Optimum Design Of The Underwater Discharge System Based On Surrogate Modeling,
2021
Department of Naval Architecture and Ocean Engineering, Seoul National University, Seoul, Republic of Korea
Optimum Design Of The Underwater Discharge System Based On Surrogate Modeling, Jisang Ha, Myung-Il Roh, Seung-Ho Ham, Sung-Jun Lee
Journal of Marine Science and Technology–Taiwan
Underwater vehicles are equipped with a device for discharging projectiles, called the underwater discharge system. Because these vehicles have limited space, many studies have attempted to reduce the volume of the underwater discharge system while improving its performance. However, owing to the characteristics of the system, the occupied volume and performance conflict with each other. Therefore, minimizing the occupied volume while satisfying the required performance criteria is the most significant requirement in the design stage. To address this, an optimization problem for the underwater discharge system was mathematically formulated and solved using multi-objective genetic algorithms. Additionally, we proposed a method …
An Analysis Of Key Influencing Factors On Island Tourism Revisit Intentions – Evidence From The Matsu Islands,
2021
Dept. of Shipping and Transportation Management, National Taiwan Ocean University, Taiwan
An Analysis Of Key Influencing Factors On Island Tourism Revisit Intentions – Evidence From The Matsu Islands, Chun-Chieh Wang, Hsiao-Chuan Liu, Hsuan-Shih Lee, Cheng-Chi Chung
Journal of Marine Science and Technology–Taiwan
Sightseeing and tourism not only brings economic benefits to the local community but also drive the development of related industries. In 1992, when the Matsu’s battlefield mission was dissolved, tourism became one of the key development strategies to boom the region. Although the number of visitors to Matsu Islands has risen significantly in recent years, how to increase the island’s willingness to revisit the island has been an important issue. Since local tourism has its own characteristics, island tourism marketing strategies should be different. Many previous studies have quantified the relationship between tourism area satisfaction and willingness to revisit, but …
3d Numerical Simulation Of Kuroshio-Induced Wake Near Green Island, Taiwan,
2021
epartment of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
3d Numerical Simulation Of Kuroshio-Induced Wake Near Green Island, Taiwan, Tien-Hung Hou, Jen-Yi Chang, Chia-Cheng Tsai, Tai-Wen Hsu
Journal of Marine Science and Technology–Taiwan
In this research, Kuroshio-induced vortex shedding in the lee of Green Island was numerically studied using the three-dimensional Princeton Ocean Model. The temporal and spatial characteristics of the vortex street were analyzed at different tidal levels, wind fields and water depths. The nu-merical results were validated by comparing with in-situ measurements from the Green Island tidal station, shipboard acoustic doppler current profiler (ADCP), conductivi-ty-temperature-depth (CTD) profiler, and moderate resolution imaging spectroradiometer (MODIS) satellite image datasets. Also, the three-dimensional results of velocity, temperature, and salinity fields were compared well with observational data. Furthermore, the influence depths of the wind effect and …
Intelligent Fuzzy Control With State-Derivative Feedback For Takagi-Sugeno Fuzzy Stochastic Singular Systems,
2021
Department of Marine Engineering, National Taiwan Ocean University, Keelung, Taiwan, R. O. C.
Intelligent Fuzzy Control With State-Derivative Feedback For Takagi-Sugeno Fuzzy Stochastic Singular Systems, Wen-Jer Chang, Kuang-Yow Lian, Cheung-Chieh Ku, Che-Lun Su
Journal of Marine Science and Technology–Taiwan
This document deals with the problem of passive fuzzy controller design with the state-derivative feedback approach for the nonlinear stochastic singular systems. Recently, the singular systems have a greater focus on literature because they can keep more physical system characteristics than conventional systems. At first, the Takagi-Sugeno fuzzy stochastic singular models are used to represent the nonlinear stochastic singular systems. Then, the state-derivative feedback approach and parallel distributed compensation method are employed to design the passive fuzzy controllers. In the design process, the Lyapunov stability conditions are developed subject to multiple performance constraints, including the passivity constraint and decay rate …
Sea Ice Warning Visualization And Path Planning For Ice Navigation Based On Radar Image Recognition,
2021
Merchant Marine College, Shanghai Maritime University, Shanghai, China
Sea Ice Warning Visualization And Path Planning For Ice Navigation Based On Radar Image Recognition, Tsung-Hsuan Hsieh, Shengzheng Wang, Huijia Gong, Wei Liu, Ning Xu
Journal of Marine Science and Technology–Taiwan
Ice navigation is currently one of the important issues in path planning studies. Most studies are using sea ice models or ice charts for large-scale path planning, but the weather and ice conditions in the polar waters usually change quickly and are not easy to predict. Under these conditions, small-scale path planning that can be adjusted in time for sea ice collision avoidance is needed. This study uses marine radar imaging to reconstruct the ice navigation scene, and establishes a visual-ization function of sea ice warning on the radar image. We combine the bidirectional rapidly-exploring random tree (B-RRT) algorithm and …
Enhancing Marine Administrative Management Based On Human Factor Through Safety Criteria,
2021
Department of Business Administration, National Taipei University of Business
Enhancing Marine Administrative Management Based On Human Factor Through Safety Criteria, Wen-Cheng Lin, Hsin-Hung Cheng
Journal of Marine Science and Technology–Taiwan
This study aims to improve maritime safety by enhancing administrative management based on human factors. This study used Fuzzy analytic hierarchy process to analyze the risks and threats regarding safety maritime criteria. Establishing administrative reform is given the highest priority. First, the current model for crew training system is explored. Second, the marine surveyor is examined to determine if it is professional enough for inspection work. Third, the investigation system used by maritime safety investigators should be inspected. The suggestions mentioned expect to establish a maritime administrative reform that could pave the way for the application of maritime safety around …
Experimental Study On Treatment Of Ballast Water By Inert Flue Gas Deoxidation,
2021
School of Energy and Power, Jiangsu University of Science and Technology, Zhenjiang, China
Experimental Study On Treatment Of Ballast Water By Inert Flue Gas Deoxidation, Guozhi Bao, Peng Yang, Rui Da, Junxia Li, Guanghui Zhao, Ning Chen
Journal of Marine Science and Technology–Taiwan
In this paper, the antimicrobial effect of inert flue gas on indicator microorganisms in ballast water was investigated based on a 265h test. The inert flue gas consists of nitrogen (N2) and carbon dioxide (CO2) the microorganisms include Chlorella and Escherichia coli. Within the scope of the test, the killing effect of the microbes treated by combining N2 and CO2 was higher than that of using only either N2 or CO2. When the dissolved oxygen concentration in the ballast water was 0.5 mg/L and the pH value was 6, the killing effect was the highest. At this time, the mortality …
Temperature Stress And Disease Drives The Extirpation Of The Threatened Pillar Coral, Dendrogyra Cylindrus, In Southeast Florida,
2021
Nova Southeastern University
Temperature Stress And Disease Drives The Extirpation Of The Threatened Pillar Coral, Dendrogyra Cylindrus, In Southeast Florida, Nicholas P. Jones, Lystina Kabay, Kathleen Semon Lunz, David S. Gilliam
Marine & Environmental Sciences Faculty Articles
Rare species population dynamics can elucidate the resilience of an ecosystem. On coral reefs, climate change and local anthropogenic stressors are threatening stony coral persistence, increasing the need to assess vulnerable species locally. Here, we monitored the threatened pillar coral, Dendrogyra cylindrus, population in southeast Florida, USA, in relation to consecutive heat stress events in 2014 and 2015. In the fall of each year, D. cylindrus colonies bleached following intense thermal stress and by June 2020 all monitored colonies died from a white-syndrome type disease. This resulted in the ecological extinction of D. cylindrus in the Southeast Florida Coral …
Fisheries Food Webs: Quantifying Habitat-Use, Trophic Structure, And Energetic Pathways In Coastal Tanzania,
2021
Louisiana State University
Fisheries Food Webs: Quantifying Habitat-Use, Trophic Structure, And Energetic Pathways In Coastal Tanzania, Mario Fernando Hernandez
LSU Doctoral Dissertations
Commercial and recreational fisheries are a valuable resource to millions of people around the world. Developing countries are particularly dependent on the revenue provided by locally harvested fish with total exports from these nations valued at $80 billion USD. For Tanzania, fisheries provide not only a source of revenue but an important source of protein with an estimated 25 to 30kg of fish consumed per person every year. There is no doubt that high fisheries production is critical to the well-being of millions of livelihoods along the Tanzanian coast. An important but poorly understood driver of fisheries production is the …
Effects Of Salinity On Eastern Oysters: Locating Lower-Salinity Tolerant Populations And Defining Resource Zones Suitable To Restoration, Fisheries, And Aquaculture.,
2021
Louisiana State University and Agricultural and Mechanical College
Effects Of Salinity On Eastern Oysters: Locating Lower-Salinity Tolerant Populations And Defining Resource Zones Suitable To Restoration, Fisheries, And Aquaculture., Lauren Swam
LSU Master's Theses
Eastern oysters (Crassostrea virginica) provide valuable ecosystem services and support a productive commercial industry in the northern Gulf of Mexico. Declining abundance from water quality changes and other factors drives development of management and restoration strategies focused on a comprehensive, metapopulation approach. Identifying oyster resource zones based on water quality combined with selective breeding of oysters adapted to specific conditions provides strategies to support aquaculture development and ensure resilient oyster populations and high production. Using 2015-2019 satellite-derived continuous salinity and temperature data for coastal Louisiana, this work created maps defining oyster resource zones supportive of (1) broodstock sanctuary …
Caribbean Yellowtail Snapper Ocyurus Chrysurus: Filling In Critical Gaps In Research For Life History And Novel Ageing Validation Utilizing Δ14C,
2021
University of South Carolina
Caribbean Yellowtail Snapper Ocyurus Chrysurus: Filling In Critical Gaps In Research For Life History And Novel Ageing Validation Utilizing Δ14C, Sarah Zajovits
Theses and Dissertations
Yellowtail snapper Ocyurus chrysurus is an important fisheries species in the US Caribbean; in waters of Puerto Rico, it ranks second for reef fishes in terms of annual total commercial landings. However, a paucity of information exists concerning basic life history information for Caribbean yellowtail snapper populations. This study provides the first comprehensive documentation of age, growth, and reproductive biology of yellowtail snapper from the Caribbean and is the first to directly validate age estimation in this species. Sampling of 1731 yellowtail snapper occurred in Puerto Rico and the U.S. Virgin Islands during 2013-2021 from fisheries-dependent and –independent efforts. Fish …
Synergy Between Behavioural Research On Beluga Whales (Delphinapterus Leucas) Conducted In Zoological And Wild Settings,
2021
St. Mary’s University
Synergy Between Behavioural Research On Beluga Whales (Delphinapterus Leucas) Conducted In Zoological And Wild Settings, Heather Manitzas Hill, Deirdre Yeater, Michael Noonan
Psychology Faculty Publications
Behavioural observations of captive beluga whales have complemented and extended much of what has been learnt about this species in the wild. Aquarium-based research has provided finer-scale specificity for many topics, including the seasonal breeding pattern that is characteristic of this species, as well as socio-sexual behaviour that appears to be an important part of the behavioural repertoire of this species. One example is a strong propensity for male–male social interactions that begin to develop at an early age. In addition, detailed behavioural milestones in calves have been documented in ways that extend that which have been collected from wild …
Investigating Larval Spillover From Oyster Aquaculture Through Geospatial Habitat Suitability Index Modeling: A Damariscotta River Estuary Case Study,
2021
University of New England
Investigating Larval Spillover From Oyster Aquaculture Through Geospatial Habitat Suitability Index Modeling: A Damariscotta River Estuary Case Study, Daniel F. Delago
All Theses And Dissertations
The eastern oyster (Crassostrea virginica) supports the ecological function of estuarine ecosystems by creating biogenic reef habitat (Purchon, 2013), and positively influencing coastal biogeochemistry in intertidal, and subtidal environments (Humphries et al., 2016; Ray and Fulweiler, 2020). As anthropogenic impacts continue to influence the health of marine environments globally (Halpern et al., 2008), oyster reef restoration is gaining increased attention as a means of maintaining the function of estuarine systems (Beck et al, 2011). Shellfish aquaculture has gained increased attention, contributing 21% of all aquaculture production globally (FAO 2020). Shellfish aquaculture provides a suite of social-ecological benefits while …
The Potential Of Indian River Lagoon Muck To Act As A Reservoir For Emerging Organic Contaminants,
2021
Florida Institute of Technology
The Potential Of Indian River Lagoon Muck To Act As A Reservoir For Emerging Organic Contaminants, Gregory David Belson
Theses and Dissertations
Pharmaceuticals, pesticides, and personal care products are frequently found in sediments and waterways around the world. These chemicals, collectively known as Emerging Organic Contaminants (EOCs) can harm the environments in which they are deposited by killing or stressing the local flora and fauna. These EOCs also can be released back into the water column when these substrates are disturbed. Such sediments and their associated EOCs are particularly problematic in urbanized areas. However, the particular composition of urbanization-associated sediments as well as their potential to harbor EOCs needs to be evaluated in the context of their environment, to ensure proper mitigation …
Adding Value Through Sustainability: Incentivizing An Ecosystem Approach To Oyster Aquaculture In Maine,
2021
University of New England
Adding Value Through Sustainability: Incentivizing An Ecosystem Approach To Oyster Aquaculture In Maine, Samuel Feldman
All Theses And Dissertations
This study identified oyster farming practices that have the potential to increase the sustainability of Maine’s oyster industry while increasing its value. Practices aligned with the principles of the ecosystem approach to aquaculture were gleaned from semi-structured interviews and surveys of oyster farmers and their buyers. Themes from interview transcripts were developed using thematic analysis. Survey data was used to triangulate interview transcript data. As a result, sustainable oyster farming practices were identified that had direct and indirect connections to the value of Maine’s oysters. Practices with direct connections to increased oyster value included conducting and advertising actions of increased …
Dissolved Nitrogen Cycling In The Eastern Canadian Arctic Archipelago From Stable Isotopic Data,
2021
University of South Carolina
Dissolved Nitrogen Cycling In The Eastern Canadian Arctic Archipelago From Stable Isotopic Data, Holly Westbrook
Theses and Dissertations
Climate change is expected to drastically alter the input of inorganic nitrogen (N) sources in the Eastern Canadian Arctic Archipelago (ECAA) with increasing discharge from glacial meltwater and permafrost thawing. Since dissolved inorganic N is generally depleted in surface waters, dissolved organic N (DON) could represent a significant source of nutrients limiting primary production in Arctic ecosystems. Yet, few DON data for this region exist. We analyzed stable isotopes (δ15N and δ 18O of DON and NO3-) to investigate dissolved nitrogen cycling in glacial rivers and marine surface samples collected in the ECAA during summer …
Deep-Sea Biodiversity At The Extremes Of The Salas Y Gómez And Nazca Ridges With Implications For Conservation,
2021
The University of Texas Rio Grande Valley
Deep-Sea Biodiversity At The Extremes Of The Salas Y Gómez And Nazca Ridges With Implications For Conservation, Alan M. Friedlander, Whitney Goodell, Jonatha Giddens, Erin E. Easton, Daniel Wagner
School of Earth, Environmental, & Marine Sciences Faculty Publications
The Salas y Gómez and Nazca ridges are underwater mountain chains that stretch across 2,900 km in the southeastern Pacific and are recognized for their high biodiversity value and unique ecological characteristics. Explorations of deep-water ecosystems have been limited in this region, and elsewhere globally. To characterize community composition of mesophotic and deep-sea demersal fauna at seamounts in the region, we conducted expeditions to Rapa Nui (RN) and Salas y Gómez (SyG) islands in 2011 and Desventuradas Islands in 2013. Remote autonomous baited-cameras were used to conduct stationary video surveys between 150–1,850 m at RN/SyG (N = 20) and 75–2,363 …
Markedly Similar Growth And Longevity Of Green Jobfish Aprion Virescens Over An Expansive Geographic Range Between The Hawaiian Archipelago And The Eastern Indian Ocean,
2021
NOAA Fisheries, Hawaii
Markedly Similar Growth And Longevity Of Green Jobfish Aprion Virescens Over An Expansive Geographic Range Between The Hawaiian Archipelago And The Eastern Indian Ocean, Joseph M. O'Malley, Corey B. Wakefield, Michael J. Kinney, Stephen J. Newman
Fisheries Research Articles
The Green Jobfish Aprion virescens supports important commercial, recreational, and subsistence fisheries throughout its Indo-Pacific range. Concerns with previous estimates of age and growth from fish in Hawaii, along with evidence of variability in these parameters from locations outside the Pacific Ocean, limits their reliability as input parameters for assessments of this species, particularly in Hawaii. Previously validated aging criterion were applied to fish collected from within the Hawaiian Archipelago (main Hawaiian Islands and Northwestern Hawaiian Islands) and the eastern Indian Ocean to provide length-at-age, growth, and longevity information for stock assessment and management purposes as well as to further …
Splitting The Scatter: Distinguishing Marine Organisms From Oceanographic Structures Using Acoustic Monitoring,
2021
Fisheries Resources Institute, Japan Fisheries Research and Education Agency,Japan
Splitting The Scatter: Distinguishing Marine Organisms From Oceanographic Structures Using Acoustic Monitoring, Zhen Lu, Daisuke Hasegawa, Takahiro Tanaka, David M. Spencer, Yuji Okazaki, Takeshi Okunishi
Journal of Marine Science and Technology–Taiwan
In the northwest Pacific Ocean, off the Sanriku coast of Japan, convergence between the Tsugaru Warm Current (TWC) and the cold Oyashio Current (OC) results in the formation of highly dynamic oceanographic features that promote high biodiversity and generate hotspots for a range of commercially important fisheries. However, their effects on local biodiversity over much smaller spatiotemporal scales ( < 1 km) remains unclear. With the development of acoustic technology in recent years, echo-sounders are increasingly being used to conduct high-precision fishery resource assessments and detect small-scale variability in the oceanic thermohaline structure. In this study, we conducted a simultaneous hydrographic and dual-frequency echo-sounder survey to discriminate oceanographic features and marine organisms in the TWC-OC confluence zone. Echograms of acoustic backscatter measured at 38 kHz detected similar oceanographic features that were obtained from our hydrographic survey observations, but these features were less pronounced in the 120 kHz echograms. The dynamic oceanographic structure in the TWC-OC zone returned a large amount of backscatter, making it difficult to identify marine organisms from the scatter. The frequency differences of volume backscattering strength (SV) were, however, able to distinguish oceanographic structures from zooplankton detections. Outcomes from this study highlight the difficulty of distinguishing between hydrographic and biological detections in dynamic oceanographic environments. Further research into the acoustic frequency characteristics of heterogeneous hydrographic features will help better understand how species distributions are affected, so that the acoustic method can be used to provide more accurate estimates of species abundance.
Fine-Scale Vertical Movements And Behavior Of Immature Skipjack Tuna (Katsuwonus Pelamis) Off Eastern Taiwan,
2021
Eastern Marine Biology Research Center, Fisheries Research Institute, Taiwan
Fine-Scale Vertical Movements And Behavior Of Immature Skipjack Tuna (Katsuwonus Pelamis) Off Eastern Taiwan, Wei-Chuan Chiang, Takayuki Matsumoto, Shian-Jhong Lin, Qi-Xuan Chang, Michael K. Musyl, Yuan-Shing Ho, Fumio Ohta
Journal of Marine Science and Technology–Taiwan
Skipjack tuna are globally distributed in tropical and temperate seas but little is known about their fine-scale diving patterns and how fish size and (or) maturity influences patterns off eastern Taiwan. A total of 211 immature skipjack (36 e 47 FL cm) in the study were caught by trolling near subsurface fish aggregating devices (FADs) near Green Island (southeastern Taiwan) and were tagged with Lotek LAT-2910 archival tags. The low rate of recovery (2.4%) suggests a high post-release mortality but this low rate could also be consistent with large population sizes, dispersal, tag loss or uncooperative fishers. Five individuals were …
