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Full-Text Articles in Engineering

An Optimal Schedule Recovery Model For Transportation Carriers Under Uncertain Typhoon Disruption Periods, Yi-Chun Chen, Shangyao Yan Sep 2024

An Optimal Schedule Recovery Model For Transportation Carriers Under Uncertain Typhoon Disruption Periods, Yi-Chun Chen, Shangyao Yan

Journal of Marine Science and Technology

Due to the unsettled weather conditions caused by typhoons, it is not possible to forecast the time when a typhoon will arrive or depart accurately. The uncertainty regarding the duration of typhoon disruptions makes it challenging for transportation carriers to efficiently adjust their schedules. In this study, to deal with the problem of airline fleet rerouting, flight rescheduling, and passenger reassignment for uncertain disruption periods caused by a typhoon, we utilize network flow techniques with the concept of probability to construct a stochastic model for minimizing the total operating costs. A heuristic algorithm based on the divide-and-conquer technique is adopted …


Enhancing Dtc Control Of Im Using Fuzzy Logic And Three-Level Inverter: A Comparative Study, Siham Mencou, Majid Benyakhlef, Elbachir Tazi Sep 2024

Enhancing Dtc Control Of Im Using Fuzzy Logic And Three-Level Inverter: A Comparative Study, Siham Mencou, Majid Benyakhlef, Elbachir Tazi

Turkish Journal of Electrical Engineering and Computer Sciences

Direct torque control is the most appropriate strategy for induction motor drive systems, due to its considerable ability to reduce the impact of of machine parameter variations, while offering fast dynamic response and simplified control implementation. However, persistent problems associated with high torque ripple and variable switching frequencies prevent its widespread adoption. To overcome these limitations, several techniques have been developed, in particular the use of multi-level inverters and fuzzy logic algorithms. This article proposes an in-depth evaluation of these techniques in a MATALB/Simulink environment, under various operational conditions. The main objective is to provide a detailed performance analysis of …


Power Quality Enhancement In Hybrid Pv-Bes System Based On Ann-Mppt, Heli̇n Bozkurt, Özgür Çeli̇k, Ahmet Teke Sep 2024

Power Quality Enhancement In Hybrid Pv-Bes System Based On Ann-Mppt, Heli̇n Bozkurt, Özgür Çeli̇k, Ahmet Teke

Turkish Journal of Electrical Engineering and Computer Sciences

Battery energy systems (BESs) assisted photovoltaic (PV) plants are among the popular hybrid power systems in terms of energy efficiency, energy management, uninterrupted power supply, grid-connected and off-grid availability. The primary objective of this study is to enhance the power quality of a grid-tied PV-BES hybrid system by developing an operation strategy based on Artificial Neural Network (ANN) based maximum power point tracking (MPPT) method. A test system comprising a 10-kWh BES and a 12.4 kW PV plant is structured and simulated on the MATLAB/Simulink platform. The hybrid system is validated with three different cases: constant radiation, rapid changing radiation, …


Finger Movement Recognition Using Machine Learning Algorithms With Tree-Seed Algorithm, Muhammed Sami̇ Karakul, Ahmet Gökçen Sep 2024

Finger Movement Recognition Using Machine Learning Algorithms With Tree-Seed Algorithm, Muhammed Sami̇ Karakul, Ahmet Gökçen

Turkish Journal of Electrical Engineering and Computer Sciences

Electromyography (EMG) signals have been used to recognize various actions of hand movements, finger movements, and hand gestures. This paper aims to improve the classification accuracy of EMG signals while decreasing the number of features using the Tree-Seed Algorithm. The dataset containing EMG signals utilized in this investigation is derived from a publicly accessible source. The rationale for selecting the Tree-Seed Algorithm centers on its ability to enhance classification accuracy while minimizing the dimensionality of feature sets. The object function and Tree-Seed Algorithm's nature avoids the results to have low accuracy with fewer features. The aim is not just to …


Mention Detection In Turkish Coreference Resolution, Şeni̇z Demi̇r, Hani̇fi̇ İbrahi̇m Akdağ Sep 2024

Mention Detection In Turkish Coreference Resolution, Şeni̇z Demi̇r, Hani̇fi̇ İbrahi̇m Akdağ

Turkish Journal of Electrical Engineering and Computer Sciences

A crucial step in understanding natural language is detecting mentions that refer to real-world entities in a text and correctly identifying their boundaries. Mention detection is commonly considered a preprocessing step in coreference resolution which is shown to be helpful in several language processing applications such as machine translation and text summarization. Despite recent efforts on Turkish coreference resolution, no standalone neural solution to mention detection has been proposed yet. In this article, we present two models designed for detecting Turkish mentions by using feed-forward neural networks. Both models extract all spans up to a fixed length from input text …


A Single Operational Amplifier-Based Grounded Meminductor Mutators And Their Applications, Shalini Gupta, Kunwar Singh, Shireesh Kumar Rai Sep 2024

A Single Operational Amplifier-Based Grounded Meminductor Mutators And Their Applications, Shalini Gupta, Kunwar Singh, Shireesh Kumar Rai

Turkish Journal of Electrical Engineering and Computer Sciences

In this work, three simple configurations of meminductor mutator are presented. The first two configurations of meminductor mutator have been implemented utilizing one CMOS-based operational amplifier, one memristor, one capacitor, and five resistors, while the third configuration of meminductor mutator is implemented utilizing one CMOS based operational amplifier, two memristors, one capacitor, and four resistors. The implementation and simulation of the proposed configurations are done by using LTspice tool. The viability of the proposed circuits is demonstrated by utilizing TSMC 180 nm CMOS technology parameters. The proposed circuits of the meminductor have a simple structure in contrast to many of …


Prediction Of Mooring System Characteristics Of The Floating Barge Using Deep Neural Networks, Janghoon Seo, Dong-Woo Park Sep 2024

Prediction Of Mooring System Characteristics Of The Floating Barge Using Deep Neural Networks, Janghoon Seo, Dong-Woo Park

Journal of Marine Science and Technology

The present study establishes deep learning models to predict the tensions and inclinations of mooring lines of a floating barge and verifies applicability of these models. Hydrodynamic and mooring analyses are conducted on the dataset used for the deep learning models. Three types of neural network models include a deep neural network (DNN) with input data representing the six degrees of freedom motions of a floating barge, convolutional neural network (CNN) with input images of the floating barge and mooring lines on a horizontal plane, and hybrid neural network (HNN) that consolidates the characteristics of DNN and CNN models. The …


Method Of Selecting The Optimal Variant Of Mine Closure With The Possibility Of Capturing Methane From Underground Excavations, Marian Turek, Małgorzata Magdziarczyk Sep 2024

Method Of Selecting The Optimal Variant Of Mine Closure With The Possibility Of Capturing Methane From Underground Excavations, Marian Turek, Małgorzata Magdziarczyk

Journal of Sustainable Mining

The article presents a method of selecting the optimal option for the closure of a coal mine, from which it is planned to capture the methane remaining in the goaf and deposit it for many years for its economic use. Using the example of several options for the closure of one of the mines, for which the evaluation criteria have been defined, and the weights of their relevance have been determined, it is described how to create a special algorithm for the selection of the optimal option.


Application Of Haines And Terbrugge Chart For Suitable Slope Angles – A Case Study Of Artisanal And Small-Scale Mining, Carol Mgiba, Steven Rupprecht Sep 2024

Application Of Haines And Terbrugge Chart For Suitable Slope Angles – A Case Study Of Artisanal And Small-Scale Mining, Carol Mgiba, Steven Rupprecht

Journal of Sustainable Mining

Significant hazards in Artisanal and small-scale mining (ASM) are rock failure and slope collapse caused by overly steep pit walls, poor mine design and water pressure. There is a lack of expertise and capital in ASM. Providing a simple and cost-effective slope stability analysis and designing systems that can mitigate the risk of slope collapse is essential. This article aims to assess whether stability charts and estimations can be used to establish suitable slope angles to mitigate the overwhelming cases of slope collapse in ASM. The Bieniawski’s Rock Mass Rating system and Heins and Terbrugge stability chart were used to …


Integrated Environmental Vulnerability Assessment And Adaptation Strategies For Coastal Areas Under Sustainable Development, Lien-Kwei Chien, Yu-Chi Li, Chia-Feng Hsu Sep 2024

Integrated Environmental Vulnerability Assessment And Adaptation Strategies For Coastal Areas Under Sustainable Development, Lien-Kwei Chien, Yu-Chi Li, Chia-Feng Hsu

Journal of Marine Science and Technology

This research focuses on the holistic management and environmental vulnerability of coastal areas in Taiwan within the framework of sustainable development. With economic and social growth gravitating towards coastal regions, the strain on the natural environment is increasing. Therefore, discovering a balance between economic progress and environmental conservation is paramount. To decipher the vulnerability of Taiwan's coastal zones, this study first defines ‘Integrated Environmental Vulnerability of Coastal Areas.’Key vulnerability factors were identified across environmental, social, and economic dimensions. Seven core determinants were determined using the Fuzzy Delphi method: biodiversity, coastal erosion, water pollution, population density, population aging, land utilization, and …


Evalution Of The Ability To Infer Tilt Angle And Size Distributions Of Fish Using A Broadband Scientific Echosounder Based On Simulation, Jing Liu Sep 2024

Evalution Of The Ability To Infer Tilt Angle And Size Distributions Of Fish Using A Broadband Scientific Echosounder Based On Simulation, Jing Liu

Journal of Marine Science and Technology

The biological information, such as species, size, and tilt angle, is crucial for converting the echo data into biomass information in acoustic surveys. Typically, the information can be obtained through trawl net sampling or underwater camera observations. However, both methods have some limitations. To overcome these limitations, scientists have utilized inversion methods with multi-frequency and broadband echosounders to derive biological information about fish, plankton, and krill. However, evaluating the reliability and accuracy of these inversion methods has been challenging due to the difficulty in obtaining accurate biological information. In this study, a numerical simulation method was used to generate fish …


Performance Studies Of An Axial Flow Waterjet Pump Using An Unsteady Reynolds-Averaged Navier-Stokes Model, Stephen E. Monroe, Junfeng Wang, Chunlei Liang Sep 2024

Performance Studies Of An Axial Flow Waterjet Pump Using An Unsteady Reynolds-Averaged Navier-Stokes Model, Stephen E. Monroe, Junfeng Wang, Chunlei Liang

Northeast Journal of Complex Systems (NEJCS)

In this study, an Unsteady Reynolds-Averaged Navier-Stokes (URANS) model is demonstrated its suitability for studying the flow and performance of open marine propellers and waterjet pumps. First, the accuracy of the URANS model is validated by studying turbulent flow past counter-rotating propellers (CRPs). Specifically, experimental data from Miller (1976) is employed for comparison against the URANS results. Subsequently, URANS is used to study the flow and performance of an Office of Naval Research (ONR) axial flow waterjet pump (AxWJ-2). Due to the large number of degrees of freedom for both simulations, parallel computations over 80 cores are performed. For the …


A Marine Knowledge System For Ocean Affairs: Integrating Data, Evaluating Usage, And Enabling Sustainable Marine Management, Yu-Jen Pan Sep 2024

A Marine Knowledge System For Ocean Affairs: Integrating Data, Evaluating Usage, And Enabling Sustainable Marine Management, Yu-Jen Pan

Journal of Marine Science and Technology

This study presents the evolution and assessment of the Marine Knowledge Education System (MKES), designed to improve user acceptance among students in professional marine science courses in Taiwan. The MKES leverages real-world maritime cases from the General Coast Guard Administration and is built upon existing technologies like cloud services, social networks, and data analysis tools. The technology acceptance model (TAM) provides the theoretical underpinning for the assessment of user confidence. Data was collected from 190 participants through purposive sampling. Path analysis confirmed all hypothesized relationships within the TAM with statistical significance (p < 0.001). Additionally, paired-sample t-tests revealed a significant increase in student acceptance of the MKES after integrating it into the marine science curriculum. These findings underscore the capacity of the MKES as a digital learning tool to enrich course pedagogy and improve student learning outcomes, thereby offering valuable support in advancing the education of professional marine managers.


Utilization Of Solar And Wind Power-Generation Systems In The Mining Industry: Recent Trends And Future Prospects, Elaheh Mohammadi Valikandi, Yosoon Choi Aug 2024

Utilization Of Solar And Wind Power-Generation Systems In The Mining Industry: Recent Trends And Future Prospects, Elaheh Mohammadi Valikandi, Yosoon Choi

Journal of Sustainable Mining

In recent years, the mining industry has faced many challenges, such as rising demand, fluctuating energy prices, increasing energy consumption due to declining ore grades, and environmental concerns. According to the Paris Agreement, countries worldwide must focus on decarbonizing their economies to mitigate the global average surface temperature growth. This paper reviews how renewable energy, specifically photovoltaic and wind power systems, can be used to tackle some of these challenges. Operating mines globally, like the South Deep gold mine in South Africa and the MA'ADEN Alumina Refinery in Saudi Arabia, and abandoned mines, such as former coal mines in the …


A Step By Step Shoreline Attribute Analysis For Selected Waterbodies In The Gulf Of Mexico To Promote The Use Of Living Shorelines, Christoper Boyd, Xutong Niu, Taylor R. Horn Aug 2024

A Step By Step Shoreline Attribute Analysis For Selected Waterbodies In The Gulf Of Mexico To Promote The Use Of Living Shorelines, Christoper Boyd, Xutong Niu, Taylor R. Horn

The Journal of Extension

Living Shorelines are being promoted by coastal extension professionals as a more resilient nature-based solution to control shoreline erosion. The Virginia Institute of Marine Sciences Living Shorelines Suitability Model was run in selected waterbodies within the Gulf of Mexico.

The locations of the selected water bodies, coastal data sets used, and shoreline protection recommendations generated by the Model are presented. A step-by-step statistical analysis conducted through ArcGIS Pro from these selected coastal shorelines will illustrate how extension professionals with novice GIS experience can use the model output to promote living shorelines to coastal property owners, city managers, and developers.


Numerical Analysis Of Explosion Characteristics Of Vent Gas From 18650 Lifepo4 Batteries With Different States Of Charge, Shi-Lin Wang, Xu Gong, Li-Na Liu, Yi-Tong Li, Chen-Yu Zhang, Le-Jun Xu, Xu-Ning Feng, Huai-Bin Wang Aug 2024

Numerical Analysis Of Explosion Characteristics Of Vent Gas From 18650 Lifepo4 Batteries With Different States Of Charge, Shi-Lin Wang, Xu Gong, Li-Na Liu, Yi-Tong Li, Chen-Yu Zhang, Le-Jun Xu, Xu-Ning Feng, Huai-Bin Wang

Journal of Electrochemistry

The combustion and explosion characteristics of lithium-ion battery vent gas is a key factor in determining the fire hazard of lithium-ion batteries. Investigating the combustion and explosion hazards of lithium-ion batteries vent gas can provide guidance for rescue and protection in explosion accidents in energy storage stations and new energy vehicles, thereby promoting the application and development of lithium-ion batteries. Based on this understanding and combined with previous research on gas production from lithium-ion batteries, this article conducted a study on the combustion and explosion risks of vent gas from thermal runaway of 18650 LFP batteries with different states of …


Winning Results Of The 2nd Xiamen University Short Video Abstract Contest For Science And Technology Papers, Editorial Office Of J.Electrochem. Aug 2024

Winning Results Of The 2nd Xiamen University Short Video Abstract Contest For Science And Technology Papers, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Winning Works From Journal Of Electrochemistry: The 2nd Xiamen University Short Video Abstract Contest For Science And Technology Journal Papers, Editorial Office Of J.Electrochem. Aug 2024

Winning Works From Journal Of Electrochemistry: The 2nd Xiamen University Short Video Abstract Contest For Science And Technology Journal Papers, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Recent Advances On Ruthenium-Based Electrocatalysts For Lithium-Oxygen Batteries, Yu-Zhe Wang, Zhuo-Liang Jiang, Bo Wen, Yao-Hui Huang, Fu-Jun Li Aug 2024

Recent Advances On Ruthenium-Based Electrocatalysts For Lithium-Oxygen Batteries, Yu-Zhe Wang, Zhuo-Liang Jiang, Bo Wen, Yao-Hui Huang, Fu-Jun Li

Journal of Electrochemistry

Rechargeable lithium-oxygen (Li-O2) batteries have attracted wide attention due to their high energy density. However, the sluggish cathode kinetics results in high overvoltage and poor cycling performance. Ruthenium (Ru)-based electrocatalysts have been demonstrated to be promising cathode catalysts to promote oxygen evolution reaction (OER). It facilitates decomposition of lithium peroxide (Li2O2) by adjusting Li2O2 morphologies, which is due to the strong interaction between Ru-based catalyst and superoxide anion (O2) intermediate. In this review, the design strategies of Ru-based electrocatalysts are introduced to enhance their OER catalytic kinetics in …


Rate Law For Photoelectrochemical Water Splitting Over Cuo, Bo-Yuan Gao, Wen-Hua Leng Aug 2024

Rate Law For Photoelectrochemical Water Splitting Over Cuo, Bo-Yuan Gao, Wen-Hua Leng

Journal of Electrochemistry

Photocatalytic splitting of water over p-type semiconductors is a promising strategy for production of hydrogen. However, the determination of rate law is rarely reported. To this purpose, copper oxide (CuO) is selected as a model photocathode in this study, and the photogenerated surface charge density, interfacial charge transfer rate constant and their relation to the water reduction rate (in terms of photocurrent) were investigated by a combination of (photo)electrochemical techniques. The results showed that the charge transfer rate constant is exponential-dependent on the surface charge density, and that the photocurrent equals to the product of the charge transfer rate constant …


2024 Electrochemical Research Paradigm Summer School Was Successfully Held, Editorial Office Of J.Electrochem. Aug 2024

2024 Electrochemical Research Paradigm Summer School Was Successfully Held, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


2024 World Fuel Cell Conference Held In Ningbo, Zhejiang, Editorial Office Of J.Electrochem. Aug 2024

2024 World Fuel Cell Conference Held In Ningbo, Zhejiang, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Upcoming Meeting-The 1st Young Investigator Symposium On Electrosynthesis, Chinese Chemical Society, Editorial Office Of J.Electrochem. Aug 2024

Upcoming Meeting-The 1st Young Investigator Symposium On Electrosynthesis, Chinese Chemical Society, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Polish Energy Sector’S Dependence On Lignite Mining: The Process Of Transition, Marek Widera, Wojciech Naworyta, Paweł Urbański Aug 2024

Polish Energy Sector’S Dependence On Lignite Mining: The Process Of Transition, Marek Widera, Wojciech Naworyta, Paweł Urbański

Journal of Sustainable Mining

This opinion study is devoted to the role of lignite in the Polish energy sector in recent decades, i.e., after the collapse of communism in 1989. Lignite is the primary source of electricity in Poland, second only to hard coal. More than 25–35% of Polish electricity was generated by lignite-fired power plants in 1990–2022. To meet the needs of the energy industry, 46–70 Mt of lignite was mined annually in that period. Hence, Poland was, and still is, one of the world leaders in lignite production. Despite the ongoing transition of the Polish energy sector, changes occur very slowly due …


A Petrophysical Modeling-Guided Method For Predicting Parameters Of Low-Permeability Reservoirs, Wang Rui, Li Fang, Liu Shiyou, Sun Wanyuan, Li Songling, Huang Sheng Aug 2024

A Petrophysical Modeling-Guided Method For Predicting Parameters Of Low-Permeability Reservoirs, Wang Rui, Li Fang, Liu Shiyou, Sun Wanyuan, Li Songling, Huang Sheng

Coal Geology & Exploration

Backgroud Accurately predicting reservoir parameters is significant for characterizing subsurface reservoirs, establishing gas accumulation patterns, releasing production capacity, and understanding fluid migration. The traditional approaches based on core measurement or mathematical-petrophysical modeling are limited by the strong multiplicity of solutions and low accuracy of elastic parameters inversion results, making it difficult to meet the demands of modern exploration.Objective and Methods To more effectively predict reservoir parameters, this study proposed a petrophysical modeling-guided method for predicting parameters of low-permeability reservoirs. With the convolutional neural network (CNN) as a deep learning framework, the proposed method can predict water saturation, clay content, …


Processing Of Impulse Noise In Magnetotelluric Data Based On Bidirectional Recurrent Imputation, Yang Kai, Liu Cheng, Li Han, He Jinglong Aug 2024

Processing Of Impulse Noise In Magnetotelluric Data Based On Bidirectional Recurrent Imputation, Yang Kai, Liu Cheng, Li Han, He Jinglong

Coal Geology & Exploration

Objective Magnetotelluric sounding is an exploration method to obtain the underground electrical structure by observing the natural electromagnetic field, which is easily disturbed by noise. Impulse noise, frequently occurring in magnetotelluric sounding, generally exhibits high amplitude and wide frequency bands, producing significant impacts on the data quality. Methods To suppress such noise, this study proposed a method based on a bidirectional recurrent imputation for time series (BRITS) model. First, the data segments with noise interference were deleted. Second, for the magnetotelluric time series with missing data to be imputed, training sets were constructed for imputation training of the BRITS model. …


Structure Optimization Of Foam Generator For Soft Coal Seam And Foaming Effect Simulation, Jin Xin Aug 2024

Structure Optimization Of Foam Generator For Soft Coal Seam And Foaming Effect Simulation, Jin Xin

Coal Geology & Exploration

Objective The application of air screw drilling technology in gas drainage borehole within soft coal seam presents challenges, including severe dust pollution, low drill bit lifespan, and great difficulty in borehole purification. The use of air screw foam drilling technology is an effective way to solve the problem. A foam generator with good foaming performance is one of the keys to implementing the foam drilling technology. However, most current foam generators could not meet the requirements. Methods In response to this issue, a small-sized foam generator was designed based on the spiral foam generator, with an air kinetic energy conversion …


Characteristics Of Gas Bursting And Application Of Layered Cutting Drilling In Outburst Coal Seam, Wang Yonglong, Zhao Aoqi, Yu Zaijiang, Wang Zhenfeng, Liu Xiao, Ma Denghui, Zhang Hui, Liu Chun Aug 2024

Characteristics Of Gas Bursting And Application Of Layered Cutting Drilling In Outburst Coal Seam, Wang Yonglong, Zhao Aoqi, Yu Zaijiang, Wang Zhenfeng, Liu Xiao, Ma Denghui, Zhang Hui, Liu Chun

Coal Geology & Exploration

Objective The overlimit gas bursting in the drilling process of outburst coal seam is a safety hazard that threatens the efficient production of the mine. The layered cutting drilling method helps to weaken the burst gas pressure in the borehole, but the characteristics of gas release around the trapezoidal borehole formed by layered cutting are unknown, which limits the structural design and application effect of the layered cutting drilling tool. Methods Herein, study was conducted based on the layered cutting boreholes with different layer spacing and layer thickness difference. Specifically, a mathematical model was established to analyze the gas flow …


Table Of Contents, The Editors Aug 2024

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Critical Drilling And Completion Techniques For Deep Coalbed Methane In The Shenfu Block And Their Applications, Wang Peng, Li Bin, Wang Kunjian, Zhang Hongjie, Zhang Yingchun, Du Jia, Zhang Linqiang, Wang Xiaoqi, Su Haiyan, Chen Guanghui, Yang Ruiyue Aug 2024

Critical Drilling And Completion Techniques For Deep Coalbed Methane In The Shenfu Block And Their Applications, Wang Peng, Li Bin, Wang Kunjian, Zhang Hongjie, Zhang Yingchun, Du Jia, Zhang Linqiang, Wang Xiaoqi, Su Haiyan, Chen Guanghui, Yang Ruiyue

Coal Geology & Exploration

Objective Deep coal seams exhibit high in-situ stress, moderate to high temperatures, ultra-low permeability, high compressibility, and significant heterogeneity, leading to the absence of mature technical systems for their exploitation presently. The complex geological characteristics of deep coal seams pose new technical challenges to their drilling and completion engineering, rendering it urgent to tackle theoretical and technical challenges in drilling and completion tailored to the geological characteristics of deep coal seam reservoirs. The purpose is to achieve the reserve growth and production addition of hydrocarbons in order to guarantee China’s strategic energy security. Methods Based on the pilot tests for …