bluuebunny/crossref_metadata_2025 huggingface dataset:
Laboratory Testing of Kinetic Sand as a Reference Material for Physical Modelling of Cone Penetration Test with the Possibility of Artificial Neural Network Application
Authors: Gago Filip , Vlcek Jozef , Valaskova Veronika , Florkova Zuzana
Published: May 2022

Cone Penetration Testing (CPT) is a quick survey in situ method through which soil parameters are not determined directly, but have to be estimated using derived relations between required soil parameter and soil resistance at the testing probe. Boundary conditions affect the reliability of the estimated soil parameters, therefore controlled laboratory conditions were applied to the intended CPT procedure analysis. Density, pycnometry, oedometer and direct shear tests of kinetic sand were performed to prove its usability as a reference testing material for further CPT laboratory analysis. The results of testing the kinetic sand are presented in this paper. Executed tests proved the kinetic sand as a reliable material in terms of the homogeneity and consistency of its physical and mechanical parameters. The material is utilizable as a substitution of cohesive sandy soils in physical modeling without the negative impact of the consistency-dependent behavior of fine-grained soils. However, some differences in parameters with respect to the natural soils should be taken into account. Neural network theory and numerical approach will be applied to the intended CPT laboratory analysis under controlled boundary conditions using kinetic sand to evaluate its potential for the determination of soil parameters.
Effect of Molten Pool Spatial Arrangement on Texture Evolution in Pulsed Laser Additive Manufacturing of Inconel 718
Authors: Cheng Manping , Luo Guoyun , Xiao Xianfeng , Song Lijun
Published: May 2022

The epitaxial growth of dendrites, which often results in a strong texture, is the most common phenomenon during the laser additive manufacturing process. In this study, the epitaxial growth of dendrites and texture evolution in three directions were studied by changing the z-increment, pulse period, and track offset, respectively. The influence of the molten pool interface on the growth and competition of dendrites is analyzed. Both green grains (<110> // BD) with rotated cube texture in the molten pool overlapping zones and red grains (<100> // BD) with fiber texture in the molten pool center zones coexist for different z-increment samples, forming the typical sandwich texture feature. In a short pulse period, the dendrites can grow directly epitaxially and form the strong fiber texture due to gentle interface and short distance. With the decrease of the track offset, the molten pool morphology changes from flat to narrow and deep. When θ is close to 90°, dendrites grow along the secondary dendrite arms at the overlapping zone, forming V-shape grains. This work also provides a promising method for texture customization for laser additive manufacturing.
Bacteria and Soil Enzymes Supporting the Valorization of Forested Soils
Authors: Borowik Agata , Wyszkowska Jadwiga , Kucharski Jan
Published: May 2022

To decompose forest biomass, microorganisms use specific enzymes from the class of oxidoreductases and hydrolases, which are produced by bacteria and soil fungi. In post-agricultural forest soils, bacteria adapt more easily to changing ecological conditions than fungi. The unique features of bacteria, i.e., tolerance and the ability to degrade a wide range of chemical compounds, prompted us to conduct research that contributes to the improvement of the broadly understood circular management of biomass production and economic efficiency. This study aimed to analyze changes in the microbiological activity and the activities of dehydrogenases, catalase, β-glucosidase, urease, arylsulfatase, acid phosphatase, and alkaline phosphatase in the soil sampled from under Picea abies (Pa), Pinus sylvestris (Ps), Larix decidua (Ld), Quercus robur (Qr), and Betula pendula (Bp), after 19 years. The control object was unforested soil. The studies allowed one to demonstrate the relationship between the activity of soil enzymes and the assemblages of culturable microorganisms and bacteria determined by the metagenomic method and tree species. Thus, it is possible to design the selection of tree species catalyzing enzymatic processes in soil. The strongest growth promoter of microorganisms turned out to be Quercus robur L., followed by Picea abies L., whereas the weakest promoters appeared to be Pinus sylvestris L. and Larix decidua M.
Adhesive Joints of Additively Manufactured Adherends: Ultrasonic Evaluation of Adhesion Strength
Authors: Kowalczyk Jakub , Ulbrich Dariusz , Sędłak Kamil , Nowak Michał
Published: May 2022

Adhesive joints are widely used in the construction of machines and motor vehicles. Manufacturers replace them with the welding and spot-welding methods due to the lack of damage to the material structure in the joint area. Moreover, it is aimed at reducing the weight of vehicles and producing elements with complex shapes. Therefore, additive manufacturing technology has been increasingly used in the production stage. This fact has not only changed the view on the possibilities of further development of the production technology itself, but it has also caused an intense interest among a greater number of companies in the advantages of structural optimization. There is a natural relationship between these two areas in the design and production, allowing for almost unlimited possibilities of designing new products. The main goal of the research described in this article was to determine the correlation between the strength of the adhesive joint of elements produced using additive technology and the parameters of the ultrasonic wave propagating in the area of the adhesive bond. The tests were carried out on samples made of AlSiMg0.6 material and a structural adhesive. Strength tests were performed to determine the shear force which damaged the joint. Furthermore, an ultrasonic echo technique enabling the determination of a nondestructive measure of the quality and strength of the joint was developed. The samples of the adhesive joints had a strength of about 18.75–28.95 MPa, which corresponded to an ultrasonic measure range of 4.6–7.8 dB. The determined regression relationship had a coefficient of determination at the level of 0.94. Additional ultrasonic tests of materials made with the additive technology confirmed its different acoustic properties in relation to aluminum produced with the standard casting or extrusion process. Designated dependence combining the mechanical strength and the decibel difference between the first and second impulses from the bottom of the joint may constitute the basis for the development of a nondestructive technique for testing the strength of adhesive joints.
Biomechanical Evaluation of Bone Atrophy and Implant Length in Four Implants Supporting Mandibular Full-Arch-Fixed Dentures
Authors: Huang Heng-Li , Tsai Hui-Ling , Wu Yu-Ling , Hsu Jui-Ting , Wu Aaron Yu-Jen
Published: May 2022

Residual alveolar ridge resorption often occurs after tooth extraction, which causes issues requiring further prothesis rehabilitation. A treatment concept referred to as all-on-four, involving fixed dentures supported with four implants, was recently developed. The current study aimed to determine the effect of changing bone atrophy and implant length in all-on-four treatments on stress and strain in the surrounding bone of the implant. A three-dimensional finite element method was used in this research. The stress analysis was conducted with von Mises stress values. Two types of synthetic jawbone models with mild and moderate atrophy were used. Furthermore, two different implant lengths with a similar implant design and diameter were selected, and they were classified into eight models. Then, the bone model was assessed via a computed tomography (CT) scan and was transformed into a virtual model in Geomagic and SolidWorks with implant rebuilding. After modifying bone atrophy, the von Mises stresses in the surrounding bone of the implant were as follows: mild type 2 < mild type 3 < moderate type 3 < moderate type 4. The bone quantity change rate increased more than when bone conditions were limited. Compared with changes in implant lengths, the stresses in the peri-implant surrounding bone were generally higher in the 9 mm implant length group than in the 11.5 mm group. However, the results did not significantly differ. In conclusion, the von Mises stress and strain increased in the models with moderate atrophy and low-density trabecular bone. Hence, bone atrophy and its presurgical diagnosis in long-term implant prognosis are crucial.
Assessment of the Influence of Additives on the Mechanical Properties and Machinability of Al-11%Si Cast Alloys: Application of DOE and ANOVA Methods
Authors: Zedan Yasser , Songmene Victor , Samuel Agnes M. , Samuel Fawzy H. , Doty Herbert W.
Published: May 2022

In the present study, the statistical design of experiments (DOE) method was applied to study and control the properties of near-eutectic Al-11%Si alloys. In this study, we developed regression equations between response variables, including hardness, yield stress, ultimate tensile stress, elongation, total cutting force, cutting power, and tool life, and varying factors which included the percentage of the alloying element in the composition and the modification level. These equations may be analyzed quantitatively to acquire an understating of the effects of the main variables and their interactions on the mechanical behavior and the machinability of the alloy under investigation. Analysis of variance (ANOVA) was performed to verify the fit and adequacy of the developed mathematical models. The results show that increasing the levels of Cu and Fe results in an increase in hardness, yield stress and ultimate tensile strength in both modified and non-modified alloys. On the other hand, both Cu and Fe appear to affect the elongation adversely, whereas the Sr level shows a positive effect on the elongation percentage. We found that the Sr level had the most significant effect on the cutting forces and cutting power, followed by Fe and Cu contents.
Aerobic Biostabilization of the Organic Fraction of Municipal Solid Waste—Monitoring Hot and Cold Spots in the Reactor as a Novel Tool for Process Optimization
Authors: Stegenta-Dąbrowska Sylwia , Randerson Peter F. , Białowiec Andrzej
Published: May 2022

The process of aerobic biostabilization (AB) has been adopted for treatment of the organic fraction of municipal solid waste (OFMSW). However, thermal gradients and some side effects in the bioreactors present difficulties in optimization of AB. Forced aeration is more effective than natural ventilation of waste piles, but “hot and cold spots” exist due to inhomogeneous distribution of air and heat. This study identified the occurrence of hot and cold spots during the OFMSW biostabilization process at full technical scale. It was shown that the number of hot and cold spots depended on the size of the pile and aeration rate. When the mass of stabilized waste was significantly lower and the aeration rate was two-fold higher the number of anaerobic hot spots decreased, while cold spots increased. In addition, the results indicated that pile construction with sidewalls decreased the number of hot spots. However, channelizing the airflow under similar conditions increased the number of cold spots. Knowledge of the spatial and temporal distribution of process gases can enable optimization and adoption of the OFMSW flow aeration regime. Temperature monitoring within the waste pile enables the operator to eliminate undesirable “hot spots” by modifying the aeration regime and hence improve the overall treatment efficiency.
Microstructure and Mechanical Properties of TiAl Matrix Composites Reinforced by Carbides
Authors: Yang Ying , Liang Yongfeng , Li Chan , Lin Junpin
Published: May 2022

TiAl alloys have the potential to become a new generation of high-temperature materials due to their lightweight and high-strength properties, while the brittleness at room temperature and microstructure stability at elevated temperature are the key problems. The preparation of composite materials is an effective way to solve these problems, because the mechanical properties of TiAl matrix composites can be improved by the close combination of the reinforced phase and matrix. The preparation methods, microstructure, and mechanical properties of TiAl matrix composites reinforced by carbides are reviewed from the literature in this paper. A comprehensive summary of the effect of C on TiAl alloys can reveal the relationship between the microstructure and mechanical properties and provide guidance for subsequent experimental works. Two forms of C in TiAl matrix composites are reviewed: solid solutions in matrix and carbide precipitations. For TiAl alloys, the minimum carbon content for the carbide precipitation is about 0.5 at.% for low-Nb-containing TiAl alloys and about 0.8 at.% for high-Nb-TiAl alloys. An appropriate amount of C can improve the tensile properties and flexural strength of TiAl alloys. The hardness of the composites is higher than that of pure TiAl due to solution strengthening when the carbon content is low. The minimum creep rate of TiAl alloys can be reduced by one order of magnitude by adding C at the amount near the solubility limit.
Editorial for Special Issue “Detrital Mineral U/Pb Age Dating and Geochemistry of magmatic Products in Basin Sequences: State of the Art and Progress”
Authors: Winkler Wilfried , von Quadt Albrecht
Published: May 2022

In general, provenance analysis has developed over the past 70 years into an enormously important tool in sediment investigations, both enabling solving earth science questions in basic research and practically applying it to mineral exploration [...]
Investigating the Morphology and Mechanics of Biogenic Hierarchical Materials at and below Micrometer Scale
Authors: Soleimani Mohammad , van den Broek Sten J. J. , Joosten Rick R. M. , van Hazendonk Laura S. , Maddala Sai P. , van Breemen Lambert C. A. , van Benthem Rolf A. T. M. , Friedrich Heiner
Published: May 2022

Investigating and understanding the intrinsic material properties of biogenic materials, which have evolved over millions of years into admirable structures with difficult to mimic hierarchical levels, holds the potential of replacing trial-and-error-based materials optimization in our efforts to make synthetic materials of similarly advanced complexity and properties. An excellent example is biogenic silica which is found in the exoskeleton of unicellular photosynthetic algae termed diatoms. Because of the complex micro- and nanostructures found in their exoskeleton, determining the intrinsic mechanical properties of biosilica in diatoms has only partly been accomplished. Here, a general method is presented in which a combination of in situ deformation tests inside an SEM with a realistic 3D model of the frustule of diatom Craspedostauros sp. (C. sp.) obtained by electron tomography, alongside finite element method (FEM) simulations, enables quantification of the Young’s modulus (E = 2.3 ± 0.1 GPa) of this biogenic hierarchical silica. The workflow presented can be readily extended to other diatom species, biominerals, or even synthetic hierarchical materials.
Analysis of Biomechanical and Biochemical Markers of Rat Muscle Soleus Fatigue Processes Development during Long-Term Use of C60 Fullerene and N-Acetylcysteine
Authors: Nozdrenko Dmytro , Prylutska Svitlana , Bogutska Kateryna , Cherepanov Vsevolod , Senenko Anton , Vygovska Oksana , Khrapatyi Sergii , Ritter Uwe , Prylutskyy Yuriy , Piosik Jacek
Published: May 2022

The development of an effective therapy aimed at restoring muscle dysfunctions in clinical and sports medicine, as well as optimizing working activity in general remains an urgent task today. Modern nanobiotechnologies are able to solve many clinical and social health problems, in particular, they offer new therapeutic approaches using biocompatible and bioavailable nanostructures with specific bioactivity. Therefore, the nanosized carbon molecule, C60 fullerene, as a powerful antioxidant, is very attractive. In this study, a comparative analysis of the dynamic of muscle soleus fatigue processes in rats was conducted using 50 Hz stimulation for 5 s with three consistent pools after intraperitoneal administration of the following antioxidants: C60 fullerene (a daily dose of 1 mg/kg one hour prior to the start of the experiment) and N-acetylcysteine (NAC; a daily dose of 150 mg/kg one hour prior to the start of the experiment) during five days. Changes in the integrated power of muscle contraction, levels of the maximum and minimum contraction force generation, time of reduction of the contraction force by 50% of its maximum value, achievement of the maximum force response, and delay of the beginning of a single contraction force response were analyzed as biomechanical markers of fatigue processes. Levels of creatinine, creatine phosphokinase, lactate, and lactate dehydrogenase, as well as pro- and antioxidant balance (thiobarbituric acid reactive substances, hydrogen peroxide, reduced glutathione, and catalase activity) in the blood of rats were analyzed as biochemical markers of fatigue processes. The obtained data indicate that applied therapeutic drugs have the most significant effects on the 2nd and especially the 3rd stimulation pools. Thus, the application of C60 fullerene has a (50–80)% stronger effect on the resumption of muscle biomechanics after the beginning of fatigue than NAC on the first day of the experiment. There is a clear trend toward a positive change in all studied biochemical parameters by about (12–15)% after therapeutic administration of NAC and by (20–25)% after using C60 fullerene throughout the experiment. These findings demonstrate the promise of using C60 fullerenes as potential therapeutic nanoagents that can reduce or adjust the pathological conditions of the muscular system that occur during fatigue processes in skeletal muscles.
Synthesis of Al–Al2O3–CNF Composite by Cold Spray Method: Powder Preparation and Synthesized Objects Characterization
Authors: Nalivaiko Anton Yu. , Doroshenko Vitaliy V. , Kuang Nguyen , Ozherelkov Dmitriy Yu. , Pelevin Ivan A. , Gromov Alexander A.
Published: May 2022

This paper is devoted to studying the composite material of the aluminum–alumina–carbon nanofiber (CNF) system. The paper considers in detail the process of preparation of the specified composite by ball milling, as well as the process of synthesis of a solid object (coating) by the cold spray method. The synthesized objects were studied using optical and electron microscopy, and the hardness of objects of various compositions was measured. The processes of interaction of composite particles are discussed in detail. The influence of CNF on the distribution of particles in a solid object and on the hardness of objects has been considered and discussed.
Usual Intake of Flavonoids Is Inversely Associated with Metabolic Syndrome in African American and White Males but Not Females in Baltimore City, Maryland, USA
Authors: Sebastian Rhonda S. , Fanelli Kuczmarski Marie T. , Goldman Joseph D. , Moshfegh Alanna J. , Zonderman Alan B. , Evans Michele K.
Published: May 2022

Despite research that suggests flavonoids protect against metabolic syndrome (MetS) and evidence that intake of these compounds differs by race, knowledge about whether flavonoid–MetS associations vary among racial groups is limited. This study sought to estimate usual total flavonoid intake in African American and White adults and assess its sex- and sex/race-specific associations with MetS and its risk factors. Analysis of cross-sectional data from 1837 adults participating in the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study were analyzed. Usual total flavonoid intake was estimated using the NCI Method, and logistic regression measured its linkages with health outcomes. Among males overall and when stratified by race, odds of MetS and its risk factors low high-density lipoprotein cholesterol (HDL-C) and elevated glucose were lower at the 75th percentile of usual total flavonoid intake than at the 25th percentile (OR for MetS = 0.62; 95% CI = 0.53, 0.71). However, low HDL-C and elevated glucose were positively associated with usual flavonoid intake among females. The comparable associations by race within sex imply that the relationships between flavonoid and health outcomes may be evident across an array of intakes.
Network Pharmacology Approach for Medicinal Plants: Review and Assessment
Authors: Noor Fatima , Tahir ul Qamar Muhammad , Ashfaq Usman Ali , Albutti Aqel , Alwashmi Ameen S. S. , Aljasir Mohammad Abdullah
Published: May 2022

Natural products have played a critical role in medicine due to their ability to bind and modulate cellular targets involved in disease. Medicinal plants hold a variety of bioactive scaffolds for the treatment of multiple disorders. The less adverse effects, affordability, and easy accessibility highlight their potential in traditional remedies. Identifying pharmacological targets from active ingredients of medicinal plants has become a hot topic for biomedical research to generate innovative therapies. By developing an unprecedented opportunity for the systematic investigation of traditional medicines, network pharmacology is evolving as a systematic paradigm and becoming a frontier research field of drug discovery and development. The advancement of network pharmacology has opened up new avenues for understanding the complex bioactive components found in various medicinal plants. This study is attributed to a comprehensive summary of network pharmacology based on current research, highlighting various active ingredients, related techniques/tools/databases, and drug discovery and development applications. Moreover, this study would serve as a protocol for discovering novel compounds to explore the full range of biological potential of traditionally used plants. We have attempted to cover this vast topic in the review form. We hope it will serve as a significant pioneer for researchers working with medicinal plants by employing network pharmacology approaches.
Infrared Small Target Detection by Modified Density Peaks Searching and Local Gray Difference
Authors: Wu Mo , Chang Lin , Yang Xiubin , Jiang Li , Zhou Meili , Gao Suining , Pan Qikun
Published: May 2022

Infrared small target detection is a challenging task with important applications in the field of remote sensing. The idea of density peaks searching for infrared small target detection has been proved to be effective. However, if high-brightness clutter is close to the target, the distance from the target pixel to the surrounding density peak will be very small, which easily leads to missing detection. In this paper, a new detection method, named modified density peaks searching and local gray difference (MDPS-LGD), is proposed. First, a local heterogeneity indicator is used as the density to suppress high-brightness clutter, and an iterative search is adopted to improve the efficiency in the process of searching for density peaks. Following this, a local feature descriptor named the local gray difference indicator (LGD) is proposed according to the local features of the target. In order to highlight the target, we extract the core area of the density peak by a random walker (RW) algorithm, and take the maximum response of the minimum gray difference element in the core region as the LGD of the density peak. Finally, targets are extracted using an adaptive threshold. Extensive experimental evaluation results in various real datasets demonstrate that our method outperforms state-of-the-art algorithms in both background suppression and target detection.
Synthesis and Characterization of Crosslinked Castor Oil-Based Polyurethane Nanocomposites Based on Novel Silane-Modified Isocyanate and Their Potential Application in Heat Insulating Coating
Authors: Meng Yuan , Chen Ken , Yang Yuyin , Jiang Tao , Hao Tonghui , Lu Xiaoju , Zhang Qunchao
Published: May 2022

An isocyanate with trimethoxysilane groups at the side chains (IPDI-M) was synthesized via an addition between the mercaptopropyl trimethoxysilane groups (MPTMS) and IPDI tripolymer (IPDI-T). Then, silane grafted isocyanate as the functional hard segment, castor oil as the soft segment, poly (ethylene adipate) diol (PEA) as the chain extender, and MPTMS as an end-capping reagent were applied to form a series of organosilicon hybrid bio-based polyurethane (CPUSi). The effect of the IPDI-M contents on the thermal stability, mechanical properties, and surface properties of the resulting product was systematically investigated. Profit from the Si–O–Si crosslinked structures formed from MPTMS curing, the tensile strength, and Young’s modulus of the resulting products increased from 9.5 MPa to 22.3 Mpa and 4.05 Mpa to 81.59 Mpa, respectively, whereas the elongation at break decreased from 342% to 101%. The glass transition temperature, thermal stability, transparency, hydrophobicity, and chemical resistance were remarkably strengthened for the obtained organosilicon-modified polyurethane with the increasing MPTMS content. At the end of the work, the thermal insulation coating that was based on CPUSi and ATO can effectively block near-infrared rays, and the temperature difference between the inside and outside of the film reached 15.1 °C.
Precipitation Microphysics of Tropical Cyclones over Northeast China in 2020
Authors: Zhang Aoqi , Chen Yilun , Pan Xiao , Hu Yuanyuan , Chen Shumin , Li Weibiao
Published: May 2022

Landfalling tropical cyclones (TCs) in Northeast China are rare because of the region’s high latitude (>40°N). In 2020, Northeast China was affected by three TCs within half a month—the first time on record. We used the Global Precipitation Measurement orbital dataset to study the precipitation microphysics during the TC period in Northeast China in 2020 (2020-TC), and during September in this region from 2014 to 2019 (hereafter September 2014–September 2019). FY-4A was used to provide cloud top height (CTH). The results show that, compared with September 2014–September 2019, the 2020-TC precipitation has stronger precipitation ice productivity, weaker deposition efficiency, stronger riming, and stronger coalescence processes. The storm top height (STH), CTH, and the difference between the two (CTH-STH) are indicative of the near-surface droplet size distribution (DSD), but there are differences: STH and CTH-STH both correlate significantly with mean mass-weighted drop diameter, whereas only the positive correlation between CTH and normalized drop concentration parameter passes the significance test. These results reveal for the first time the precipitation microphysics of landfalling TCs in Northeast China, and allow discussion of the validity of convective intensity indicators from the perspective of DSD.
Sparse Regularization with a Non-Convex Penalty for SAR Imaging and Autofocusing
Authors: Zhang Zi-Yao , Pappas Odysseas , Rizaev Igor G. , Achim Alin
Published: May 2022

In this paper, SAR image reconstruction with joint phase error estimation (autofocusing) is formulated as an inverse problem. An optimization model utilising a sparsity-enforcing Cauchy regularizer is proposed, and an alternating minimization framework is used to solve it, in which the desired image and the phase errors are estimated alternatively. For the image reconstruction sub-problem (f-sub-problem), two methods are presented that are capable of handling the problem’s complex nature. Firstly, we design a complex version of the forward-backward splitting algorithm to solve the f-sub-problem iteratively, leading to a complex forward-backward autofocusing method (CFBA). For the second variant, techniques of Wirtinger calculus are utilized to minimize the cost function involving complex variables in the f-sub-problem in a direct fashion, leading to Wirtinger alternating minimization autofocusing (WAMA) method. For both methods, the phase error estimation sub-problem is solved by simply expanding and observing its cost function. Moreover, the convergence of both algorithms is discussed in detail. Experiments are conducted on both simulated and real SAR images. In addition to the synthetic scene employed, the other SAR images focus on the sea surface, with two being real images with ship targets, and another two being simulations of the sea surface (one of them containing ship wakes). The proposed method is demonstrated to give impressive autofocusing results on these datasets compared to state-of-the-art methods.
Rossby Waves in Total Ozone over the Arctic in 2000–2021
Authors: Zhang Chenning , Grytsai Asen , Evtushevsky Oleksandr , Milinevsky Gennadi , Andrienko Yulia , Shulga Valery , Klekociuk Andrew , Rapoport Yuriy , Han Wei
Published: May 2022

The purpose of this work is to study Rossby wave parameters in total ozone over the Arctic in 2000–2021. We consider the averages in the January–March period, when stratospheric trace gases (including ozone) in sudden stratospheric warming events are strongly disturbed by planetary waves. To characterize the wave parameters, we analyzed ozone data at the latitudes of 50°N (the sub-vortex area), 60°N (the polar vortex edge) and 70°N (inner region of the polar vortex). Total ozone column (TOC) measurements over a 22-year time interval were used from the Total Ozone Mapping Spectrometer/Earth Probe and Ozone Mapping Instrument/Aura satellite observations. The TOC zonal distribution and variations in the Fourier spectral components with zonal wave numbers m = 1–5 are presented. The daily and interannual variations in TOC, amplitudes and phases of the spectral wave components, as well as linear trends in the amplitudes of the dominant quasi-stationary wave 1 (QSW1), are discussed. The positive TOC peaks inside the vortex in 2010 and 2018 alternate with negative ones in 2011 and 2020. The extremely low TOC at 70°N in 2020 corresponds to severe depletion of stratospheric ozone over the Arctic in strong vortex conditions due to anomalously low planetary wave activity and a high positive phase of the Arctic Oscillation. Interannual TOC variations in the sub-vortex region at 50°N are accompanied by a negative trend of −4.8 Dobson Units per decade in the QSW1 amplitude, statistically significant at 90% confidence level, while the trend is statistically insignificant in the vortex edge region and inside the vortex due to the increased variability in TOC and QSW1. The processes associated with quasi-circumpolar migration and quasi-stationary oscillation of the wave-1 phase depending on the polar vortex strength in 2020 and 2021 are discussed.
Azimuth-Sensitive Object Detection of High-Resolution SAR Images in Complex Scenes by Using a Spatial Orientation Attention Enhancement Network
Authors: Ge Ji , Wang Chao , Zhang Bo , Xu Changgui , Wen Xiaoyang
Published: May 2022

The scattering features of objects in synthetic aperture radar (SAR) imagery are highly sensitive to different azimuth angles, and detecting azimuth-sensitive objects in complex scenes becomes a challenging task. To address this issue, we propose a novel framework called the spatial orientation attention enhancement network (SOAEN) by using aircraft detection in complex scenes of SAR imagery as a case study. Taking YOLOX as the basic framework, this framework introduces the inverted pyramid ConvMixer network (IPCN), the spatial-orientation-enhanced path aggregation feature pyramid network (SOEPAFPN), and the anchor-free decoupled head (AFDH) to achieve performance improvement. A spatial orientation attention module is proposed and introduced into the path aggregation feature pyramid network to form a new structure, the SOEPAFPN, for capturing feature transformations in different directions, highlighting object features and suppressing background effects; the IPCN is adapted to replace the backbone network of YOLOX for enhancing the multiscale feature extraction capability and reducing the computational complexity, while the AFDH is used to decouple object localization and classification to improve the efficiency and accuracy of object localization and classification. The experimental results of the multiple real complex scenes on Gaofen-3 1 m images show that the proposed method achieves the highest detection accuracy, with an average detection rate of 91.22% compared with the YOLO series networks.
CIM-Based Smart Pose Detection Sensors
Authors: Chou Jyun-Jhe , Chang Ting-Wei , Liu Xin-You , Wu Tsung-Yen , Chen Yu-Kai , Hsu Ying-Tuan , Chen Chih-Wei , Liu Tsung-Te , Shih Chi-Sheng
Published: May 2022

The majority of digital sensors rely on von Neumann architecture microprocessors to process sampled data. When the sampled data require complex computation for 24×7, the processing element will a consume significant amount of energy and computation resources. Several new sensing algorithms use deep neural network algorithms and consume even more computation resources. High resource consumption prevents such systems for 24×7 deployment although they can deliver impressive results. This work adopts a Computing-In-Memory (CIM) device, which integrates a storage and analog processing unit to eliminate data movement, to process sampled data. This work designs and evaluates the CIM-based sensing framework for human pose recognition. The framework consists of uncertainty-aware training, activation function design, and CIM error model collection. The evaluation results show that the framework can improve the detection accuracy of three poses classification on CIM devices using binary weights from 33.3% to 91.5% while that on ideal CIM is 92.1%. Although on digital systems the accuracy is 98.7% with binary weight and 99.5% with floating weight, the energy consumption of executing 1 convolution layer on a CIM device is only 30,000 to 50,000 times less than the digital sensing system. Such a design can significantly reduce power consumption and enables battery-powered always-on sensors.
Content Swapping: A New Image Synthesis for Construction Sign Detection in Autonomous Vehicles
Authors: Seong Hongje , Baik Seunghyun , Lee Youngjo , Lee Suhyeon , Kim Euntai
Published: May 2022

Construction signs alert drivers to the dangers of abnormally blocked roads. In the case of autonomous vehicles, construction signs should be detected automatically to prevent accidents. One might think that we can accomplish the goal easily using the popular deep-learning-based detectors, but it is not the case. To train the deep learning detectors to detect construction signs, we need a large amount of training images which contain construction signs. However, collecting training images including construction signs is very difficult in the real world because construction events do not occur frequently. To make matters worse, the construction signs might have dozens of different construction signs (i.e., contents). To address this problem, we propose a new method named content swapping. Our content swapping divides a construction sign into two parts: the board and the frame. Content swapping generates numerous synthetic construction signs by combining the board images (i.e., contents) taken from the in-domain images and the frames (i.e., geometric shapes) taken from the out-domain images. The generated synthetic construction signs are then added to the background road images via the cut-and-paste mechanism, increasing the number of training images. Furthermore, three fine-tuning methods regarding the region, size, and color of the construction signs are developed to make the generated training images look more realistic. To validate our approach, we applied our method to real-world images captured in South Korea. Finally, we achieve an average precision (AP50) score of 84.98%, which surpasses that of the off-the-shelf method by 9.15%. Full experimental results are available online as a supplemental video. The images used in the experiments are also released as a new dataset CSS138 for the benefit of the autonomous driving community.
A Soft Multi-Axis High Force Range Magnetic Tactile Sensor for Force Feedback in Robotic Surgical Systems
Authors: Rehan Muhammad , Saleem Muhammad Mubasher , Tiwana Mohsin Islam , Shakoor Rana Iqtidar , Cheung Rebecca
Published: May 2022

This paper presents a multi-axis low-cost soft magnetic tactile sensor with a high force range for force feedback in robotic surgical systems. The proposed sensor is designed to fully decouple the output response for normal, shear and angular forces. The proposed sensor is fabricated using rapid prototyping techniques and utilizes Neodymium magnets embedded in an elastomer over Hall sensors such that their displacement produces a voltage change that can be used to calculate the applied force. The initial spacing between the magnets and the Hall sensors is optimized to achieve a large displacement range using finite element method (FEM) simulations. The experimental characterization of the proposed sensor is performed for applied force in normal, shear and 45° angular direction. The force sensitivity of the proposed sensor in normal, shear and angular directions is 16 mV/N, 30 mV/N and 81 mV/N, respectively, with minimum mechanical crosstalk. The force range for the normal, shear and angular direction is obtained as 0–20 N, 0–3.5 N and 0–1.5 N, respectively. The proposed sensor shows a perfectly linear behavior and a low hysteresis error of 8.3%, making it suitable for tactile sensing and biomedical applications. The effect of the material properties of the elastomer on force ranges and sensitivity values of the proposed sensor is also discussed.
Inversion of Nitrogen Concentration in Apple Canopy Based on UAV Hyperspectral Images
Authors: Li Wei , Zhu Xicun , Yu Xinyang , Li Meixuan , Tang Xiaoying , Zhang Jie , Xue Yuliang , Zhang Canting , Jiang Yuanmao
Published: May 2022

As the major nutrient affecting crop growth, accurate assessing of nitrogen (N) is crucial to precise agricultural management. Although improvements based on ground and satellite data nitrogen in monitoring crops have been made, the application of these technologies is limited by expensive costs, covering small spatial scales and low spatiotemporal resolution. This study strived to explore an effective approach for inversing and mapping the distributions of the canopy nitrogen concentration (CNC) based on Unmanned Aerial Vehicle (UAV) hyperspectral image data in a typical apple orchard area of China. A Cubert UHD185 imaging spectrometer mounted on a UAV was used to obtain the hyperspectral images of the apple canopy. The range of the apple canopy was determined by the threshold method to eliminate the effect of the background spectrum from bare soil and shadow. We analyzed and screened out the spectral parameters sensitive to CNC, including vegetation indices (VIs), random two-band spectral indices, and red-edge parameters. The partial least squares regression (PLSR) and backpropagation neural network (BPNN) were constructed to inverse CNC based on a single spectral parameter or a combination of multiple spectral parameters. The results show that when the thresholds of normalized difference vegetation index (NDVI) and normalized difference canopy shadow index (NDCSI) were set to 0.65 and 0.45, respectively, the canopy’s CNC range could be effectively identified and extracted, which was more refined than random forest classifier (RFC); the correlation between random two-band spectral indices and nitrogen concentration was stronger than that of other spectral parameters; and the BPNN model based on the combination of random two-band spectral indices and red-edge parameters was the optimal model for accurately retrieving CNC. Its modeling determination coefficient (R2) and root mean square error (RMSE) were 0.77 and 0.16, respectively; and the validation R2 and residual predictive deviation (RPD) were 0.75 and 1.92. The findings of this study can provide a theoretical basis and technical support for the large-scale, rapid, and non-destructive monitoring of apple nutritional status.
Design Process and Implementation of Teacher Training Modules in Movement Integration: What Have We Learnt?
Authors: Kalma Maarja , Mägi Katrin , Mäestu Evelin , Mooses Kerli , Kull Merike
Published: May 2022

Substantial evidence shows that the current level of children’s physical activity (PA) is insufficient. Schools along with academic lessons can offer an effective avenue to increase children’s physical activity and decrease sedentary time. Teacher training in movement integration (MI) has been emphasized as an important strategy in facilitating less sedentary and more physically active lessons. The aim of this study was to explore the design process for developing a teacher training module for MI and its implementation within the comprehensive, school-based, physical activity program. Flexible co-creation methods with teachers were applied. Process evaluation was conducted through individual feedback surveys, observations in schools, evaluating the teacher’s MI mapping timetable, group feedback, and a follow-up study. The two-day module, a practical and flexible approach, ready-to-use resources, allocated time and autonomy for practice, communication with other teachers, and a whole school approach aligned with teachers’ needs are identified as key elements. A follow-up study after the training showed significant changes in teachers’ practices regarding the use of MI in the classroom. The study offers important insights into the design process and its successes and failures. The lessons learnt, a final model of designed seminars, and a toolbox of materials are presented.
Price Controls and Platform Ecosystem: A Comparative Analysis of Parking Applications between Beijing and London
Authors: Wang Zhong , Xu Rui
Published: May 2022

As a platform to improve the efficiency of matching supply and demand, parking applications once blossomed in many cities. However, some have achieved success while others quickly withered. By comparing the development of parking applications between Beijing and London, it is found that price controls are a key factor. Price controls include price limits and hourly limits. Flexible price or controlled duration facilitate platform sustainability, as these increase the supply side’s digital investment and willingness to access the platform, and also increase demanders’ willingness to use the platform. Meanwhile, flat and low pricing or no time limit will make the platform less attractive, since these reduce the supply and its mobility, and also discourage demanders from using the platform. This paper enriches the literature on the digital platform ecosystem and information systems (IS) and provides practical inspiration for urban parking management.
Investigating the Impacts of Behavioural-Change Interventions and COVID-19 on the Food-Waste-Generation Behaviours of Catered Students in the UK and India
Authors: Davison Nicholas , Young William , Ross Andrew , Cockerill Timothy , Rajput Shailendrasingh
Published: May 2022

A food-waste initiative was conducted at two university canteens in the UK and India to examine food-waste attitudes and opportunities for food-waste reduction. Interventions were carried out to reduce food waste in both canteens. In the Indian canteen, postintervention data also included COVID-19-related changes, such as a change from self-service to table service, as well as reduced menu choices and an improved estimation of the number of students requiring meals. Surveys and focus groups were conducted with students to better understand their food-waste-related attitudes, while interviews were carried out with university staff to better understand food-waste management. The study in the UK university canteen found that introducing table cards, posters, and signs led to food-waste reductions of 13%. Meanwhile, the study in the Indian university canteen found that the interventions and COVID-19 impacts led to food-waste reductions of 50%. Concerning food-waste-related differences between the UK and India, culture and food preferences were key reasons for food waste in India, with 40.5% more participants in India stating that they wasted food because the ‘food didn’t taste good’. Students in India were more concerned about social issues and food poverty related to food waste, with around 9% more participants stating that the ‘food could be used by others’. Meanwhile, students in the UK were more bothered by the economic and environmental impacts of food waste, with around 31% more participants stating food waste is ‘a waste of money’, and is ‘bad for the environment’ when compared to India. Key opportunities for both countries included adopting food-sharing initiatives, informed menu choices, and meal planning, as well as student-led engagement projects.
Linkage of Sustainability to Environmental Impact Assessment Using the Concept of Ecosystem Services: Lessons from Thailand
Authors: Swangjang Kanokporn
Published: May 2022

The concept of ecosystem services (ES) could help Environmental Impact Assessments (EIAs) contribute toward sustainability goals. This study aimed to systematically analyze the ES contents contained in Environmental Impact Statements (EISs) to ascertain whether they included appropriate data as a tool for project implementation in line with sustainability practices. The EISs were analyzed using the review criteria used to assess the criteria of good EIA practice, and these criteria were then integrated and linked to the concept of ES. The results indicated that the treatment of environmental impact studies from the perspective of impact assessment practice was advantageous; however, opposing results of the integration of ES in environmental impact studies were also found. The quality of EISs that reflect ES primarily depended on the project type. The highest quality of content to support ES was for baseline information. The contents in response to biodiversity and the relationship among sustainable indicators in the baseline stage, including the assessment of biodiversity, especially its loss and gain, and the identification of measures focusing on mitigation hierarchy, were inadequate. Consequently, these constraints affect the use of impact assessments as a tool to promote project activities in sustainable ways. An approach to integrate ES in EIAs was developed based on the findings of this study.