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Analysis of marine debris at Alue Naga and Ulee Lheue beaches in Banda Aceh City using the transect method

Materials Today: Proceedings 2022年 63卷 S339-S345页

作者： Windari, Wulan Saiful, Saiful Gani, Asri Mahidin Master of Environment Management Postgraduate Program Syiah Kuala University Banda Aceh Indonesia Chemistry Department Faculty of Mathematics and Natural Science Syiah Kuala University Banda Aceh Indonesia Chemical Engineering Faculty of Engineering Syiah Kuala University Banda Aceh Indonesia Research Center for Environmental and Natural Resources Universitas Syiah Kuala Darussalam Banda Aceh 23111 Indonesia

Alue Naga Beach and Ulee Lheue Beach are beaches located in Banda Aceh City, Aceh Province, these two beaches have a fairly large role in the fields of fisheries, transportation, and tourism. During the last few years, the population growth rate of Banda Aceh City has increased by 2% per year, this causes the volume of waste generated to be even greater, unfortunately, the municipal waste management office cannot manage it fully. Most of the untreated waste enters water bodies and has the potential to pollute the marine and coastal environment. So it is necessary to do research to provide an overview of the level of marine debris pollution on the two beaches. This study uses the transect method, the waste obtained is grouped according to size and type. The results showed that marine debris on Ulee Lheue beach was found to be more numerous and varied than marine debris on Alue Naga beach. Overall, macro waste with a size range of 2.5−1 m was the most commonly found and plastic was the waste with the highest yield with a density value of 65.8 g/m2, an abundance of 6.56 items/m2, and a percentage of 75%. © 2022

关键词： Beaches

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Effects of Superabsorbent Polymers on Autogenous Shrinkage and Microstructure in Metakaolin-Based Cementitious Materials

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SSRN 2025年

作者： Palma e Silva, Arthur Aviz Capuzzo, Valdirene Maria Silva da Silva, Eugência Fonseca Agostinho, Lívia Borba Pereira, André Maués Brabo University of Brasília Postgraduate Program in Structures and Civil Construction DF BrasíliaCEP: 70910-900 Brazil Federal Fluminense University Department of Computer Science RJ Rio de JaneiroCEP: 22290-240 Brazil Federal University Uberlândia Postgraduate Program in Civil Engineering Minas Gerais UberlandiaCEP: 38408-100 Brazil

The use of superabsorbent polymers (SAPs) in combination with supplementary cementitious materials like metakaolin presents an opportunity to enhance concrete performance while addressing environmental concerns in construction, lowering CO2 emissions by clincker substitution. This study investigates the behavior of high-strength microconcrete incorporating SAPs and metakaolin, evaluating their feasibility and sustainability for construction applications. Three microconcrete and paste mixes were analyzed: a reference mix and two mixes containing 0.15% and 0.30% SAP by cement mass. All mixes included a 10% metakaolin substitution by cement mass and maintained the same water/cement ratio, without additional curing water for SAPs. Fresh-state tests assessed consistency and specific mass, while hardened-state tests measured elastic modulus. Autogenous shrinkage was evaluated through linear volumetric variation using dial gauges. Microstructural analysis of the pastes and microconcretes involved thermogravimetry, isothermal conduction calorimetry, and X-ray microtomography. The results highlight the beneficial effects of SAPs with metakaolin, including enhanced hardened state properties and refined pore structure, achieved despite the absence of extra curing water. SAPs contributed to increased pozzolanic activity in metakaolin, likely due to delayed water release from SAP desorption. Furthermore, SAPs effectively mitigated autogenous shrinkage, making their application in concrete mixes promising. These findings emphasize the dual benefit of improving concrete performance and advancing environmental sustainability, showcasing the potential of SAPs and metakaolin in producing high-performance, eco-friendly concrete solutions for the construction industry. © 2025, The Authors. All rights reserved.

关键词： Hardening

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Evaluation of an artificial intelligence-based model in diagnosing periodontal radiographic bone loss

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Clinical Oral Investigations 2025年第4期29卷 1-8页

作者： Cassiano, Luanny de Brito Avelino da Silva, Jordão Paulino Cassiano Martins, Agnes Andrade Barbosa, Matheus Targino Rodrigues, Katryne Targino Barbosa, Ádylla Rominne Lima da Silva Gomes, Gabriela Ellen Maia, Paulo Raphael Leite de Oliveira, Patrícia Teixeira de Sousa Lopes, Maria Luiza Diniz da Silva, Ivanovitch Medeiros Dantas de Aquino Martins, Ana Rafaela Luz Department of Dentistry Federal University of Rio Grande do Norte - UFRN Rio Grande do Norte Natal Brazil Postgraduate Program in Electrical and Computer Engineering Center of Technology Rio Grande do Norte Natal Brazil Department of Dentistry Federal University of Rio Grande do Norte Av. Senador Salgado Filho 1787 Rio Grande do Norte Natal 59056-000 Brazil

Objective: To develop an artificial intelligence model based on convolutional neural network for detecting and measuring periodontal radiographic bone loss (RBL). Materials and methods: Keypoint annotations were carried out in 595 digital bitewing radiographic images using a Computer Vision Annotation Tool. The dataset was splitted: 416 of these images were trained using the You Only Look Once version 8 architecture with pose estimation (YOLO-v8-pose), 119 images were destined for the validation set, and 60 images were used for the test set, resulting in a model capable of detecting keypoints related to the cementoenamel junction (CEJ) and alveolar bone crest (ABC). In order to evaluate the performance of the obtained model, the following metrics were analyzed: F1-Score, precision, sensitivity and mean average precision (mAP). Then, an algorithm was implemented to measure the RBL by calculating the Euclidean distance between CEJ and ABC. Results: The model achieved an F1-Score of 66,89%, precision of 61,1%, a sensitivity of 73,9% and an mAP of 73.8%. Conclusions: The developed model and its algorithm for identifying and measuring periodontal radiographic bone loss demonstrated promising performance, thereby presenting a potential tool for assisting in periodontal diagnosis. Further studies comparing the developed model with manual measurements performed by specialists are necessary for its validation. Clinical relevance: Applying artificial intelligence in clinical dental practice can support diagnosis, streamline clinical workflows, and inform treatment planning, representing a significant advancement in dental automation. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025.

关键词： Alveolar bone loss Computer neural networks Deep learning Periodontitis Radiography

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Development of a Methodology for Forecasting of Photovoltaic Generation in the Short and Medium Term Based on an Analysis of a Photovoltaic System and a Meteorological Forecasting Platform

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SSRN 2024年

作者： Rosso, André Possamai Rampinelli, Giuliano Arns Schaeffer, Lirio Federal University of Rio Grande do Sul Porto Alegre Brazil Postgraduate Program in Mining Metallurgical and Materials Engineering Antônio Marcelo Ferreira Street 41 Criciúma Santa Catarina88810-016 Brazil Federal University of Santa Catarina Araranguá Brazil Postgraduate Program in Energy and Sustainability Pedro João Pereira Street 150 Araranguá Santa Catarina88905-120 Brazil Postgraduate Program in Mining Metallurgical and Materials Engineering Aneron Correa de Oliveira Street 250 Porto Alegre Rio Grande do Sul 91410-070 Brazil

Uncertainties in PV production can make it challenging to dispatch energy into the electricity grid. Although PV storage solves this problem, predicting the solar photovoltaic (PV) energy produced is necessary to control the energy injected into the grid. In Brazil, photovoltaic solar energy has grown exponentially in recent years. The current scenario in Brazil is a synergy of legal, regulatory, research and development, fiscal, tax, and economic incentives. With the country's solar energy growth, there is a need to develop and apply methodologies for predicting photovoltaic generation. This article aims to develop a methodology (RRS) for predicting photovoltaic generation in the short (1h to 10h future) and medium (24h future) terms using the generation data from a grid-connected photovoltaic system and to compare it with the persistence method (PM). Numerical weather prediction (NWP) variables such as irradiance, cloud cover, and precipitation are input for next-day prediction models. Photovoltaic predictions for the next day's horizon show the most significant errors compared to predictions for the horizon a few hours ahead. The proposed RRS model is simple, easy to access and apply, and does not use irradiance data. In the RRS model, some parameters are already built in and do not need to be dealt with, such as soiling of the photovoltaic modules, shading, spectral mismatch of the photovoltaic cells with the radiation spectrum, losses due to mismatch, losses due to cabling, losses due to series and parallel resistance, among others. The application of the RRS methodology requires two searches/inputs. The first input is weather forecast data obtained from a weather forecasting platform, and the second is actual historical data on photovoltaic generation at the site where the method was developed. © 2024, The Authors. All rights reserved.

关键词： Weather forecasting

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Range of Motion Detection System in Humans Based on MediaPipe Special Flexion-Extension and Abduction-Adduction Movements 3

Range of Motion Detection System in Humans Based on MediaPip...

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3rd International Conference on Electronic and Electrical engineering and Intelligent System, ICE3IS 2023

作者： Mustar, Muhamad Yusvin Tryatmojo, Bintang Surya Hidayat, Maulana Wiyagi, Rama Okta Ulfa, Maria Fredianto, Meiky Ihsan, Muhammad Universitas Muhammadiyah Department of Electrical Engineering Yogyakarta Indonesia Research and Innovation Institute Universitas Muhammadiyah Center of Artificial Intelligence and Robotic Studies Yogyakarta Indonesia Universitas Muhammadiyah Postgraduate Program Master of Hospital Administration Yogyakarta Indonesia Universitas Muhammadiyah Faculty of Medicine and Health Sciences Yogyakarta Indonesia

ISBN: (纸本)9798350327762

This research offers an alternative for health workers to monitor the rehabilitation of a patient's Range of Motion (ROM) without using a goniometer instrument and attaching various sensors to the patient's body, based on a detection system using the MediaPipe library. The developed detection system measures angles concerning the patient's body ROM patterns. The algorithm in the MediaPipe library helps to produce line graphs of landmark pose which are then processed using the trigonometric gradient equation so that it can have to measure angles from ROM. The angle of ROM measured includes Flexion-Extension and Abduction-Adduction movements of the arms, legs, and body. The results of testing the detection system between the goniometer measurements and the detection results differ from the Right Arm Elbow Flexion-Extension movement to the Trunk Flexion-Extension movement having an angle difference. The most significant angle difference is in the Right Arm Elbow Abduction - Adduction movement of 9.1388°, and the minor difference is in the Right Leg Hip Abduction - Adduction movement of 2.15°. The most significant overall system error is in the Left Arm Elbow Flexion - Extension movement, with a general system error of 27%. The minor system error in Left Arm Elbow Abduction - Adduction movement is 11 %. © 2023 IEEE.

关键词： Errors

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Five years after the Brumadinho dam collapse: Evaluation of water quality based on combined analysis of land use and environmental data

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Science of the Total Environment 2024年 957卷 177619页

作者： Mello, Caio C.S. Leão, Monica M.D. Amorim, Camila C. Postgraduate Program in Sanitation Environment and Water Resources Federal University of Minas Gerais MG Belo Horizonte Brazil Department of Sanitary and Environmental Engineering Federal University of Minas Gerais MG Belo Horizonte Brazil

The collapse of the dam in the Paraopeba River watershed in 2019 triggered significant concerns regarding water quality in the region. This study aimed to assess, five years after the disaster, the effects on water quality and understand the underlying factors of environmental pressure contributing to the observed changes. To perform the evaluation, the study utilized surface water quality data pre-disaster (2012–2018) and post-disaster (2019–2023), environmental data regarding the identification of high-polluting potential industries operating in the region of interest, and land use for the watershed as a combined evaluation. Nonparametric statistical tests Kruskal-Wallis, complemented by Dunn's, were employed to assess the significance of changes in water quality parameters post-collapse. The results indicate a relatively stable baseline scenario of land use dominated by agriculture and pasture, with minor changes observed in forest cover and urban development. However, post-collapse assessments showed significant variations in water quality parameters, with turbidity exceeding conformity levels by up to 68 % (over 100 NTU), dissolved iron (Fe) by up to 70 % (over 0.3 mg.L–1), manganese (Mn) by up to 91 % (over 0.1 mg.L–1), dissolved aluminum (Al) by up to 83 % (over 0.01 mg.L–1), and lead (Pb) by up to 26 % (over 0.01 mg.L–1). Statistical tests suggested possible effects of the dam collapse on turbidity, pH, dissolved Fe, Mn, and dissolved Al. Temporal analysis showed constant effects on water quality, with notable increases in dissolved Fe and Mn concentrations observed upstream post-disaster and persistent impacts downstream. New mining activities licensed after 2019 may have contributed to the deterioration of water quality, highlighting the relevant relationship of anthropogenic activities and the environmental disaster in the Paraopeba River watershed. © 2024 Elsevier B.V.

关键词： Rivers

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Optimizing Wireless Sensor Network Planning: Integrating Biased Random-Key Genetic Algorithm and Local Branching for Scalable Solutions

Optimizing Wireless Sensor Network Planning: Integrating Bia...

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International Conference on Information Fusion

作者： Almir Antônio Monteiro Junior Diego Brandão Felipe Da Rocha Henriques Claudio M. De Farias Pedro Henrique González System Engineering and Computer Science Program Federal University of Rio de Janeiro Rio de Janeiro Brazil Computer Science Postgraduate Program Federal Center for Technological Education of Rio de Janeiro Rio de Janeiro Brazil

ISBN: (数字)9781737749769

ISBN: (纸本)9798350371420

This study addresses the Wireless Sensor Network Planning Problem with Multiple Sources/Destinations (WSNPMSD), an optimization challenge focused on reducing the sensor count within a network topology for a specified area, considering numerous sources and destinations. We introduce a hybrid strategy for tackling WSNP-MSD, particularly effective for large-scale scenarios, combining a Biased Random-key Genetic Algorithm with a Local Branching Technique. This methodology is justified by the limitations exact methods may encounter when the number of variables increases. Through computational experiments, we demonstrate the superiority of our proposed method over conventional exact methods in managing large instances of the WSNP-MSD.

关键词： Wireless communication Wireless sensor networks Network topology Planning Optimization Genetic algorithms

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Evaluating the Influence of Phase-Locked Loops on the Response of Grid-Following Inverter-Based Resources to Interconnection Transmission Line Faults

Evaluating the Influence of Phase-Locked Loops on the Respon...

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Workshop on Communication Networks and Power Systems (WCNPS)

作者： Pedro Henrique de Morais Martins Luciano Sales Barros Felipe Vigolvino Lopes Postgraduate Program in Renewable Energies Federal University of Paraíba Department of Computer Systems Federal University of Paraíba Department of Electrical Engineering Federal University of Paraíba

ISBN: (数字)9798331507152

ISBN: (纸本)9798331507169

In this paper, the influence of different Phase-Locked Loops (PLLs) on the fault response of a grid-following (GFL) Inverter-Based Resource (IBR) is evaluated. The analyzed IBR represents a wind power plant with rated power equal to 100 MVA, being composed of 50 turbines with 2 MVA each, whose controls follow the Brazilian grid code. Two PLL models are taken into account to conduct the proposed studies, which include the analysis of voltage and frequency estimated by each PLL, and currents injected into the IBR interconnection transmission line. The Synchronous Reference Frame (SRF) PLL and the Quadrature Signal Generator-based Second-Order Generalized Integrator (QSG-SOGI) PLL are considered, assessing their influence under different transmission line fault scenarios. The obtained results indicate that the PLL can present severe instabilities during faults, which can be more or less critical depending on the fault type and on the PLL type. Indeed, the results reveal that different PLLs can result in distinct behaviors of currents injected into the interconnection line, raising the importance of knowing the PLL structures when studies on IBR fault responses are of interest.

关键词： Power transmission lines Grid following Conferences Voltage Wind power generation Power system stability Frequency estimation Phase locked loops Inverter-based resource Turbines

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Utilizing SEM measurments in modelling monocrystaline silicon solar cell degradation due to an effective dust-layer

Utilizing SEM measurments in modelling monocrystaline silico...

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2021 International Telecommunications Conference, ITC-Egypt 2021

作者： Amr, Lamis Abdellatif, Sameh O. Kirah, Khaled Ghali, Hani. A. The British University in Egypt Renewable Energy Postgraduate Program Faculty of Engineering and FabLab Cairo Egypt Ain Shams University Faculty of Engineering Engineering Physics Department Cairo Egypt

ISBN: (纸本)9781665445733

In the current paper, we propose a modified SCAPS model using a Monocrystalline PV cell to demonstrate the optoelectronic impact of the dust accumulated layer thickness by considering it as an effective medium with time-dependent thickness variation. Following the proposed model, we have estimated the expected short circuit current degradation with respect to time under continuous dust accumulations, as well as the total output power of the cell. The data for the model was measured through conducting 6 weeks experiment in a deserted area using glass sheets to collect dust samples. These samples were analyzed using SEM, and the results were seeded to our simulation model. The current density degradation curves with respect to dust accumulation levels were plotted, where the short circuit current dropped by 55.5% at dust layer thickness 28.5\ \mu\mathrm{m} with almost fixed open-circuit voltage. © 2021 IEEE.

关键词： Silicon solar cells

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Belém 20|50 ºC: A New Model of Sustainable and Climate-Resilient Social Housing for Belém-Brazil

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SSRN 2024年

作者： Zemero, Bruno Ramos Barata, Márcio Santos Monteiro, Giovanna Bentes Braga, Jhonata Lima Gonçalves, Eduarda Lorrany Sousa dos Santos Batista, Vitor Michelon, Michelli Gonçalves da Cunha, Luís Filipe Brasil Dutra, Ana Beatriz Nobre Alves de Medeiros Machado, Rebecca Teixeira, Reyso Cunha Postgraduate Program in Architecture and Urbanism Federal University of Pará Brazil Faculty of Architecture and Urbanism Federal University of Pará Brazil Faculty of Computer Engineering Federal University of Pará Brazil

The city of Belém experiences a hot and humid equatorial climate and faces the threats of global warming, aiming to become the second hottest city in the world by 2050, according to The Washington Post. As the host of COP-30 in November 2025, the city requires special attention to ensure the safety and quality of life for its population. This research aims to provide sustainability (social, economic, and environmental) and resilience (mitigation and adaptation to climate change) through a prototype of Social Interest Housing (HIS) with the potential for replication in municipal and national housing policies. © 2024, The Authors. All rights reserved.

关键词： Housing

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