bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis, Thermal Behavior, and Mechanical Properties of Fully Biobased Poly(Hexamethylene 2,5-Furandicarboxylate-Co-Sebacate) Copolyesters
Authors: Feng Shiwei , Jiang Zhiguo , Qiu Zhaobin
Published: December 2022

In this research, three fully biobased poly(hexamethylene 2,5-furandicarboxylate-co-sebacate) (PHFSe) copolyesters with low contents of hexamethylene sebacate (HSe) unit (10 mol%, 20 mol%, and 30 mol%) were successfully synthesized through a two-step transesterification/esterification and polycondensation method. The chemical structure and actual composition of PHFSe copolyesters were confirmed by hydrogen nuclear magnetic resonance. The thermal behavior and mechanical property of PHFSe copolyesters were investigated and compared with those of the poly(hexamethylene 2,5-furandicarboxylate) (PHF) homopolymer. Both PHFSe copolyesters and PHF showed the high thermal stability. The basic thermal parameters, including glass transition temperature, melting temperature, and equilibrium melting temperature, gradually decreased with increasing the HSe unit content. PHFSe copolyesters crystallized more slowly than PHF under both the nonisothermal and isothermal melt crystallization conditions; however, they crystallized through the same crystallization mechanism and crystal structure. In addition, the mechanical property, especially the elongation at break of PHFSe copolyesters, was obviously improved when the HSe unit content was greater than 10 mol%. In brief, the thermal and mechanical properties of PHF may be easily tuned by changing the HSe unit content to meet various practical end-use requirements.
Optical Penetration and “Fingerprinting” Analysis of Automotive Optical Liquid Silicone Components Based on Wavelet Analysis and Multiple Recognizable Performance Evaluation
Authors: Chang Hanjui , Lu Shuzhou , Sun Yue , Zhang Guangyi , Rao Longshi
Published: December 2022

The residual stress phenomenon in the injection process of an optical lens affects the quality of optical components, and the refractive error caused by geometric errors is the most serious, followed by the degradation of the accuracy and function of optical components. It is very important to ensure that the lens geometry remains intact and the refractive index is low. Therefore, a parameter design method for an optical liquid silicon injection molding was proposed in this study. Wavelet analysis was applied to the noise reduction and feature extraction of the cavity pressure/pressure retaining curve of the injection molding machine, and multiple identifiable performance evaluation methods were used to identify and optimize the parameters of the molding process. Taking an automotive LED lens as an example, Moldex3D simulation software was used to simulate the molding of an LED lens made of LSR material, and two key injection molding factors, melt temperature and V/P switching point, were analyzed and optimized. In this paper, the transmittance and volume shrinkage of LED lenses are taken as quality indexes, and parameters are optimized by setting different V/P switching points and melt temperature schemes. The experimental results show that the residual stress is negatively correlated with transmittance, and the higher the residual stress, the lower the transmittance. Under the optimum process parameters generated by this method, the residual stress of plastic parts is significantly optimized, and the optimization rate is above 15%. In addition, when the V/P switching point is 98 and the melt temperature is 30 °C, the product quality is the best, the volume shrinkage rate is the smallest, and the size is 2.895%, which also means that the carbon emissions are the lowest.
Polymerization of Hexene-1 and Propylene over Supported Titanium–Magnesium Catalyst: Comparative Data on the Polymerization Kinetics and Molecular Weight Characteristics of Polymers
Authors: Matsko Mikhail , Echevskaya Ludmila , Zakharov Vladimir
Published: December 2022

Data are presented on the great differences of the kinetics of hexene-1 and propylene polymerization over the same supported titanium–magnesium catalyst, as well as molecular weight and molecular weight distribution of the polymers produced. It is found that the composition of cocatalysts (AlEt3 or Al(i-Bu)3 greatly affects the kinetics of hexene-1 polymerization and molecular weight distribution of polyhexene, contrary to data obtained at propylene polymerization. The presence of hydrogen at hexene-1 polymerization leads to a much higher increase of activity in comparison with propylene polymerization. Possible reasons for these differences are discussed on the basis of experimental results.
Synthesis of Methacryloylated Hydroxyethylcellulose and Development of Mucoadhesive Wafers for Buccal Drug Delivery
Authors: Buang Fhataheya , Chatzifragkou Afroditi , Amin Mohd Cairul Iqbal Mohd , Khutoryanskiy Vitaliy V.
Published: December 2022

Non-ionic hydroxyethylcellulose (HEC) has limited mucoadhesive properties for application in transmucosal drug delivery. In this study, HEC was chemically modified by reaction with glycidyl methacrylate. This allowed introducing the methacryloyl groups to HEC structure to make it capable of forming covalent bonds with the sulfhydryl groups present in the mucin glycoprotein to achieve enhanced mucoadhesive properties. The results showed a successful modification of HEC as confirmed by 1H NMR and FTIR spectroscopies. The quantification of methacryloyl moieties was conducted using HPLC. The toxicity studies using in vivo planaria acute toxicity assay, in vivo planaria fluorescent test, and in vitro MTT assay with Caco-2 cell line confirmed that the chemical modification of HEC does not result in any toxicological effects. Mucoadhesive wafers were developed based on parent and modified HEC as a model dosage form for buccal delivery. The mucoadhesive properties of modified HEC assessed using a tensile test were found to be significantly better compared to unmodified HEC.
Morphological, Mechanical, and Antimicrobial Properties of PBAT/Poly(methyl methacrylate-co-maleic anhydride)–SiO2 Composite Films for Food Packaging Applications
Authors: Venkatesan Raja , Alagumalai Krishnapandi , Raorane Chaitany Jayprakash , Raj Vinit , Shastri Divya , Kim Seong-Cheol
Published: December 2022

A poly(methyl methacrylate-co-maleic anhydride) P(MMA-co-MA) copolymer was synthesized via radical polymerization. The synthesized P(MMA-co-MA) copolymer was identified by 1H- and 13C-nuclear magnetic resonance spectroscopy (1H-NMR), (13C-NMR), Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The poly(butylene adipate-co-terephthalate) (PBAT)/P(MMA-co-MA)–SiO2 composites were developed using a solution-casting method. The PBAT to P(MMA-co-MA) weight ratio was kept at 70:30, while the weight percentage of SiO2 nanoparticles (NPs) was varied from 0.0 to 5.0 wt.%. SiO2 was used for PBAT/P(MMA-co-MA) to solve the compatibility between PBAT and the P(MMA-co-MA) matrix. The PBAT/P(MMA-co-MA)–SiO2 composites were characterized by studied FTIR spectroscopy, XRD, SEM, and TEM. A comparison of the composite film PBAT/P(MMA-co-MA)–SiO2 (PBMS-3) with the virgin PBAT and P(MMA-co-MA) film revealed its good tensile strength (19.81 MPa). The WVTR and OTR for the PBAT/P(MMA-co-MA)–SiO2 composites were much smaller than for PBAT/P(MMA-co-MA). The PBAT/P(MMA-co-MA)–SiO2 WVTR and OTR values of the composites were 318.9 ± 2.0 (cc m−2 per 24 h) and 26.3 ± 2.5 (g m−2 per 24 h). The hydrophobicity of the PBAT/P(MMA-co-MA) blend and PBAT/P(MMA-co-MA)–SiO2 composites was strengthened by the introduction of SiO2, as measured by the water contact angle. The PBAT/P(MMA-co-MA)–SiO2 composite films showed excellent antimicrobial activity against the food-pathogenic bacteria E. coli and S. aureus from the area of inhibition. Overall, the improved packaging characteristics, such as flexibility, tensile strength, low O2 and H2O transmission rate, and good antimicrobial activities, give the PBAT/P(MMA-co-MA)–SiO2 composite film potential for use in food packaging applications.
Aminosilane-Functionalized Zeolite Y in Pebax Mixed Matrix Hollow Fiber Membranes for CO2/CH4 Separation
Authors: Lu Soon-Chien , Wichidit Thakorn , Narkkun Thanitporn , Tung Kuo-Lun , Faungnawakij Kajornsak , Klaysom Chalida
Published: December 2022

Due to their interfacial defects between inorganic fillers and polymer matrices, research into mixed matrix membranes (MMMs) is challenging. In the application of CO2 separation, these defects can potentially jeopardize the performance of membranes. In this study, aminosilane functionalization is employed to improve the nano-sized zeolite Y (ZeY) particle dispersion and adhesion in polyether block amide (Pebax). The performance of CO2/CH4 separation of Pebax mixed matrix composite hollow fiber membranes, incorporated with ZeY and aminosilane-modified zeolite Y (Mo-ZeY), is investigated. The addition of the zeolite filler at a small loading at 5 wt.% has a positive impact on both gas permeability and separation factor. Due to the CO2-facilitated transport effect, the performance of MMMs is further improved by the amino-functional groups modified on the ZeY. When 5 wt.% of Mo-ZeY is incorporated, the gas permeability and CO2/CH4 separation factor of the Pebax membrane are enhanced by over 100% and 35%, respectively.
The Use of Polymers to Enhance Post-Orthodontic Tooth Stability
Authors: Rosyida Niswati Fathmah , Ana Ika Dewi , Alhasyimi Ananto Ali
Published: December 2022

Relapse after orthodontic treatment occurs at a rate of about 70 to 90%, and this phenomenon is an orthodontic issue that has not yet been resolved. Retention devices are one attempt at prevention, but they require a considerable amount of time. Most orthodontists continue to find it challenging to manage orthodontic relapse; therefore, additional research is required. In line with existing knowledge regarding the biological basis of relapse, biomedical engineering approaches to relapse regulation show promise. With so many possible uses in biomedical engineering, polymeric materials have long been at the forefront of the materials world. Orthodontics is an emerging field, and scientists are paying a great deal of attention to polymers because of their potential applications in this area. In recent years, the controlled release of bisphosphonate risedronate using a topically applied gelatin hydrogel has been demonstrated to be effective in reducing relapse. Simvastatin encapsulation in exosomes generated from periodontal ligament stem cells can promote simvastatin solubility and increase the inhibitory action of orthodontic relapse. Moreover, the local injection of epigallocatechin gallate-modified gelatin suppresses osteoclastogenesis and could be developed as a novel treatment method to modify tooth movement and inhibit orthodontic relapse. Furthermore, the intrasulcular administration of hydrogel carbonated hydroxyapatite-incorporated advanced platelet-rich fibrin has been shown to minimize orthodontic relapse. The objective of this review was to provide an overview of the use of polymer materials to reduce post-orthodontic relapse. We assume that bone remodeling is a crucial factor even though the exact process by which orthodontic correction is lost after retention is not fully known. Delivery of a polymer containing elements that altered osteoclast activity inhibited osteoclastogenesis and blocking orthodontic relapse. The most promising polymeric materials and their potential orthodontic uses for the prevention of orthodontic relapse are also discussed.
Improvement of the Thermal Stability of Polymer Bioblends by Means of Reactive Extrusion
Authors: Carrasco Félix , Santana Pérez Orlando , León Albiter Noel , Maspoch Maria Lluïsa
Published: December 2022

Poly(lactic acid) (PLA) and biosourced polyamide (PA) bioblends, with a variable PA weight content of 10–50%, were manufactured by melt blending in order to improve the behavior of PLA against thermal degradation. The effect of reactive extrusion on the thermal performance of PLA within bioblends was analyzed. The reactive extrusion was made by means of the addition of a styrene-acrylic multi-functional-epoxide oligomeric reactive agent (SAmfE), with the commercial name of Joncryl. Four parameters were considered in order to study the thermal behavior of bioblends against thermal decomposition: the onset decomposition temperature, the shape and temperature interval of the thermal decomposition patterns, the activation energy of the thermal decomposition, and the evidence leading to the most probable mechanism. The latter was determined by means of three evidence: standardized conversion functions, y(α) master plots, and integral mean error. It was shown that reactive extrusion of PLA as well as PA incorporation to the polymer matrix of PLA were responsible for an increase in the onset decomposition temperature of 10.4 °C. The general analytical equation (GAE) was used to evaluate the kinetic parameters of the thermal degradation of PLA within bioblends for various reaction mechanisms. It was shown that the random scission of macromolecular chains is the best mechanism for both untreated and treated PLA by means of reactive extrusion. It was shown that reactive extrusion together with higher content of PA resulted in an increased protective effect against the thermal degradation of PLA as demonstrated by an increase in activation energy of 60 kJ/mol. It was found that there is a relationship between the increase in activation energy and the increase in the onset decomposition temperature when using reactive extrusion. The improvement of the thermal stability of bioblends by means of reactive extrusion was explained by an increase in the complex viscosity from 980 to 2000 Pa·s at 0.06 rad/s and from 250 to 300 Pa·s at 630 rad/s for bioblend containing 30% of PLAREX and by a finer dispersion of PA within the PLAREX matrix. Results from DSC were not conclusive regarding the compatibility between both phases.
Cadmium Sulfide—Reinforced Double-Shell Microencapsulated Phase Change Materials for Advanced Thermal Energy Storage
Authors: Zhang Shendao , Zhu Yucao , Zhang Huanzhi , Xu Fen , Sun Lixian , Xia Yongpeng , Lin Xiangcheng , Peng Hongliang , Ma Lei , Li Bin , Yan Erhu , Huang Pengru
Published: December 2022

Phase change materials (PCMs) are widely used to improve energy utilization efficiency due to their high energy storage capacity. In this study, double-shell microencapsulated PCMs were constructed to resolve the liquid leakage issue and low thermal conductivity of organic PCMs, which also possess high thermal stability and multifunctionality. We used assembly to construct an inorganic–organic double shell for microencapsulate PCMs, which possessed the unprecedented synergetic properties of a cadmium sulfide (CdS) shell and melamine–formaldehyde polymeric shell. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images confirmed the well-designed double-shell structure of the microcapsules, and the CdS was successfully assembled as the second shell on the surface of the polymer shell. The differential scanning calorimeter (DSC) showed that the double-shell microcapsules had a high enthalpy of 114.58 J/g, which indicated almost no changes after experiencing 100 thermal cycles, indicating good thermal reliability. The microcapsules also showed good shape stability and antileakage performance, which displayed no shape change and leakage after heating at 60 °C for 30 min. In addition, the photothermal conversion efficiency of the double-shell microcapsules reached 91.3%. Thus, this study may promote the development of microencapsulated PCMs with multifunctionality, offering considerable application prospects in intelligent temperature management for smart textiles and wearable electronic devices in combination with their solar thermal energy conversion and storage performance.
The Effect of Low Positive Temperatures on the Formation of Secondary Metabolites in Rhodiola quadrifida (Pall.) Fisch. et C.A. Mey. In Vitro Cultures
Authors: Stepanova Anna Y. , Gladkov Evgeny A. , Tereshonok Dmitry V. , Selimov Renat N. , Goncharova Elisaveta N. , Solov’eva Aleksandra I.
Published: December 2022

Global warming is one of the most serious problems leading to changes in the distribution areas of species and biodiversity. Rhodiola quadrifida is a rare plant with adaptogenic properties and grows in the highlands in a narrow temperature range of 2–15 °C. The aim of our work was to study the growth and content of the main metabolites in two in vitro cultures of Rhodiola quadrifida at temperatures of 5, 15 and 25 °C. Hairy roots and calli were cultivated on agar medium for 28 days. The maximum values of the growth index were observed at 25 °C (2.32 and 2.12 for calli and hairy roots, respectively). HPLC-MS showed the absence of tyrosol and rosarin in both cultures, and rosin in the root culture. The content of salidroside changed slightly in calli and roots. Cultivation at 5 °C significantly stimulated the formation of rosin in calli. Only a residual amount of rosavin was noted in the roots, regardless of temperature. The content of rosin was higher in calli at 15 °C with a maximum content at the end of the cultivation cycle 25 µg/g DW. Thus, Rhodiola quadrifida will be able to grow with an increase in temperature by 10 °C but this will be accompanied by a significant reduction in its medicinal value
The Numerical Analysis of Non-Newtonian Blood Flow in a Mechanical Heart Valve
Authors: Chen Aolin , Basri Adi Azriff , Ismail Norzian Bin , Ahmad Kamarul Arifin
Published: December 2022

Background: The non-physiological structure of mechanical heart valves (MHVs) affects the blood flow field, especially the complex microstructure at the hinge. Numerous studies suggest that the blood flow field in the aortic area with an MHV can be considered Newtonian. However, the Newtonian assumption is occasionally unreasonable, where blood viscosity changes with shear rate, exhibiting non-Newtonian shear-thinning characteristics. Methods: In this research, a comprehensive study of the non-Newtonian effects on the hemodynamic behavior of MHVs was performed. The impact of the Newtonian hypothesis was investigated on the internal hemodynamics of MHVs. Several non-Newtonian and Newtonian models were used to analyze the chamber flow and blood viscosity. MHVs were modeled and placed in simplified arteries. After the unstructured mesh was generated, a simulation was performed in OpenFOAM to analyze its hemodynamic parameters. Results: In the study of the non-Newtonian viscosity model, the Casson model differs significantly from the Newtonian model, resulting in a 70.34% higher wall shear stress. In the modified Cross and Carreau models, the non-Newtonian behavior can significantly simulate blood in the MHV at different stages during initial and intermediate deceleration. The narrowing of the hinge region in particular, has a significant impact on evaluating blood rheology. The low flow rate and high wall shear force at the hinge can cause blood cell accumulation and injury time, resulting in hemolytic thrombosis. Conclusion: The results exhibit that the Newtonian hypothesis underestimates the hemodynamics of MHVs, whose complex structure leads to increased recirculation, stagnation, and eddy current structure, and a reasonable choice of blood viscosity model may improve the result accuracy. Modfied Cross and Carreau viscosity models effectively exhibit the shear-thinning behavior in MHV blood simulations.
Downtime Reduction with Fast Restart Function in a Beverage Production System
Authors: Jettanasen Chaiyan , Phannil Natthanon , Yoomak Suntiti , Thongsuk Surakit , Bunjongjit Sulee , Ngaopitakkul Atthapol
Published: December 2022

Bottled-beverage production systems require considerable machinery and sophisticated control systems. A malfunction in the production system can result in machine stoppages, thereby decreasing productivity and resulting in the production output not meeting the required target. Therefore, the problem of frequent stoppages of the production system must be resolved. The ‘Fast Restart Function’ is a proposed feature that can help reduce machine downtime by decreasing the time required for the product to drain from the conveyor. In this study, using this strategy, the investigated manufacturing system’s efficiency increased from 86.81% to 90.29%, enabling an increase in the average production capacity by 27,187 bottles per day, i.e., a 3.48 percent increment of the daily capacity. When employed in inefficient production systems or systems facing frequent shutdowns, this system is of considerable value for mitigating production stoppages.
Numerical Simulation and Optimization of SCR-DeNOx Systems for Coal-Fired Power Plants Based on a CFD Method
Authors: Wang Huifu , Sun Jian , Li Yong , Cao Zhen
Published: December 2022

In order to solve the problem of the uneven distribution of the flow and ammonia concentration field in the selective catalytic reduction (SCR) denitrification system of a 660 MW coal-fired power plant, a three-dimensional computational fluid dynamics (CFD) model was established at a scale of 1:1. The existing flow guide and ammonia fume mixing device were then calibrated and optimized. The relative standard deviation of the velocity field distribution upstream of the ammonia injection grid (AIG) was optimized from 15.4% to 9.9%, with a reasonable radius of the deflector at the inlet flue elbows, and the relative standard deviation of the velocity field distribution above the inlet surface of the first catalyst layer in the reactor was optimized from 25.4% to 10.2% by adjusting the angle between the deflector and the wall plate of the inlet hood. Additionally, with the use of a double-layer spoiler ammonia fume mixing device, the relative standard deviation of the ammonia mass concentration distribution above the inlet surface of the first catalyst layer in the reactor was optimized from 12.9% to 5.3%. This paper can provide a valuable reference with practical implications for subsequent research.
Solving Tea Blending Problems Using Interactive Fuzzy Multi-Objective Linear Programming
Authors: Jarernsuk Saran , Phruksaphanrat Busaba
Published: December 2022

Blending is a classical and well-known optimization problem that has been applied in the food, steel, and composite material industries. However, tea blending is more complicated than general problems due to the variety of products, processes, and sources of raw materials and semi-products. So, in this research, a fuzzy multi-objective model for the tea blending problem was proposed to minimize the total production cost and the deviation of quality target score; it provides a more robust and flexible method than existing models for complex real-world problems. Existing research works of a blending problem consider only raw material cost, but semi-product cost and processing cost are included in the proposed model that matches the actual case. Losses that occur during production are also incorporated. The selection of appropriate raw materials and semi-product sources can be obtained with the preferred levels of cost and quality by the proposed algorithm. The interactive fuzzy multi-objective programming to solve the problem has advantages over existing interactive programming methods. It is easy to manipulate interactively to obtain more efficient solutions than existing methods and both balanced and unbalanced solutions can be selected. The comparison of the results of an existing approach and the interactive fuzzy multi-objective programming algorithm for the tea industry is illustrated.
Oxygenated and Nitrated Polycyclic Aromatic Hydrocarbons: Sources, Quantification, Incidence, Toxicity, and Fate in Soil—A Review Study
Authors: Cao Wei , Yuan Jing , Geng Shuying , Zou Jing , Dou Junfeng , Fan Fuqiang
Published: December 2022

The genotoxicity, mutagenesis, and carcinogenic effects of polycyclic aromatic hydrocarbon (PAH) derivatives may exceed the parent PAHs. However, their influence on the soil environment has not been explored to a large extent. Oxygenated polycyclic aromatic hydrocarbons (OPAHs) and nitrated polycyclic aromatic hydrocarbons (NPAHs) are typical polar substituted compounds. We offer a review of the literature on the sources, quantification, incidence, toxicity, and transport of these compounds in soil. Although their environmental concentrations are lower than those of their parent compounds, they exert higher toxicity. Both types of substances are basically related to carcinogenesis. OPAHs are not enzymatically activated and can generate reactive oxygen species in biological cells, while NPAHs have been shown to be mutagenic, genotoxic, and cytotoxic. These compounds are largely derived from the transformation of PAHs, but they behave differently in soil because of their higher molecular weight and dissimilar adsorption mechanisms. Therefore, specialized knowledge of model derivatives is required. We also made recommendations for future directions based on existing research. It is expected that the review will trigger scientific discussions and provide a research basis for further study on PAH derivatives in the soil environment.
Effect of Annular Gas–Liquid Two-Phase Flow on Lateral Vibration of Drill String in Horizontal Drilling for Natural Gas Hydrate
Authors: Wang Baojin , Wang Liuci , Meng Xiangbo , Ren Fushen
Published: December 2022

NGH (natural gas hydrate) is a sort of green energy with huge reserves. When drilling and exploiting NGH, the complex drilling environment will aggravate the vibration of the drill string, which will destroy the stability of the NGH reservoir and make it decompose to produce a large amount of gas. Gas flows into the annular with the drilling fluid, filling the annular with a gas–liquid two-phase flow with a complex variation in the characteristic parameters of the pipe flow. The mixed gas–liquid annular flow will make the drill string vibration more complex and intense. In this study, the nonlinear mathematical model of the drill string lateral vibration is established by considering the influence of the internal and external fluids, gravity, and the bottom axial force on the lateral vibration of the drill string. The effect of the annular fluid velocity and gas content on the lateral vibration of the drill string was studied through experiments and numerical simulations. This study found that, with an increase in annular fluid velocity and gas content, the stability of the drill string is weakened, and the lateral vibration is intensified, so the effect of the annular fluid velocity on the lateral vibration of drill string is greater than that of the annular gas content.
Investigations of Lithium-Ion Battery Thermal Management System with Hybrid PCM/Liquid Cooling Plate
Authors: Zhang Ying , Fu Qinwen , Liu Yao , Lai Bozhen , Ke Zhaoqing , Wu Wei
Published: December 2022

To improve the operating performance of the large-capacity battery pack of electric vehicles during continuous charging and discharging and to avoid its thermal runaway, in this paper we propose a new hybrid thermal management system that couples the PCM with the liquid cooling plate with microchannels. The flow direction of the microchannel structure in the bottom plate is designed according to the characteristics of the large axial thermal conductivity of the battery, and the cooling performance of the whole system under continuous charge/discharge cycles is numerically simulated. The results show that the hybrid PCM/liquid cooling plate can maintain good cooling performance under the discharge process of a large-capacity battery pack. After each cycle the temperature of the battery pack can be reduced to less than 30°, and the maximum temperature change rate of multiple cycles is controlled within 0.8%. With the application of the hybrid PCM/liquid-cooled plate battery cooling system, a safe temperature range of the battery pack is ensured even under multiple cycles of charging and discharging. The present work can facilitate future optimizations of the thermal management system of the large-capacity battery pack of electric vehicles.
Optimization of Hydraulic Fine Blanking Press Control System Based on System Identification
Authors: Shu Yuwen , Liu Yanxiong , Xu Zhicheng , Zhao Xinhao , Chen Mingzhang
Published: December 2022

Fine-blanking is a molding process based on the common blanking process, which obtains hydrostatic stress through blank holder reverse jacking, in order to increase material plasticity. It requires special equipment, namely a fine-blanking press, to complete the fine-blanking process. In this paper, the problem of the speed of the slide block fluctuation found in the actual use of a 12,000 kN hydraulic fine-blanking press after multi-stage pressure source optimization is studied. Firstly, the mathematical model of the motion of the slide block in the blanking stage of the hydraulic fine blanking press is established, and the accurate mathematical model in the blanking stage of the hydraulic fine-blanking press is obtained through the least square method system identification experiment. Aiming at the complex working situation of the fine-blanking press, a phased PID control strategy is creatively proposed. The optimal PID control parameters are obtained by a genetic algorithm, and established a fuzzy PID controller for the blanking stage to accurately control the movement speed of the slide block. The results show that the new control strategy is very effective in improving the movement accuracy of the slide block, effectively improving the machining accuracy and reducing the impact vibration of the hydraulic system.
Magnesium Spinel Ferrites Development for FDM 3D-Printing Material for Microwave Absorption
Authors: Buzko Vladimir , Ivanin Sergey , Goryachko Alexander , Shutkin Ivan , Pushankina Polina , Petriev Iliya
Published: December 2022

The magnesium nanosized ferrite powder with formula MgFe2O4 was synthesized via a pyrochemical sol–gel glycine–nitrate method and annealed consistently at temperatures of up to 1300 °C. The MgFe2O4 ferrite samples’ microstructure was studied by SEM and XRD methods. According to the results of the studies, the increase in MgFe2O4 nanoparticles size from about 15 nm to micron-sized particles was observed when increasing annealing temperatures. The DC electrical conductivity of MgFe2O4 also clearly shows the change in conduction behavior of samples with increased calcination temperatures. The electromagnetic microwave properties of micron-sized particles of MgFe2O4 ferrite powder for a 1200 °C annealing temperature were studied for composites in paraffin matrix with produced magnetic filler mass concentration at 40% and 50%. The filament composites of polymer polylactic acid with MgFe2O4 ferrite powder samples were prepared by the FDM 3D-printing process and their microwave-absorbing properties were investigated. The application of developed PLA–MgFe2O4 ferrite filament for fabricating magnetic microwave-absorbing components also was demonstrated.
Two Strangers in the Eternal City: Border Thinking and Individualized Emerging Rituals as Anti-Patriarchal Epistemology
Authors: Fitriyah Lailatul
Published: December 2022

This paper is a work of autoethnography in which I (the author) observe critical practices that I and my colleague, Aisha, thought, said, and embodied during our tenure as the only Muslim Nostra Aetate Fellows at the St. Catherine Center for Interreligious Dialogue in the Vatican City, Italy. The paper focuses on our survival strategies that took on an interreligious and anti-patriarchal character within our interreligious, Muslim–Christian encounters. The framework of border thinking, as theorized by Maria Lugones and Gloria Anzaldúa, and the concept of emerging rituals proposed by Ronald Grimes, will serve as analytical tools to understand our practices. I argue that our embodied thoughts and practices, as seen from the lenses of emerging rituals and border thinking, represent an anti-patriarchal, interreligious epistemology that questions and deconstructs the hegemonic presence of patriarchal Catholic praxis around us within that specific context.
The Embodiment of Buddhist History: Interpretive Methods and Models of Sāsana Decline in Burmese Debates about Female Higher Ordination
Authors: Scott Tony
Published: December 2022

The mid-twentieth century was celebrated in Theravāda civilizations as the halfway point in the five-thousand-year history of the Buddha’s dispensation, the sāsana. Around this time in Burma, fierce debates arose concerning the re-establishment of the extinct order of Theravāda nuns. While women were understood as having a crucial role in supporting and maintaining the sāsana, without a sanctioned means of higher ordination, they were excluded from its centre, that is, as active agents in sāsana history. In this paper, I explore what was at stake in these debates by examining the arguments of two monks who publicly called for the reintroduction of the order of nuns, the Mingun Jetavana Sayadaw (1868–1955) and Ashin Ādiccavaṃsa (1881–1950). I will show that both used the enigmatic Milindapañha (Questions of Milinda) to present their arguments, but more than this, by drawing from their writings and biographies, it will be seen that their methods of interpreting the Pāli canon depended on their unique models of sāsana history, models which understood this halfway point as ushering in a new era of emancipatory promise. This promise was premised on the practice of vipassanā meditation by both lay men and especially women, the latter who, through their participation in the mass lay meditation movement, were making strong claims as dynamic players in the unfolding of sāsana history. The question of whether the order of nuns should be revived therefore hinged on the larger question of what was and was not possible in the current age of sāsana decline. Beyond this, what I aim to show is that mid-twentieth-century debates around female ordination concerned the very nature of the sāsana itself, as either a transcendent, timeless ideal, or as a bounded history embodied in the practice of both monks and nuns.
Guided by Hope and Not by Conscience: An Examination of the Arguments of Ivan Illich
Authors: Casey Cornelius
Published: December 2022

Ivan Illich was an incisive critic of aspects of contemporary Western cultures, such as the over-reach of obligatory institutionalized schooling, the excessive medicalization of society, and the dangers of global industrial development. From the outset there was a deeper edge to his work which concerned the formative, but ambivalent, influence of Christianity. His case is that a perversion of Christianity has come to be woven deep into the fabric of modernity and that ‘living by one’s conscience’ is one of the constitutive threads therein. Illich advocates living by hope and not by conscience. The article presents some lines along which Illich’s concern with the centrality of hope could be further developed.
Transnationalism and Hybridity in Religious Practices during the Migration Process: The Zera Beta Israel in Ethiopia and Israel
Authors: Talmi-Cohn Ravit
Published: December 2022

This article examines the complexity of religious practices and beliefs among a group of Zera Beta Israel (Falash Mura) members before, during, and a decade after their immigration process to Israel. This community, with roots in Judaism, converted to Christianity in the 19th century, complicating their request to immigrate to Israel along with Beta Israel members (Ethiopian Jews who had not converted to Christianity). Following an average 15-year wait in Ethiopian transit camps, they spent about two years in Israeli absorption centres and underwent conversion to rabbinic Judaism. This study aims to elucidate notions of religious, cultural, and oppositional transnationalism through life experiences described by Zera Beta Israel community members. Drawing on transnational theory and an interpretative qualitative approach, it develops and analyses 25 in-depth, semi-structured interviews and conversations conducted with members of the Zera Beta Israel community in Ethiopia and Israel. The findings challenge conventional binary perceptions and conceptual categories, such as Jewish–Christian or religious–secular and demonstrate the fluidity and complexity—the hybridity—that exists in the contexts of religion and immigration.
Chiara Lubich and the Intercultural Dialogue—Educational Relevance in a Time of New Conflicts
Authors: Kozubek Mariola Teresa , Silva Raul Augusto S. L.
Published: December 2022

As in a jigsaw puzzle, the pieces put together place before us the drama of the proliferation of new conflicts. Such are the times of today when people try to justify war on the grounds of belonging to different and incompatible cultures. Hence, there is an urgent need for a revival of intercultural dialogue and adequate education to foster it. Aware of the current challenge to peace, the two authors, who come from different geographical areas and cultures, seek through their research to highlight the educational value of Chiara Lubich’s charism, her work and that of the Focolare Movement she founded. To this end, they make use of the hermeneutic method of “text” analysis, understood as everything the person said, did and wrote. For this, they focus on what, with respect to the epistemology of education, consists in the real innovation, namely: the Lubich synoran, the Golden Rule as the axiological foundation of intercultural dialogue education, the Art of Loving as a method and the Cube of Peace as a teaching tool.
Dual-Branch Fusion of Convolutional Neural Network and Graph Convolutional Network for PolSAR Image Classification
Authors: Radman Ali , Mahdianpari Masoud , Brisco Brian , Salehi Bahram , Mohammadimanesh Fariba
Published: December 2022

Polarimetric synthetic aperture radar (PolSAR) images contain useful information, which can lead to extensive land cover interpretation and a variety of output products. In contrast to optical imagery, there are several challenges in extracting beneficial features from PolSAR data. Deep learning (DL) methods can provide solutions to address PolSAR feature extraction challenges. The convolutional neural networks (CNNs) and graph convolutional networks (GCNs) can drive PolSAR image characteristics by deploying kernel abilities in considering neighborhood (local) information and graphs in considering long-range similarities. A novel dual-branch fusion of CNN and mini-GCN is proposed in this study for PolSAR image classification. To fully utilize the PolSAR image capacity, different spatial-based and polarimetric-based features are incorporated into CNN and mini-GCN branches of the proposed model. The performance of the proposed method is verified by comparing the classification results to multiple state-of-the-art approaches on the airborne synthetic aperture radar (AIRSAR) dataset of Flevoland and San Francisco. The proposed approach showed 1.3% and 2.7% improvements in overall accuracy compared to conventional methods with these AIRSAR datasets. Meanwhile, it enhanced its one-branch version by 0.73% and 1.82%. Analyses over Flevoland data further indicated the effectiveness of the dual-branch model using varied training sampling ratios, leading to a promising overall accuracy of 99.9% with a 10% sampling ratio.
Maize Yield Prediction with Machine Learning, Spectral Variables and Irrigation Management
Authors: Baio Fábio Henrique Rojo , Santana Dthenifer Cordeiro , Teodoro Larissa Pereira Ribeiro , Oliveira Izabela Cristina de , Gava Ricardo , de Oliveira João Lucas Gouveia , Silva Junior Carlos Antonio da , Teodoro Paulo Eduardo , Shiratsuchi Luciano Shozo
Published: December 2022

Predicting maize yield using spectral information, temperature, and different irrigation management through machine learning algorithms provide information in a fast, accurate, and non-destructive way. The use of multispectral sensor data coupled with irrigation management in maize allows further exploration of water behavior and its relationship with changes in spectral bands presented by the crop. Thus, the objective of this study was to evaluate, by means of multivariate statistics and machine learning techniques, the relationship between irrigation management and spectral bands in predicting maize yields. Field experiments were carried out over two seasons (first and second seasons) in a randomized block design with four treatments (control and three additional irrigation levels) and eighteen sample repetitions. The response variables analyzed were vegetation indices (IVs) and crop yield (GY). Measurement of spectral wavelengths was performed with the Sensefly eBee RTK, with autonomous flight control. The eBee was equipped with the Parrot Sequoia multispectral sensor acquiring reflectance at the wavelengths of green (550 nm ± 40 nm), red (660 nm ± 40 nm), red-edge (735 nm ± 10 nm), and NIR (790 nm ± 40 nm). The blue length (496 nm) was obtained by additional RGB imaging. Data were subjected to Pearson correlations (r) between the evaluated variables represented by a correlation and scatter plot. Subsequently, the canonical analysis was performed to verify the interrelationship between the variables evaluated. Data were also subjected to machine learning (ML) analysis, in which three different input dataset configurations were tested: using only irrigation management (IR), using irrigation management and spectral bands (SB+IR), and using irrigation management, spectral bands, and temperature (IR+SB+Temp). ML models used were: Artificial Neural Network (ANN), M5P Decision Tree (J48), REPTree Decision Tree (REPT), Random Forest (RF), and Support Vector Machine (SVM). A multiple linear regression (LR) was tested as a control model. Our results revealed that Random Forest has higher accuracy in predicting grain yield in maize, especially when associated with the inputs SB+IR and SB+IR+Temp.
Novel Spatial–Spectral Channel Attention Neural Network for Land Cover Change Detection with Remote Sensed Images
Authors: Yang Xu , Lv Zhiyong , Atli Benediktsson Jón , Chen Fengrui
Published: December 2022

Land cover change detection (LCCD) with remote-sensed images plays an important role in observing Earth’s surface changes. In recent years, the use of a spatial-spectral channel attention mechanism in information processing has gained interest. In this study, aiming to improve the performance of LCCD with remote-sensed images, a novel spatial-spectral channel attention neural network (SSCAN) is proposed. In the proposed SSCAN, the spatial channel attention module and convolution block attention module are employed to process pre- and post-event images, respectively. In contrast to the scheme of traditional methods, the motivation of the proposed operation lies in amplifying the change magnitude among the changed areas and minimizing the change magnitude among the unchanged areas. Moreover, a simple but effective batch-size dynamic adjustment strategy is promoted to train the proposed SSCAN, thus guaranteeing convergence to the global optima of the objective function. Results from comparative experiments of seven cognate and state-of-the-art methods effectively demonstrate the superiority of the proposed network in accelerating the network convergence speed, reinforcing the learning efficiency, and improving the performance of LCCD. For example, the proposed SSCAN can achieve an improvement of approximately 0.17–23.84% in OA on Dataset-A.
A Multi-Robot Coverage Path Planning Method for Maritime Search and Rescue Using Multiple AUVs
Authors: Cai Chang , Chen Jianfeng , Yan Qingli , Liu Fen
Published: December 2022

In this study, we focus on the Multi-robot Coverage Path Planning (MCPP) problem for maritime Search And Rescue (SAR) missions using a multiple Autonomous Underwater Vehicle (AUV) system, with the ultimate purpose of efficiently and accurately discovering the target from sonar images taken by Side-Scan Sonar (SSS) mounted on the AUVs. Considering the specificities of real maritime SAR projects, we propose a novel MCPP method, in which the MCPP problem is transformed into two sub-problems: Area partitioning and single-AUV coverage path planning. The structure of the task area is first defined using Morse decomposition of the spike pattern. The area partitioning problem is then formulated as an AUV ordering problem, which is solved by developing a customized backtracking method to balance the workload and to avoid segmentation of the possible target area. As for the single-AUV coverage path planning problem, the SAR-A* method is adopted, which generates a path that preferentially visits the possible target areas and reduces the number of turns to guarantee the high quality of the resulting sonar images. Simulation results demonstrate that the proposed method can maintain the workload balance and significantly improve the efficiency and accuracy of discovering the target. Moreover, our experimental results indicate that the proposed method is practical and the mentioned specificities are useful for discovering targets.
Precipitable Water Vapor Retrieval Based on DPC Onboard GaoFen-5 (02) Satellite
Authors: Wang Chao , Shi Zheng , Xie Yanqing , Luo Donggen , Li Zhengqiang , Wang Decheng , Chen Xiangning
Published: December 2022

GaoFen-5 (02) (GF5-02) is a new Chinese operational satellite that was launched on 7 September 2021. The Directional Polarimetric Camera (DPC) is one of the main payloads and is mainly used for the remote sensing monitoring of atmospheric components such as aerosols and water vapor. At present, the DPC is in the stage of on-orbit testing, and no public DPC precipitable water vapor (PWV) data are available. In this study, a PWV retrieval algorithm based on the spectral characteristics of DPC data is developed. The algorithm consists of three parts: (1) the construction of the lookup table, (2) the calculation of water vapor absorption transmittance (WVAT) in the band at 910 nm, and (3) DPC PWV retrieval. The global PWV results derived from DPC data are spatially continuous, which can illustrate the global distribution of water vapor content well. The validation based on the Aerosol Robotic Network (AERONET) PWV data shows that the DPC PWV data have accuracy similar to that of Moderate-resolution Imaging Spectroradiometer (MODIS) PWV data, with coefficient correlation of determination (R2), mean absolute error (MAE), and relative error (RE) of 0.32, 0.30, and 0.93 using the DPC and 0.23, 0.36, and 0.96 using the MODIS, respectively. The results show that our proposed DPC PWV retrieval algorithm is feasible and has high accuracy. By analyzing the errors, we found that the calibration coefficients of the DPC in the 865 nm and 910 nm bands need to be updated.