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Assessing The Rates Of Post-Depositional Change Within 2004 Indian Ocean Sediments: Implications For Long-Term Records Of Paleotsunamis, Lillian Pearson 2021 The University of Southern Mississippi

Assessing The Rates Of Post-Depositional Change Within 2004 Indian Ocean Sediments: Implications For Long-Term Records Of Paleotsunamis, Lillian Pearson

Master's Theses

Foraminifera are commonly used to examine patterns of tsunami inundation occurring over centennial to millennial timescales, but the impacts of post-depositional change on geologic reconstructions are unknown. In Sumatra, the taphonomic character (i.e., test surface condition) of a foraminifer can deteriorate over time, rendering them unidentifiable, and even dissolve them entirely. Here I investigate the rates of post-depositional change of foraminiferal assemblages found within the 2004 Indian Ocean Tsunami (IOT) deposit over a 15-year time interval in Aceh, Indonesia in a vegetated open coastal plain (Site 1: Pulot) and an unvegetated protected coastal cave (Site 2). I identified two zones …


A Biological Assessment Of Oyster Restoration Mats Throughout The Indian River Lagoon: Changes In Community Composition And Filtration Capacity Of Living Docks, Morgan Katherine Gilligan 2021 Florida Institute of Technology

A Biological Assessment Of Oyster Restoration Mats Throughout The Indian River Lagoon: Changes In Community Composition And Filtration Capacity Of Living Docks, Morgan Katherine Gilligan

Theses and Dissertations

Like many estuaries worldwide, the Indian River Lagoon (IRL), has seen a decline in resources and overall water quality due to human activities. There is a growing interest in implementing ecological engineering methods to restore water quality. One such method is the construction and deployment of oyster restoration mats on dock pilings, known as the Living Docks program. This community driven program was founded at Florida Tech with the goal of promoting the growth of filter feeding benthic organisms to improve local water quality. Since 2013, twelve docks have been deployed in the central IRL, spanning from Cape Canaveral (28º …


Novel Application Of 210po-210pb Disequilibria To Date Snow, Melt Pond, Ice Core, And Ice-Rafted Sediments In The Arctic Ocean, Mark Baskaran, Katherine Krupp, Mark Baskaran 2021 Department of Environmental Science and Geology, Wayne State University, Detroit, MI

Novel Application Of 210po-210pb Disequilibria To Date Snow, Melt Pond, Ice Core, And Ice-Rafted Sediments In The Arctic Ocean, Mark Baskaran, Katherine Krupp, Mark Baskaran

Environmental Science and Geology Faculty Research Publications

We collected surface ocean water, snow, grab ice, ice core, melt pond and ice-rafted sediment (IRS) from 5 ice stations during the Western Arctic US GEOTRACES cruise (USGCG Healy; August 10 – October 7, 2015) and analyzed for 210Po (T1/2 = 138.4 days) and 210Pb (T1/2 = 22.3 years) in dissolved and particulate phases (snow, grab ice, ice core, surface seawater) to investigate the 210Po:210Pb disequilibria in these matrices. Thirteen aerosol samples, using a large-volume aerosol sampler (PM10), from Dutch Harbor, AK to North Pole, were also collected and analyzed for 210Po/210Pb to quantify the atmospheric depositional input to the …


210po And 210pb As Tracers Of Particle Cycling And Export In The Western Arctic Ocean, Wokil Bam, Kanchan Maiti 2021 Department Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA

210po And 210pb As Tracers Of Particle Cycling And Export In The Western Arctic Ocean, Wokil Bam, Kanchan Maiti

Environmental Science and Geology Faculty Research Publications

The distribution and vertical fluxes of particulate organic carbon and other key elements in the Arctic Ocean are primarily governed by the spatial and seasonal changes in primary productivity, areal extent of ice cover, and lateral exchange between the shelves and interior basins. The Arctic Ocean has undergone rapid increase in primary productivity and drastic decrease in the areal extent of seasonal sea ice in the last two decades. These changes can greatly influence the biological pump as well as associated carbon export and key element fluxes. Here, we report the export of particulate organic and inorganic carbon, particulate nitrogen …


Liner Sailing Speed Optimization Considering Wind And Waves, Zhaokun Wei, Xinlian Xie, Tiantian Bao 2021 College of Transportation, Shandong University of Science and Technology, Qingdao, China

Liner Sailing Speed Optimization Considering Wind And Waves, Zhaokun Wei, Xinlian Xie, Tiantian Bao

Journal of Marine Science and Technology–Taiwan

This paper proposes a new sailing speed optimization problem considering sea conditions such as wind and waves for a container shipping company. Since wind and waves, as exterior factors, can reduce speed, more power is employed as compensation to maintain regular service frequency and avoid delay, resulting in additional bunker consumption and higher cost. Hence, it is necessary to optimize the sailing speed according to the wind and waves. A power model was built to determine the reduced speed caused by the wind and waves for quantifying the speed reduction. On the basis of the proposed model, we developed a …


A Bilevel Mathematical Approach For The Empty Container Repositioning Proble With A Sharing And Exchanging Strategy In Liner Shipping, Dung-Ying Lin, Chieh-Ju Juan 2021 Department of Industrial Engineering and Engineering Management, National Tsing Hua University, Hsinchu City, Taiwan

A Bilevel Mathematical Approach For The Empty Container Repositioning Proble With A Sharing And Exchanging Strategy In Liner Shipping, Dung-Ying Lin, Chieh-Ju Juan

Journal of Marine Science and Technology–Taiwan

In the maritime industry, the management of empty containers is a significant issue whose costs account for a large proportion of the total world fleet running costs. To reduce repositioning activities and increase cost effectiveness, this paper proposes a solution framework considering empty container sharing and exchanging strategies to coordinate the shipping lines in a maritime transportation network. The proposed solution framework considers an empty container matching platform company and a group of shipping lines in a given shipping network. Because of the interactive relationship between the two parties, the proposed problem is formulated as a bilevel programming problem, and …


Investigating Model Solution Correctness For Parameter Uncertainty In Both Objective Function And Constraints, Shangyao Yan, Sin-Siang Wang, Chun-Yi Wang 2021 Department of Civil Engineering, National Central University, Taoyuan, Taiwan, R.O.C.

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 2021 Department of Systems and Naval Mechatronic Engineering, National Cheng Kung University, Tainan, Taiwan

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 2021 Department of Shipping and Transportation Management, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan, R.O.C.

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 2021 Department of Mechanical and Energy Engineering, National Chia-Yi University, Chia-Yi, Taiwan

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 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, Chun-Chieh Wang, Hsiao-Chuan Liu, Hsuan-Shih Lee, Cheng-Chi Chung 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, Tien-Hung Hou, Jen-Yi Chang, Chia-Cheng Tsai, Tai-Wen Hsu 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, Wen-Jer Chang, Kuang-Yow Lian, Cheung-Chieh Ku, Che-Lun Su 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, Tsung-Hsuan Hsieh, Shengzheng Wang, Huijia Gong, Wei Liu, Ning Xu 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, Wen-Cheng Lin, Hsin-Hung Cheng 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, Guozhi Bao, Peng Yang, Rui Da, Junxia Li, Guanghui Zhao, Ning Chen 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 …


Numerical And Field Study Of Tidal And Subtidal Dynamics In A Bar-Built Estuary: Barataria Bay, Gulf Of Mexico, Ali Reza Payandeh 2021 Louisiana State University

Numerical And Field Study Of Tidal And Subtidal Dynamics In A Bar-Built Estuary: Barataria Bay, Gulf Of Mexico, Ali Reza Payandeh

LSU Doctoral Dissertations

This study investigated tidal and subtidal dynamics of water level, currents, and suspended sediment concentration (SSC) in Barataria Bay, a shallow bar-built estuary of the Northern Gulf of Mexico. First, the local and remote wind forcing contribution on subtidal water level and current variability were examined using three different methods: (i) statistical analysis of observed data, (ii) an analytical model and (iii) a 2-D barotropic numerical model. Results suggested that the remote and local wind effects were equally important at the bay mouth, however local winds were the dominant forcing driver inside the bay. The amplitudes of subtidal fluctuations induced …


Physiological And Molecular Responses Of Eurythermal And Stenothermal Populations Of Zostera Marina L (Eelgrass) To Climate Change, Carmen C. Zayas-Santiago 2021 Old Dominion University

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 …


Deep Learning Approaches For Seagrass Detection In Multispectral Imagery, Kazi Aminul Islam 2021 Old Dominion University

Deep Learning Approaches For Seagrass Detection In Multispectral Imagery, Kazi Aminul Islam

Electrical & Computer Engineering Theses & Dissertations

Seagrass forms the basis for critically important marine ecosystems. Seagrass is an important factor to balance marine ecological systems, and it is of great interest to monitor its distribution in different parts of the world. Remote sensing imagery is considered as an effective data modality based on which seagrass monitoring and quantification can be performed remotely. Traditionally, researchers utilized multispectral satellite images to map seagrass manually. Automatic machine learning techniques, especially deep learning algorithms, recently achieved state-of-the-art performances in many computer vision applications. This dissertation presents a set of deep learning models for seagrass detection in multispectral satellite images. It …


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