Oceanography and Atmospheric Sciences and Meteorology Commons^™

Catch Rates And Distribution Pattern Of The Silky Shark, Carcharhinus Falciformis, Caught By The Taiwanese Large-Scale Longline Fishery In The Indian Ocean, Chia Yun Li, Xing-Han Wu, Shang Yin Vanson Liu, Sheng-Ping Wang, Wen-Pei Tsai

Journal of Marine Science and Technology–Taiwan

The silky shark, Carcharhinus falciformis, is widely distributed in tropical and temperate waters, and it is a common bycatch species for tuna longline fisheries. This study examined the distribution of and presents relative abundance indices of the silky shark in the Indian Ocean by using logbook and observer data from the Taiwanese large-scale tuna longline fishery between 2005 and 2019. Due to the high zero catch rate, a zero-inflated negative binomial (ZINB) model was used to standardize catch per unit effort. Due to a lack of detailed targeting information, the fishery strategy was identified by using cluster analysis based on …

Accumulation And Bioavailability Of Heavy Metals (Cadmium, Chromium, Nickel, Lead And Zinc) In Water And Sediment Samples In The Musa Creek, Northwest Coasts Of The Persian Gulf, Saghafiankhoo Sedigheh, Battaleb-Looie Sedigheh, Amanipoor Hakimeh, Dravishi Khatooni Javad, Ghanemi Kamal

Journal of Marine Science and Technology–Taiwan

The current study aimed to investigate the total concentrations of heavy metals in water and sediment samples as well as their bioavailability in sediments of Musa Creek. Twenty samples including 10 sediments and 10 water samples were collected from 10 stations. The concentration of heavy metals was measured using inductively coupled plasma–mass spectrometry. The bioavailability of heavy metals was carried out by first step of Tessier sequential extraction method so called single extraction in the manuscript. The results showed that the mean concentrations of cadmium, chromium, nickel, and zinc in water samples was 0.17, 7.44, 43.80, and 8.85 µg/L, respectively. …

Parametric Analyses Of The Dynamic Response And Fatigue Life Of A Compliant Vertical Access Riser With Internal Flow, Fuheng Li, Haiyan Guo, Xiaomin Li, Zhen Liu, Honglu Gu, Peng Cui

Journal of Marine Science and Technology–Taiwan

Subsea interventions on wellheads can be directly performed from a platform using a compliant vertical access riser (CVAR), thereby incurring tremendous economic benefits. The dynamic response and the fatigue damage of a CVAR subjected to regular waves are important for assessing its application feasibility. Therefore, a reasonable numerical model is presented for assessing the damage to a CVAR considering the internal flow using the slender rod theory. The finite element method combined with a Newmark-β scheme is employed to discretize the equations and update the time integration. The Palmgren-Miner rule is applied for fatigue life prediction, focusing on the wave-induced …

Using The Inverse Method To Investigate Flow Models For Mixed Convection Of Annular Finned Tube Heat Exchanger, Han-Taw Chen, Cheng-Hui You, Wei-Lun Hsu, Jiang-Ren Chang

Journal of Marine Science and Technology–Taiwan

The inverse heat conduction method (IHCM) and three-dimensional (3D) computational fluid dynamic (CFD) in combination with are used to select the appropriate flow model and near-wall treatment for the mixed convection of the annular finned tube heat exchanger. Thus, the numerical results obtained by all k-ε models and near-wall treatments are yielded for 4 m/s ≤ Va ≤ 5 m/s. First, IHCM combined with is applied to estimate and Q values. The obtained estimates of and Q are used as reference values for CFD. The results show that the Tk and results obtained by the standard (STD) k-ε model with …

Prediction Of Remaining Useful Life Of Wind Turbine Shaft Bearings Using Machine Learning, Jinsiang Shaw, Bingjie Wu

Journal of Marine Science and Technology–Taiwan

Wind turbines are a major trend in the current green energy market. Wind energy is abundant, and if utilized properly, can result in significant reductions in carbon emissions. Therefore, the development of wind power systems is urgently required. However, wind turbines are mainly built in unmanned areas. Regular inspections require substantial manpower and material resources, and doubts regarding the accuracy of the inspected data may occur. Therefore, it is necessary to establish an automatic diagnostic method for determining the remaining useful life (RUL) of a wind turbine to facilitate predictive maintenance. In this study, a multi-class support vector machine (SVM) …

Supply Chain Management For Superyacht Construction In Taiwan, Chun Pong Wong

Journal of Marine Science and Technology–Taiwan

In the last 20 years, Taiwan’s superyacht construction industry has performed well in the global market; however, numerous yacht builders still practice traditional supply chain management (SCM), which is often inefficient and regularly leads to time and cost overruns. This study aimed to answer two research questions: 1) what SCM challenges does the superyacht construction industry face? and 2) what SCM strategies and practices should be adopted to improve the efficacy and profitability of superyacht construction companies?

Numerous studies have explored supply chains (SCs) and SCM, but few have focused on the superyacht construction industry. Superyacht construction projects are highly …

The Impact Of Variable Curing Conditions On The Properties And Microstructures Of Mixtures Of Ground Granulated Blast Furnace Slag And Circulating Q1 Fluidized Bed Combustion Ash, Shao-Heng Hsieh, Wei-Chung Yeih, Ran Huang

Journal of Marine Science and Technology–Taiwan

The use of Portland cement, an important construction material, is encountering growing challenges because of its adverse environmental impacts. In this study, a new hydration system without Portland cement, which blends ground granulated blast furnace slag (GGBFS) and circulating fluidized bed combustion (CFBC) ash, was developed and tested. The variables included the effect of different types of CFBC ash, the mass ratios between CFBC ash and GGBFS, and different curing temperatures. The mortar properties were determined through the compressive strength test, absorption test, shrinkage test, X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The main results were as follows: …

A Marine Gis-Based Alert System To Prevent Vessels Collision With Offshore Platforms, Sheng-Long Kao, Ki-Yin Chang, Tai-Wen Hsu

Journal of Marine Science and Technology–Taiwan

How to effectively use an intelligent aid-to-navigation (AtoN) to prevent ships from accidentally colliding with offshore marine platforms (OMPs) is an important issue for maritime environment. This study proposes a novel collision alert system with three components to process Automatic Identification System (AIS) data in the cloud and broadcast AtoNs to ships in order to avoid collision with OMPs. The first component receives as input fuzzy linguistic variables (vessel size, relative speed, and approach distance) from the AIS data and calculates the radius of the guarding ring. The second component serves a Marine GIS (MGIS), where the system simulates the …

Spatial Distribution Of Pm2.5-Related Premature Mortality In China, Sheng Zheng, Uwe Schlink, Kin-Fai Ho, Ramesh P. Singh, Andrea Pozzer

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

PM_2.5 is a major component of air pollution in China and has a serious threat to public health. It is very important to quantify spatial characteristics of the health effects caused by outdoor PM_2.5 exposure. This study analyzed the spatial distribution of PM_2.5 concentration (45.9 μg/m³ national average in 2016) and premature mortality attributed to PM_2.5 in cities at the prefectural level and above in China in 2016. Using the Global Exposure Mortality Model (GEMM), the total premature mortality in China was estimated to be 1.55 million persons, and the per capita mortality was 11.2 …

Spatial Distribution Of Pm2.5-Related Premature Mortality In China, Sheng Zheng, Uwe Schlink, Kin-Fai Ho, Ramesh P. Singh, Andrea Pozzer

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

PM_2.5 is a major component of air pollution in China and has a serious threat to public health. It is very important to quantify spatial characteristics of the health effects caused by outdoor PM_2.5 exposure. This study analyzed the spatial distribution of PM_2.5 concentration (45.9 μg/m³ national average in 2016) and premature mortality attributed to PM_2.5 in cities at the prefectural level and above in China in 2016. Using the Global Exposure Mortality Model (GEMM), the total premature mortality in China was estimated to be 1.55 million persons, and the per capita mortality was 11.2 …

Making Agriculture Carbon Neutral Amid A Changing Climate: The Case Of South-Western Australia, Ross Kingwell

Climate Science Research Articles

Making Australian agriculture carbon neutral by 2050 is a goal espoused by several agricultural organisations in Australia. How costly might it be to attain that goal, especially when adverse climate change projections apply to agriculture in southern Australia? This study uses scenario analysis to examine agricultural emissions and their abatement via reforestation in south-western Australia under projected climate change. Most scenarios include the likelihood of agricultural emissions being reduced in the coming decades. However, the impact of projected adverse climate change on tree growth and tree survival means that the cost of achieving agricultural carbon neutrality via reforestation is forecast …

Peruvian Fur Seals As Archivists Of El Niño Southern Oscillation Effects, Mickie Rae Edwards, Susana Cardenas-Alayza, Michael Adkesson, Mya Daniels-Abdulahad, Amy Hirons

Marine & Environmental Sciences Faculty Articles

Peru’s coastal waters are characterized by significant environmental fluctuation due to periodic El Niño- La Niña- Southern Oscillation (ENSO) events. This variability results in ecosystem-wide food web changes which are reflected in the tissues of the Peruvian fur seal (Arctocephalus australis). Stable isotope ratios (δ¹³C and δ¹⁵N) in Peruvian fur seal vibrissae (whiskers) are used to infer temporal primary production and dietary variations in individuals. Sea surface temperature anomaly (SSTA) recordings from the Niño 1+2 Index region captured corresponding ENSO conditions. Fluctuations in δ¹⁵N values were correlated to SSTA records, indicating that …

California Drought Outlooks Based On Climate Change Models’ Effects On Water Availability, Lauren Lynam, Thomas Piechota

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Future streamflow in California is evaluated based on eight climate projections models and the effects on water availability. The unimpaired projected streamflow for eleven California rivers, collected from Cal-Adapt, are compared with unimpaired historical flows (1950–2015) using eight climate model projections (2020–2099) identified as representative as possible future scenarios; Warm Dry RCP 4.5, Average RCP 4.5, Cool Wet RCP 4.5, Other RCP 4.5, Warm Dry RCP 8.5, Average RCP 8.5, Cool Wet RCP 8.5, and Other RCP 8.5. Projected drought deficits (or magnitudes), durations, and intensities are statistically tested against historical values to determine significance of differences between past streamflow …

Investigating The Growth Of Algae Under Low Atmospheric Pressures For Potential Food And Oxygen Production On Mars, Leena M. Cycil, Elisabeth M. Hausrath, Douglas W. Ming, Christopher T. Adcock, James Raymond, Daniel Remias, Warren P. Ruemmele

Geoscience Faculty Research

With long-term missions to Mars and beyond that would not allow resupply, a self-sustaining Bioregenerative Life Support System (BLSS) is essential. Algae are promising candidates for BLSS due to their completely edible biomass, fast growth rates and ease of handling. Extremophilic algae such as snow algae and halophilic algae may also be especially suited for a BLSS because of their ability to grow under extreme conditions. However, as indicated from over 50 prior space studies examining algal growth, little is known about the growth of algae at close to Mars-relevant pressures. Here, we explored the potential for five algae species …

Interspecific And Local Variation In Tern Chick Diets Across Nesting Colonies In The Gulf Of Maine, Keenan Yakola, Adrian Jordaan, Stephen Kress, Paula Shannon, Michelle D. Staudinger

United States Geological Survey: Staff Publications

The Gulf of Maine, USA is home to four colonial co-nesting tern species: Least Tern (Sternula antillarum), Common Tern (Sterna hirundo), Arctic Tern (Sterna paradisaea), and the federally endangered Roseate Tern (Sterna dougallii). Over three decades of visual observations of chick provisioning were compiled for a comparative dietary study in the region, including the first detailed descriptions of Least and Roseate Tern chick diets. Three prey groups comprised the majority of chick diets among tern species between 1986–2017: hake (Urophycis spp. or Enchelyopus cimbrius) 28–37% frequency of occurrence (FO), sand lance …

Ionospheric F-Layer Dipole Flute Instability Effects On Electromagnetic Scattering In A Magnetohydrodynamic Plasma, Andrew J. Knisely

Theses and Dissertations

The ionosphere has significant impact on radio frequency (RF) applications such as satellites, over-the-horizon radar, and commercial communication systems. The dynamic processes effecting the behavior of the ionic content leads to a variety of instabilities that adversely affect the quality of RF signals. In the F-layer ionosphere, flute instability persists, appearing as two radial regions of high and low density perturbations elongated along the earth's geomagnetic field lines. The sizes of flute structures are comparable to the wavelengths in the high frequency spectrum. The objective is to characterize the high frequency scattering of an incident field by developing a 3D …

The Imperative For Climate Action At Portland State University, Stephen Percy

Office of the President Publications and Presentations

Portland State University President Stephen Percy announces the formation of the Climate Change Initiative.

Exposure Of Predatory And Scavenging Birds To Anticoagulant Rodenticides In France: Exploration Of Data From French Surveillance Programs, Meg-Anne Moriceau, Sébastien Lefebvre, Isabelle Fourel, Etienne Benoit, Florence Buronfosse-Roque, Pascal Orabi, Barnett A. Rattner, Virginie Lattard

United States Geological Survey: Staff Publications

Wild raptors are widely used to assess exposure to different environmental contaminants, including anticoagulant rodenticides (ARs). ARs are used on a global scale for rodent control, and act by disruption of the vitamin K cycle that results in haemorrhage usually accompanied by death within days. Some ARs are highly persistent and bioaccumulative, which can cause significant exposure of non-target species.We characterized AR exposure in a heterogeneous sample of dead raptors collected over 12 years (2008–2019) in south-eastern France. Residue analysis of 156 liver samples through LC-MS/MS revealed that 50% (78/156) were positive for ARs, with 13.5% (21/156) having summed second-generation …

Riverine And Estuarine Co2-System Studies On The West Coast Of Florida, Christopher S. Moore

USF Tampa Graduate Theses and Dissertations

Coastal and estuarine acidification impacts ecosystem health and economic resources and has both natural and anthropogenic components (Cai et al., 2021). Riverine input is one of several important factors that can influence acidification in coastal ecosystems. Rivers disgorging into coastal environments can create strong gradients, both spatial and temporal, that make accurate CO2-system characterization challenging. The work described in this thesis provides a baseline CO2-system study of four major rivers that flow into Tampa bay with an emphasis on seasonal change. As a second objective, this thesis examines the effects of HgII additions on CO2-system measurements in organic-rich estuarine waters. …

Pre-Earthquake Ionospheric Perturbation Identification Using Cses Data Via Transfer Learning, Pan Xiong, Cheng Long, Huiyu Zhou, Roberto Battiston, Angelo De Santis, Dimitar Ouzounov, Xuemin Zhang, Xuhui Shen

Mathematics, Physics, and Computer Science Faculty Articles and Research

During the lithospheric buildup to an earthquake, complex physical changes occur within the earthquake hypocenter. Data pertaining to the changes in the ionosphere may be obtained by satellites, and the analysis of data anomalies can help identify earthquake precursors. In this paper, we present a deep-learning model, SeqNetQuake, that uses data from the first China Seismo-Electromagnetic Satellite (CSES) to identify ionospheric perturbations prior to earthquakes. SeqNetQuake achieves the best performance [F-measure (F1) = 0.6792 and Matthews correlation coefficient (MCC) = 0.427] when directly trained on the CSES dataset with a spatial window centered on the earthquake epicenter with the Dobrovolsky …