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Phosphorus Speciation And Heavy Metal Levels In Ogun River Sediments At Different Anthropogenic Locations In Abeokuta, Ogun State, Olayinka Oluwafunmilayo Olasunbo, Opatoyinbo Oluwabamise Esther, Olujimi Olarenwaju Olusoji, Azeez Jamiu Oladipupo, Oyebanji Adedayo Olamide Jan 2023

Phosphorus Speciation And Heavy Metal Levels In Ogun River Sediments At Different Anthropogenic Locations In Abeokuta, Ogun State, Olayinka Oluwafunmilayo Olasunbo, Opatoyinbo Oluwabamise Esther, Olujimi Olarenwaju Olusoji, Azeez Jamiu Oladipupo, Oyebanji Adedayo Olamide

Applied Environmental Research

Phosphorus (P) is an essential nutrient for phytoplankton growth in water bodies and an important element in biochemical processes. Also, excessive P in river causes eutrophication which endangers aquatic organisms while sediment acts as sink for inorganic and organic pollutants and nutrients. To assess the availability of P and heavy metals (HMs) in Ogun River, surface sediment samples were collected at twelve anthropogenic sites for three months. The surface sediment samples were sequentially extracted to determine five phosphorus fractions [loosely-sorbed P (LS-P), iron-bound P (Fe-P), authigenic apatite, biogenic apatite and CaCO3-bound P (CFA-P), detrital apatite (Det-P) and other inorganic P …

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Removal Of Diclofenac In Wastewater By Activated Sludge In Batch And Moving-Bed Biofilm Reactor Experiments, Keletso Chakalisa, Piriyakorn Injai, Kullapa Chanawanno, Panaya Kotchaplai, Pumis Thuptimdang Jan 2023

Removal Of Diclofenac In Wastewater By Activated Sludge In Batch And Moving-Bed Biofilm Reactor Experiments, Keletso Chakalisa, Piriyakorn Injai, Kullapa Chanawanno, Panaya Kotchaplai, Pumis Thuptimdang

Applied Environmental Research

This study aimed to determine the diclofenac removal in wastewater by sludge taken from an operating wastewater treatment facility. Laboratory experiments were conducted in two parts: batch and moving-bed biofilm reactor (MBBR) experiments. Results from batch experiments showed that 0.1–2 mg L-1 of diclofenac could be removed more than 80% within 72 h, and the removal efficiency reduced to less than 60% for higher concentrations. The increase in the removal rate from 0.00058 to 0.16527 mg L-1 h-1 was observed when the initial diclofenac concentration increased from 0.1 to 10 mg L-1, respectively. The average first-order rate constants of 24-h …

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The Role Of Bacteria And Factors Affecting The Decomposition Of Pollutants In The Biofilter Reactor: A Review, Muliyadi Muliyadi, Purwanto Purwanto, Sri Sumiyati, Sudarno Sudarno, Budiyono Budiyono, Budi Warsito, Hadiyanto Hadiyanto Jan 2023

The Role Of Bacteria And Factors Affecting The Decomposition Of Pollutants In The Biofilter Reactor: A Review, Muliyadi Muliyadi, Purwanto Purwanto, Sri Sumiyati, Sudarno Sudarno, Budiyono Budiyono, Budi Warsito, Hadiyanto Hadiyanto

Applied Environmental Research

The findings showed that several types of bacteria can help biodegrade organic pollutants, such as Comamonadacea, which can biodegrade volatile fatty acids and aromatic compounds. Proteobacteria, Bacteroidetes, and Actinobacteria can biodegrade ammonium. Burkholderiales can biodegrade ferric ions and hydrogen. Comamonas testosteroni is able to biodegrade nitrates. Pseudomonas taiwanensis, Acinetobacter guillouiae, and Klebsiella pneumoniae can reduce copper, chromium and zinc levels. Azolla biomass reduces strontium. Rhodospirillum sp. can biodegrade cadmium, mercury, lead, and nickel. Gallionella ferruginea and Leptothrix sp. can biodegrade arsenic and manganese. Gracilaria sp. can biodegrade aluminum, chromium, and zinc. Desulfovibrio sp. can …

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Flying Blind: Exploring The Visual Cues Used By Helicopter Pilots In Degraded Visual Environments, Brandon Dreslin, Molly C. Mersinger, Shivani Patel, Alex Chaparro Jan 2023

Flying Blind: Exploring The Visual Cues Used By Helicopter Pilots In Degraded Visual Environments, Brandon Dreslin, Molly C. Mersinger, Shivani Patel, Alex Chaparro

Publications

Helicopter pilots rely on visual cues from the environment and instrument displays during critical phases of flight – particularly final approach and landing – to safely land. However, the specific visual cues pilots rely on and how they integrate those cues to make anticipatory inceptor inputs or corrections are not well understood. Importantly, those cues may be degraded under nighttime and brownout/whiteout conditions where the downwash of a helicopter’s rotors cause loose dirt/snow to be projected into the air, resulting in the obfuscation of the pilot’s vision outside the aircraft. The lack of visual cues in these conditions means that …

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A Framework For Assessing Environmental Incidents In Coastal Areas: A Case Study In The Southeastern Coastal Area Of Vietnam, Cuong Le Tan, Phuoc Nguyen Van, Quan Nguyen Hong, Loan Tran Thi Diem, Minh Tran Thanh Jan 2023

A Framework For Assessing Environmental Incidents In Coastal Areas: A Case Study In The Southeastern Coastal Area Of Vietnam, Cuong Le Tan, Phuoc Nguyen Van, Quan Nguyen Hong, Loan Tran Thi Diem, Minh Tran Thanh

Applied Environmental Research

As developing dynamic regions, coastal areas have a high potential for environmental incidents, especially chemical spills, which may permanently threaten livelihoods and coastal ecosystems. Establishing an appropriate methodological framework for assessing environmental incidents in coastal areas, ensuring increased predictability and minimising potential consequences is a trend of interest to scientists. In this study, the environmental risk assessment model was applied to develop a framework for assessing environmental incidents in coastal areas due to chemical spills from the mainland based on hazard, exposure and vulnerability factors (i.e., sensitivity and adaptability). Using the multiple criteria decision-making (MCDM) method approach, suitable criteria, their …

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Microplastic Contamination In The Coastal Environment: A Case Study From The Mae Klong River, Samut Songkhram, Pattraporn Chaisanguansuk, Suphak Ploenbuppa, Thitiphan Assawincharoenkij, Sumet Phantuwongraj, Akkaneewut Jiraphinyakul Jan 2023

Microplastic Contamination In The Coastal Environment: A Case Study From The Mae Klong River, Samut Songkhram, Pattraporn Chaisanguansuk, Suphak Ploenbuppa, Thitiphan Assawincharoenkij, Sumet Phantuwongraj, Akkaneewut Jiraphinyakul

Applied Environmental Research

To investigate the microplastic contamination in the coastal area in Samut Songkhram, we collected sediment samples from six locations in mangrove forests along the Mae Klong River estuary (MK) and the nearby Khlong Khon canal (KK). The microplastics were extracted by ZnCl2 density separation and subsequently H2O2 digestion. The microplastic abundance and physical properties, including their size, color, and shape, were determined under the binocular microscope. The selected microplastic samples were analyzed by µ-FTIR spectroscopy to identify their polymer types. Microplastic concentrations were c. 580 and 1690 items kg-1 d.w. in the samples from MK and KK. The lower microplastic …

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Assessment Of Heavy Metal Cd And Pb Concentrations And The Ecological Risk From Seawater, Sediments, And Perna Viridis In Semarang Bay, Indonesia, Max Rudolf Muskananfola, Agus Hartoko, Nurul Latifah Jan 2023

Assessment Of Heavy Metal Cd And Pb Concentrations And The Ecological Risk From Seawater, Sediments, And Perna Viridis In Semarang Bay, Indonesia, Max Rudolf Muskananfola, Agus Hartoko, Nurul Latifah

Applied Environmental Research

Semarang Bay is a multiple water source from some rivers located at the forefront of the most populated city in Central Java. These waters are polluted by wastes from various sources. Previous studies conducted were limited to specific areas and were mainly focused on one or two media only. This research aims to analyse the heavy metal Cd and Pb concentrations in seawater, sediments, and green mussels and the ecological risks. Field data were collected from 18 sites from three locations: Semarang, Demak and Kendal during the dry season of 2020. Environmental variables were measured in situ, and the heavy …

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Health Impacts From Pm2.5 Exposure Using Environmental Epidemiology And Health Risk Assessment: A Review, Thanakon Sukuman, Kayo Ueda, Sarunya Sujaritpong, Hirunwut Praekunatham, Kornwipa Punnasiri, Tuangsit Wimuktayon, Trakarn Prapaspongsa Jan 2023

Health Impacts From Pm2.5 Exposure Using Environmental Epidemiology And Health Risk Assessment: A Review, Thanakon Sukuman, Kayo Ueda, Sarunya Sujaritpong, Hirunwut Praekunatham, Kornwipa Punnasiri, Tuangsit Wimuktayon, Trakarn Prapaspongsa

Applied Environmental Research

Exposure to PM2.5 has been known to cause a variety of serious health consequences. Quantifying and investigating the health effects of PM2.5 pollution are imperative to understand and collect scientific evidence for supporting policies and associated actions. In this paper, we reviewed published environ-mental epidemiological studies and health risk assessments evaluating the health impacts of PM2.5 exposure in the PubMed database to identify the attributes of each method and aggregate the health impact results to perform analyses and summaries. Forty-two studies were identified after applying our search strategy, inclusion, and exclusion criteria. The epidemiological studies found an increased risk of …

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Banana Stem (Musa Balbisiana Colla) As Potential Biosorbent To Remove Methylene Blue Dye In Wastewater: Isotherm, Kinetic, Thermodynamic Studies And Its Application, Rahmiana Zein, Clalitya Akmal, Safni Safni, Syiffa Fauzia, Putri Ramadhani Jan 2023

Banana Stem (Musa Balbisiana Colla) As Potential Biosorbent To Remove Methylene Blue Dye In Wastewater: Isotherm, Kinetic, Thermodynamic Studies And Its Application, Rahmiana Zein, Clalitya Akmal, Safni Safni, Syiffa Fauzia, Putri Ramadhani

Applied Environmental Research

Textile industries discharge various waste including dye waste to the environment. Dye waste such as methylene blue taints both aquatic and land ecosystem. Thus, the recent study employs banana stem (Musa balbisiana Colla), as an economical and environmentally friendly biosorbent for methylene blue removal. The chemically activated banana stem indicates the significant methylene blue uptake at pH 5, initial concentration of 800 mg L-1, contact time of 60 min, temperature at 25 °C with adsorption capacity of 71.5470 mg g-1. The adsorption process follows the Langmuir isotherm model (R2 = 0.9965) and pseudo order model which involve monolayer …

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Potential Factors Of Landslide Recurrence In Uttaradit, Thailand: A Case Study In Laplae, Mueang Uttaradit, And Tha Pla Districts, Panithan Sawatdikomon, Watit Khokthong, Nipada Santha Jan 2023

Potential Factors Of Landslide Recurrence In Uttaradit, Thailand: A Case Study In Laplae, Mueang Uttaradit, And Tha Pla Districts, Panithan Sawatdikomon, Watit Khokthong, Nipada Santha

Applied Environmental Research

Laplae, Mueang Uttaradit, and Tha Pla district, Uttaradit province, Thailand are considered as high potential landslide areas. Still, this disaster is difficult to address because of complex factors controlling its occurrence. Therefore, the prediction of the potential landslide area using a landslide susceptibility map has been able to accomplish as a great strategy for the disaster.  A landslide susceptibility map was produced by the geographic information system (GIS) data. The methods were initially conducted by the selection of potential factors related to landslides, which were lithology, slope, aspect, plan curvature, profile curvature, distance to stream, land use, and rainfall. All …

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Application Of Fe3o4/Thiamine Magnetic Particles In The Removal Of Methylene Blue, Lan Tran-Nguyen, Suong Mai-Thi-Thu, Thanh-Ty Nguyen, Kim-Phung Ly, Luu-Ngoc-Hanh Cao, Tran Thi Bich Quyen, Shella Permatasari Santoso, Nguyen-Phuong-Dung Tran, Nguyen Minh Nhut Jan 2023

Application Of Fe3o4/Thiamine Magnetic Particles In The Removal Of Methylene Blue, Lan Tran-Nguyen, Suong Mai-Thi-Thu, Thanh-Ty Nguyen, Kim-Phung Ly, Luu-Ngoc-Hanh Cao, Tran Thi Bich Quyen, Shella Permatasari Santoso, Nguyen-Phuong-Dung Tran, Nguyen Minh Nhut

Applied Environmental Research

Fe3O4/thiamine particles were prepared in this work via precipitation method. The synthesis method is based on the principle of precipitation of Fe3O4 particles in the presence of thiamine coating agent. Also, the potential application of Fe3O4/ thiamine in the removal of methylene blue (MB) was investigated. Several factors that affect the synthesis of Fe3O4/thiamine such as base concentration, mass ratio of FeCl2 to thiamine, reaction temperature, and reaction time were determined. Optimal conditions for preparing Fe3O4/thiamine are NH4OH concentration = 10%, mass ratio of FeCl2:thiamine = 5:1 (g g-1), reaction temperature = 30 °C, reaction time = 120 min. The …

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The Effect Of Incubation Time And Drainage Ph On The Immobilization Of Copper In Post Coal Mine Soil Using Sumatera Brown Coal Char, Muhammad Haviz, Damris Muhammad, Maria Vabylita, Miftahul Djana, Rizka Mayasari, Ashruri -, Sandri Erfani, Yuli Darni, Opik Taufik Purwadi, Simparmin Ginting Jan 2023

The Effect Of Incubation Time And Drainage Ph On The Immobilization Of Copper In Post Coal Mine Soil Using Sumatera Brown Coal Char, Muhammad Haviz, Damris Muhammad, Maria Vabylita, Miftahul Djana, Rizka Mayasari, Ashruri -, Sandri Erfani, Yuli Darni, Opik Taufik Purwadi, Simparmin Ginting

Applied Environmental Research

Post coal mine (PCM) activities pose significant environmental challenges. Soils affected by PCM often exhibit increased acidity and elevated levels of heavy metals. In the case of Sungai Buluh PCM in the Jambi Province, Indonesia, copper (Cu) levels in the soil reach 94.79 mg kg-1, surpassing the Indonesian standard of 40 mg kg-1. Sumatera brown coal (SBC), typically is not considered as fuel due to its properties, offers a cost-effective solution for Cu immobilization in such soils. In this study, SBC was subjected to pyrolysis at 400°C for 1 h, sieved through a 10-mesh sieve, and characterized using SEM and …

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Distribution Of Exchangeable Magnesium In Lowland Rice-Cultivated Soils Of Sri Lanka As Affected By The Differences In Climate, Soil, And Water Source, Indeera Hetti Arachchige, Buddhi Marambe, Mohomad Nijamudeen, Harsha Kadupitiya, Dinaratne Sirisena, Rohana Chandrajith, Lalith Suriyagoda Jan 2023

Distribution Of Exchangeable Magnesium In Lowland Rice-Cultivated Soils Of Sri Lanka As Affected By The Differences In Climate, Soil, And Water Source, Indeera Hetti Arachchige, Buddhi Marambe, Mohomad Nijamudeen, Harsha Kadupitiya, Dinaratne Sirisena, Rohana Chandrajith, Lalith Suriyagoda

Applied Environmental Research

Magnesium (Mg) is an essential macronutrient for plants. Even though Sri Lankans consume rice as the staple food, the Mg status in Sri Lankan paddy soils as affected by its climate, soils, and water sources used are not well understood. This study was conducted to (i) determine the distribution of exchangeable Mg (ex-Mg) concentration, and (ii) examine the interactive effects of agro-climatic zones (ACZs), soil order, and water source in determining the ex-Mg concentra-tion in lowland paddy fields of Sri Lanka. A total of 9,038 soil samples representing six ACZs, six soil orders, and three water sources were collected using …

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The Effect Of Irrigation Techniques On Sustainable Water Management For Rice Cultivation System - A Review, Bittawat Wichaidist, Amornrat Intrman, Songsak Puttrawutichai, Chawakorn Rewtragulpaibul, Supatchaya Chuanpongpanich, Chaisri Suksaroj Jan 2023

The Effect Of Irrigation Techniques On Sustainable Water Management For Rice Cultivation System - A Review, Bittawat Wichaidist, Amornrat Intrman, Songsak Puttrawutichai, Chawakorn Rewtragulpaibul, Supatchaya Chuanpongpanich, Chaisri Suksaroj

Applied Environmental Research

Rice serves as a fundamental sustenance for approximately half of the global population, particularly in Asia. Nevertheless, the cultivation of rice demands a substantial water supply, and the challenges associated with water deficits have been exacerbated by irregular rainfall patterns induced by global warming. Consequently, there is a critical need to reassess irrigation techniques to effectively tackle these issues. In this comprehensive review, the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) method was employed to systematically explore literature on irrigation techniques aimed at fostering sustainable water management in rice cultivation systems. The primary components of the framework encompass …

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Context-Dependent Data-Envelopment-Analysis-Based Efficiency Evaluation Of Coastal Ports In China Based On Social Network Analysis, Yu Yu, Dai-Peng Ma, Guo-Ya Gan Jan 2023

Context-Dependent Data-Envelopment-Analysis-Based Efficiency Evaluation Of Coastal Ports In China Based On Social Network Analysis, Yu Yu, Dai-Peng Ma, Guo-Ya Gan

Journal of Marine Science and Technology–Taiwan

An emerging trend in performance evaluation is combining social network analysis methods with data envelopment analysis (DEA) models and using network centrality methods to distinguish DEA results. One study employed an input-oriented variable-returns-to-scale DEA model to address referent decision-making units and the corresponding lambda values to construct a network. This study referenced the literature and improved on the use of DEA weight sets to construct a network. We employed a context-dependent DEA model to delineate multiple effective frontier planes, aggregate the reference set relationships on each frontier plane to construct a network relationship matrix, and assess the influences of the …

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Research On Improving The Salary Structure Of Port State Control Officers In Taiwan, Te-Yi Chang, Wen-Chih Ho, Chung-Ping Liu, Yung-Wei Chen Jan 2023

Research On Improving The Salary Structure Of Port State Control Officers In Taiwan, Te-Yi Chang, Wen-Chih Ho, Chung-Ping Liu, Yung-Wei Chen

Journal of Marine Science and Technology–Taiwan

The implementation of port state control (PSC) has been challenging in Taiwan due to the lack of port state control officers (PSCOs), and foreign ships berthing at ports in Taiwan that cannot be effectively inspected. PSCOs of Taiwan are subordinate to the public service system and restrained by the number of personnel by the Executive Yuan. Compared with similar professions, their salaries are significantly different from those of the industry, making recruiting and retaining PSCOs a difficult task. Accordingly, this study improved the salary structure of PSCOs by conducting field interviews with existing PSCOs in Taiwan and applying the Fuzzy-AHP …

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Numerical Analysis Of Silencer With A Coiled Tube And Straight Perforated Tube Using Fem, Min-Chie Chiu, Ho-Chih Cheng Jan 2023

Numerical Analysis Of Silencer With A Coiled Tube And Straight Perforated Tube Using Fem, Min-Chie Chiu, Ho-Chih Cheng

Journal of Marine Science and Technology–Taiwan

Marine diesel engine is essential on a ship, but emits extremely loud noise harmful to human hearing. Therefore, it is mandatory to use silencers to reduce the venting noise of the marine diesel engine. An advanced silencer with a new acoustical element of a curved tube, along with perforated holes, is presented to suppress the noise wave. To predict the silencer's acoustical performance for high-order waves, a finite element model was built using COMSOL. The influence of the silencer's noise reduction ability was investigated by exploring sensitivity using acoustical simulations on COMSOL, regarding the silencer's geometric factors. The results proved …

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Abundance And Distribution Of Fish Larvae In The Central Coast Of The Algerian Sea, Etsouri Mohamed, Khames Ghollame Ellah Yacine, Seridji Rabea Jan 2023

Abundance And Distribution Of Fish Larvae In The Central Coast Of The Algerian Sea, Etsouri Mohamed, Khames Ghollame Ellah Yacine, Seridji Rabea

Journal of Marine Science and Technology–Taiwan

This study was conducted on a seasonal basis in five (5) stations along the central Algerian coast between April 2013 and April 2014 aboard professional fishing boats. Horizontal plankton tows with a WP2-type net were used to collect ichthyoplankton samples. At each station, temperature, salinity, and chlorophyll-a levels were measured. We identified the larvae of 18 species from 11 different families by sorting ichthyoplankton (Clupeidae, Engraulidae, Gobidae, Gonostomatidae, Mugilidae, Myctophidae, Scombridae, Sparidae, Carangidae, Labridae, Blennidae). Redundancy analysis (RDA) was used to determine the relationship between the abundance of harvested larvae and environmental variables. The results show a clear dominance of …

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Effects Of Direct Water Injection On The Nitrogen Oxide Emission Characteristics Of Marine Diesel Engines, Mahmoud Abdelnaser Saadeldin, M. M. Elgoharya, Maged Abdelnaby, Mohamed R. Shouman Jan 2023

Effects Of Direct Water Injection On The Nitrogen Oxide Emission Characteristics Of Marine Diesel Engines, Mahmoud Abdelnaser Saadeldin, M. M. Elgoharya, Maged Abdelnaby, Mohamed R. Shouman

Journal of Marine Science and Technology–Taiwan

This study examines the issue of diesel emissions from vehicles and vessels and their impact on environmental degradation with a focus on nitrogen oxide (NOx) emissions and their contribution to air pollution-related deaths worldwide. The novelty of this work is the use of computational fluid dynamics simulations to investigate the effectiveness of water addition for reducing NOx emissions. This study considers two methods of water addition, i.e., injection of water and air into a combustion chamber and mixing of water with fuel before injection. Adding water to air systems at 10% and 20% ratios reduces NOx emissions by 5% and …

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Predefined-Time Neural Sliding Mode Control Based Trajectory Tracking Of Autonomous Surface Vehicle, Han Xue, Shulin Li Jan 2023

Predefined-Time Neural Sliding Mode Control Based Trajectory Tracking Of Autonomous Surface Vehicle, Han Xue, Shulin Li

Journal of Marine Science and Technology–Taiwan

With the progress and development of modern industry, it is urgent to develop a more general and mature predefined time control theory system for uncertain nonlinear systems and apply it to practical engineering systems. Therefore, a novel predefined-time sliding mode control is designed to improve the slow convergence speed of asymptotically convergent controllers and finite-time convergent controllers affected by the initial state of the system. The proposed control approach is proved to converge from the initial value to the balance position using Jensen's inequality and Liapunov theorem. The proposed control method can deal with the ship motion system having six …

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Methanol As An Eco-Environmental Alternative Fuel For Ships: A Case Study, Samar K. Sallam, Mohamed M. Elgohary, Ibrahim S. Seddiek Jan 2023

Methanol As An Eco-Environmental Alternative Fuel For Ships: A Case Study, Samar K. Sallam, Mohamed M. Elgohary, Ibrahim S. Seddiek

Journal of Marine Science and Technology–Taiwan

Global emissions of Green House Gases and air pollutants are significantly influenced by shipping. Diesel fuel use for energy production is primarily responsible for these emissions. The substitution of traditional marine diesel oil with methanol as a marine fuel is recommended in this study. Moreover, the methanol-diesel dual-fuel engine's environmental and financial benefits are investigated numerically. A cruise passenger ship named Costa Toscana has been evaluated as a case study. Based on the data, the suggested dual-fuel engine reduces emissions of CO2, NOx, SOx, and PM by 25.7%, 38.46%, 45%, and 45%, respectively, with a cost-effectiveness of 286.5, 6645, 268403.4, …

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Collision Risk Prediction For Small Ships In South Korea Via Optimization Of Wireless Communication Period, So-Ra Kim, Myoung-Ki Lee, Sangwon Park, Dae-Won Kim, Young-Soo Park Jan 2023

Collision Risk Prediction For Small Ships In South Korea Via Optimization Of Wireless Communication Period, So-Ra Kim, Myoung-Ki Lee, Sangwon Park, Dae-Won Kim, Young-Soo Park

Journal of Marine Science and Technology–Taiwan

Since the emergence of COVID-19, there has been a global surge in demand for marine leisure activities. In Korea, the population using marine leisure has risen approximately 192% to 20,406 people, compared to 6,966 people in the year 2000, indicating a continuous growth over the past two decades.. Maritime transportation has become increasingly intricate worldwide due to the development of increasingly autonomous, larger, and faster ships. To effectively address potential hazards in such complex traffic environments, it is imperative to anticipate future scenarios and respond rapidly. However, small vessels account for the highest proportion of marine accidents, exhibit movements that …

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Path Planning Of Uav Navigation Mark Inspection Using A K-Means Clustering Aca, Jiaqi Li, Weifeng Li, Wenting Zhang Jan 2023

Path Planning Of Uav Navigation Mark Inspection Using A K-Means Clustering Aca, Jiaqi Li, Weifeng Li, Wenting Zhang

Journal of Marine Science and Technology–Taiwan

With increasing speeds and application of artificial intelligence in the shipping industry, unmanned aerial vehicle (UAV) technology has been applied to navigation mark inspections to improve the inspection efficiency and safety. Aimed at the UAV path planning problem of navigation mark inspection, this paper proposes an improved K-means clustering ant colony algorithm (KCACA) to design the shortest route for UAV navigation mark inspections. First, the K-means algorithm and the UAV maximum flight distance were used to cluster the navigation marks, which were then split into several secondary clusters. Each cluster was regarded as an independent traveling salesman problem to be …

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Coastal Traffic Safety Index Based On Marine Accident And Traffic Records, Joohwan Kim, Sang-Lok Yoo Jan 2023

Coastal Traffic Safety Index Based On Marine Accident And Traffic Records, Joohwan Kim, Sang-Lok Yoo

Journal of Marine Science and Technology–Taiwan

In this study, a comprehensive index for evaluating the degree of coastal traffic safety by simultaneously considering marine accident frequency, severity, and traffic volume was considered. To do so, the concept of Equivalent Property Damage Only (EPDO), which is widely used in the road transportation industry, was benchmarked to assess both frequency and severity of accidents. In addition, the total sailing distance of ships was chosen as a variable to explain traffic volume. Finally, a composite performance indicator called "M-EPDO per nautical mile" was built up, enabling the safety performance score for each type of ships in three criteria: on-board …

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Inventory Management In Supply Chains With Consideration Of Transportation And Green Technology Cost Under Progressive Carbon Taxation, Ming-Feng Yang, Min-Der Ko, Hung-Jen Tu, Mengru Tu, Jun-Yuan Kuo, Yen-Ting Chao, Shang-Wei Shih Jan 2023

Inventory Management In Supply Chains With Consideration Of Transportation And Green Technology Cost Under Progressive Carbon Taxation, Ming-Feng Yang, Min-Der Ko, Hung-Jen Tu, Mengru Tu, Jun-Yuan Kuo, Yen-Ting Chao, Shang-Wei Shih

Journal of Marine Science and Technology–Taiwan

Reducing carbon emissions is an important issue in the global supply chain. Governments have formulated different carbon policies to achieve carbon neutrality or emission reduction, in particular, the carbon tax as a policy provides greater certainty about the potential cost to emitters. The Taiwan government is expected to implement the carbon tax policy in 2024 and does not rule out the inclusion of a progressive mechanism which is more effective than a single carbon tax in curbing high carbon emissions Recent studies have also confirmed that a high level and complete carbon tax could encourage companies to invest in green …

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Geohash-Based Arrangement Of Live-Fire Exercise Areas Using Ais, Sang-Lok Yoo, Cho-Young Jung Jan 2023

Geohash-Based Arrangement Of Live-Fire Exercise Areas Using Ais, Sang-Lok Yoo, Cho-Young Jung

Journal of Marine Science and Technology–Taiwan

Live-fire exercise (LFX) areas at sea threaten the safety of ships, whereas, and indiscriminately abandoned unexploded bombs threaten the lives of fishermen. No statistical or scientific research has been conducted on the appropriate locations for LFX areas. Therefore, this study proposes a method for effectively arranging the LFX areas at sea that considers the safety of passing ships and national security. First, the proposed method classifies ship tracking data collected in the daytime based on the dawn and dusk times of the civil twilight phase. Second, the method uses a Geohash geocoding process to identify whether an LFX area coincides …

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Assessing Hierarchical Corporate Sustainability Transition Practices Under Uncertainty: An Approach In The Port And Shipping Industry In Southeast Asia, Mei-Train Yeh, Feng-Ming Tsai, Taufik Kurrahman Jan 2023

Assessing Hierarchical Corporate Sustainability Transition Practices Under Uncertainty: An Approach In The Port And Shipping Industry In Southeast Asia, Mei-Train Yeh, Feng-Ming Tsai, Taufik Kurrahman

Journal of Marine Science and Technology–Taiwan

The port and shipping industry in Southeast Asia has experienced significant development in response to the increasing demand for maritime logistics and transportation services. However, this expansion has resulted in notable social and environmental impacts. Consequently, it is imperative for both scholars and practitioners to comprehend the concept of corporate sustainability transition (CST), which entails the establishment of shipping operations that effectively balance environmental, social, and economic considerations. Additionally, technologies that are used to facilitate the transition process must be investigated. Several studies have been undertaken to ascertain the attributes pertaining to sustainability transition. Nevertheless, there has been a lack …

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Research On Risk Assessment Of Container Operation Process In Ports Considering Functional Areas, Chen-Yu Lin, Ming-Jiu Hwang, Tzu-Heng Yen Jan 2023

Research On Risk Assessment Of Container Operation Process In Ports Considering Functional Areas, Chen-Yu Lin, Ming-Jiu Hwang, Tzu-Heng Yen

Journal of Marine Science and Technology–Taiwan

The risk management of container ports has drawn significant attention recently in part because of recent high-profile accidents in global container ports and in part due to the increasing focus on port safety as a key element in sustainable maritime transportation. This research presented a novel, two-layer container port risk assessment model by partitioning the container port into four areas based on the process of container transportation: loading and unloading, in-port container transportation, storage, and gate areas. Failure mode and effects analysis (FMEA) and quantitative risk analysis modeling were combined for each part of the process to evaluate the risk …

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Artificial Intelligence In Prediction Of The Remaining Useful Life Of Wind Turbine Shaft Bearings, Jinsiang Shaw, B.J. Wu Jan 2023

Artificial Intelligence In Prediction Of The Remaining Useful Life Of Wind Turbine Shaft Bearings, Jinsiang Shaw, B.J. Wu

Journal of Marine Science and Technology–Taiwan

Long-term periodic rotation and unstable load changes in wind turbines can cause unexpected damage to high-speed shaft bearings (HSSBs). In this study, after preprocessing of the HSSB vibration signal, four different models for predicting bearing degradation in terms of remaining useful life (RUL) in days were investigated: support vector regression (SVR), convolutional neural networks (CNN), long short-term memory (LSTM), and CNN-LSTM. The experimental results revealed that the CNN achieved the best mean absolute error (MAE), at 0.44 days, based on frequency response plot using the fast Fourier transform (FFT), while that of the CNN-LSTM model predicted using the amplitude profile …

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Impact Of Multiple Water Temperature Structures On The Behavioral Pattern Of Chum Salmon (Oncorhynchus Keta) On The Coast Of The Shiretoko Peninsula, Xinyi Li, Hiroshi Yamaguchi, Hokuto Shirakawa, Kenji Minami, Nobuhiko Sato, Yanhui Zhu, Yasuyuki Miyakoshi, Kazushi Miyashita Jan 2023

Impact Of Multiple Water Temperature Structures On The Behavioral Pattern Of Chum Salmon (Oncorhynchus Keta) On The Coast Of The Shiretoko Peninsula, Xinyi Li, Hiroshi Yamaguchi, Hokuto Shirakawa, Kenji Minami, Nobuhiko Sato, Yanhui Zhu, Yasuyuki Miyakoshi, Kazushi Miyashita

Journal of Marine Science and Technology–Taiwan

During the migration of chum salmon (Oncorhynchus keta) towards the Shiretoko Peninsula in Hokkaido, Japan, the convergence of coastal currents results in the formation of intricate water temperature structures. However, the impact of this phenomenon on the behavioral tendencies of chum salmon remains largely unexplored. In 2012 and 2013, we conducted a study to document the vertical water temperature profiles and uninterrupted swimming patterns of homing chum salmon in the coastal waters surrounding the Shiretoko Peninsula. The results indicated that chum salmon exhibited a preference for avoiding thermoclines characterized by rapidly decreasing water temperatures. They were predominantly observed swimming either …

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