bluuebunny/crossref_metadata_2025 huggingface dataset:
A Circuit Theory Perspective on the Modeling and Analysis of Vibration Energy Harvesting Systems: A Review
Authors: Bonnin Michele , Song Kailing , Traversa Fabio L. , Bonani Fabrizio
Published: February 2023

This paper reviews advanced modeling and analysis techniques useful in the description, design, and optimization of mechanical energy harvesting systems based on the collection of energy from vibration sources. The added value of the present contribution is to demonstrate the benefits of the exploitation of advanced techniques, most often inherited from other fields of physics and engineering, to improve the performance of such systems. The review is focused on the modeling techniques that apply to the entire energy source/mechanical oscillator/transducer/electrical load chain, describing mechanical–electrical analogies to represent the collective behavior as the cascade of equivalent electrical two-ports, introducing matching networks enhancing the energy transfer to the load, and discussing the main numerical techniques in the frequency and time domains that can be used to analyze linear and nonlinear harvesters, both in the case of deterministic and stochastic excitations.
Numerical Study on Surface Reconstruction and Roughness of Magnetorheological Elastomers
Authors: Valencia José Antonio , Restrepo Johans , Salinas Hernán David , Restrepo Elisabeth
Published: February 2023

A methodology is implemented to deform the surface of a magnetorheological elastomer (MRE) exposed to an external magnetic field by means of data matrix manipulation of the surface. The elastomer surface is created randomly using the Garcia and Stoll method to realize a nonuniform morphology similar to that found in real MREs. Deformations are induced by means of the translations of the magnetic particles inside the elastomer, under the influence of a uniform magnetic field, generating changes in the surface roughness. Our model computes these deformations using a three-dimensional Gaussian function bounded at 2 standard deviations from its mean value, taking as the standard deviation value the radius of the particle that causes the deformation. To find the regions deformed by the particles, we created a methodology based on the consultation, creation and modification of a system of matrices that control each point of the random surface created. This methodology allows us to work with external files of initial and subsequent positions of each particle inside the elastomer, and allows us to manipulate and analyze the results in a smoother and faster way. Results were found to be satisfactory and consistent when calculating the percentage of surface deformation of real systems.
Simulation Analysis of the Safety of High-Energy Hydroxyl-Terminated Polybutadiene (HTPB) Engine under the Impact of Fragments
Authors: Liu Zheng , Nie Jianxin , Fan Wenqi , Tao Jun , Jiang Fan , Guo Tiejian , Gao Kun
Published: February 2023

The safety of solid rocket engine use seriously affects the survivability and combat effectiveness of weaponries. To study the engine safety against fragment in complex battlefield environments, the fragment impact safety simulation study of a high-energy four-component HTPB propellant solid engine (hereafter referred to as high-energy HTPB propellant engine) was conducted. The equation of state parameters and reaction rate equation parameters of the detonation product of high-energy HTPB propellant were calibrated by using a 50 mm diameter cylinder test and Lagrange test combined with genetic algorithm. The nonlinear dynamics software LS-DYNA was used to build a finite element model of the fragment impact engine and simulate the mechanical response of the high-energy HTPB propellant under different operating conditions. This study shows that the critical detonation velocity decreases with the increase of the number of fragments. When the number of fragments is more than 5, the influence of this factor on the critical detonation velocity is no longer obvious. Under the same loading strength conditions, the greater the metal shell strength and the greater the shell wall thickness, the more difficult it is for the high-energy HTPB propellant to be detonated by the shock. This study can provide a reference for the design and optimization analysis of solid rocket engine fragment impact safety.
Patient Engagement in Health Research: Perspectives from Patient Participants
Authors: Easley Julie , Wassersug Richard , Matthias Sharon , Tompson Margaret , Schneider Nancy D. , O’Brien Mary Ann , Vick Bonnie , Fitch Margaret
Published: February 2023

Background and purpose: Over the past decade, patient engagement (PE) has emerged as an important way to help improve the relevance, quality, and impact of health research. However, there is limited consensus on how best to meaningfully engage patients in the research process. The goal of this article is to share our experiences and insights as members of a Patient Advisory Committee (PAC) on a large, multidisciplinary cancer research study that has spanned six years. We hope by sharing our reflections of the PAC experiences, we can highlight successes, challenges, and lessons learned to help guide PE in future health research. To the best of our knowledge, few publications describing PE experiences in health research teams have been written by patients, survivors, or family caregivers themselves. Methods: A qualitative approach was used to gather reflections from members of the Patient Advisory Committee regarding their experiences in participating in a research study over six years. Each member completed an online survey and engaged in a group discussion based on the emergent themes from the survey responses. Results: Our reflections about experiences as a PAC on a large, pan-Canadian research study include three overarching topics (1) what worked well; (2) areas for improvement; and (3) reflections on our overall contribution and impact. Overall, we found the experience positive and experienced personal satisfaction but there were areas where future improvements could be made. These areas include earlier engagement and training in the research process, more frequent communication between the patient committee and the research team, and on-going monitoring regarding the nature of the patient engagement. Conclusions: Engaging individuals who have experienced the types of events which are the focus of a research study can contribute to the overall relevance of the project. However, intentional efforts are necessary to ensure satisfactory involvement.
Surveillance Post Surgery for Retroperitoneal Soft Tissue Sarcoma
Authors: Whitaker John , Nessim Carolyn , Almond Max , Ford Samuel J.
Published: February 2023

Complete en bloc surgical resection offers the best opportunity for the cure of primary retroperitoneal sarcomas (RPS). The potential for disease recurrence, in the form of both loco-regional recurrence and distant metastases, underpins the rationale for postoperative surveillance. There is a paucity of high-quality evidence underpinning follow-up for RPS patients, and most practice guidelines draw from expert opinion and evidence from soft tissue sarcomas of the extremities. The available observational retrospective data analysis has failed to demonstrate that high-intensity radiological surveillance improves the overall survival in patients. The lack of a robust evidence base has given rise to variations in approaches to post-operative surveillance strategies adopted by specialist centres managing RPS across the world. More high-quality prospective research is needed and planned to more clearly support surveillance approaches that balance oncologic outcomes, patient-centric care, and health service value. Risk stratification tools exist and are available for use in routine practice. Their use will likely support more individualised post-operative surveillance moving forward. Surveillance will likely be underpinned by serial radiological imaging for the medium term. However, developments in genomics offer hope for biomarkers such as ctDNA to impact patient care positively in the future and further support individualised patient care pathways.
Disparities in Access to Thoracic Surgeons among Patients Receiving Lung Lobectomy in the United States
Authors: Halloran Sean J. , Alvarado Christine E. , Sarode Anuja L. , Jiang Boxiang , Sinopoli Jillian , Linden Philip A. , Towe Christopher W.
Published: February 2023

Objective: Lung lobectomy is the standard of care for early-stage lung cancer. Studies have suggested improved outcomes associated with lobectomy performed by specialized thoracic surgery providers. We hypothesized that disparities would exist regarding access to thoracic surgeons among patients receiving lung lobectomy for cancer. Methods: The Premier Hospital Database was used to identify adult inpatients receiving lung lobectomy from 2009 to 2019. Patients were categorized as receiving their lobectomy from a thoracic surgeon, cardiovascular surgeon, or general surgeon. Sample-weighted multivariable analysis was performed to identify factors associated with provider type. Results: When adjusted for sampling, 121,711 patients were analyzed, including 71,709 (58.9%) who received lobectomy by a thoracic surgeon, 36,630 (30.1%) by a cardiovascular surgeon, and 13,373 (11.0%) by a general surgeon. Multivariable analysis showed that thoracic surgeon provider type was less likely with Black patients, Medicaid insurance, smaller hospital size, in the western region, and in rural areas. In addition, non-thoracic surgery specialty was less likely to perform minimally-invasive (MIS) lobectomy (cardiovascular OR 0.80, p < 0.001, general surgery OR 0.85, p = 0.003). Conclusions: In this nationally representative analysis, smaller, rural, non-teaching hospitals, and certain regions of the United States are less likely to receive lobectomy from a thoracic surgeon. Thoracic surgeon specialization is also independently associated with utilization of minimally invasive lobectomy. Combined, there are significant disparities in access to guideline-directed surgical care of patients receiving lung lobectomy.
Physicians’ Opinion on Intraoperative Radiotherapy as a Therapeutic De-Escalation Option in Older Women with Early Breast Cancer
Authors: Tallet Agnès , Rey Dominique , Casanova Clémence , Lecourtois Delphine , Bergeaud Marie , Bendiane Marc-Karim , Mancini Julien
Published: February 2023

Background: Intraoperative radiotherapy (IORT) is a therapeutic de-escalation option in older women with low-risk early breast cancer (EBC). A qualitative study was implemented to describe EBC physicians’ points of view on IORT as a de-escalation option. Methods: Recorded face-to-face and telephone semi-structured interviews were conducted among diverse physicians from seven French comprehensive cancer centers. Interview transcripts were grouped as corpus to construct a typology. Thematic analysis was performed. Results: Positions toward IORT were contrasted between the 16 participating physicians. Five fully supported IORT as a de-escalation option, four were not in favor, and seven had a more reserved or neutral opinion. Points of divergence concerned treatment efficacy, treatment duration, side effects and sequelae, psychological impact, compliance with adjuvant endocrine therapy, logistical constraints, financial cost, and availability of other techniques of partial breast irradiation. Physicians in favor of IORT emphasized direct benefits for the patient, and those against pointed the lack of specific guidelines, risk of lost opportunity in older women with long life expectancy, and challenges of shared decision making. Conclusions: Despite national policies to preserve cancer patients’ quality of life and increase their participation in medical decision making, therapeutic de-escalation using IORT is not consensual among physicians. Further efforts are needed to promote patient-centered care.
Canada’s First Joint Oncology-Allergy Clinic: Successful Desensitization to Trastuzumab Following Severe Anaphylactic Reaction in Which Epinephrine Was Inappropriately Withheld
Authors: Robinson Madeline , Geirnaert Marc , Anderson Brady , McKibbin Lundy
Published: February 2023

Background: Recognition of anaphylaxis and differentiation from other infusion reactions in an oncology setting is imperative; epinephrine is the recommended treatment for anaphylaxis and should be administered immediately to patients in whom anaphylaxis is suspected. Trastuzumab has a potentially tremendous oncological benefit, and when hypersensitivity reactions occur, rechallenge with desensitization protocols has become more common. Oncology presents a unique situation in which repeat drug exposure after a serious adverse reaction is often warranted due to the mortality risk of untreated cancer—allergists can assist with both symptom assessment and risk mitigation. Case presentation: This case showcases successful desensitization in a 43-year-old female with locally advanced HER2-positive breast cancer following a severe anaphylactic reaction to trastuzumab, in which epinephrine was not administered. We report the establishment of the Medical Oncology and Allergy Clinic: Canada’s first multidisciplinary clinic aimed at expediting the assessment and management of oncology patients with adverse drug reactions (including chemotherapy, contrast media, antimicrobials) and those with primary and acquired immunodeficiency. Conclusions: We propose this multidisciplinary clinic model as a treatment framework moving forward, with the goal of continuing first-line therapies in cancer patients who develop drug-hypersensitivity (i.e., through desensitization). This case highlights the unmet need for a multidisciplinary approach to the management of oncology patients who experience hypersensitivity reactions.
FANET Routing Protocol Analysis for Multi-UAV-Based Reconnaissance Mobility Models
Authors: Kim Taehwan , Lee Seonah , Kim Kyong Hoon , Jo Yong-Il
Published: February 2023

Different from mobile ad hoc networks (MANETs) and vehicular ad hoc networks (VANETs), a flying ad hoc network (FANET) is a very low-density network where node topology changes rapidly and irregularly. These characteristics, the density, mobility, and speed of flight nodes, affect the performance of FANET. Furthermore, application scenarios and environmental settings could affect the performance of FANETs. In this paper, we analyzed the representative FANET protocols, AODV, DSDV, and OLSR, according to mobility models, SRWP, MP, RDPZ, EGM, and DPR, under the multi-UAV-based reconnaissance scenario. We evaluated them in terms of the number of nodes, network connectivity, mobility model’s reconnaissance rate, speed of nodes, and ground control station (GCS) location. As a result, we found that AODV showed the highest PDR performance (81%) with SRWP in multiple UAV-based reconnaissance scenarios. As for a mobility model under the consideration of reconnaissance rate, SRWP was excellent at 76%, and RDPZ and EGM mobility models were reasonable at 62% and 60%, respectively. We also made several interesting observations such as how when the number of nodes increases, the connectivity of the network increases, but the performance of the routing protocol decreases, and how the GCS location affects the PDR performance of the combination of routing protocols and mobility models.
Motion Control System Design for a Novel Water-Powered Aerial System for Firefighting with Flow-Regulating Actuators
Authors: Huynh Thinh , Kim Young-Bok
Published: February 2023

Flying water-jet propulsion devices, such as jet boards, jet packs, and jet bikes, can execute complex flight maneuvers. However, they require the direct involvement of trained operators to control, and their applications are very limited. In this study, we design an effective controller for a novel water-powered aerial system that aims for autonomous firefighting missions, especially at or in bodies water. Unlike existing water-powered systems, an assembly of flow-regulating actuators is proposed to fully operate the system in three-dimensional space. The paper first formulates the system dynamics by coupled partial ordinary differential equations. Then, the nonlinear controller is designed to ensure the desired system motion and stability. The design takes distinct characteristics of the system, such as coupling, under actuation, and effects of the hose conveying the water, into consideration so that the system is stabilized and uniform ultimate boundedness is achieved. Computational studies in comparison with previous control methods validated the superiority and feasibility of the proposed control system.
The Effect of On-Site Potentials on Supratransmission in One-Dimensional Hamiltonian Lattices
Authors: Bountis Tassos , Macías-Díaz Jorge E.
Published: February 2023

We investigated a class of one-dimensional (1D) Hamiltonian N-particle lattices whose binary interactions are quadratic and/or quartic in the potential. We also included on-site potential terms, frequently considered in connection with localization phenomena, in this class. Applying a sinusoidal perturbation at one end of the lattice and an absorbing boundary on the other, we studied the phenomenon of supratransmission and its dependence on two ranges of interactions, 0<α<∞ and 0<β<∞, as the effect of the on-site potential terms of the Hamiltonian varied. In previous works, we studied the critical amplitude As(α,Ω) at which supratransmission occurs, for one range parameter α, and showed that there was a sharp threshold above which energy was transmitted in the form of large-amplitude nonlinear modes, as long as the driving frequency Ω lay in the forbidden band-gap of the system. In the absence of on-site potentials, it is known that As(α,Ω) increases monotonically the longer the range of interactions is (i.e., as α⟶0). However, when on-site potential terms are taken into account, As(α,Ω) reaches a maximum at a low value of α that depends on Ω, below which supratransmission thresholds decrease sharply to lower values. In this work, we studied this phenomenon further, as the contribution of the on-site potential terms varied, and we explored in detail their effect on the supratransmission thresholds.
Future Mathematics Teachers’ Perceptions towards Inclusion in Secondary Education: University of Granada
Authors: Crisol-Moya Emilio , Caurcel-Cara María Jesús , Peregrina-Nievas Paula , Gallardo-Montes Carmen del Pilar
Published: February 2023

Designing and implementing inclusive practices is considered one of the basic actions for the construction of inclusive education. Actions depend largely on teachers’ attitudes, which can be modified by the training they receive. This study analyzes 73 future mathematics teachers’ perceptions of the diversity training received in the Master in Compulsory Secondary Education and Post-Secondary, Vocational Training and Language Teaching (MAES), as well as their attitudes towards diversity at the University of Granada (Spain). The participants’ ages ranged from 22 to 50 years (M = 27.12, SD = 6.45); 47.9% were cisgender women and 52.1% were cisgender men. This research was a non-experimental, descriptive, and multivariate study, developed under the assumption of the quantitative methodological paradigm. The result revealed that attention to diversity should play an important role in the teachers’ future teaching practice. Nevertheless, they were dissatisfied with the initial training received, considered themselves not qualified enough to face diversity in their classrooms, and they had an ambivalent attitude toward attention to diversity. However, attitudes and educational levels were more favorable in the case of women, older participants, and among those who had had contact with people with SNES. It is concluded that it is appropriate to continue to influence the attitudes in relation to this issue, since pedagogical training on the factors that condition the teaching–learning process in terms of attention to diversity provides greater effectiveness in this field.
Review on Research Methods for Studying Transition from Early Childhood Education to Primary Education
Authors: González-Moreira Alba , Ferreira Camino , Vidal Javier
Published: February 2023

The transition from early childhood to primary education is a process of changes that students undergo. Recent studies indicate that it is necessary to involve all actors in research: teachers, families, and students. Nevertheless, some researchers point to an “adult-centred” view, justified by the lack of linguistic communication among 5–7-year-olds. This study aims to describe the methods used in research on the transition from Early Childhood Education to Primary Education and to evaluate which methods support the participation of all actors involved. We conducted a systematic review of empirical studies between 2016 and 2021. The data show, on the one hand, that students of such a young age are not usually included in these studies. However, there has been an increase in studies that rely on students’ opinions and perceptions. On the other hand, studies that include all actors involved in the transition are a minority. Students of such a young age are not usually included in these studies. When they are included, adapted information collection tools are used. Only by having the students and triangulating the information among all participants is it possible to provide complete information on the process. In addition, there is a lack of action research designs to offer comprehensive and practical improvement actions.
Applicability of WorldCover in Wind Power Engineering: Application Research of Coupled Wake Model Based on Practical Project
Authors: Zhang Jing , Chen Jixing , Liu Hao , Chen Yining , Yang Jingwen , Yuan Zongtao , Li Qingan
Published: February 2023

This paper discusses how the incorporation of high-resolution ground coverage dataset ESA WorldCover into a wind flow field and wake simulation calculation, as well as the use of the coupled wake model for wind farm output simulation, can improve the accuracy of wind resource assessment using engineering examples. In the actual case of grid-connected wind farms in central China, SCADA wind speed data is reconstructed to the free flow wind speed in front of the wind turbine impeller using the transfer function of the nacelle, and the wind farm is modeled using OpenWind software, simulating the wind speed at the height of each wind turbine hub and each wind turbine output. The results show that when other initial data are consistent, using ESA’s high-precision land cover dataset WorldCover 10 m to make roughness lengths which improves the wind farm output simulation accuracy by 8.91%, showing that it is worth trying to apply WorldCover 10 m to the wind farm simulation design. At the same time, this case is used to compare and analyze the application of the Eddy-Viscosity wake model and the two coupled wake models based on the Eddy-Viscosity wake model. The results show that the coupled wake model will have higher accuracy than the Deep Array Eddy Viscosity wake model and it is 1.24% more accurate than the Eddy Viscosity wake model, and the ASM Eddy Viscosity wake model is 5.21% more accurate than the Eddy Viscosity wake model.
d-q Small-Signal Model for Grid-Forming MMC and Its Application in Electromagnetic-Transient Simulations
Authors: Freitas Cleiton M. , Watanabe Edson H. , Monteiro Luís F. C.
Published: February 2023

The modular multilevel converter (MMC) is a keystone of modern energy transmission systems. Consequently, there is an ongoing pursue for mathematical models to represent it under different configurations and control approaches. In short, this paper introduces an analytical Thévenin-equivalent model for representing the MMC when it is controlled with inner current- and an outer voltage-loop altogether. The model is based on a linearized representation of the converter and conveys the dynamics of passive components, such as submodule capacitors and arm reactors, as well as both control loops. Besides that, the proposed model is divided into a close-loop transfer matrix and the equivalent impedance matrix, both of which represent the relationships between the ac-side dq voltages and currents. We also propose a framework for implementing electromagnetic–transient simulations using the impedance model of this power electronic converter. The framework reduces a multi-bus power grid to a multi-input multi-output (MIMO) feedback system where impedance/admittance matrices of the MMC and other grid elements compose its loops. For validation purposes, it is considered a three-bus power grid comprising one MMC and another two grid-connected VSC. The proposed model was validated by comparing its results with a switching-level PSCAD model of the system.
Environmental Impact of Plastic Recycling in Terms of Energy Consumption: A Comparison of Japan’s Mechanical and Chemical Recycling Technologies
Authors: Shan Chaoxia , Pandyaswargo Andante Hadi , Onoda Hiroshi
Published: February 2023

In Japan, mechanical plastic recycling has been widely practiced. In recent years, the chemical recycling method has been gaining interest, especially due to its high-quality products similar to virgin materials. Understanding the environmental impact of both methods from the energy consumption standpoint is crucial so that attempts to preserve plastic resources can be based in the most energy-sustainable way. This research aims to determine the environmental impact of mechanical recycling and two types of chemical recycling technologies (coke oven and gasification) by analyzing their energy usage and environmental loads. The results relating to the electricity consumption and water usage show that mechanical recycling results in a 17% share of global warming potential (GWP), coke oven 51%, and gasification 32%. Although mechanical recycling results in a lower GWP, chemical recycling yields highly valuable products and byproducts that can be reused in its processes, such as steam and industrial water, reducing the overall environmental load. These recovered materials are also potentially useful for other industrial processes in an industrial symbiosis ecosystem.
Optimal Design of PV Inverter Using LCOE Index
Authors: Tadbiri-Nooshabadi Morteza , Schanen Jean-Luc , Farhangi Shahrokh , Iman-Eini Hossein , Rizet Corentin
Published: February 2023

This work uses design optimization of a power electronics converter to achieve the best levelized cost of energy in a PV application. The methodology uses detailed models of power electronics’ active and passive components to determine the cost and performances of the solid-state energy conversion and connect them to the system-level vision. The deterministic algorithm used for converter sizing allows taking into account a large number of variables and constraints. Methodology, models, and some illustrations of the results are provided in this paper. A sensitivity analysis was also conducted on the cost model.
Two-Outputs Nonlinear Grey Box Model for Lithium-Ion Batteries
Authors: da Silva Cynthia Thamires , Dias Bruno Martin de Alcântara , Araújo Rui Esteves , Pellini Eduardo Lorenzetti , Laganá Armando Antônio Maria
Published: February 2023

Storing energy efficiently is one of the main factors of a more sustainable world. The battey management system in energy storage plays an extremely important role in ensuring these systems’ efficiency, safety, and performance. This battery management system is capable of estimating the battery states, which are used to give better efficiency, a long life cycle, and safety. However, these states cannot be measured directly and must be estimated indirectly using battery models. Therefore, accurate battery models are essential for battery management systems implementation. One of these models is the nonlinear grey box model, which is easy to implement in embedded systems and has good accuracy when used with a good parameter identification method. Regarding the parameter identification methods, the nonlinear least square optimization is the most used method. However, to have accurate results, it is necessary to define the system’s initial states, which is not an easy task. This paper presents a two-outputs nonlinear grey box battery model. The first output is the battery voltage, and the second output is the battery state of charge. The second output was added to improve the system’s initial states identification and consequently improve the identified parameter accuracy. The model was estimated with the best experiment design, which was defined considering a comparison between seven different experiment designs regarding the fit to validation data, the parameter standard deviation, and the output variance. This paper also presents a method for defining a weight between the outputs, considering a greater weight in the output with greater model confidence. With this approach, it was possible to reach a value 1000 times smaller in the parameter standard deviation with a non-biased and little model prediction error when compared to the commonly used one-output nonlinear grey box model.
Optimal SOFC-CHP Installation Planning and Operation Model Considering Geographic Characteristics of Energy Supply Infrastructure
Authors: Owaku Takashi , Yamamoto Hiromi , Akisawa Atsushi
Published: February 2023

Combined heat and power (CHP) is crucial for promoting thorough energy conservation and advanced energy use, aimed toward greenhouse gas reduction. Solid oxide fuel cell (SOFC)-CHP is expected to be introduced as a measure against global warming and has been the focus of attention, and this study examined the effects of its introduction. This study introduces a linear programming evaluation model that can simulate optimized facility configuration and operation, based on the power supply and demand. The novelty of the proposed model is the consideration of geographic characteristics, which influences parameters dependent on gas transportation infrastructure and electricity. A sensitivity analysis was conducted considering the number of units and location of SOFC-CHP introductions in the National Capital Region of Japan. As a result, it was predicted that SOFC-CHP would likely begin to be introduced in areas where there is a large shadow price difference between electricity and gas at each node. The total power generation will decrease, as transmission and distribution losses decrease, owing to the diffusion of SOFC-CHP installed in the vicinity of demand. The widespread use of SOFC-CHP is an economically feasible CO2 emissions reduction pathway. These results will help assess the introduction of various distributed power sources in addition to SOFC-CHP to reduce CO2 emissions.
Nonlinear Lyapunov Control of a Photovoltaic Water Pumping System
Authors: Jouili Khalil , Madani Adel
Published: February 2023

In this study, we present an alternative maximum power point tracking technique used in a solar water pumping system to produce the maximum power for modifying the amount of pumped water. This technique was actually created primarily to regulate the duty ratio of the buck converter. In order to control the solar array operating point in order to track the maximum power point, a nonlinear control approach based on the input–output feedback linearizing technique and the Lyapunov stability theory is used. By adjusting the irradiation level, the introduced controller-containing photovoltaic generator direct current (DC) motor pump system was put to the test. Our control method was modeled in Matlab-Simulink, and simulation results were used to show that it significantly outperformed a directly connected solar generator-energized pumps operational system in terms of power extraction performance under various sunlight conditions.
Multi-Objective Electromagnetic Design Optimization of a Power Transformer Using 3D Finite Element Analysis, Response Surface Methodology, and the Third Generation Non-Sorting Genetic Algorithm
Authors: Hernandez Concepcion , Lara Jorge , Arjona Marco A. , Melgoza-Vazquez Enrique
Published: February 2023

This paper presents a multi-objective design optimization of a power transformer to find the optimal geometry of its core and the low- and high-voltage windings, representing the minimum power losses and the minimum core and copper weights. The optimal design is important because it allows manufacturers to build more efficient and economical transformers. The approach employs a manufacturer’s design methodology, which is based on the usage of the laws of physics and leads to an analytical transformer model with the advantage of requiring a low amount of computing time. Afterward, the multi-objective design optimization is defined along with its constraints, and they are solved using the Non-Sorting Genetic Algorithm III (NSGA-III), which finds a set of optimal solutions. Once an optimal solution is selected from the Pareto front, it is necessary to fine-tune it with the 3D Finite Element Analysis (FEA). To avoid the large computing times needed to carry out the 3D Finite Element (FE) model simulations used in multi-objective design optimization, Response Surface Methodology (RSM) polynomial models are developed using 3D FE model transformer simulations. Finally, a second multi-objective design optimization is carried out using the developed RSM empirical models that represent the cost functions and is solved using the NSGA-III. The numerical results of the optimal core and windings geometries demonstrate the validity of the proposed design methodology based on the NSGA-III. The used global optimizer has the feature of solving optimization problems with many cost functions, but it has not been applied to the design of transformers. The results obtained in this paper demonstrate better performance and accuracy with respect to the commonly used NSGA-II.
Energy Design Synthesis: Algorithmic Generation of Building Shape Configurations
Authors: Storcz Tamás , Ercsey Zsolt , Horváth Kristóf Roland , Kovács Zoltán , Dávid Balázs , Kistelegdi István
Published: February 2023

The building industry is responsible for a significant degree of energy consumption in the world, causing negative climate changes and energy supply uncertainties due to low energy efficiency as well as the high resource demand of construction. Consequently, energy design optimization has become an important research field. Passive design strategies are one of the most definitive factors concerning energy-related building development. The given architectural problem calls for a method that can create all potentially feasible building geometries, thus guaranteeing the optimal solution which is addressed in the current paper. To reach this requirement, the necessity of a modular space arrangement system and architectural selection rules were determined, focusing on the relationship between the rules and the generation of geometries with mathematical rigor. Next, the architecture-based congruency analysis performed, further reduced the number of simulation cases. With the simulations, it is illustrated how the building shape versions affect the heating energy demands: the performance of the configurations themselves. Results clearly illustrate the importance of the synthesis step of the architectural design.
The Transition of Scientific Research from Biomass-to-Energy/Biofuels to Biomass-to-Biochemicals in a Biorefinery Systems Framework
Authors: Giuliano Aristide
Published: February 2023

Only through renewable carbon source valorization will it be possible to obtain a high-impact transition from a fossil-based system to a renewable-based system [...]
Organic Solar Cells: From Fundamental to Application
Authors: Jiang Yu , Bai Youjun , Wang Shenghao
Published: February 2023

An organic solar cell (OSC) uses p-type and n-type organic layers sandwiched between a transparent electrode and a metallic electrode [...]
Combustion Characteristics of Hydrogen/Air Mixtures in a Plasma-Assisted Micro Combustor
Authors: Cinieri Giacomo , Fontanarosa Donato , De Giorgi Maria Grazia
Published: February 2023

This work performs an analysis of plasma-assisted non-premixed H2-air flames in Y-shaped micro combustors in the presence of field emission dielectric barrier discharge (FE-DBD) plasma actuators. The combustion, flow, and heat transfer characteristics are numerically investigated, and the effect of sinusoidal plasma discharges on combustion performance is examined at various equivalence ratios (φ). A coupled plasma and chemical kinetic model is implemented, using a zero-dimensional model based on the solution of the Boltzmann equation and the ZDPlasKin toolbox to compute net charges and radical generation rates. The estimated body forces, radical production rates, and power densities in the plasma regions are then coupled with hydrogen combustion in the microchannel. Plasma-assisted combustion reveals improvements in flame length and maximum gas temperature. The results demonstrate that FE-DBDs can enhance mixing and complete the combustion of unreacted fuel, preventing flame extinction. It is shown that even in cases of radical and thermal quenching, these plasma actuators are essential for stabilizing the flame.
Fault Location for Distribution Smart Grids: Literature Overview, Challenges, Solutions, and Future Trends
Authors: De La Cruz Jorge , Gómez-Luna Eduardo , Ali Majid , Vasquez Juan C. , Guerrero Josep M.
Published: February 2023

Thanks to smart grids, more intelligent devices may now be integrated into the electric grid, which increases the robustness and resilience of the system. The integration of distributed energy resources is expected to require extensive use of communication systems as well as a variety of interconnected technologies for monitoring, protection, and control. The fault location and diagnosis are essential for the security and well-coordinated operation of these systems since there is also greater risk and different paths for a fault or contingency in the system. Considering smart distribution systems, microgrids, and smart automation substations, a full investigation of fault location in SGs over the distribution domain is still not enough, and this study proposes to analyze the fault location issues and common types of power failures in most of their physical components and communication infrastructure. In addition, we explore several fault location techniques in the smart grid’s distribution sector as well as fault location methods recommended to improve resilience, which will aid readers in choosing methods for their own research. Finally, conclusions are given after discussing the trends in fault location and detection techniques.
Mechanical Characterization of Cemented Paste Backfill
Authors: Pan Andrew , Grabinsky Murray
Published: February 2023

Mechanical characterization is important to the design and analysis of cemented paste backfill (CPB) structures. Unconfined compressive strength (UCS) tests have been widely used owing to their relative simplicity to characterize a material’s response to unconfined compressive loading. However, the UCS represents a single strength parameter and does not fully describe the material’s strength (or failure) envelope. In this study, we analyzed UCS tests with direct shear and uniaxial tensile strength tests conducted on the same CPB materials to provide mechanical characterization of CPB under a more complete range of loading conditions. The results demonstrate the Mohr–Coulomb failure envelope provides a consistent description of strengths arising from the three different test methods. Furthermore, a better estimate of the tensile strength is UCS/4, which is considerably higher than the conventional assumption that the tensile strength is equal to USC/10 or UCS/12. This has a significant impact on the assessed required strengths particularly for undercut designs using Mitchell’s sill mat analysis method and suggests that in future the conventional UCS tests should be complemented with direct tension and direct shear tests to improve underground designs using CPB.
Linking Artificial Light at Night with Human Health via a Multi-Component Framework: A Systematic Evidence Map
Authors: Liu Yang , Yu Changda , Wang Keli , Kwan Mei-Po , Tse Lap Ah
Published: February 2023

The effects of artificial light at night (ALAN) on human health have drawn increased attention in the last two decades. Numerous studies have discussed the effects of ALAN on human health on diverse topics. A broader scope of how ALAN may affect human health is thus urgently needed. This paper depicts a systematic evidence map in a multi-component framework to link ALAN with human health through a comprehensive literature review of English research articles in the past two decades. A three-phase systematic review was conducted after a generalized search of relevant articles from three publication databases, namely Scopus, the Web of Science, and PubMed. In total, 552 research articles were found in four categories and on numerous topics within our framework. We cataloged the evidence that shows direct and indirect as well as positive and negative effects of ALAN on human physical and mental health. We also summarized the studies that consider ALAN as a social determinant of human health. Based on our framework and the systematic evidence map, we also suggest several promising directions for future studies, including method design, co-exposure and exposome studies, and social and environmental justice.
The Role of Spatial Exploration and Territoriality in Establishing Gilthead Seabream (Sparus aurata) Hierarchies, and Their Effects upon Underlying Stress Physiology
Authors: Dara Mariano , Dioguardi Maria , Vazzana Mirella , Vazzana Irene , Carbonara Pierluigi , Alfonso Sébastien , Cammarata Matteo
Published: February 2023

Territoriality, spatial exploration and social hierarchy are strictly related behaviors in gregarious fishes, and are often under-appreciated in farms where the individuals are confined within crowded spaces. In this study, we investigated the role of spatial exploration, elucidating the importance of time upon forming the social organization, and the role of the territoriality in gilthead seabream (Sparus aurata), using two experimental approaches. In the first approach, three fish were placed sequentially in the aquarium with an interval of two days (sequential model), while in the second (simultaneous model), two fish were simultaneously placed in an aquarium divided by a barrier which was removed after a certain period of time. To study the effect of social stress and spatial perception in the two models, we monitored behavior (aggressive acts and feeding priority), integrated with the evaluation of physiological and cellular stress parameters, such as phagocytosis, cortisol, glucose, and blood osmolarity levels. After the establishment of the social hierarchy in the “sequential model”, we observed that the levels of cortisol and an immunological cell-mediated marker were higher in subordinate individuals than in the dominant ones. We observed a different modulation of phagocytic activity in peritoneal cavity cells between dominant and subordinates, demonstrating that social stress acts upon immune response. Differently from the first model, no behavioral, physiological, or phagocytic differences were found between the two fish involved in the simultaneous model, where both fish acted as co-dominants, defending their territory. The study achieved a deeper understanding of the role of spatial exploration, territorial dominance and intraspecific interaction in gilthead seabream, and elucidated the link between them and physiological stress indicators. The results highlight aspects of interest to the aquaculture industry, showing the importance of a greater focus on rearing conditions, finding solutions to mitigate crowding effects and promoting the quality of aquacultural products.
Application of Three-Dimensional Digital Photogrammetry to Quantify the Surface Roughness of Milk Powder
Authors: Ding Haohan , Wilson David I. , Yu Wei , Young Brent R. , Cui Xiaohui
Published: February 2023

The surface appearance of milk powders is a crucial quality property since the roughness of the milk powder determines its functional properties, and especially the purchaser perception of the milk powder. Unfortunately, powder produced from similar spray dryers, or even the same dryer but in different seasons, produces powder with a wide variety of surface roughness. To date, professional panelists are used to quantify this subtle visual metric, which is time-consuming and subjective. Consequently, developing a fast, robust, and repeatable surface appearance classification method is essential. This study proposes a three-dimensional digital photogrammetry technique for quantifying the surface roughness of milk powders. A contour slice analysis and frequency analysis of the deviations were performed on the three-dimensional models to classify the surface roughness of milk powder samples. The result shows that the contours for smooth-surface samples are more circular than those for rough-surface samples, and the smooth-surface samples had a low standard deviation; thus, milk powder samples with the smoother surface have lower Q (the energy of the signal) values. Lastly, the performance of the nonlinear support vector machine (SVM) model demonstrated that the technique proposed in this study is a practicable alternative technique for classifying the surface roughness of milk powders.
Monitoring Moroccan Honeys: Physicochemical Properties and Contamination Pattern
Authors: Massous Abir , Ouchbani Tarik , Lo Turco Vincenzo , Litrenta Federica , Nava Vincenzo , Albergamo Ambrogina , Potortì Angela Giorgia , Di Bella Giuseppa
Published: February 2023

The physicochemical traits and an array of organic and inorganic contaminants were monitored in monofloral honeys (i.e., jujube [Ziziphus lotus], sweet orange [Citrus sinensis], PGI Euphorbia [Euphorbia resinifera] and Globularia alyphum) from the Moroccan Béni Mellal-Khénifra region (i.e., Khénifra, Beni Méllal, Azlal and Fquih Ben Salah provinces). Moroccan honeys were in line with the physicochemical standards set by the European Union. However, a critical contamination pattern has been outlined. In fact, jujube, sweet orange, and PGI Euphorbia honeys contained pesticides, such as acephate, dimethoate, diazinon, alachlor, carbofuran and fenthion sulfoxide, higher than the relative EU Maximum Residue Levels. The banned 2,3′,4,4′,5-pentachlorobiphenyl (PCB118) and 2,2′,3,4,4′,5,5′-heptachlorobiphenyl (PCB180) were detected in all samples and quantified in jujube, sweet orange and PGI Euphorbia honeys; while polycyclic aromatic hydrocarbons (PAHs), such as chrysene and fluorene, stood out for their higher contents in jujube and sweet orange honeys. Considering plasticizers, all honeys showed an excessive amount of dibutyl phthalate (DBP), when (improperly) considering the relative EU Specific Migration Limit. Furthermore, sweet orange, PGI Euphorbia and G. alypum honeys were characterized by Pb exceeding the EU Maximum Level. Overall, data from this study may encourage Moroccan governmental bodies to strengthen their monitoring activity in beekeeping and to find suitable solutions for implementing more sustainable agricultural practices.