reef Eosystems, Beatriz Martínez-Daranas, Dennis Hanisak, Partricia M. González-Sánchez, Stephanie Farrington, John K. Reed Jan 2025

The Macroalgal Composition Differs Among Depths And Zones In Cuban Mesophotic Coral Reef Eosystems, Beatriz Martínez-Daranas, Dennis Hanisak, Partricia M. González-Sánchez, Stephanie Farrington, John K. Reed

Gulf and Caribbean Research

Previously the algal community of Cuban mesophotic coral reef ecosystems (MCEs) has not been characterized quantitatively. The objective of this study was to explore the distribution of macroalgae around Cuba and their depth profiles within the mesophotic zone (30−150 m). Data on the algal community were obtained in 2017 during 43 ROV (remotely operated vehicle) dives around Cuba’s shelf. Scientists specializing in algal taxonomy watched the live ROV video on board the ship and recorded algal presence every ~5—10 min in a database. Algae were identified to the lowest possible taxa, and algal presence/absence was analyzed in 20 m depth …

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Presence Of Potential Nursery Habitat For The Lemon Shark In Mississippi Coastal Waters, Lindsay K. Bomgardner, P. O. Grammer, Angie Hoover, Anna Millender, Jeremy Higgs, Jill M. Hendon, Michael J. Andres Jan 2025

Presence Of Potential Nursery Habitat For The Lemon Shark In Mississippi Coastal Waters, Lindsay K. Bomgardner, P. O. Grammer, Angie Hoover, Anna Millender, Jeremy Higgs, Jill M. Hendon, Michael J. Andres

Gulf and Caribbean Research

No abstract provided.

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Ina Scuba: Mobilization Of French West Indies Scuba Diving Clubs To Rapidly Improve Knowledge On Threatened Marine Species. Case Of The White-Spotted Eagle Ray (Aetobatus Narinari)., Océane Beaufort, Rocio Prieto González Jan 2025

Ina Scuba: Mobilization Of French West Indies Scuba Diving Clubs To Rapidly Improve Knowledge On Threatened Marine Species. Case Of The White-Spotted Eagle Ray (Aetobatus Narinari)., Océane Beaufort, Rocio Prieto González

Gulf and Caribbean Research

The White—Spotted Eagle Ray (Aetobatus narinari), listed as Endangered on the IUCN Red List since 2021, is experiencing alarming population declines, underscoring the urgent need for targeted conservation efforts. This species, which plays a vital ecological role in marine food webs, has biological and ecological characteristics that make it particularly vulnerable to habitat degradation and anthropogenic pressures, particularly fishing, tourism, and maritime traffic. In the French West Indies (FWI), the paucity of data on the White—Spotted Eagle Ray remains a major obstacle to the development of effective, island—specific conservation strategies. To address this gap, the INA Scuba participatory …

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