Oceanography and Atmospheric Sciences and Meteorology Commons^™

Numerical Study On The Aerodynamic Performance Of Four Flettner Rotors By Varying Distance And Spin Ratio, Janghoon Seo, Dong-Woo Park

Journal of Marine Science and Technology–Taiwan

The Flettner rotor is a wind-assisted propulsion system applied in eco-friendly ship to reduce greenhouse gas emissions. As the requirements of international regulations on greenhouse gas emissions become increasingly strict, multiple Flettner rotors are being applied, necessitating the evaluation of their performance with varying design parameters. The present study focuses on the aerodynamic performances of four Flettner rotors with variable design parameters of distance and spin ratio. Distances and spin ratios, including relative spin ratios, are considered. The drag and lift coefficients and lift-to-drag ratio of Flettner rotors are determined using Computational Fluid Dynamics (CFD), and the associated flow fields …

Underwater Image Enhancement Algorithm For Dual Color Spaces, Xingsheng Shen, Yalin Song, Shichang Li, Xiaoshu Hu

Journal of Marine Science and Technology–Taiwan

Targeting issues related to low contrast, blurring, and loss of detail prevalent in underwater image enhancement algorithms, we propose a dual-color space multiscale residual network (DMR-SCNet) based on SCNet. First, we introduce the HSV color space feature extraction module, which aims to optimize the color representation and saturation of underwater images. Subsequently, we propose the RGB color space denoising module, which focuses on repairing the content and structure of underwater images to enhance their clarity and visual quality. Finally, by designing the residual attention (RAB) module, we aim to further refine the detailed representation and feature extraction of underwater images. …

A Novel Identity Authentication Mechanism For Unmanned Maritime Vessels Communication Based On Mitre Att&Ck Framework, Junxian He, Shih-Hao Chang

Journal of Marine Science and Technology–Taiwan

With the development of the smart shipping industry, unmanned vessel technology is rapidly evolving, accompanied by a demand for robust Internet of Things (IoT) communication security practices. Key communication technologies for the operation of unmanned vessels include external vessel communication. One crucial aspect is the verification of the identities of the parties involved in these communication systems, as this ensures secure and trusted interactions between unmanned vessels and port management authorities. Identity authentication plays a vital role in ensuring the secure communication of unmanned vessels.This paper aims to analyze potential risks related to identity authentication technology in unmanned vessel communication …

Corrigendum To “Applicability Of Reducing Valve Timing Overlap For Diesel Engines Under High Exhaust Back Pressure”

Journal of Marine Science and Technology–Taiwan

No abstract provided.

Distribution And Population Structure Of Corallivorous Drupella Snails In The Coral Reefs Of Kenting In Taiwan, Chih-Jui Tan, Dun-Ru Kang, Li-Lian Liu

Journal of Marine Science and Technology–Taiwan

The corallivorous Drupella snails are common predators of living hard corals in the Indo-Pacific Ocean, and they can significantly threaten coral reef ecosystems when outbreaks occur. In Taiwan, a Drupella outbreak, which resulted in the dramatic decline of Acropora and Montipora corals, was reported in Penghu in 2002 – 2009. However, the Drupella species involved was not identified, and no further research has been conducted. To obtain current knowledge on the predation pressure of corallivorous snails on hard corals, we investigated benthic communities and the distribution and population structure of Drupella snails in the coral reefs of Kenting, Taiwan. The …

Evaluating The Connectivity Reliability Of The Seaborne Transportation Network Using Uncertainty Theory, Tianshou Liu, Haiyang Bian, Lin Feng, Chenyang Fan, Chaojun Ding, Grifoll Manel, Hongxiang Feng

Journal of Marine Science and Technology–Taiwan

The shipping network serves as the backbone of international trade. However, due to unstable geopolitical conditions, unexpected events have occurred frequently in recent years that have impacted the global shipping supply chain, and this has placed enormous pressure and had adverse effects on seaborne transportation. To measure the reliability of the global shipping network under unexpected events, we abstract the global shipping network into a small world network using uncertainty theory. A method is proposed for selecting (i) the optimal reliable path and (ii) the optimal reliable path with a maximum measurement under different confidence intervals. Our approach is then …

Mechanical Property Analysis And Three-Dimensional Reverse Reconstruction Based On Corrosion Pit Characteristics Of Strong Corrosion Steel Plate, Qiujun Ning, Xiaosong Lu, Jiawei Lu

Journal of Marine Science and Technology–Taiwan

To investigate the strong corrosion effect of 36% industrial hydrochloric acid on Q370 steel for bridges at room temperature. The surface morphology variations of the Q370 steel for bridges with corrosion time were measured and analyzed using a three-dimensional non-contact scanning profilometer. Subsequently, the standard monotonic tensile test was carried out to obtain the load-displacement curve and analyze the mechanical properties of the heavily corroded steel. Moreover, the constitutive model parameters of the heavily corroded steel were optimized. Furthermore, the heavily corroded steel model base on the actual corroded surface morphology was established, employing three-dimensional reverse reconstruction technology and finite …

Sea Ice Identification And Risk Assessment For Navigation In Ice Regions Based On Shipboard Camera Images, Tsung-Hsuan Hsieh, Xuan Lu, Shengzheng Wang, Wei Liu, Jianan Luo

Journal of Marine Science and Technology–Taiwan

In order to guarantee the safe navigation of vessels in icy regions and effectively capture sea ice risk information surrounding ships, this study introduces a sea ice identification and risk assessment process utilizing shipboard camera images. Firstly, based on the distribution characteristics of sea area, a hierarchical region segmentation algorithm is proposed to precisely remove interference factors and extract the region of interest. Then, a multivariate K-means clustering algorithm is proposed to classify sea ice classes based on various characteristics, including spatial similarity, sea ice area, sea ice thickness, gray scale, and other multivariate information. Finally, a method for small …

Optimization On Container Drayage Scheduling In Stochastic Time-Dependent Network, Qi Xu, Jie Huang, Xingyue Chen, Rui Cheng, Xiangyu Yin, Zhongzhen Yang

Journal of Marine Science and Technology–Taiwan

To ensure a reliable operation of container drayage transport system, this paper investigates the drayage scheduling problem in a stochastic time-dependent network. Based on the theory of the robust optimization, a mathematical model considering the attributes of “synchronized operation of multi machines” is built with the aim of minimization of the schedule delay in the whole system. A Simulated Annealing algorithm with Embedded Heuristics (SAEH) is designed for model solution. Comparisons between the results from the robust optimization and traditional expected value approach, and the results from the SAEH and CPLEX are conducted. Based on that, the effectiveness of our …

Offshore Vertical Axis Wind-Photovoltaic Power Plants: Development And Case Study, Victor V. Cheboxarov, Pavel N. Kuznetsov, Shun-Han Yang, Shiu-Wu Chau

Journal of Marine Science and Technology–Taiwan

This paper examines the potential for the development and implementation of hybrid wind-solar power plants utilizing large-scale offshore vertical-axis wind turbines. The proposed solution aims to increase energy production and reliability through the integration of photovoltaic modules directly into the wind turbine structure. Schematics of photovoltaic modules on the upper annular surface of the respective wind turbine are considered. The operation of the hybrid power plant is described. Equations to estimate the power characteristics of the plant are given. The case study analyzes the potential energy production of a hybrid marine power plant with a diameter of 200 m at …

Harvest By Autoflocculation, Biomass, And Carotenoid Production In Sequential Batch Culture Of Haematococcus Pluvialis Under High Ionic Strength And Macroelements Content, J. Galán-González, I. Quintero-Zapata, M Elías-Santos, L.J. Galán-Wong, U.J. López-Chuken, C Guajardo-Barbosa, J.C Beltrán-Rocha

Journal of Marine Science and Technology–Taiwan

Haematococcus pluvialis is a microalga with significant potential due to its capacity to produce carotenoids with antioxidant and nutraceutical benefits. However, the cost of harvesting this microalga, constituting over 30% of total expenses in large-scale production, is a major concern. Efficient flocculation, aiding in cell separation from the culture medium, is crucial to address this issue. The study contrasted Bold’s Basal Medium (BBM) with Lopez-Chuken & Young nutrient solution (LC-Y). The heightened salt content in LC-Y plays a crucial role in fostering saline stress, which is essential for evaluating H. pluvialis flocculation, biomass yield, and carotenoid production. To assess stability …

Research Progress On Ship Trajectory Prediction In Marine Transportation, Xiangen Bai, Kai Ye, Xiaofeng Xu

Journal of Marine Science and Technology–Taiwan

The prediction of ship navigation trajectories is crucial for ensuring maritime navigation safety and forecasting risk. In recent years, extensive research has been conducted on the prediction of ship navigation trajectories at home and abroad, and some results have been achieved. At present, most research on ship navigation trajectory prediction relies heavily on automatic identification system (AIS) data and the historical trajectories of ships. This study first reviews the research background and current situation of ship navigation trajectory prediction. Second, it provides an overview of ship navigation trajectory prediction, with an emphasis on sorting out and elaborating on artificial intelligence …

Numerical Investigations On Particle Collection And Discharge Of Rounded Rectangle Aquaculture Tank In Dual-Diagonal-Inlet Layout, Xiaozhong Ren, Shupeng Du, Hangfei Liu, Xianying Shi, Meng Li, Xian Wang, Suping Liu

Journal of Marine Science and Technology–Taiwan

To improve the space utilization rate of aquaculture tanks in aquaculture facilities and investigate the effect of the length-width ratio parameter (abbr. L/W, with L being the length of the tank and W being its width) on the particle collection and discharge characteristics of the rounded rectangle aquaculture tank with diagonal double inlet pipes. The study simulates the particle discharge procedure of the tank using a solidliquid two-phase numerical model (discrete phase model and RNG k-ε turbulence model adopted). The validity of the numerical model was confirmed through physical experiments. The simulation results for two jet condition indicate that when …

2024 January - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.

Exploring The Atmospheric And Weather Conditions For Hoar Frost Formation At Or Tambo International Airport: A Case Study Of Ground Aircraft Icing Events For The Period 2017-2023., Thabisile P Z Ntleko Ms, Xolani Matlou Mr

International Journal of Aviation, Aeronautics, and Aerospace

Ground aircraft icing has an adverse effect on the aerodynamic performance of aircrafts as well as the efficient operations of airlines and airports. The South African Weather Service (SAWS) Aviation Weather Centre (AWC) issues forecasts and warnings for the aviation community, which include aerodrome warnings for hoar frost accumulation. The infrequent and notable temporal occurrence of this weather phenomena renders it a rare aviation hazard to warn for, therefore understanding the weather and atmospheric conditions conducive for its formation is important for accurate forecasting. This study analyses 28 incidents of ground aircraft icing events at OR Tambo International Airport, South …

The Impact Of Thunderstorms On Take-Off Data In South Africa, Quinton Jacobs Mr.

International Journal of Aviation, Aeronautics, and Aerospace

Aviation and meteorology are entwined disciplines, as aviation occurs in the atmosphere. Prevailing weather conditions at take-off are of utmost importance to aviation. This determines the payload of the aircraft and runway in use. Forecast verification is essential to aviation as it determines the quality of the forecasting products. The tolerances for take-off data are stringent and slightly relaxed tolerances are used in South Africa by mutual agreement.

There are six aerodromes in South Africa where Take-off Data are produced, in varying climatic conditions as South Africa is in both the tropics and midlatitudes. Thunderstorms are a common occurrence over …

A Comparison Of Arctic And Atlantic Basin Cyclone Predictability From A Climatology And Case Study Perspective, Peyton Capute

Electronic Theses & Dissertations (2024 - present)

Arctic cyclones (ACs) can transport warm, moist air into the Arctic region, which combined with strong winds may lead to rapid declines in sea ice during the summer. As a consequence, accurate sea ice predictions during the summer may rely on being able to predict cyclone-related wind speed and direction, which critically depends on the cyclone track and intensity. Despite this, there are relatively few studies that have documented the predictability of ACs during the summer, beyond a few case studies. In addition, there has been no extensive comparison of whether these cyclones are more or less predictable relative to …

Complex Dynamics Of Coral Gene Expression Responses To Low Ph Across Species, Veronica Z. Radice, Ana Martinez, Adina Paytan, Donald C. Potts, Daniel J. Barshis

Biological Sciences Faculty Publications

Coral capacity to tolerate low pH affects coral community composition and, ultimately, reef ecosystem function. Low pH submarine discharges (‘Ojo’; Yucatán, México) represent a natural laboratory to study plasticity and acclimatization to low pH in relation to ocean acidification. A previous >2‐year coral transplant experiment to ambient and low pH common garden sites revealed differential survivorship across species and sites, providing a framework to compare mechanistic responses to differential pH exposures. Here, we examined gene expression responses of transplants of three species of reef‐building corals (Porites astreoides, Porites porites and Siderastrea siderea) and their algal endosymbiont communities …

Half Of Atlantic Reef-Building Corals At Elevated Risk Of Extinction Due To Climate Change And Other Threats, Luis Gutierrez, Beth Polidoro, David Obura, Francoise Cabada-Blanco, Christi Linardich, Emma Pettersson, Paul Pearce-Kelly, Krista Kemppinen, Juan Jose Alvarado, Lorenzo Alvarez-Filip, Anastazia Banaszak, Pilar Casado De Amezua, James Crabbe, Aldo Croquer, Joshua Feingold, Elizabeth Goergen, Stefano Goffredo, Bert Hoeksema, Danwei Huang, Emma Kennedy, Diego Kersting, Marcelo Kitahara, Petar Kružić, Margaret Miller, Flavia Nunes, Juan Pablo Quimbayo, Andrea Rivera-Sosa, Rosa Rodríguez-Martínez, Nadia Santodomingo, Michael Sweet, Mark Vermeij, Estrella Villamizar, Greta Aeby, Khatija Alliji, Daniel Bayley, Elena Couce, Benjamin Cowburn, C. Isabel Nuñez Lendo, Sean Porter, Kaveh Samimi-Namin, Tom Shlesinger, Bryan Wilson

Biological Sciences Faculty Publications

Atlantic reef-building corals and coral reefs continue to experience extensive decline due to increased stressors related to climate change, disease, pollution, and numerous anthropogenic threats. To understand the impact of ocean warming and reef loss on the estimated extinction risk of shallow water Atlantic reef-building scleractinians and milleporids, all 85 valid species were reassessed under the IUCN Red List Categories and Criteria, updating the previous Red List assessment of Atlantic corals published in 2008. For the present assessment, individual species declines were estimated based on the modeled coral cover loss (1989–2019) and projected onset of annual severe bleaching events (2020–2050) …

Analyzing The Correlation Between Surface Elevation And Seasonal And Diurnal Surface Temperature Cycles On Mars, Emily A. Dolan

Electronic Theses & Dissertations (2024 - present)

Recent technologies such as the Mars Climate Sounder, the Mars Orbiter Laser Altimeter, and the Curiosity rover have allowed scientists to examine Mars’ surface, climate, and atmospheric dynamics. Surface temperature data from the Mars Climate Sounder (MCS) were collected and seasonal and diurnal cycles were extracted via Fourier regression analysis into a 1° latitude longitude grid. Diurnal cycles were shown to move from west to east across the surface throughout the day, while seasonal cycles moved from north to south. Two key diurnal portions, one in the early morning, and another in the late afternoon, were chosen due to their …