Fresh Water Studies Commons^™

A Hybrid Finite Difference Method For Singularly Perturbed Delay Partial Differential Equations With Discontinuous Coefficient And Source, Nitika Sharma, Aditya Kaushik

Journal of Marine Science and Technology–Taiwan

The article presents a hybrid finite difference scheme to solve a singularly perturbed parabolic functional differential equation with discontinuous coefficient and source. The simultaneous presence of deviating argument with a discontinuous source and coefficient makes the problem stiff. The solution of the problem exhibits turning point behaviour across discontinuity as tends to zero. The hybrid scheme presented is a composition of a central difference scheme and a midpoint upwind scheme on a specially generated mesh. At the same time, an implicit finite difference method is used to discretize the time variable. Consistency, stability, and convergence of the presented numerical approach …

Simulating And Predicting Offshore Oil Spills By Using Cellular Automata, Lin Liu, Wanwu Li, Yumeng Cui, Guanghui Hu, Hang Li

Journal of Marine Science and Technology–Taiwan

In recent years, offshore oil spill accidents have caused substantial damage to both marine organisms and marine ecology. Accurate simulation and prediction of oil spills could provide a scientific basis for assessing losses due to oil spills and provide support for emergency decisions regarding oil spills. We analyzed the advantages and disadvantages of existing oil spill models and constructed an offshore oil spill model based on cellular automata (CA). By considering both the flow field and wind field, we formulated new CA rules for the diffusion and drift of a pollution zone, and in our model, the cellular state in …

Design And Testing Of A Bearing Less Piezo Jet Micro Heat Sink, Rong-Tsu Wang, Jung-Chang Wang, Sih-Li Chen

Journal of Marine Science and Technology–Taiwan

The present study utilized piezoelectric ceramics (PC) as actuators to design five new piezoelectric heatsinks and preliminarily investigated the different design types and their operating conditions, such as the frequency, placement distance, thickness between piezoelectric sheets, piezoelectric sheet size, and noise produced. The results showed that when the micro heatsink bearingless piezo jet was placed too close to the heat source, the high temperature sucked back the surrounding fluids, causing the fluid chamber temperature to rise and the cooling effect to be reduced. Therefore, the heatsink should be placed between 10 and 20 mm from the heat source. With the …

The Effect Of Water Management And Ratoon Rice Cropping On Methane Emissions And Harvest Yield In Arkansas, Marguerita Leavitt

Graduate Theses and Dissertations

Sustainable intensification of rice farming is crucial to meeting human food needs while reducing environmental impacts. Rice produces 8% of all anthropogenic CH4, which is a potent greenhouse gas. CH4 emissions can potentially be reduced by cultivation practices that minimize the number of days the fields are saturated, such as dry-seeding instead of water-seeding and irrigation using the alternate wetting and drying (AWD) technique instead of delayed, continuous flooding (DF). Ratoon cropping, wherein a second crop of rice is grown from the harvested stubble of the first crop, can be used to produce additional yield with minimal labor, but may …

Nitrogen Fixation Rates In Forested Mountain Streams: Are Sediment Microbes More Important Than Previously Thought?, Erica A. H. Bakker, Carmella Vizza, Clay Arango, Sarah S. Roley

Biology Faculty Scholarship

1. Biological nitrogen (N) fixation, the microbial conversion of N₂ gas to ammonia, makes N available to food webs. Low-N streams often have a high relative abundance of N-fixing taxa, suggesting that N fixation is an important N source in these systems. Despite this potential, stream N fixation has not been well-characterised, particularly compared to lakes and marine environments. One unknown is the relative contributions of various N-fixing organisms, particularly heterotrophic microbes.
2. In low-N streams in the Cascade Mountains (Washington, USA), three groups of N-fixers predominate: cyanobacteria (Nostoc paramelioides) colonies that house a midge symbiont (Cricotopus spp.), …

Developing A Miniature Smart Boat For Marine Research, Michael Isaac Eirinberg

Computer Engineering

This project examines the development of a smart boat which could serve as a possible marine research apparatus. The smart boat consists of a miniature vessel containing a low-cost microcontroller to live stream a camera feed, GPS telemetry, and compass data through its own WiFi access point. The smart boat also has the potential for autonomous navigation. My project captivated the interest of several members of California Polytechnic State University, San Luis Obispo’s (Cal Poly SLO) Marine Science Department faculty, who proposed a variety of fascinating and valuable smart boat applications.

Inter-Annual Variability In Growth And Maturation Of The Swordtip Squid Uroteuthis Edulis In Yilan Bay Off Northeastern Taiwan, Jing-Yu Chen, Tzu-Yun Ching, Chih-Shin Chen

Journal of Marine Science and Technology–Taiwan

The swordtip squid Uroteuthis edulis, distributed in the temperate and tropical neritic waters in the Indo-Pacific region, is a crucial component of marine ecosystems and is a target species of fisheries in the Northwest Pacific. Although studies have elucidated the growth and maturation of the squid in the southern East China Sea (ECS) shelf, few have assessed the population biology of the squid in waters in the vicinity of the southern ECS. We collected samples of swordtip squid from a trawler in Yilan Bay (YLB) between January 2011 and December 2012 to examine the growth and maturation of the squid …

Study On The Improved Radiation Boundary Conditions Based On The Quadratic B-Spline Rankine Panel Method, Ming-Chung Fang, Chun-Hsien Wu

Journal of Marine Science and Technology–Taiwan

This study presents a higher-order Rankine source method that is based on a biquadratic B-spline scheme with an improved radiation boundary condition. This method solves flow problems under all conditions, where , including the undercritical condition ( < 0.25); this condition is present when a ship undergoes slow translational motion. The proposed method is thus more flexible than the many Rankine-source models in the literature that are applicable only to the overcritical condition ( > 0.25). Specifically, the improved radiation boundary condition is derived from upstream Seto radiation boundary conditions and by incorporating the Rayleigh damping distribution over a free surface; the improved condition is explicit and efficient for solving flow problems. In evaluations, the proposed method yields accurate solutions for unsteady flows, which are produced by an oscillating, translationally moving submerged singularity. The method is also compared …

Sensitive Analysis Of The Static Response Of Compliant Vertical Access Risers, Fuheng Li, Haiyan Guo, Xiaomin Li, Honglu Gu

Journal of Marine Science and Technology–Taiwan

Compliant vertical access risers (CVARs) are considered as efficient and robust alternative options to achieve cost efficiency and safety. Design uncertainties emerge owing to the limited understanding of the effects of various parameters related to the structural properties and marine loads. In this paper, a reasonable three-dimensional (3D) numerical model of CVAR with internal flow is presented based on the slender rod theory. Accordingly, the finite element method combined with a Newton-Raphson scheme is employed to discretize and solve the equations. A sensitivity analysis is performed to investigate the influence of the structural and external load parameters on the static …

Influence Of Boundary Conditions And Internal Fluid Types On Dynamic Characteristics Of A Deepwater Riser, Lei Guo, Zong-Ming Zhu, Zhong-Jian Pan, Zhi-Ming Guo

Journal of Marine Science and Technology–Taiwan

Deepwater Steel Catenary Riser (DSCR) is the key structure of oil and gas production system in the ocean. To design an optimized DSCR system, the dynamic characteristics of the DSCR are analyzed by setting some different boundary condi-tions and internal fluid types. The main vibration mode of the DSCR is found orthogonal to both mass and stiffness according to the normalization condition of the main mode, and then the regular mode function and the jth order principal stiffness Kpj are obtained. Under different initial conditions, the transverse responses of DSCR represented by regular coordinates under arbitrary excitation are obtained. Then, …

Variance Of Td-Mosaic Dual-Vortex Interactions Between In-Fa And Cempaka (2021) In The North Pacific, Tsorng-Lin Chia, Guang-Yang Pan, Ji-Chyun Liu

Journal of Marine Science and Technology–Taiwan

A study of the different types of dual-vortex interactions or “Fujiwara effects” between two storms is crucial for considerably improving weather forecasts. This study combined remote sensing images, empirical formulas based on the possibility of storm interaction (Liou–Liu formula), and vector addition techniques to accurately analyze In-Fa and Cempaka typhoons and the surrounding weather patterns during the 2021 typhoon season in the North Pacific. Although the distance separating the typhoons In-Fa and Cempaka was 1,800–2,040 km, the influence of middle air flow and a tropical depression (TD) caused a "vector superposition TD-mosaic double-vortex" interaction between the two typhoons. Therefore, this …

Optimal Deployment Of Flood Emergency Response Materials Under Stochastic Demands, Shangyao Yan, Jenn-Rong Lin, Chia-Fu Ku

Journal of Marine Science and Technology–Taiwan

This study aims to develop a planning model for the deployment of flood emergency response materials under stochastic demands. For ease of modeling, a deterministic demand model is first proposed, from which the stochastic model is further extended. These models are used to determine the allocation of materials the transport truck routes and distribution of the stockpiled materials to emergency sites. The models are formulated as multiple integer network flow problems with special side constraints which are characterized as NP-hard in terms of optimization. To solve the complicated stochastic model efficiently, we also develop a solution algorithm based on a …

How Flow Regime Affects Predator-Prey Relationships Of Stream Darter And Shiner Species, Anna E. Richardson

Biological Sciences Undergraduate Honors Theses

Analysis of the interactions between abiotic and biotic factors of environments and ecosystems is a highly valued area of research. This study focuses on the interactions between the biotic component of predation and foraging of certain stream fish species and the abiotic component of the flow regime that those species reside in. Gut content analysis followed by statistical calculations in the form of t-tests and chi -quared tests were performed on two fish species who both inhabited a stream with a groundwater flashy flow regime as well as a stream with a runoff flashy flow regime. The research showed that …

The Effects Of Water With Anti-Inflammatory Capabilities (Wac) On Circulating Inflammatory Biomarkers At Rest And Following Resistance Exercise, Brittany Martin

Health, Human Performance and Recreation Undergraduate Honors Theses

Purpose: To determine the effects of waters with anti-inflammatory capabilities (WAC) influence circulating inflammatory biomarkers at rest and following resistance exercise. Methods: Participants completed a heavy lifting protocol and drank water with anti-inflammatory capabilities for a total of six weeks. Blood samples were taken at different at 9 different time intervals to assess concentrations of anti-inflammatory markers and to quantify inflammatory biomarkers. Those time intervals included pre-AHREP 1 and post-AHREP 1, 24-hr post-AHREP 1, 48-hr post-AHREP 1, 3-week check-up, pre-AHREP 2, post-AHREP 2, 24-hr post-AHREP 2, and 48-hr post-AHREP 2. Background: The biomarkers that were focused on were: IL-6 …

Exploring The Effects Of Varied Land Use On Elemental Concentrations Within Streams, Logan Jennings

Biological and Agricultural Engineering Undergraduate Honors Theses

It is well documented that human activity influences the chemistry of surrounding waters. As such, it is possible that there is a link between land use within a watershed and the chemical composition of the stream. The objectives of this study are to determine if varied land use does affect the concentrations of macronutrients and trace elements present in the streams of Northwest Arkansas, and if so, to determine what extent urban and agricultural development are responsible for these changes. Water samples were collected across 19 streams in the Northwest Arkansas region between January and March of 2022. Water samples …

Aquatic Diversity In A Changing Tropical Andean Glacierized Catchment: Macroinvertebrates Reveal Possible Important Consequences To The Chimborazo Region As Glaciers Recede And The Climate Continues To Change, Tanner Thomas

Independent Study Project (ISP) Collection

Tropical Andean glaciers are retreating rapidly, and their disappearance will have drastic consequences for the people and ecosystems that depend on them. While they have begun to receive the attention they deserve in scientific literature, much is still not known. Majority of these investigations have taken place on the Volcán Antisana, while other important glacierized systems, like the Volcán Chimborazo have received little attention. This investigation aimed to a) evaluate the possible effects of glacier loss and climate change on aquatic ecosystems by comparing glacial meltwater, non-glacial and mixed streams, and b) to evaluate the effects of pasture intensity on …

Commodity Prices, Climate And The High Plains Aquifer, Richard K. Perrin, Lilyan E. Fulginiti, Felipe Silva, Karina A. Schoengold

Cornhusker Economics

Crop prices and energy prices can affect the water level in an aquifer? Absolutely, yes, because over time, they affect the amount withdrawn for irrigation. Our recent research confirms that effect and provides estimates of the size of the effect on the High Plains Aquifer (HPA). The HPA underlies parts of eight states and 208 counties in the west-central United States (see Figure 1). This region produces more than 9% of US crop sales and relies on the aquifer for irrigation. These withdrawals for irrigation have contributed to a diminished stock of water in the aquifer that varies considerably across …

A Non-Iteration Solution For Solving The Backward-In-Time Two-Dimensional Burgers’ Equation With A Large Reynolds Number, Yen-Shen Chang, Yung-Wei Chen, Chein-Shan Liu, Jiang-Ren Chang

Journal of Marine Science and Technology–Taiwan

This article proposes a noniteration solution based on the Lie-group shooting method (LGSM) to solve the backward-in-time two-dimensional Burgers’ equation with a large Reynolds number. The backward problem is famous for seriously ill-posed cases because the solution is generally unstable and highly dependent on the input data. Small perturbations in the input data, such as random errors inherent to the measurements in the analysis, can cause large oscillations in the solution. To handle a large Reynolds number under long time spans, it is very difficult to integrate towards the time direction. To avoid time integration and numerical iteration, the noniteration …

Polyketides And Terpenes In Marine Microalgae: Ecological Roles And Mechanisms Of Biosynthesis, Yunxuan Xie, Mohammad Elsheikh

Journal of Marine Science and Technology–Taiwan

Marine microalgae comprise a large number of polyketides and terpenes identified to date with highly diverse molecular scaffolds and the biological activities (Kalaitzis et al., 2010). These compounds play significant roles in marine food web and nutraceutical supplementation in marine animals. Compounds of this class are often synthesized by gene clusters with dedicated domains responsible for carbon chain extension and modification. The unique molecular structure of these compounds encourages people to investigate their biosynthetic mechanisms in-depth. In this review, we summarize relevant articles to unravel the shared mechanisms of these compounds to further understand the variety of domain organizations and …

Unbaited Light-Emitting Diode Traps Performance For Catching Orange Mud Crabs, Muhamad Naimullah, Kuo-Wei Lan, Mhd Ikhwanuddin, Adnan Amin-Safwan, Wei-Yu Lee

Journal of Marine Science and Technology–Taiwan

Mud crabs (Scylla spp.) are a vital fishery resource and targeted for a valuable source of income for coastal communities throughout the Indo-Pacific region. Baited traps are a considerable expense in crustacean fishing. Hence, the present study was performed to investigate the catchability of Scylla olivacea in response to light-emitting diodes (LEDs) in captivity and field conditions. We used a new experimental setup in the captivity condition that revealed most S. olivacea were attracted to green, blue, and white LED lights and no attractive effect by red LED lights similar to the controls. Field studies have shown that the catch …

Catch And Effort Standardization For Taiwanese Swordtip Squid Uroteuthis Edulis Fisheries In The Southern East China Sea, Ke-Yang Chang, Yu-Jie Hsu, Tzu-Yun Ching, Cheng-Hsin Liao, Chih-Shin Chen

Journal of Marine Science and Technology–Taiwan

The swordtip squid Uroteuthis edulis is a neritic squid species that is widely distributed within the coastal waters of subtropical and tropical Indo-western Pacific regions. This squid is a commercially important species throughout its distribution range and plays a critical role in marine ecosystems. Stock assessments of the squid in the East China Sea (ECS) are scarce, although it is crucial information for the sustainability of the squid and relevant fisheries. The squid was harvested by various fisheries in the southern ECS, which could restrict methods for catch-effort standardization. In this study, catch-effort data of Taiwanese swordtip squid fisheries in …

Uniform Torsion Analysis Of Composite Shafts Using Point Collocation Method Based On Pascal Polynomials, Chih-Wen Chang, Jyh-Hong Wu, Ying-Ru Lin, Yu-Feng Lin, Nan-Nong Huang

Journal of Marine Science and Technology–Taiwan

Torsion bars are important elements in the marine structure applications. The usage of the composite torsion bars has increased recently because it takes advantage of the different material property of each constituent. The current research focuses mainly on the uniform warping analysis of composite torsion shafts by using the point collocation method (PCM). The PCM is based on Pascal's triangle polynomial expansion and coupled with subdomain technique that is indispensable for the analysis of composite bars. In addition to satisfying the field equation (Laplace equation for warping function) and traction-free boundary condition for each component, the continuity conditions in both …

Local Reinforcement Design And Safety Factor Evaluation Of Elliptical Hatch Of Pressure Hull, Guang-Min Luo, Jun-Wei Chen

Journal of Marine Science and Technology–Taiwan

A pressure hull is the primary pressure-resistant structure of a submarine. To safeguard the compressive strength of such a hull, local structural reinforcement is required for various hatches on the hull. Hatches are commonly reinforced through increasing the thickness of the hull regions around them; alternatively, hatch nozzle walls are connected with stiffened frames to maintain the continuity of reinforced structures. This study focused on a pressure hull with an elliptical hatch. A PD-5500 cylindrical pressure hull was used to design a cylindrical pressure hull structure, and a model of hatch nozzle reinforcement was designed using the Boiler and Pressure …

Effects Of Dietary Lipid, L-Carnitine And L-Lysine Supplementation On The Growth Performance And Body Composition Of Epinephelus Lanceolatus Larvae, Jen-Hong Chu, Yu-Cong Hong, Angela Chien, Shyn-Shin Sheen

Journal of Marine Science and Technology–Taiwan

The effects of different combinations of dietary lipid, L-carnitine and L-lysine on the growth performance and fatty acid profiles of larval grouper Epinephalus lanceolatus were evaluated. Eight treatment diets were formulated based on a 2x2x2 factorial design, namely 5 and 14% dietary oil mixture (3:1 fish oil/soybean oil), 0 and 0.5% L-carnitine and 0 and 2.83% L-lysine. Each diet was randomly assigned to triplicate groups of ten 0.08g E. lanceolatus larvae for 42 days. The grouper larvae fed with diets containing 14% lipid had significantly higher weight gain percentages than those fed with diets containing 5% lipid. The weight gain …

Detecting The Feeding Habitat Zone Of Albacore Tuna (Thunnus Alalunga) In The Southern Indian Ocean Using Multisatellite Remote Sensing Data, Sandipan Mondal, Yang-Chi Lan, Ming-An Lee, Yi-Chen Wang, Bambang Semedi, Wan-Ya Su

Journal of Marine Science and Technology–Taiwan

Remote sensing is an effective method for identifying potential feeding habitat zones. Spatial and temporal distribution patterns of albacore (ALB) tuna were studied using Taiwan longline fisheries data from 2009 to 2014. A generalized additive model (GAM) was used to compile a fishery database and statistically explore the relationship between distribution and environmental factors. Sea surface temperature (SST), sea surface chlorophyll-a concentration (SSC), sea surface salinity (SSS), sea surface height (SSH), mixed layer depth (MLD), and eddy kinetic energy (EKE) were examined. The results indicated SST as the largest contributor on ALB distribution, followed by SSS and SSC. Catches per …

Japanese Consumer Preference For Raw Fish: Best–Worst Scaling Method, Takahiro Sajiki, Yu-Heng Lu

Journal of Marine Science and Technology–Taiwan

Given the declining consumption of fish and shellfish in Japan, it is essential to better understand consumer needs to design policies that increase consumption. Therefore, we clarify the relative degree of importance Japanese consumers place on various attributes of raw fish during purchase based on a questionnaire survey employing best–worst scaling. We find that consumers prioritize freshness, price, taste, appearance, safety, seasonality, ease of cooking and eating, nutrition, origin, wild fish, and effect on natural environment and ecosystem, in that order. Wild fish has unexpectedly low importance, although Japanese consumers conventionally purchase captured fishery products rather than cultured ones. The …

Diel Vertical Distribution Patterns Of Pelagic Fish Larvae In Yilan Bay, Taiwan, Yi-Chen Wang, Su-Chen Tsai, Wen-Yu Chen

Journal of Marine Science and Technology–Taiwan

To study the diel migration distribution of larval fish in an area adjacent to the Kuroshio Current, samples were collected from six depths by using a Motoda horizontal net at a fixed station in Yilan Bay on July 30 and 31, 2007. A total of 591 larval fish were collected and assigned to at least 34 families and 57 species. The first five dominant species were Benthosama pterotum (40.95%), Diaphus B type (12.18%), Callionymidae spp. (8.46%), Gobiidae spp. (6.60%), and Apogonidae spp. (4.0%). The density of larval fish varied across time. The maximum larval density was 1220.34 individuals/1000 m3 at …

Long-Term Variation Of Sea Surface Temperature In Relation To Sea Level Pressure And Surface Wind Speed In Southern Indian Ocean, Sandipan Mondal, Ming-An Lee, Yi-Chen Wang, Bambang Semedi

Journal of Marine Science and Technology–Taiwan

Sea surface temperature (SST) is an essential parameter associated with fish habitat and changes in oceanic conditions. Long-term SST variation in relation to sea level pressure (SLP) and surface wind speed (SWS) was observed based on the National Oceanic and Atmospheric Administration (NOAA) data of southern Indian Ocean. Mean monthly time series showed that February and November were the warmest and coolest months, respectively. Spatial distribution showed that 0°S–30°S was warm with SST of 20°–30°C, which was higher than that at all other places throughout the year. SLP (> 1010 millibar) and SWS (> 12 m/s) were high at 20°S–40°S …

Economic Conditions For New Entrants In Coastal Fishing In Miyazaki Prefecture, Japan, Takahiro Sajiki, Yu-Heng Lu, Norie Nishiguchi, Sonomi Akamine, Masaharu Nishiguchi

Journal of Marine Science and Technology–Taiwan

A significant decrease in the number of fishery workers is be-coming a problem in Japan. For new entrants to become estab-lished in the region, they must be profitable as fishing busi-nesses. Using the case of Miyazaki prefecture in Japan, this paper identifies the economic conditions required to make longline fishing and bottom gillnet fishing profitable by ap-plying the net present value (NPV) method. When operating on 200 days, which is the guideline for new entrants in longline fishing, if the value of investment is less than 44.1% of the minimum required, the investment will not provide positive returns. However, the …

Raw Garlic (Allium Sativum) Improves Nonspecific Immune Responses And Resistance Against Vibrio Alginolyticus Infection In Grouper (Epinephelus Coioides), Huai-Ting Huang, Po-Tsang Lee, Zhen-Hao Liao, Cheng-Ting Huang, Hsiang-Yin Chen, Zhi-Gu Huang, Fan-Hua Nan, Yu-Sheng Wu

Journal of Marine Science and Technology–Taiwan

Garlic contains various nutrients and healthful ingredients. The content of garlic products is closely related to their processing methods, and each compound has specific biological effects. Allicin, a heat labile compound, is considered the most important factor in garlic. Garlic powder is commonly prepared by subjecting raw garlic to thermal processing before being grounded into powder,and it is of interest to compare the biological activity of garlic powder with raw garlic in fish. This study investigated immune effects of raw garlic and garlic powder on groupers (Epinephelus coioides). Although raw garlic and garlic powder did not promote growth performance of …