Oceanography and Atmospheric Sciences and Meteorology Commons^™

Investigating Model Solution Correctness For Parameter Uncertainty In Both Objective Function And Constraints, Shangyao Yan, Sin-Siang Wang, Chun-Yi Wang

Journal of Marine Science and Technology–Taiwan

To resolve engineering management problems encountered in the real world, optimization models are usually formulated with some parameter assumptions. Parameter uncertainty, which may arise due to changes in the environment or human error, may thus be incorporated into the objective function and the constraints. However, to simplify the modeling, the values of these parameters are usually set or projected as deterministic values. It is no wonder that the modelling results based on these inaccurate parameters are neither correct nor reliable. Thus, it is important to examine the correctness of the model results in relation to parameter uncertainty. This study aims …

Modular Design And Implementation Of An Automatic Power Factor Regulator For Energy Savings On Fishing Vessels, Chien-Hsing Lee, Shih-Hsien Hsu, Joe-Air Jiang

Journal of Marine Science and Technology–Taiwan

This study describes the experiences of modular design and implementation of an automatic power factor regulator for improving energy efficiency on Taiwanese longline fishing vessels. The load capacities of such vessels are typically divided into three categories, depending on the gross tonnage or fish carrying capacity: less than 100 kW, from 100 kW to less than 250 kW, and larger than 250 kW. For attaining proper power factor improvement, a compensation unit with a total of 30 kVar, 60 kVar and 90 kVar was sized and assembled with capacitors of 10, 15 and 20 kVar to enable control within 12 …

Key Risk Factors Influencing Harbor Tugboat Operations For Kaohsiung Port, Wen-Jui Tseng, Ji-Feng Ding, Chia-Ming Liu, Liou-Yuan Li

Journal of Marine Science and Technology–Taiwan

The harbor tugboat operation is a very important business and process of Kaohsiung port. To ensure the safety of harbor tugboat operations and to reduce the occurrence of accidents, it is an important issue to conduct a risk assessment of tugboat operations for Kaohsiung port. Hence, the main purpose of this paper is employ the analytic hierarchy process (AHP) method to evaluate key risk factors influencing the harbor tugboat operations for Kaohsiung port. At first, a total of three evalu-ation dimensions with 14 preliminary risk factors are gener-ated from literature and interviews of tugboat captains. We then applied the steps …

Free Vibration Analysis Of A Free-Free Single-Tapered Beam Carrying Arbitrary Concentrated Elements Using Modified Mode-Superposition Method (Mmsm), Chia-Chin Wu

Journal of Marine Science and Technology–Taiwan

The literature contains scant information on the free vibration analyses of the loaded single-tapered beams (STBs) (i.e., STBs carrying concentrated elements (CEs)) Furthermore, even when such studies have been performed, they generally only consider the case of constrained (e.g., free-clamped (F-C)) beams. In other words, the problem of unconstrained (e.g., free-free (F-F)) loaded STBs has not yet to be addressed. Thus, the present study employs the modified mode-superposition method (MMSM) to investigate the free vibration characteristics of the F-F loaded STB carrying arbitrary various CEs. The investigation focuses particularly on the natural frequencies and mode shapes of the rigid-body motions …

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, 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, 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, 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, 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, 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, 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, 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 …

Physiological And Molecular Responses Of Eurythermal And Stenothermal Populations Of Zostera Marina L (Eelgrass) To Climate Change, Carmen C. Zayas-Santiago

OES Theses and Dissertations

As CO₂ levels in Earth’s atmosphere and oceans steadily rise, varying organismal responses may produce ecological losers and winners. Increased ocean CO₂ can enhance seagrass productivity and thermal tolerance, providing some compensation for climate warming. However, the consistency of this CO₂ effect across populations of cosmopolitan species such as Zostera marina L. (eelgrass) remains largely unknown. This study analyzed whole-plant performance metabolic profiles and gene expression patterns of distinct eelgrass populations in response to CO₂ enrichment. Populations were transplanted from Nisqually Landing and Dumas Bay, two cold water environments in Puget Sound, WA (USA) that rarely …

The Conservation Status Of The World’S Freshwater Molluscs, M. Böhm, N. I. Dewhurst-Richman, M. Seddon, C. Albrecht, D. Allen, A. E. Bogan, K. Cummings, G. Darrigran, W. Darwall, Kathryn E. Perez

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

With the biodiversity crisis continuing unchecked, we need to establish levels and drivers of extinction risk, and reassessments over time, to effectively allocate conservation resources and track progress towards global conservation targets. Given that threat appears particularly high in freshwaters, we assessed the extinction risk of 1428 randomly selected freshwater molluscs using the IUCN Red List Categories and Criteria, as part of the Sampled Red List Index project. We show that close to one-third of species in our sample are estimated to be threatened with extinction, with highest levels of threat in the Nearctic, Palearctic and Australasia and among gastropods. …

Examining Melt Pond Dynamics And Light Availability In The Arctic Ocean Via High Resolution Satellite Imagery, Austin Wesley Abbott

OES Theses and Dissertations

As the Arctic experiences consequences of climate change, a shift from thicker, multi-year ice to thinner, first-year ice has been observed. First-year ice is prone to extensive pools of meltwater (“melt ponds”) forming on its surface, which enhance light transmission to the ocean. Changes in the timing and distribution of melt pond formation and associated increases in under-ice light availability are the primary drivers for seasonal progression of water column primary production and warming. Observations of melt pond development and distribution require meter scale resolution and have traditionally been limited to airborne images. However, recent advances in high spatial resolution …

Weather And Climate Summary And Forecast: June 2021 Report, Gregory V. Jones

Linfield University Wine Studies Reports

This report provides a summary of the weather and climate forecast for June 2021. It includes forecast information specific to the Pacific Northwest and the western United States, as well as forecast information for other portions of the United States and abroad.

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, 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 …

Evaluating The Fish Aggregation Effect Of Wind Turbine Facilities By Using Scientific Echo Sounder In Nanlong Wind Farm Area, Western Taiwan, Ting-Chieh Huang, Hsueh-Jung Lu, Jia-Rong Lin, Shih-Hsuan Sun, Kou-Wei Yen, Jing-Yi Chen

Journal of Marine Science and Technology–Taiwan

During the stages of construction and operation of the wind power facilities, fishery and fishery resources in the wind farm areas will certainly be changed greatly. One of the major concern is the aggregation effect of wind turbines facility. We use scientific echo sounder together with scuba diving to survey fish aggregations in the wind farm areas. In order to obtain echoes very near the facility, we use tilt beam angle instead of traditional vertical one. Variation of target strength varies while using tilted beam angle were discussed both by ex-situ and in-situ experiment. In ex-situ experiment, we measured TS …

Site Fidelity And Return Trips Of Visually And Olfactorily Inhibited Black Rockfish (Sebastes Schlegelii) Individuals Tracked By Acoustic Telemetry, Mitsuki Kuroda, Yoshinori Tatsu, Yuya Ueda, Hokuto Shirakawa, Kenji Minami, Kazushi Miyashita, Makoto Tomiyasu

Journal of Marine Science and Technology–Taiwan

For fish of the genus Sebastes, which have strong site fidelity, understanding the characteristics of their return trips and how their sensory cues influence behavior will be useful for conservation and resource management. Here, we conducted a behavioral tracking study for the black rockfish Sebastes schlegelii using acoustic telemetry and sensory inhibition. We compared aspects of the return process for individuals in a control group (CNT), and fish in blind (BLD) and olfactory inhibition (OLF) conditions. Nine individuals were released 850 m from the fishing site, and all of them returned. However, the time taken to complete the return varied, …

Geospatial And Acoustic Application In An Artificial Reef Site Of South Korea, Myounghee Kang, Rina Fajaryanti, Kyounghoon Lee, Eun-A Yoon, Woo-Seok Oh, Eunbi Min, Young-Jae Shin, Yong-Suk Choi, Byung-Ho Yi, Hui Zhang, Doojin Hwang

Journal of Marine Science and Technology–Taiwan

Artificial reefs are important since they provide additional habitat leading to increasing abundance and biomass of marine biota. In a Bukchon artificial reef, Jeju Island, South Korea, environment data, artificial reef properties, and acoustic data in four seasons were integrated to visualize and examine their connections using a geographic information system (GIS). As a result, regarding the spatial and temporal distributions of fishes, January had the lowest Nautical Area Scattering Coefficient (NASC, m2/nm2) and June had the highest NASC, and relatively high NASC was observed from 5 to 30 m deep throughout seasons. The influential circle (effective distance from reef) …

Rapid Warming Events In A Small Coastal Upwelling Embayment, Tatjana E. Ellis

Physics

Temperature variability in the nearshore coastal ocean influences various biological processes and can drive changes in biodiversity and habitat range. Despite recent progress, there are still significant gaps in the understanding of drivers of temperature variability in upwelling bays, particularly at higher frequencies. In this study, we analyzed a decade of nearshore temperature measurements both inside and outside a small coastal embayment located in central California [San Luis Obispo (SLO) bay], as well as temperature data from satellites, to characterize rapid warming events. We found that rapid warming events, defined using rates of temperature change across different thresholds, occurred more …

My Interdisciplinary Perspective On Climate Change [Natural Sciences], Richa Gupta, Tuli Chatterji, Tao Chen, Rebecca Schwartz

Open Educational Resources

This assignment titled “My Interdisciplinary Perspective on Climate Change” was developed in Fall 2020 as the signature assignment of the STEM Learning Community LC50 for students enrolled in the Biology program of the Natural Sciences department, at LaGuardia Community College, CUNY. The assignment targets Integrative Learning and Global Learning Core Competencies, and Digital/Oral Communication Abilities.

For this STEM Cluster, “Climate Change” is the shared theme that connects learning from the different disciplines and helps build students’ overall knowledge on an imperative issue that our planet currently faces. Work on this assignment entails a narrated digital student presentation on the various …

Comparison Of Fish Assemblages Aggregated By Artificial Reefs Using Scuba Diving And Acoustic Surveys, Hsueh-Jung Lu, Jia-Rong Lin, Ting-Chieh Huang, Sunarti Sinaga

Journal of Marine Science and Technology–Taiwan

To determine the aggregation effect of artificial reefs (ARs), we conducted surveys in 16 artificial reefs in Taiwan by using the scientific echo sounder, Simrad EY-60 (200 KHz), along with sighting by scuba divers. Scuba diving was conducted within the reef structures (r ¼ 20 m), whereas acoustic surveys were conducted over a wider range (r ¼ 100 m), with five repeating transects over the ARs. We compared the results obtained from the two methods among 16 artificial reefs in the coastal waters of Taiwan to determine the consistency of the quantitative information between the two methods and to investigate …

Study On The Behavior Of Peled (Coregonus Peled ) Around A Set Net By Ultrasonic Biotelemetry System In A Plateau Lake, China, Jing Liu, Keiichi Uchida, Leiming Yin, Yong Tang, Yoshinori Miyamoto, Binbin Xing

Journal of Marine Science and Technology–Taiwan

Sayram Lake is a plateau cold-water lake located in northwestern China. Peled (Coregonus peled ) was introduced to Sayram Lake from Russia in 1998. The behavior characteristics of peled in Sayram Lake are important for fishery resource proliferation, effective fishing, and sustainable development. In this study, we used an ultrasonic biotelemetry system to track the fish around a large-scale set net in Sayram Lake. The purpose of this study is to study the behavior characteristics of the peled and to provide suggestions for the improvement of the set net. The results showed that the fish released in the playground of …

Seasonal Dynamics In Fish Distribution And Abundance Revealed By An Acoustic Survey In Coastal Waters Of The Suzu Area, Kochi Prefecture, Japan, Yanhui Zhu, Kenji Minami, Yuka Iwahara, Kentaro Oda, Koichi Hidaka, Osamu Hoson, Koji Morishita, Sentaro Tsuru, Masahito Hirota, Hokuto Shirakawa, Kazushi Miyashita

Journal of Marine Science and Technology–Taiwan

For Japan's fishery, it is essential to conduct sustainable and efficient fishery owing to the decline in fish catch as well as the fisher population. To obtain information that contributes to sustainable and efficient fishery, we researched appropriate set-net locations with regard to fish distribution, abundance, and environmental characteristics. We conducted surveys from 2017/5 to 2018/2 in the Suzu coastal area, Kochi Prefecture, where the only main industry is set-net fishery. We investigated the seasonal relationships between fish school characteristics, including distribution and size, and marine environmental conditions in the Suzu coastal area, using a quantitative echo sounder (KSE300 SONIC, …

Development Of A Biomass Assessment Method Using Fisheries Echo Sounder For Monitoring Whitebait Fishery In Shizuoka Prefecture, Japan, Kenichi Kobayashi, Yanhui Zhu, Daichi Oshiyama, Kenji Minami, Hokuto Shirakawa, Kazushi Miyashita

Journal of Marine Science and Technology–Taiwan

Coastal fisheries constitute the second most important sector in fishery production in Japan, following offshore fisheries. Thus, spatial evaluation of coastal fishing grounds and understanding of the changes in biomass are important for the sustainable use of fishing resources. For the assessment of spatial fish biomass, a quantitative echo sounder is used, but such a device is not mass produced and involves a high cost. In the present study, we examined the feasibility of biomass assessment using typical commercial fisheries echo sounders that are widely used and cheaper than quantitative echo sounders. Therefore, we aimed to verify the validity of …

Acoustic Survey For Estimating Density Of Anchovy Schools In The South Sea Of Korea, Eunbi Min, Eun-A Yoon, Sung-Tae Kim, Seong Yong Moon, Hyun Woo Kim, Shelly Salim, Taejong Kang, Doo-Jin Hwang

Journal of Marine Science and Technology–Taiwan

No abstract provided.

Estimating The Sampling Efficiencies Of A Framed Midwater Trawl And Ring Net For Zooplankton Using An Acoustic Method, Zhen Lu, Tohru Mukai, Yasuzumi Fujimori, Kohji Iida

Journal of Marine Science and Technology–Taiwan

It is well known that there is bias using different sampling gear, such as a framed midwater trawl (FMT) and a ring net, when measuring the density and length distribution of target species. This limit is characterized by the sampling efficiency of the gear. Acoustic monitoring can be used to determine the sampling efficiencies of this gear, as its noninvasive, wide-range sweeps provide more reliable estimates of absolute abundance of the target species. The density measured by the gear can then be standardized by multiplying the initial density measurement by the derived sampling efficiency. In this study, we compared the …

In Situ Broadband Acoustic Measurements Of Age-0 Walleye Pollock And Pointhead Flounder In Funka Bay, Hokkaido, Japan, Kohei Hasegawa, Naizheng Yan, Tohru Mukai

Journal of Marine Science and Technology–Taiwan

Measurements of the broadband acoustic backscattering from fish should improve acoustic discrimination between species. The pulse compression processing of broadband systems can be used to measure acoustic backscattering with high range resolution and improve signal-to-noise ratio. This may increase opportunities for in situ target strength (TS) measurements, the preferred method of collecting TS data. To evaluate the availability of TS spectra for acoustic discrimination, three Simrad EK80 wideband transceivers and split-beam transducers of 70, 120, and 200 kHz were used to collect in situ frequency responses of TS from age-0 juvenile walleye pollock and pointhead flounder, a swimbladderless flat-fish, distributed …