bluuebunny/crossref_metadata_2025 huggingface dataset:
Agrivoltaic Engineering and Layout Optimization Approaches in the Transition to Renewable Energy Technologies: A Review
Authors: Reasoner Meagan , Ghosh Aritra
Published: September 2022

As more nations move towards net-zero emission goals by 2050, research into the coupling of photovoltaics (PV) and agriculture has increased into a new sector of agrivoltaics (AV). Measurement of the Land Equivalent Ratio (LER) has allowed researchers to develop methods for optimizing the agrivoltaic system. Studies on innovative engineering technologies related to photovoltaic tracking along with new generation PV cells were reviewed to determine the factors that influence optimization. This review also considered AV farm layouts and how different spacing, height, and density impact the shading under the panels. As panels block the light from hitting the plants, the photosynthetically active radiation (PAR) changes and alters plant growth. The shading, however, also creates micro-climates that have beneficial qualities in terms of water usage and PV efficiency. The overall review investigated the research of the last five years into AV optimization and the implications for future AV developments.
Supercritical CO2 Assisted Electrospray to Produce Poly(lactic-co-glycolic Acid) Nanoparticles
Authors: Barbero-Colmenar Elena , Guastaferro Mariangela , Baldino Lucia , Cardea Stefano , Reverchon Ernesto
Published: September 2022

This work proposes an improvement of the traditional electrospraying process, in which supercritical carbon dioxide (SC-CO2) is used to produce poly(lactic-co-glycolic acid) (PLGA) nanoparticles. The experiments were performed at different PLGA concentrations (1, 3 and 5% w/w), applied voltages (10 and 30 kV) and operating pressures (80, 120 and 140 bar). It was found that working at 140 bar and 30 kV, spherical nanoparticles, with mean diameters of 101 ± 13 nm and 151 ± 45 nm, were obtained, when solutions at 1% w/w and 3% w/w PLGA were electrosprayed, respectively. Increasing PLGA concentration up to 5% w/w, a mixture of fibers and particles was observed, indicating the transition to the electrospinning regime.
Alcohol Use among High School Learners in the Peri-Urban Areas, South Africa: A Descriptive Study on Accessibility, Motivations and Effects
Authors: Mathibe Mmampedi , Cele Lindiwe , Modjadji Perpetua
Published: September 2022

Learners are vulnerable to alcohol use and its negative effects, largely due to accessibility of alcohol products, especially in the localities with poor socioeconomic status and infrastructure. This study aimed to determine the accessibility, motivations and effects of alcohol use among high school learners (n = 403) in Tshwane North and West, South Africa, using a descriptive, cross-sectional design. Data were collected using a validated questionnaire and analysed using STATA 17. Learners (16 ± 2 years) had poor demographic status and lifestyle behaviors. Availability of alcohol outlets (54%) near schools was reported, and learners indicated easy access (65%) to taverns and bottle stores (30%), and purchasing alcohol without a proof of identity document (70%). Motivations for alcohol use were self-pleasure (36%), coping with stress (24%) and increasing self-esteem (19%). Almost half of the learners (49%) introduced themselves to alcohol use, while others were influenced by friends (36%) and family (14%). Reported alcohol related effects were a negative impact on health (56%), brain function (25%) and school work (12%), in addition to social harms, including problems with friends (25%) and parents (17%), physical fights (19%) and engaging in risky sexual behaviour (11%). Effective strategies are necessary to address underage alcohol use and should include regulating the proximity of alcohol outlets to schools, life skills training to address learners’ drinking motives and constantly alerting parents about the relevance of modeling behaviour.
Multi-Analytical Study on Excavated Human Bones in the Burial Environment at Shenna Ruins, Qinghai, China
Authors: Li Jiaxin , Zhang Ying , Chen Liang , Li Yuhu , Chao Xiaolian , Wang Juanli , Mai Bingjie , Cao Jing
Published: September 2022

Excavated human bones are important materials for revealing information about ancient human food, the ancient environment and the ancient climate, and the origins of ancient humans. Often, the chemical composition and biological characteristics of bones have changed to varying degrees, which means that they are contaminated and cannot be used for further analysis. Through research on the correlation between human bones excavated from a burial environment and their state of preservation, judging whether the excavated bones are contaminated is a prerequisite for scientific analysis, environmental archeology, and research on ancient human recipes. In this paper, human bones excavated from the Shenna ruins and the contamination of them in the burial environment has been judged using craniofacial measurement characteristics, pH measurement, scanning electron microscopy–energy dispersive spectrometer (SEM-EDS), X-ray diffraction (XRD), Fourier transform red external light spectrum (FTIR), and stable isotope tests (SIT). However, the organic compositions of the remains at Shenna are decomposed to a large degree, and the inorganic structure has been destroyed, which will eventually cause looseness and porosity, and the compositions of inorganic minerals in the human bones have not been changed or contaminated. The results indicate that the burial environment at Shenna accelerated the deterioration of human bones, but it has not affected the typical character of the human bone, and the human bones extracted can still be used for further trace element testing. Moreover, this can help to reduce the effort required to reveal information about ancient human food, as well as the need for further studies of the paleoenvironment and paleoclimate in the Shenna ruins.
Moisture Sorption of Wood Surfaces Modified by One-Sided Carbonization as an Alternative to Traditional Façade Coatings
Authors: Kymäläinen Maija , Dömény Jakub , Rautkari Lauri
Published: September 2022

Surface carbonization, or charring, of wooden cladding boards is a promising, low impact process that can substitute inorganic coatings. The char surface is inert and hydrophobic and possibly a long-lasting solution for exterior uses. To determine the performance of surface-charred wood, several sorption experiments were established. Sapwood of two hardwoods (aspen, birch) and two softwoods (pine, spruce) were used as the experimental material, modified by contact charring and gas flame charring, including surfaces coated with oil for further protection. The results showed that flame charring modification is equal to a double layer of acrylic paint on primer in terms of permeability on all wood species, with higher moisture exclusion efficiency at high relative humidity. Contact charring modification presented much improved properties in comparison to both flame charring and acrylic paint in all implemented sorption experiments, but the dimensional stability was poor with strong cupping in wetting. However, hardwoods and especially birch exhibited less dimensional distortion than the other investigated species, and oiling further reduced the cupping. The contact charring modification produced more repeatable results with less impact from substrate and all wood species benefitted, whereas the flame charring modification is more dependent on inherent properties of the wood species, and does not seem to suit aspen as well as birch, and pine as well as spruce, although oiling affected the observed results.
Evolution of Nanocrystalline Graphite’s Physical Properties during Film Formation
Authors: Gartner Mariuca , Anastasescu Mihai , Stroescu Hermine , Calderon-Moreno Jose Maria , Preda Silviu , Simionescu Octavian-Gabriel , Avram Andrei , Buiu Octavian
Published: September 2022

Nanocrystalline graphite (NCG) layers represent a good alternative to graphene for the development of various applications, using large area, complementary metal-oxide semiconductor (CMOS) compatible technologies. A comprehensive analysis of the physical properties of NCG layers—grown for different time periods via plasma-enhanced chemical vapour deposition (PECVD)—was conducted. The correlation between measured properties (thickness, optical constants, Raman response, electrical performance, and surface morphology) and growth time was established to further develop various functional structures. All thin films show an increased grain size and improved crystalline structure, with better electrical properties, as the plasma growth time is increased. Moreover, the spectroscopic ellipsometry investigations of their thickness and optical constants, together with the surface roughness extracted from the atomic force microscopy examinations and the electrical properties resulting from Hall measurements, point out the transition from nucleation to three-dimensional growth in the PECVD process around the five-minute mark.
Increase in Wear Resistance of Traction Wheel via Chromizing: A Study Combining Experiments and Simulations
Authors: Li Shanjun , Yang Zehua , Wan Qiang , Hou Jianfeng , Xiao Yangyi , Zhang Xin , Gao Rui , Meng Liang
Published: September 2022

The wear failure of traction wheels in orchard transport severely restricts the stability of orchard conveyors and impedes the mechanization of orchard work. In this study, the thermal-diffusion chromizing method was employed to increase the hardness of a traction wheel for the enhancement of wear resistance. The results show that a uniform and dense chrome coating with a thickness of 16 μm was formed on the surface. The coating was revealed to have a hardness of 1752.7 HV and benefited from the formation of Cr-C compounds. A friction test and a wear simulation test under both dry-friction and lubrication conditions were conducted to assess the enhanced wear resistance based on the friction coefficient and wear loss. The friction coefficient of QT400 and that of the chrome coating were 0.37 and 0.36, respectively, under dry conditions. Additionally, the friction coefficient of QT400 decreased to 0.12, while that of the chrome coating remained at 0.35, under lubrication conditions. In the wear simulation test, the wear loss of the chromed traction wheel was about 1/28 of that of the QT400 traction wheel under dry-friction conditions. In addition, the wear loss of the chromed traction wheel was about 1/24 of that of the QT400 traction wheel under lubrication conditions. Moreover, the wear mechanism was analyzed with a microstructure study and finite element analysis (FEA). The synergetic effect between fatigue wear and abrasive wear was likely responsible for the wear failure of the traction wheel. The method proposed in this study may be a promising way to enhance the wear resistance of QT400 traction wheels through the application of a chrome coating without sacrificing the loading capacity, and this work contributes to the understanding of the wear failure mechanism of traction wheels.
Numerical Simulation of Preheating Temperature on Molten Pool Dynamics in Laser Deep-Penetration Welding
Authors: Peng Jin , Liu Jigao , Yang Xiaohong , Ge Jianya , Han Peng , Wang Xingxing , Li Shuai , Wang Yongbiao
Published: September 2022

In this paper, a heat-flow coupling model of laser welding at preheating temperature was established by the FLUENT 19.0 software. The fluctuation of the keyhole wall and melt flow behavior in the molten pool under different preheating temperatures were analyzed, and the correlation between keyhole wall fluctuation and molten pool flow with spatters and bubbles was obtained. The results indicate that when the outer wall in the middle of the rear keyhole wall is convex, the inner wall is concave, which causes spatter or the bottom of the keyhole to collapse. When the metal layer in the middle of the rear keyhole wall turns into obliquely upward flow, welding spatter is generated. In contrast, the metal layer in the middle of the rear keyhole wall changes to flow into the keyhole, and the bottom of the keyhole collapses. When the preheating temperature is 300 K (ambient temperature), 400 K, and 500 K, the inner wall in the middle of the rear keyhole wall is concave. With the increase in the preheating temperature, the area of the concave gradually increases, and the size of the liquid column behind the keyhole opening gradually decreases. When the preheating temperature is 300 K, there are more spatters above the molten pool. In comparison, when the preheating temperature is 400 K or 500 K, there are less spatters, and the bottom of the keyhole collapses.
The Engineerization of Physical and Chemical Phenomena
Authors: Carotenuto Gianfranco
Published: September 2022

There are a number of concepts in materials science that are only ambiguously described in the literature and/or are not completely understood [...]
Microstructure Analysis of Al-7 wt% Si Alloy Solidified on Earth Compared to Similar Experiments in Microgravity
Authors: Roósz András , Rónaföldi Arnold , Li Yuze , Mangelinck-Noël Nathalie , Zimmermann Gerhard , Nguyen-Thi Henri , Svéda Mária , Veres Zsolt
Published: September 2022

During ground-based solidification, buoyancy flow can develop by the density difference in the hypoeutectic type of the alloys, such as Al-7 wt% Si alloy. Buoyancy flow can affect the thermal field, solute distribution in the melt, and the position and amount of the new grains. As solidification is a very complex process, it is not very easy to separate the different effects. Under microgravity conditions, natural convection does not exist or is strongly damped due to the absence of the buoyancy force. Therefore, experiments in microgravity conditions provide unique benchmark data for pure diffusive solidification conditions. Compared to the results of the ground-based and microgravity experiments, it is possible to get information on the effect of gravity (buoyancy force). In the framework of the CETSOL project, four microgravity solidification experiments were performed on grain refined (GF) and non-grain refined Al-7 wt% Si alloy onboard the International Space Station in the Materials Science Laboratory. These experiments aimed to study the effect of the solidification parameters (solid/liquid front velocity vSL, temperature gradient GSL) on the grain structure and dendritic microstructures. The microgravity environment eliminates the melt flow, which develops on Earth due to gravity. Four ground-based (GB) experiments were performed under Earth-like conditions with the same (similar) solidification parameters in a vertical Bridgman-type furnace having four heating zones. The detailed analysis of the grain structure, amount of eutectic, and secondary dendrite arm spacing (SDAS) for different process conditions is reported and compared with the results of the microgravity experiments. GB experiments showed that the microstructure was columnar in the samples that do not contain GF material or in case the solid/liquid (vSL front velocity was slow (0.02 mm/s)). In contrast, in the sample which contained GF material, progressive columnar/equiaxed transition (PCET) was observed at vSL = 0.077 mm/s and GSL = 3.9 K/mm. The secondary (SDAS) dendrite arm spacing follows the well-known power law, SDAS=K[t0]13, where K is a constant, and t0 is the local solidification time for both GB and µg experiments.
Microstructure and Wear Behavior of Laser Cladded CoCrNiMox Coatings on the Low Carbon Steel
Authors: Liu Ran , Dang Xianting , Peng Yating , Wu Tao
Published: September 2022

In this study, CoCrNiMox (x = 0, 1, 3 and 5, wt.%) alloy coatings were fabricated on the surface of low carbon steel by laser surface cladding. The scanning electron microscope (SEM), energy dispersive spectrometer (EDS), and X-ray diffraction (XRD) were used to analyze the microstructure and phases of the prepared coatings. The microhardness and wear resistance of these coating were also evaluated. The results showeded that a single-phase face-centered cubic (FCC) structure generated by the CoCrNi ternary compound in all the coatings, the σ phase, and the Mu (μ) phase, enriched with Cr and Mo and originated with additional Mo, exhibited a lamellar structure. The content of FCC single-phase structure in the coating gradually decreases with the increasing of Mo because the addition of Mo can promote the precipitation of the σ phase and the μ phase. Among all the laser cladded coatings, the CoCrNiMo5 alloy coating shows the best properties, owing to the higher proportion of intermetallic compounds in the σ phase and the μ phase, which can provide enhanced performance. This exhibited the narrowest wear scar width and showed the fatigue wear mechanism.
Artificial Intelligence for Crystal Growth and Characterization
Authors: Schimmel Saskia , Sun Wenhao , Dropka Natasha
Published: September 2022

The Special Issue on “Artificial Intelligence for Crystal Growth and Characterization” comprises six original articles in this emerging field of research [...]
X-ray Line Profile Analysis of Austenitic Phase Transition and Morphology of Nickel-Free Fe-18Cr-18Mn Steel Powder Synthesized by Mechanical Alloying
Authors: Romanczuk-Ruszuk Eliza , Nowik Krzysztof , Sztorch Bogna
Published: September 2022

In this study, microstructural evolution and phase transition of nickel-free Fe-18Cr-18Mn (wt. %) austenitic steel powders, induced by mechanical alloying, were investigated. X-ray diffraction, scanning electron microscopy, and microhardness testing techniques were used to observe the changes in the phase composition and particle size as functions of milling time. The first 30 h of mechanical alloying was performed in an argon atmosphere followed by nitrogen for up to 150 h. X-ray diffraction results revealed that the Fe-fcc phase started to form after 30 h of milling, and its fraction continued to increase with alloying time. However, even after 150 h of milling, weak Fe-bcc phase reflections were still detectable (~3.5 wt. %). Basic microstructure features of the multi-phase alloy were determined by X-ray profile analyses, using the whole powder pattern modeling approach to model anisotropic broadening of line profiles. It was demonstrated that the WPPM algorithm can be regarded as a powerful tool for characterizing microstructures even in more complicated multi-phase cases with overlapping reflections. Prolonging alloying time up to 150 h caused the evolution of the microstructure towards the nanocrystalline state with a mean domain size of 6 nm, accompanied by high densities of dislocations exceeding 1016/m2. Deformation-induced hardening was manifested macroscopically by a corresponding increase in microhardness to 1068 HV0.2. Additionally, diffraction data were processed by the modified Williamson–Hall method, which revealed similar trends of domain size evolutions, but yielded sizes twice as high compared to the WPPM method.
Impact of Mo-Doping on the Structural, Optical, and Electrocatalytic Degradation of ZnO Nanoparticles: Novel Approach
Authors: Ganesh Vanga , Hussien Mai S. A. , Shaik Ummar Pasha , Ade Ramesh , Mohammed Mervat I. , AlAbdulaal Thekrayat H. , Zahran Heba Y. , Yahia Ibrahim S. , Abdel-wahab Mohamed Sh.
Published: September 2022

Pure and Molybdenum (Mo)-doped zinc oxide (ZnO) nanoparticles were prepared by a cost-effective combustion synthesis route. XRD results revealed the decrement in crystallite size of ZnO with an increase in Mo-doping concentration. Optical bandgap (Eg) values were determined using optical reflectance spectra of these films measured in the range of 190–800 nm. The Eg values decreased with increasing the Mo-doping concentration. The dielectric properties of these samples were studied to determine the dielectric constant values. Raman spectra of these samples were recorded to know the structure. These sample absorption spectra were recorded for electrocatalytic applications. All the prepared samples were subjected to electrocatalytic degradation of Rhodamine B. The 0.01 wt% Mo doped ZnO showed 100% in 7 min electrocatalytic degradation.
The Art of Counseling in the Treatment of Head and Neck Cancer: Exploratory Investigation among Perceptions of Health Professionals in Southern Italy
Authors: Addeo Raffaele , Pompella Luca , Vitale Pasquale , Fattoruso Silvia Ileana Sara , Di Giovanni Ilaria , Perri Francesco , Caraglia Michele , Fasano Morena , Arigliani Raffaele
Published: September 2022

(1) Background: Recurrent and/or metastatic patients with head and neck squamous cell carcinoma show a poor prognosis, which has not changed significantly in 30 years. Preserving quality of life is a primary goal for this subset of patients; (2) Methods: A group of 19 physicians working in South Italy and daily involved in head and neck cancer care took an anonymous online survey aimed at revealing the level of knowledge and the application of communication techniques in daily patient care; (3) Results: Several specialists, 18 out 19 (95%), considered that patient participation in therapeutic choices is mandatory. The main obstacles to complete and reciprocate communication still consist of lack of time and staff, but also in the need for greater organization, which goes beyond the multidisciplinary strategy already used; (4) Conclusions: A greater impulse to training and updating on issues related to counseling can improve communication between the different clinicians involved in the treatment plan.
Factors Affecting the Cervical Cancer Screening Behaviors of Japanese Women in Their 20s and 30s Using a Health Belief Model: A Cross-Sectional Study
Authors: Cui Zhengai , Kawasaki Hiromi , Tsunematsu Miwako , Cui Yingai , Kakehashi Masayuki
Published: September 2022

In recent years, the incidence and mortality rates of cervical cancer (CC) have increased among young women. Cervical cancer screening (CCS) is crucial to reducing the incidence and mortality of CC in a country such as Japan, where it is challenging to raise HPV vaccination rates. The purpose of this study was to identify psychological and personal characteristics relating to CCS participation among young people by using the Health Belief Model (HBM). For this cross-sectional study, an internet survey was conducted between February–March 2018. Based on HBM and personal characteristics, χ2 tests and logistic analyses were used to identify factors influencing CCS. Responses obtained from 816 women in their 20s and 30s were used in the analysis. For HBM-based psychological characteristics, the odds ratios were significantly higher for “cues to participation in screening” and “barriers to participation at the time of cancer screening”, while “barriers to participation before cancer screening” showed significantly lower odds ratios. On the other hand, it was found that the presence of children and having regular health checkups affected the attributes of screening that were significant for decision-making. Therefore, it is important to create proactive measures to encourage younger women to undergo medical examinations.
Efficacy of Immunotherapy Combined with Antiangiogenic Therapy in Treatment-Failure Patients with Advanced Carcinoma Ex Pleomorphic Adenoma of the Submandibular Gland: A Case Report
Authors: Sa Huanlan , Xu Yinghui , Ma Xiaobo , Wang Xu , Sun Chao , Qiu Shi , Guo Ye , Yang Zhiguang , Liu Yunpeng , Ma Kewei
Published: September 2022

Carcinoma ex pleomorphic adenoma (Ca ex PA) is a rare malignant tumor that arises from a primary or recurrent benign pleomorphic adenoma (PA). Ca ex PA has an aggressive behavior and poor prognosis. To date, there are no standardized therapeutic methods. Herein, we reported a case of a 57-year-old Chinese female with Ca ex PA of the submandibular gland. After surgery, cervical lymph nodes recurred, and multiple distant metastases were detected. During the treatment, she received multiple chemotherapies and radiotherapy but suffered from multidrug resistance and repeated disease progression. Hence, PD-1 inhibitor (sintilimab), in combination with anlotinib, was administered, which resulted in better control of pulmonary metastases compared to the other treatment regimens. This provided an alternative treatment option for Ca ex PA of the submandibular gland patients with failed multiple therapies.
Biodiversity and Conservation of Vascular Flora: A Challenge for the Survival of Humans on Earth
Authors: Stinca Adriano
Published: September 2022

In the current state of knowledge, the Earth is the only planet to host life and, therefore, to be covered by plants [...]
Learnings and Benefits from Co-Researching: Views of Advisors with Intellectual Disabilities
Authors: Diaz-Garolera Gemma , Fullana Judit , Pallisera Maria , Puyaltó Carolina , Rey Ana , Beltran Maialen
Published: September 2022

The Convention on the Rights of Persons with Disabilities recognizes the value of the contributions these individuals can make to well-being and diversity, and thus the active role they must play in research on their lives. This study aims to investigate the perspectives of people with intellectual disabilities who were part of an Advisory Committee that has been collaborating in research for 9 years on what they learnt and what the research experience meant to them. Their opinions were analysed through individual interviews, focus groups, and the revision of more than 297 written and visual documents produced during the last 9 years. Participants reported significant learning related to the research process, as well as socio-personal learning. Moreover, they reported the increase of their sense of belonging to a socially valued group, enrichment of their social networks and a gain in personal well-being. Beyond contributing to the conduction of research based on the people’s needs, the involvement of people with intellectual disabilities in dissemination actions addressed to the professional field and social policies is deemed as a necessary action in order to make their role in social change more visible.
Detection of White Leaf Disease in Sugarcane Using Machine Learning Techniques over UAV Multispectral Images
Authors: Narmilan Amarasingam , Gonzalez Felipe , Salgadoe Arachchige , Powell Kevin
Published: September 2022

Sugarcane white leaf phytoplasma (white leaf disease) in sugarcane crops is caused by a phytoplasma transmitted by leafhopper vectors. White leaf disease (WLD) occurs predominantly in some Asian countries and is a devastating global threat to sugarcane industries, especially Sri Lanka. Therefore, a feasible and an effective approach to precisely monitoring WLD infection is important, especially at the early pre-visual stage. This work presents the first approach on the preliminary detection of sugarcane WLD by using high-resolution multispectral sensors mounted on small unmanned aerial vehicles (UAVs) and supervised machine learning classifiers. The detection pipeline discussed in this paper was validated in a sugarcane field located in Gal-Oya Plantation, Hingurana, Sri Lanka. The pixelwise segmented samples were classified as ground, shadow, healthy plant, early symptom, and severe symptom. Four ML algorithms, namely XGBoost (XGB), random forest (RF), decision tree (DT), and K-nearest neighbors (KNN), were implemented along with different python libraries, vegetation indices (VIs), and five spectral bands to detect the WLD in the sugarcane field. The accuracy rate of 94% was attained in the XGB, RF, and KNN to detect WLD in the field. The top three vegetation indices (VIs) for separating healthy and infected sugarcane crops are modified soil-adjusted vegetation index (MSAVI), normalized difference vegetation index (NDVI), and excess green (ExG) in XGB, RF, and DT, while the best spectral band is red in XGB and RF and green in DT. The results revealed that this technology provides a dependable, more direct, cost-effective, and quick method for detecting WLD.
Stochastic Thermodynamics of an Electromagnetic Energy Harvester
Authors: Costanzo Luigi , Lo Schiavo Alessandro , Sarracino Alessandro , Vitelli Massimo
Published: September 2022

We study the power extracted by an electromagnetic energy harvester driven by broadband vibrations. We describe the system with a linear model, featuring an underdamped stochastic differential equation for an effective mass in a harmonic potential, coupled electromechanically with the current in the circuit. We compare the characteristic curve (power vs. load resistance) obtained in experiments for several values of the vibration amplitude with the analytical results computed from the model. Then, we focus on a more refined analysis, taking into account the temporal correlations of the current signal and the fluctuations of the extracted power over finite times. We find a very good agreement between the analytical predictions and the experimental data, showing that the linear model with effective parameters can describe the real system, even at the fine level of fluctuations. Our results could be useful in the framework of stochastic thermodynamics applied to energy harvesting systems.
Elliptic Flowers: New Types of Dynamics to Study Classical and Quantum Chaos
Authors: Attarchi Hassan , Bunimovich Leonid A.
Published: September 2022

We construct examples of billiards where two chaotic flows are moving in opposite directions around a non-chaotic core or vice versa; the dynamics in the core are chaotic but flows that are moving in opposite directions around it are non-chaotic. These examples belong to a new class of dynamical systems called elliptic flowers billiards. Such systems demonstrate a variety of new behaviors which have never been observed or predicted to exist. Elliptic flowers billiards, where a chaotic (non-chaotic) core coexists with the same (chaotic/non-chaotic) type of dynamics in flows were recently constructed. Therefore, all four possible types of coexisting dynamics in the core and tracks are detected. However, it is just the beginning of studies of elliptic flowers billiards, which have already extended the imagination of what may happen in phase spaces of nonlinear systems. We outline some further directions of investigation of elliptic flowers billiards, which may bring new insights into our understanding of classical and quantum dynamics in nonlinear systems.
Tariff Menus to Avoid Rebound Peaks: Results from a Discrete Choice Experiment with Swiss Customers
Authors: Ludwig Patrick , Winzer Christian
Published: September 2022

While automation helps to increase load-shifting, the combination of automation with time-of-use (TOU) or critical-peak prices (CPP) may lead to rebound peaks at the beginning of low-tariff periods which may exceed the original peak. Using a discrete choice experiment with a representative sample of 696 Swiss consumers, we find that a tariff menu including (i) a flat price with direct load control (DLC) and (ii) a time-of-use tariff without direct load control could avoid this problem. The majority (57%) of mostly younger customers, which could be interested in automation would likely sign up for a DLC with flat prices, while the remaining customers would either chose a TOU tariff with manual load control (28%) or avoid any form of load-shifting incentives (15%).
Closed-Loop Agricultural Production and Its Environmental Efficiency: A Case Study of Sheep Wool Production in Northwestern Kyrgyzstan
Authors: Komorowska Monika , Niemiec Marcin , Sikora Jakub , Szeląg-Sikora Anna , Gródek-Szostak Zofia , Findura Pavol , Gurgulu Hatice , Stuglik Joanna , Chowaniak Maciej , Atılgan Atılgan
Published: September 2022

As a country with not only significant production potential but also fragmented land ownership, the Kyrgyz Republic struggles with environmental efficiency, which is a strategic element of environmental management in agricultural production. The objective of this study was to assess the environmental efficiency of sheep’s wool when used as a fertilizer in bean production in northern Kyrgyzstan. In this study, the efficiency indicator was taken to be GHG emissions per functional unit of product, using a proprietary methodology for calculating GHG emissions to determine the true value of this material as a source of soil nutrients and organic matter. Two experimental factors were used in the experiment: fertilizer type and fertilizer rate. Fertilization with sheep wool resulted in a 15% higher bean yield compared to when fertilized with mineral fertilizers at a comparable rate, converted to pure nitrogen. By using sheep wool as a source of mineral nutrients for the plants, the carbon footprint was reduced by almost 10% compared to a facility with mineral fertilization. Therefore, the use of sheep wool as a source of plant nutrients is environmentally justified.
Research on the Topology and Control Strategy of a Novel Three-Port Converter
Authors: Wang Tao , Chen Xiangqian , Guo Qiang , Li Shan
Published: September 2022

A novel three-port converter (TPC) is proposed to meet the diversity of demand for electrical equipment in this paper. It interfaces a single input power port and two output ports. The proposed TPC can be viewed as two bidirectional DC-DC converters. With a different operation mode, the proposed TPC can output two DC voltages or a single DC and a single AC voltage. The topology and operation principal of the TPC is analyzed in detail. Moreover, the mathematic model of the TPC is derived. Then, by considering the dynamic response and disturbance suppression, a step by step PI and PR controller design process for TPC is also presented. Both the simulation and the experimental results validate the proposed method.
Uncertainty Assessment of Corrected Bottom-Hole Temperatures Based on Monte Carlo Techniques
Authors: Schölderle Felix , Götzl Gregor , Einsiedl Florian , Zosseder Kai
Published: September 2022

Most temperature predictions for deep geothermal applications rely on correcting bottom-hole temperatures (BHTs) to undisturbed or static formation temperatures (SFTs). The data used for BHT correction are usually of low quality due to a lack of information and poor documentation, and the uncertainty of the corrected SFT is therefore unknown. It is supposed that the error within the input data exceeds the error due to the uncertainty of the different correction schemes. To verify this, we combined a global sensitivity study with Sobol indices of six easy-to-use conventional correction schemes of the BHT data set of the Bavarian Molasse Basin with an uncertainty study and developed a workflow that aims at presenting a valid error range of the corrected SFTs depending on the quality of their input data. The results give an indication of which of the investigated correction methods should be used depending on the input data, as well as show that the unknown error in the input parameters exceeds the error of the individual BHT correction methods as such. The developed a priori uncertainty-based BHT correction helps to provide a real estimate of the subsurface temperatures needed for geothermal prospecting and probabilistic risk assessment.
Experimental Study on Effects of RCSL and RCTL Combustion Chamber for Combustion Process of Highly Intensified Diesel Engine
Authors: Wen Ming , Li Yufeng , Zhu Weiqing , Cao Rulou , Sun Kai
Published: September 2022

In order to optimize the combustion chamber of a highly intensified single-cylinder diesel engine, including improvement of the air utilization rate in the combustion chamber, optimization of the fuel/air mixture process, reduction of the soot emission in the cylinder, and obtainment of the optimal combustion performance parameters, a re-entrant combustion chamber with step-typed lip (RCSL) and a re-entrant combustion chamber with tilted lip (RCTL) were innovatively designed and the effects of the throat diameter on the combustion process was obtained through experiments. When the RCSL with a diameter of 72 mm worked, target for the Brake Mean Effective Pressure (BMEP) of 2.6 MPa could be achieved under the condition of excess air coefficient of 1.5~1.7. At the same time, this had the advantages of lower fuel consumption, lower exhaust temperature, lower smoke level, and shorter combustion duration. Under the same BMEP, the RCTL had lower fuel consumption, exhaust gas temperature and maximum combustion pressure, as well as faster heat release rate (HRR) and shorter combustion duration than the RCSL.
Uniformity of Supply Air in the Plenum for Under-Floor Air Distribution Ventilation in a Circular Conference Room: A CFD Study
Authors: Fan Xiaolei , Yu Tao , Liu Peng , Li Xiangdong
Published: September 2022

Underfloor air distribution (UFAD) systems are increasingly used for their advantages in improving energy savings, indoor air quality, and thermal comfort. In UFAD systems, an underfloor plenum delivers conditioned air to the air supply diffusers. The distribution of internal air velocity and static pressure in plenums determines the uniformity of the airflow to the occupied zones. As a result, the plenum has a detrimental effect on the characteristics of the supply air and, thus, the resulting indoor air quality and thermal comfort. Nevertheless, most existing studies on underfloor plenums focused on small-scale plenums with a single internal air duct. Large plenums and multiple air ducts in UFAD equipped in large premises are underexplored. In this study, a circular underfloor plenum with a large scale (radius of 15 m, height difference of 0.9−2.9 m) and 503 under-seat diffusers in a conference room was studied using computational fluid dynamics (CFD) simulation (ANSYS Fluent (16.0)). The distributions of airflow velocity and static pressure inside the plenum were analyzed and compared to one concentrated air supply mode and three uniform air supply modes. Based on the air velocity at the center of under-seat diffusers, the outgoing airflow uniformity from the diffusers under four cases was evaluated by the index of air velocity uniformity. The results showed that the multiple supply ducts with bottom air outlets yielded the best uniformity of supply air. The findings of this paper are expected to provide a technical basis for realizing the optimal design of the UFAD system in terms of uniformity of supply air.
Abnormal Data Cleaning Method for Wind Turbines Based on Constrained Curve Fitting
Authors: Yin Xiangqing , Liu Yi , Yang Li , Gao Wenchao
Published: September 2022

With the increase of the scale of wind turbines, the problem of data quality of wind turbines has become increasingly prominent, which seriously affects the follow-up research. A large number of abnormal data exist in the historical data recorded by the wind turbine Supervisory Control And Data Acquisition (SCADA) system. In order to improve data quality, it is necessary to clean a large number of abnormal data in the original data. Aiming at the problem that the cleaning effect is not good in the presence of a large number of abnormal data, a method for cleaning abnormal data of wind turbines based on constrained curve fitting is proposed. According to the wind speed-power characteristics of wind turbines, the constrained wind speed-power curve is fit with the least square method, and the constrained optimization problem is transformed into an unconstrained optimization problem by using the external penalty function method. Data cleaning was performed on the fitted curve using an improved 3-σ standard deviation. Experiments show that, compared with the existing methods, this method can still perform data cleaning well when the historical wind turbine data contains many abnormal data, and the method is insensitive to parameters, simple in the calculation, and easy to automate.
Enabling Technologies for Energy Communities: Some Experimental Use Cases
Authors: Menniti Daniele , Pinnarelli Anna , Sorrentino Nicola , Vizza Pasquale , Barone Giuseppe , Brusco Giovanni , Mendicino Stefano , Mendicino Luca , Polizzi Gaetano
Published: September 2022

It is known that the energy transition can be achieved not only with the use of renewable energy sources but also with a new conception and management of the electricity system. Renewable energy communities are then introduced as organizations for maximizing the self-consumption of energy produced from renewable energy sources. To ensure that these energy communities can operate, there is a need for enabling technologies that allow for monitoring, data and algorithms processing as well as the enabling of the same algorithms. There exists a huge confusion in the actual technologies useful to implement the energy communities. This paper first describes and groups the main enabling technologies, analyzing the services that can be offered. The scope is to emphasize the importance of having accurate, efficient and effective technologies that allow the implementation of such communities, underlining how such technologies interact with each other. Using such technologies is important to observing the possible technical and energetic results; indeed, use cases concerning the use of these enabling technologies are proposed and analyzed, showing their operating and their good environmental and energy impact.
Sensitivity Analysis, Uncertainty Quantification and Predictive Modeling of Nuclear Energy Systems
Authors: Cacuci Dan Gabriel
Published: September 2022

The Special Issue “Sensitivity Analysis, Uncertainty Quantification and Predictive Modeling of Nuclear Energy Systems” comprises nine articles that present important applications of concepts for performing sensitivity analyses and uncertainty quantifications of models of nuclear energy systems [...]
An Overview of Waste Gasification and Syngas Upgrading Processes
Authors: Segneri Valentina , Ferrasse Jean Henry , Trinca Antonio , Vilardi Giorgio
Published: September 2022

The increasing attention towards climate change and greenhouse gas emissions makes the exploitation of renewable energy sources one of the key pathways for sustainable power generation or chemical production [...]
Mismatch Repair Deficiency and Microsatellite Instability
Authors: Schöniger Sandra , Rüschoff Josef
Published: September 2022

Mismatch repair deficiency (MMRd) is caused by the biallelic inactivation of an MMR gene, which can be attributed either to an inherited or an acquired pathway. MMRd is characterized by the inability of cells to repair spontaneous mutations in microsatellites that occur during replication. Microsatellites are repetitive nucleotide sequences composed of one to six base pairs. Mutations in microsatellites lead to deletions or insertions of sequence units that are designated as microsatellite instability (MSI). MMRd is diagnosed by immunochemistry and is characterized by loss of nuclear immunostaining for at least one of the four MMR proteins that are routinely examined, i.e., MSH2, MSH6, MLH1 and PMS2. Available tests for MSI are PCR and next generation sequencing. MMRd and MSI predispose to tumor initiation and progression, increase tumor mutational burden as well as tumor immunogenicity, facilitate the activation of the programmed cell death protein 1/programmed cell death ligand 1 (PD-1/PD-L1) immune checkpoint pathway and serve as prognostic and predictive biomarkers in solid tumors.
Effects of Biological and Chemical Degradation on the Properties of Scots Pine—Part II: Wood-Moisture Relations and Viscoelastic Behaviour
Authors: Broda Magdalena , Spear Morwenna J. , Curling Simon F. , Dimitriou Athanasios
Published: September 2022

The present research aimed to assess the moisture properties and viscoelastic behaviour of artificially degraded pine wood, intended to serve as a model material for ongoing studies on new conservation treatments for waterlogged archaeological wood. Sorption isotherms and hydroxyl accessibility were measured using a Dynamic Vapour Sorption (DVS) system, while the investigation of the selected wood rheological properties was performed using Dynamic Mechanical Analysis (DMA). Fungal decomposition of pine by Coniophora puteana decreased the maximum equilibrium moisture content (EMC) from 20.3% to 17.7% in the first and from 19.9% to 17.1% in the second DVS run compared to undegraded pine, while chemical degradation using 50% NaOH solution increased the wood EMC to 24.6% in the first and 24.2% in the second run. The number of free hydroxyls measured for the biologically degraded sample was similar to sound wood, while chemical degradation reduced their number from 11.3 mmol g−1 to 7.9 mmol g−1. The alterations in the wood chemical composition due to different degradation processes translated into changes in viscoelastic behaviour. For biologically degraded wood, a reduction in the loss modulus and storage modulus at the temperature of 25 °C was observed compared to undegraded pine. Surprisingly, for chemically degraded pine, the values were more similar to sound wood due to the considerable densification of the material resulting from shrinkage during drying. The loss factor values for both degraded wood types were higher than for undegraded ones, indicating an increase in damping properties compared to sound pine. Distinct changes were visible in the storage modulus and loss factor graphs for DMA of chemically and biologically degraded pine. The degradation processes used in the study produced wood types with different moisture and viscoelastic properties. However, both seem useful as model materials in the research on the new conservation agents for waterlogged archaeological wood.
Assessment of Wound Recovery and Radial Growth 10 Years after Forest Operations in Hardwood Stands
Authors: Tavankar Farzam , Ezzati Sättar , Latterini Francesco , Lo Monaco Angela , Venanzi Rachele , Picchio Rodolfo
Published: September 2022

Damage to the residual stand caused by forest operations can have detrimental impacts on the biological processes of stand growth. This study shows the details from monitoring damages related to manual motor ground-based timber operations in a mountain mixed hardwood forest. The harvesting system was cut-to-length, and logs were extracted by wheeled cable-skidders. Data were collected from the remaining trees immediately after logging and 10 years after the logging session. The parameters assessed included stem injury, radial growth increment and wound healing rate for five hardwood species of commercial interest. The number of injured trees represented 15% of the residual stand, 23% of the wounds were related to the felling operation and 76% to extraction. Wound height, wound size and damage to bark, due to felling, were larger than those in extraction, while wound width and damages to cambium and wood caused by extraction were larger than those triggered by felling. Ten years after harvesting, average longitudinal and radial growth increments were reduced by 38% and 24%, respectively. Wound healing rates ranged from 12.90 mm yr−1 for extraction wounds to 19.70 mm yr−1 for felling ones within 10 years. On average 73% of all wounds were still unrecovered and 17% of these were decayed, while only 10% were fully healed within a 10-year recovery period. The analysis showed that the best recovering performance among damaged trees was mostly achieved in shade-intolerant species with a diameter less than 40 cm, located in the dominant canopy layer with a wound size smaller than 100 cm2. In addition to the significant effect on log quality, the ecological longevity of residual trees has major implications for pre-planning harvesting operations that can preserve the quality and value of residual trees. Understanding the damage inflicted upon residual trees is essential to reduce economic losses, improve planning of harvest operations and, ultimately, ensure a sustainable harvest of mixed hardwood stands in mountain regions.