Artigos - Turismo - Rosana

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Glycerol determination by chronoamperometry using Ni(OH)2/RGO on carbon paste electrode
(2023-01-01) de Oliveira, João P. J. [UNESP]; de Sá, Acelino C.; de Sousa, Miguel S. P. [UNESP]; Zanette, Andréia F. [UNESP]; Torres, Giovanni B.; dos Santos, Renivaldo J. [UNESP]; Paim, Leonardo L. [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Estadual de Campinas (UNICAMP); Universidade de São Paulo (USP); Instituto Tecnológico Metropolitano
Glycerol is a by-product obtained in the transesterification reaction together with biodiesel, a necessary renewable fuel. The presence of glycerol in fuel can bring up environmental harm and engine damage, making fuel quality control important. In this context, composite electrodes (CE) were developed with low-cost materials like syringes, copper wire, graphite, and paraffin. The surface of composite electrodes was modified with reduced graphene oxide (RGO) and hydroxide nickel (Ni(OH)2). SEM, EDX, Raman, and FT-IR ATR characterized the developed material. The electrooxidation of glycerol in an alkaline medium containing 0.10 M of NaOH was investigated by CV. In the presence of glycerol, the modified electrode increased the anodic and cathodic peak current with an anodic peak potential shift to 0.54 V. The electrodes were employed in a study of the determination of glycerol in real biodiesel samples by a chronoamperometric technique. The modified electrode showed a sensitivity of 1.63 × 103 µA mM and a LOD for glycerol of 2.24 × 10–5 M (R = 0.996). The mean response time of the modified electrodes to glycerol was 1.85 s. These electrodes show good reproducibility and competitive detection limit compared to the literature. The proposed method presented satisfactory results, with 94.98 and 100.39% sample recoveries. Graphical abstract: [Figure not available: see fulltext.]
World federation of interventional and therapeutic neuroradiology (WFITN) federation assembly neurointerventional surgery safety checklist
(2023-01-01) Chen, Michael; Fargen, Kyle M; Mocco, J.; Siddiqui, Adnan H; Miyachi, Shigeru; Mahadevan, Jeyaledchumy; Ayudya, Sirintara Singhara Na; Churojana, Anchalee; Chryssidis, Steve; De Villiers, Laetitia; Rahman, Mohibur; Dey, Subash Kanti; Zhang, Hongqi; Wang, Donghai; Petrocelli, Sergio; Garbugino, Silvia; Kulcsar, Zsolt; Januel, Anne; Kocer, Naci; Manfre, Luigi; Tanaka, Michihiro; Matsumaru, Yuji; Suh, Sang Hyun; Yoon, Woong; de Freitas, Carlos [UNESP]; Mont’Alverne, Francisco; Desal, Hubert; Caroff, Jildaz; Lee, Wickly; Anil, Gopinathan; Harrichandparsad, Rohen; LeFeuvre, David; Agid, Ronit; Orbach, Darren B; Taylor, Allan; Rush University Medical Center; Wake Forest University; The Mount Sinai Health System; University at Buffalo Jacobs School of Medicine and Biomedical Sciences; Gates Vascular Institute; Aichi Medical University; Pantai Hospital Kuala Lumpur; Mahidol University; Siriaj Hospital; Flinders Medical Centre; Gold Coast University Hospital; National Institute of Neurosciences & Hospital; Bangabandhu Sheikh Mujib Medical University; Xuanwu Hospital; Qilu Hospital of Shandong University; Sanatorio Parque; Hospital de Clinicas Jose de San Martin; Zurich University Hospital; University Hospital Centre Toulouse; Cerrahpasa Medical School; IOM Mediterranean Oncology Institute; Kameda Medical Center; University of Tsukuba; Gangnam Severance Hospital Yonsei University; Chonnam National University Hospital; Universidade Estadual Paulista (UNESP); Hospital General de Fortaleza; University Hospital of Nantes; APHP; National Neuroscience Institute; National University Hospital; Leeds Teaching Hospitals NHS Trust; University of KwaZulu-Natal College of Health Sciences; University of Cape Town; Toronto Western Hospital; Boston Children's Hospital
Over the last 10 years, there has been a rise in neurointerventional case complexity, device variety and physician distractions. Even among experienced physicians, this trend challenges our memory and concentration, making it more difficult to remember safety principles and their implications. Checklists are regarded by some as a redundant exercise that wastes time, or as an attack on physician autonomy. However, given the increasing case and disease complexity along with the number of distractions, it is even more important now to have a compelling reminder of safety principles that preserve habits that are susceptible to being overlooked because they seem mundane. Most hospitals have mandated a pre-procedure neurointerventional time-out checklist, but often it ends up being done in a cursory fashion for the primary purpose of ‘checking off boxes’. There may be value in iterating the checklist to further emphasize safety and communication. The Federation Assembly of the World Federation of Interventional and Therapeutic Neuroradiology (WFITN) decided to construct a checklist for neurointerventional cases based on a review of the literature and insights from an expert panel.
Cationic dialdehyde cellulose microfibers for efficient removal of eriochrome black T from aqueous solution
(2023-07-01) Silva Gomes, Andressa [UNESP]; Vitória Guimarães Leal, Maria [UNESP]; Roefero Tolosa, Gabrieli [UNESP]; Camargo Cabrera, Flávio [UNESP]; Dognani, Guilherme [UNESP]; Eloízo Job, Aldo [UNESP]; Universidade Estadual Paulista (UNESP)
Materials based on cellulose have been widely used as a decontaminant agent of wastewater. However, it can not be found in the literature any application of the cationic dialdehyde cellulose (cDAC) in anionic dye removal. Therefore, this study aims a circular economy concept using sugarcane bagasse to obtain a functionalized cellulose by oxidation and cationization. cDAC was characterized by SEM, FT-IR, oxidation degree, and DSC. Adsorption capacity was evaluated by pH, kinetic, concentration effect, strength ionic tests, and recycling. The kinetic followed Elovich model (R2 = 0.92605 for EBT = 100 mg/L) and non-linear Langmuir model (R2 = 0.94542), which resulted in a maximum adsorption capacity of 563.30 mg/g. The cellulose adsorbent reached an efficient recyclability of 4 cycles. Thus, this work presents a potential material to become a new, clean, low-cost, recyclable, and environmentally friendly alternative for effluent decontamination-containing dyes.
Evaluation of tensile, thermal, and biological properties of natural rubber-based biocomposite with biosilicate and 45S5-K bioglass
(2023-06-10) Lima, Luiz R. M. [UNESP]; Caetano, Guilherme F.; Soares, Viviane O.; Santos, Renivaldo J. [UNESP]; Malmonge, José A. [UNESP]; Silva, Michael J. [UNESP]; Yarin, Alexander L.; Universidade Estadual Paulista (UNESP); FHO; Universidade de São Paulo (USP); Universidade Estadual de Maringá (UEM); University of Illinois at Chicago (UIC); Korea University
The objective of this work was to develop new NR-based biocomposite containing BioS and/or BL0 particles, which exhibit better tensile response, biocompatibility, and bioactivity for biomedical applications. Morphological, tensile, thermal, and biological tests were performed on the biocomposites to evaluate the influence of BioS and BL0 particles on the properties of the NR matrix. According to TG/DTG tests, the decomposition profiles of the NR/BioS and NR/BL0 biocomposites were similar to those of NR, whose main event could be seen in the 290–450°C temperature range, indicative of NR's structural degradation. Tensile analysis demonstrated that the addition of BioS or BL0 to the NR-based biocomposite improved the elastic modulus and the tensile strength at break (σat break) in comparison to NR. The σat break value of the NR matrix increased from 0.99 ± 0.06 MPa to 1.84 ± 0.09 and 2.29 ± 0.04 MPa for the NR/BioS and NR/BL0 specimens with 30 wt%. Indirect cytotoxicity testing revealed that NR, NR/BL0, and NR/BioS biocomposite specimens promote the attachment of MSCs cell, that is, greater than 70% viability as defined in ISO 10993-5:2009. The results indicate that BioS and BL0 particles have improved the tensile response and biological properties of the NR matrix, resulting in a range of potential biomedical applications.
Effect of torrefaction on the properties of briquettes produced from agricultural waste
(2023-02-01) Granado, Marcos Paulo Patta [UNESP]; Gadelha, Antonia Mabrysa Torres; Rodrigues, Deyvison Souza; Antonio, Graziella Colato; De Conti, Andrea Cressoni; Universidade Estadual Paulista (UNESP); Universidade Federal do ABC (UFABC)
In this study, briquettes produced from cassava rhizome, sugarcane bagasse and straw were torrefied at 250 °C for 90 min to verify the effects of the process on their structure and properties such as density, durability, energy content, and energy density. The briquettes had a relaxed density of 1270 kg/m3 for those produced from cassava rhizome, 1240 kg/m3 from sugarcane bagasse, and 1300 kg/m3 from sugarcane straw. The torrefaction procedure increased calorific value of the briquettes by 9–13-fold. However, changes in briquette strength were identified after torrefaction, with a longitudinal deformation of 12.9–26.6 % and cracks in its bodies. Consequently, fragments were produced after durability testing. Moreover, briquette density decreased by 36 % for cassava rhizome, 50 % for sugarcane bagasse, and 55 % for sugarcane straw. The produced cassava rhizome briquettes exhibited the highest energy yield when torrefied. Combining these technologies facilitates the use of residues from agriculture for energy generation.
Optimization Studies and Compositional Oil Analysis of Pequi (Caryocar brasiliense Cambess) Almonds by Supercritical CO2 Extraction
(2023-02-01) Mateus, Livia Silva; Dutra, Juliete Martins; Favareto, Rogério; da Silva, Edson Antônio; Ferreira Pinto, Leandro [UNESP]; da Silva, Camila; Cardozo-Filho, Lucio; Ciência e Tecnologia Goiano; Universidade Estadual do Oeste do Paraná; Universidade Estadual Paulista (UNESP); Universidade Estadual de Maringá (UEM)
Caryocar brasiliense Cambess (pequi) is the fruit of the pequizeiro tree found in the Brazilian Cerrado (savanna). Supercritical fluids have been used to effectively extract bioactive chemicals. In light of the paucity of research on the supercritical extraction of pequi, in this study, experimental tests were conducted on the extraction of pequi almond oil using supercritical CO2; the optimal extraction conditions were determined, and the fatty acids and active compounds in the oil were characterized. The experiments were conducted using the Box–Behnken experimental design of a three-variable system: pressure (15, 20, and 25 MPa), temperature (303.15, 318.15, and 333.15 K), and flow rate (2, 3, and 5 g.min−1). The optimal extraction conditions were 318.15 K, 25 MPa, and 5.0 g.min−1, which yielded 27.6 wt% of oil. The experimental kinetic curves were described using a second-order quadratic model (based on the Sovová model), which demonstrated a satisfactory correspondence with the kinetic curves. Significant amounts of squalene, stigmasterol, oleic fatty acids, and palmitic fatty acids were detected in pequi almond oil.
Recycling waste polyurethane from the refrigeration industry as filler in SBR/NR composites for industrial applications
(2023-04-10) Hiranobe, Carlos Toshiyuki [UNESP]; Tolosa, Gabrieli Roefero [UNESP]; de Almeida Santos, Gleyson Tadeu [UNESP]; de Oliveira, João Pedro Jenson; Budemberg, Eduardo Roque [UNESP]; da Silva, Michael Jones [UNESP]; Cabrera, Flávio Camargo [UNESP]; Job, Aldo Eloizo [UNESP]; Paim, Leonardo Lataro [UNESP]; Torres, Giovanni Barrera; dos Santos, Renivaldo José [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Estadual de Campinas (UNICAMP); Instituto Tecnológico Metropolitano (ITM)
The refrigeration industry produces millions of tons of waste polyurethane (PU) every year, which can cause environmental damage and human health problems. This article analyzes the use of waste PU as filler in composites made of styrene butadiene rubber (SBR) and natural rubber (NR) to produce shoe soles. The interfacial interaction of said filler was evaluated by the Flory–Rehner method (swelling) using the equation developed by Lorenz–Park. The results of this evaluation were later compared with those obtained by the Mooney–Rivlin method using the data from stress–strain tests. According to the results of the tensile strength tests, the composites filled with waste PU present stress–strain curves that are like those of metallic materials that have low elastic strength but high plastic strength. Using the Lorenz–Park equation, the filled composites examined in this study exhibited values above 0.7, which means a strong filler–rubber interaction. Scanning Electron Microscopy and Fourier-Transform Infrared Spectroscopy were used to investigate the morphology of the composites in detail.
Production of new concrete with leather tannery waste used as partial replacement of the natural sand
(2023-03-01) Canhada, João C. S. [UNESP]; Paiva, Fábio F. G.; Shinohara, Gabriel M. M. [UNESP]; Okimoto, Fernando [UNESP]; Hiranobe, Carlos T. [UNESP]; Teixeira, Silvio R. [UNESP]; Job, Aldo E. [UNESP]; Santos, Renivaldo J. [UNESP]; Universidade Estadual Paulista (UNESP); University of Western São Paulo - UNOESTE
Leather production is a technology that boosts the economy because of its versatility and durability. However, the wastes generated throughout the process are categorized as toxic due to the high chrome concentration. In this work, the effects caused by the incorporation of leather shavings (wet blue) on the mechanical and physical properties of the concrete composite and the possibility of neutralizing the chrome's toxicity are evaluated. Namely, the leather shavings partially replace natural aggregates. In order to characterize the mechanical, physical, and morphological properties of the concretes, 7, 14, and 28 days-aged samples were evaluated. A leaching test is also performed to determine the efficiency of chromium encapsulation in the cement matrix. The experiments present that the workability of concrete decreases as the leather shavings content increases. We add a superplasticizer additive was to make the concrete workable, but a decrement in the mechanical properties similar to the samples without additive, is noted. With respect to the physical properties, the reduction of water permeability indicates a more durable material. Experimental findings highlight the ability to use the concrete with leather shavings as an alternative construction material.
Physical-Mechanical Properties of Chartwell® Coupling Agent-Treated Calcium Carbonate and Silica-Reinforced Hybrid Natural Rubber Composites
(2022-11-01) Ribeiro, Gabriel Deltrejo [UNESP]; Hiranobe, Carlos Toshiyuki [UNESP]; da Silva, José Francisco Resende [UNESP]; Torres, Giovanni Barrera; Paim, Leonardo Lataro [UNESP]; Job, Aldo Eloizo [UNESP]; Cabrera, Flávio Camargo [UNESP]; dos Santos, Renivaldo José [UNESP]; Universidade Estadual Paulista (UNESP); Instituto Tecnológico Metropolitano (ITM)
In this work investigated the possibility of applying a superficial treatment to ultra-fine calcium carbonate aiming to improve its interaction with the polymer chains of natural rubber so it does not act just as a filler. Commercial processes commonly use 40 phr of Silica as reinforcement filler. Here, we have evaluated the partial replacement of Silica by two types of calcium carbonate into hybrid natural rubber composites, untreated ultra-fine calcium carbonate and with ultra-fine calcium carbonate treated with 2% Chartwell C-515.71HR®. We added calcium carbonate fillers to the composite mixtures (as replacements for commercial silica treated with silane) and studied their influence on the vulcanization process. According to our findings, between 25% and 75% of the silica can be replaced with treated calcium carbonate, and up to 30 parts of CaCO3 can be combined with 100 parts of NR without compromising the properties of the polymer matrix (NR), which generates economic advantages for this industry. Treated calcium carbonate was able to link the inorganic and organic parts of the composite due to its bifunctionality; hence, it can be used as a filler to partially replace silica in hybrid NR composites.
Chemical treatment of sugarcane bagasse and its influence on glyphosate adsorption
(2022-01-01) Da Penha Bezerra, Williene Faria [UNESP]; Dognani, Guilherme [UNESP]; De Alencar, Laura Neves [UNESP]; Parizi, Marcela Prado Silva [UNESP]; Boina, Rosane Freire [UNESP]; Cabrera, Flávio Camargo; Job, Aldo Eloízo [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Estadual de Maringá (UEM)
Due to the production rates of sugarcane, nowadays, the sugarcane bagasse stemming in the sugar and alcohol industry is the agro-industrial waste produced in greater volume throughout in Brazil. In 2019, about 192 million tons of this waste were generated. The use of this waste has been the aim of researches around the world, with emphasis on applications that aim to meet the prerogatives of the concept of circular economy. Within this scenario, sugarcane bagasse (SB) was treated in an alkaline medium, forming an adsorbent material, SBNaOH. The effects of chemical treatment were evaluated for surface properties and for glyphosate removal in an aqueous medium. The adsorptive phenomenon was studied through isotherm tests. The results obtained were fitted to classical models of Langmuir, Freundlich and Dubinin-Radushkevich. The characterization indicated that the chemical treatment promoted an important change in the surface of the residue, increasing the surface area. SB and SBNAOH had a feasible behavior as adsorbent and good performance in the removal of the herbicide, presenting values greater than 65% of under all working conditions. The theoretical adsorption saturation governed by Dubinin-Radushkevich (qS) was in the order of 8.988 mg/g (R2=0.988) for SB at 120 minutes of contact and maximum adsorption capacity by Langmuir (Qmax) was 13.720 mg/g (R2=0.984) for SBNaOH at 40 minutes of contact. The process was governed by the exchange or sharing of electrons. The adsorbate is distributed heterogeneously on the SB surface, justifying the presence of active sites with greater ionic strength, and homogeneously on the SBNaOH surface (monolayer). In general, the treated sugarcane bagasse, coming from an agro-industrial residue, proved to be an alternative and promising biosorbent for the removal of glyphosate from aqueous systems, thus generating a new application of this residue.
Social valuation of protected cultural assets: the railway heritage between Jundiaí and Campinas (Brazil)
(2022-01-01) Oliveira, Eduardo Romero de [UNESP]; Silva, M. M.; Deus, Júlia de; Santana Junior, Evandro; Costa, Amanda [UNESP]; Lara, Ana Patricia [UNESP]; Santos, Brenda; Berata, Thaís [UNESP]; Bueno, Victória [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Estadual de Campinas (UNICAMP); Universidade de São Paulo (USP)
Given the shortcomings of traditional heritage preservation practices in understanding the values that justify heritage protection, it is necessary to critically re-evaluate these practices adopted to physically protect the cultural asset, which rarely include the local values ascribed by the surrounding communities. This reflection motivated the development of this study that aims to examine the social valuation ascribed to protected railway assets on the route Jundiaí-Campinas (Brazil), in order to compare the different identified values and reflect on the integrated actions of railway heritage preservation and management. To this end, a values-based approach (VBA) was used, a methodology employed for and centred on heritage preservation, which focuses on understanding the local community as one of the protagonists in the heritage valuation process. Applying the different techniques of the VBA method revealed that other values, besides the traditional ones dominant in the specialised dissemination of the subject, also have an impact on the heritage asset. By integrating these community values to the protection and management practices of the cultural asset, it is indeed possible to significantly protect and safeguard not only the monumental object but also its values.
A Machine Learning Strategy Based on Kittler’s Taxonomy to Detect Anomalies and Recognize Contexts Applied to Monitor Water Bodies in Environments
(2022-05-01) Dias, Maurício Araújo [UNESP]; Marinho, Giovanna Carreira [UNESP]; Negri, Rogério Galante [UNESP]; Casaca, Wallace [UNESP]; Muñoz, Ignácio Bravo; Eler, Danilo Medeiros [UNESP]; Universidade Estadual Paulista (UNESP); University of Alcalá (UAH)
Environmental monitoring, such as analyses of water bodies to detect anomalies, is recog-nized worldwide as a task necessary to reduce the impacts arising from pollution. However, the large number of data available to be analyzed in different contexts, such as in an image time series acquired by satellites, still pose challenges for the detection of anomalies, even when using comput-ers. This study describes a machine learning strategy based on Kittler’s taxonomy to detect anomalies related to water pollution in an image time series. We propose this strategy to monitor environ-ments, detecting unexpected conditions that may occur (i.e., detecting outliers), and identifying those outliers in accordance with Kittler’s taxonomy (i.e., detecting anomalies). According to our strategy, contextual and non-contextual image classifications were semi-automatically compared to find any divergence that indicates the presence of one type of anomaly defined by the taxonomy. In our strategy, models built to classify a single image were used to classify an image time series due to domain adaptation. The results 99.07%, 99.99%, 99.07%, and 99.53% were achieved by our strat-egy, respectively, for accuracy, precision, recall, and F-measure. These results suggest that our strategy allows computers to recognize contexts and enhances their capabilities to solve contextualized problems. Therefore, our strategy can be used to guide computational systems to make different decisions to solve a problem in response to each context. The proposed strategy is relevant for im-proving machine learning, as its use allows computers to have a more organized learning process. Our strategy is presented with respect to its applicability to help monitor environmental disasters. A minor limitation was found in the results caused by the use of domain adaptation. This type of limitation is fairly common when using domain adaptation, and therefore has no significance. Even so, future work should investigate other techniques for transfer learning.
Determination of Cr(VI) in leather residues using graphite/paraffin composite electrodes modified with reduced graphene oxide nanosheets
(2022-08-15) Oliveira, João P. J. de [UNESP]; Hiranobe, Carlos T. [UNESP]; Torres, Giovanni B.; Santos, Renivaldo J. dos [UNESP]; Paim, Leonardo L. [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Estadual de Campinas (UNICAMP); Programa de Ingeniería de Diseño Industrial
In this study, we determined the Cr(VI) in samples of tanned leather residues by differential pulse voltammetry (DPV) using graphite/paraffin composite electrodes modified with reduced graphene oxide nanosheets (referred to as GPEs/nsRGO). After the modification, the composite electrodes were characterized by two electrochemical techniques (i.e., cyclic voltammetry, CV, and electrochemical impedance spectroscopy, EIS), scanning electron microscopy, and Raman spectroscopy. The electroanalytical method was applied using the GPEs/nsRGO. An analytical curve was obtained in a Clark-Lubs buffer solution (pH = 1), with a linear concentration range from 25.0 to 392.0 μmol L−1 and a limit of detection (LOD) of 1.01 μmol L−1. The GPEs/nsRGO showed good reproducibility in their manufacturing process and good response repeatability with an RSD of 4.59% over twelve measurements. These composite electrodes showed excellent selectivity, which was demonstrated by analyses in the presence of metal ions (Ca2+, Zn2+, Mg2+, Fe3+, Co2+, Na+, and Cu2+) that did not interfere in the analysis of Cr(VI). The GPEs/nsRGO were applied to the determination of Cr(VI) in real samples of wet-blue leather and leather ash using DPV. This approach was validated using the sample recovery method, where it presented values from 95.6 to 108.2%. The proposed method showed satisfactory results compared to the literature and can be considered a good alternative for the determination of Cr(VI) in aqueous samples.
NO and NO2 emissions of waste tire pyrolysis oil (TPO) blended with diesel in a flameless combustor
(Springer, 2022-09-20) Chumpitaz, Raul G.; Barbosa, Jean A.; Andrade, Jose C.; Azevedo, Claudia G. [UNESP]; Andrade, Ricardo A.; Coronado, Christian J. R.; Fed Univ Itajuba (UNIFEI); Natl Space Res Inst; Universidade Estadual Paulista (UNESP)
Combustion systems can use tire pyrolysis oil (TPO) due to its high energy content. The amount of nitrogen and sulfur present in the TPO should result in NOx and SO2 emissions when combustion occurs. A flameless combustion regime can reduce pollutant emissions, mainly NOx, with greater thermal efficiency. This work aims to analyze the NO and NO2 emission in different diesel fuel mixtures with TPO, 5% (TPO5), and 10% (TPO10) by mass, in a flameless regime. A combustor was used operating with a maximum heat input of 13 kW and an effervescent injector promoting an average Sauter diameter of 33.89 +/- 3.77 mu m. The uniform temperature profile within the combustor characterizes the flameless combustion regime that was reached after 50 min for diesel and after 40 min for TPO5 and TPO10 from the ignition. TPO5 and TPO10 have similar NO emissions in flameless combustion. The NO2 emission increases with the TPO content in the mixture.
Adaptive Robust Linear Programming Model for the Charging Scheduling and Reactive Power Control of EV Fleets
(Ieee, 2021-01-01) Arias, Nataly Banol; Lopez, Juan C.; Rider, Marcos J.; Franco, John Fredy [UNESP]; IEEE; Universidade Estadual de Campinas (UNICAMP); Universidade Estadual Paulista (UNESP)
High penetration of electric vehicles (EVs) triggers challenges and opportunities for distribution system operators. Inverter-based EV chargers with active/reactive power control can be used to coordinate the EV fleet's charging process while providing local volt/var regulation. This paper proposes an adaptive robust programming model for the charging scheduling of EV fleets that exploits their capability to locally support the grid via reactive power control. The proposed model aims at maximizing the aggregator's revenue while considering the worst-case scenario in terms of active power losses at the supporting grid. Operational constraints of unbalanced three-phase distribution networks under demand uncertainty are also enforced. The proposed robust model is a min-max problem that can be linearized and solved using a column-and-constraint generation (C&CG) method. Tests performed in a 25-node distribution system illustrate the EV fleet's capacity to support the grid while minimizing the total energy not supplied.
Secondary Reserve Provision through a Smart Aggregation Strategy of Electric Vehicles
(Ieee, 2021-01-01) Guzman, Cindy P. [UNESP]; Romero, Ruben [UNESP]; Arias, Nataly Banol; Rider, Marcos J.; Franco, John Fredy [UNESP]; IEEE; Universidade Estadual Paulista (UNESP); Universidade Estadual de Campinas (UNICAMP)
The electric vehicles (EVs) are flexible loads that can be controlled to provide secondary reserve services (RSs) to transmission network operator (TNO) via charging or stop charging the batteries. An aggregator, as an intermediary agent between the EVs owners and the TNO, can schedule RSs through EV charging control. This paper proposes a smart aggregation strategy for the EV charging control that allows the aggregator's participation in the reserve market, while guaranteeing the energy required by the EVs for transportation. The smart strategy, based on a linear programming model, coordinates the charging of EVs, and allows offering RSs and selling energy produced by distributed generation units to maximize the aggregator's profit. Results for a case study with 1,000 vehicles show that the strategy effectively contributes to the offering of RSs to the TNO, while satisfying the energy requirements of the EV owners.
Efficient Multi-start with Path Relinking Search Strategy for Transmission System Expansion Planning
(2021-01-01) Silva, Silvia M. L.; Faria, Lucas Teles; Romero, Ruben; Franco, John F.; Universidade Estadual Paulista (UNESP)
Transmission expansion planning is a complex problem that deals with the selection of new transmission lines that guarantee meeting future demand/generation and technical limits with the minimal investment cost. The transmission expansion planning problem has been solved through approaches and techniques aimed at reducing the computational effort required for its solution. Nevertheless, finding the optimal solution or even good-quality solutions for large-scale transmission systems is still challenging. In that context, an efficient multi-start with path relinking search strategy for the transmission expansion planning problem is proposed. The proposed strategy has two phases: constructive phase and local search. In the former, the multi-start applies a diversification process to guide the search along different regions to obtain good-quality solutions. Then, the local search phase executes an intensive search in the neighborhood of the best feasible solutions found in the constructive phase. The intensification process is performed in two steps: application of the Villasana-Garver-Salon algorithm in the best solutions after consecutive removal of transmission lines and path relinking using elite solution pairs. Tests performed using data from four systems show the efficiency of the proposed search strategy. Thus, the optimal solutions were obtained with a very low computational effort.
The Industrial Landscape. Approach to the Design of a Methodological Basis for its Study, Enhancement, and Intervention
(2022-02-01) Dorado, María Isabel Alba; de Oliveira, Eduardo Romero [UNESP]; Arquitectura de la Universidad de Málaga; Universidade Estadual Paulista (UNESP)
The industrial landscape currently configures a phenomenon of extraordinary complexity and diversity whose study has been belatedly approached by scientific activity in general. This article aims to deepen the knowledge of these landscapes and advance in the design of a series of guidelines that serve as a methodological basis for their study, enhancement and intervention from their heritage and cultural consideration. The method used is based on prior knowledge of these landscapes and the most relevant methodological trends applied to the study of the landscape from the second half of the 20th century to the present in an international and interdisciplinary field of reflection. Subsequently, we proceed to analyze to what extent the set of methodological approaches previously studied allow us to respond to the specific needs of those landscapes generated by industrial decline. From this study it is concluded that at present we find ourselves in a situation at a conceptual and methodological level that is insufficient to address in depth the study and intervention of these landscapes. This confirms the need to advance in the contribution of improvements and innovations that lead to the design of a methodology for these landscapes that considers, among others, issues such as their specificity and identity, their complexity, the diversity of scales in which they participate, its dynamic and highly anthropized character, etc. through a method that approaches from its study to its management, integrating an interdisciplinary approach and incorporating the use of digital tools.
Cassava Waste Torrefaction for Energy Purposes
(2022-01-01) Granado, Marco Paulo P. [UNESP]; Machado, Gabriel T.; Padilla, Elias R. D. [UNESP]; Yamaji, Fábio M.; De Conti, Andrea C. [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Federal de São Carlos (UFSCar)
Biomass torrefaction consists of a heat treatment process that by slow heating of the material promotes the release of moisture and volatile constituents of low molecular weight. In this work, the objective was to carry out the torrefaction process in cassava rhizome in order to analyze its effect on the energy properties of the waste. The residue collected in natura was dried, ground and torrefied in two different forms: with granulated material and with material densified in briquettes; performing a torrefaction process at temperatures of 200 and 300 °C, with torrefaction time of 30 and 60 minutes. According to results, the cassava rhizome torrefaction can increase its initial high heating value of 16.3 MJ/kg from 21 to 51%, and decrease from 81% to 42% its volatile content; while torrefied briquettes showed little variation in their properties, except for the briquettes torrefied at 300 °C for 60 minutes. Therefore, when performing torrefaction of densified biomass, there is a need to use higher temperature and longer torrefaction time when compared to granular biomass.
A Specialized Long-Term Distribution System Expansion Planning Method with the Integration of Distributed Energy Resources
(2022-01-01) De Lima, Tayenne D. [UNESP]; Franco, John F. [UNESP]; Lezama, Fernando; Soares, Joao; Universidade Estadual Paulista (UNESP); Polytechnic Institute of Porto (ISEP/IPP)
The electrical distribution system (EDS) has undergone major changes in the last decade due to the increasing integration of distributed generation (DG), particularly renewable energy DG. Since renewable energy resources have uncertain generation, energy storage systems (ESSs) in the EDS can reduce the impact of those uncertainties. Besides, electric vehicles (EVs) have been increasing in recent years leveraged by environmental concerns, bringing new challenges to the operation and planning of the EDS. In this con, new approaches for the distribution system expansion planning (DSEP) problem should consider the distributed energy resources (DG units, ESSs, and EVs) and address environmental impacts. This paper proposes a mixed-integer linear programming model for the DSEP problem considering DG units, ESSs, and EV charging stations, thus incorporating the environmental impact and uncertainties associated with demand (conventional and EVs) and renewable generation. In contrast to other approaches, the proposed model includes the simultaneous optimization of investments in substations, circuits, and distributed energy resources, including environmental aspects (CO2 emissions). The optimization method was developed in the modeling language AMPL and solved via CPLEX. Tests carried out with a 24-node system illustrate its effectiveness as a valuable tool that can assist EDS planners in the integration of distributed energy resources.

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