bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Functionalization of the Polycaprolactone Film Surface on the Mechanical and Biological Properties of the Film Itself
Authors: Nashchekina Yuliya , Chabina Alina , Moskalyuk Olga , Voronkina Irina , Evstigneeva Polina , Vaganov Gleb , Nashchekin Alexey , Yudin Vladimir , Mikhailova Nataliya
Published: November 2022

The lack of suitable functional groups for cell adhesion on the surface of Polycaprolactone (PCL) is one of the main limitations in order to use PCL for biomedical applications. The aim of this research is to modify the PCL film surface using arginine, via an aminolysis reaction. In this regard, after PCL films formation by casting method, they were immersed in arginine solutions of various concentration at room temperature or then heated to 40 °C and in the presence of isopropanol or without it. To assess the structure of the modified surface, its wettability, and mechanical properties, methods of measuring the contact angle and the strip tensile test were used, and to compare the degree of attachment and the rate of cell proliferation, the method of fluorescent staining of cultured cells was used. The change in protein synthesis by cells on the modified surface was assessed using Western blotting. The results obtained show that the treatment of PCL films with an aqueous solution of arginine at room temperature for 1 day increases the hydrophilicity of the surface. Wherein surface modification led to a two-fold decrease of mechanical strength and flow stress, but elongation increase by about 30% for PCL films after modification in 0.5 M aqueous arginine solution at room temperature. Moreover, cell attachment and proliferation, as well as collagen synthesis, were significantly enhanced after arginine modification. The proposed simple and effective method for modifying PCL films with arginine significantly expands the possibilities for developing biocompatible scaffolds for tissue engineering.
A Full Range Experimental Study of Amplitude- and Frequency-Dependent Characteristics of Rubber Springs
Authors: Shi Yanping , Li Juanjuan , Wang Yuan , Li Xuebing , Gao Yuanjing , Zhao Dong , Shi Baohui , Zou Lihua , Song Xiuduo , Shang Yuanyuan
Published: November 2022

This paper provides a comprehensive understanding of the amplitude- and frequency-dependent characteristics of rubber springs. The dynamic nonlinear inelasticity of rubber is a key academic problem for continuum mechanics and a bottleneck problem for the practical use of rubber structures. Despite intensive efforts witnessed in industrial applications, it still demands an unambiguous constitutive model for dynamic nonlinear inelasticity, which is known as the Payne effect. To this end, three types of rubber springs (shear-type (ST), compression-type (CT) and shear-compression-combination-type (SCCT)) were tested with amplitude and frequency sweeps in different conditions. We investigated and present changes in dynamic stiffness and loss factor with amplitude, frequency and the hysteresis loops of different rubber springs. We also propose a hypothesis and research strategy to study a constitutive model involving multiple factors of hyperelasticity, the Mullins effect, viscoelasticity and the Payne effect, which we hope will provide new ideas for the establishment of a constitutive equation.
Features of Composite Layers Created Using an Aqueous Suspension of a Fluoropolymer
Authors: Mashtalyar Dmitriy Valerievich , Nadaraia Konstantine Vakhtangovich , Belov Evgeny Alekseevich , Imshinetskiy Igor Mikhaylovich , Sinebrukhov Sergey Leonidovich , Gnedenkov Sergey Vasilevich
Published: November 2022

This paper presents a method for the formation of composite-polymer-containing coatings on MA8 Mg alloy by plasma electrolytic oxidation (PEO), followed by the deposition of a fluoropolymer from an aqueous suspension of superdispersed polytetrafluoroethylene. The Scanning Electron Microscope(SEM), Energy Dispersive Spectroscopy(EDS), and X-ray Diffraction(XRD) analyses established morphological features as well as elemental and phase composition of composite coatings. The fact that the pores are filled with a fluoropolymer has been experimentally confirmed. An assessment of the corrosion properties of formed composite coatings revealed a decrease in the corrosion current density by more than four orders of magnitude in comparison with the base PEO layer. The highest resistance to the damaging effects of a corrosive environment, according to the results of long-term exposure tests, was demonstrated by coatings after three treatments with polytetrafluoroethylene. The obtained polymer-containing coatings have antifriction properties, reducing the wear of the coatings by more than 27-fold in comparison with the base PEO layer. It was revealed that composite coatings have superhydrophobic properties: the value of the contact angle reaches 154°, and the hysteresis of the contact angle is less than 10°.
Ameliorating the Mechanical Parameters, Thermal Stability, and Wettability of Acrylic Polymer by Cement Filling for High-Efficiency Waterproofing
Authors: Abd-Elnaiem Alaa M. , Hussein Seenaa I. , Ali Nadia A. , Hakamy Ahmad , Mebed Abdelazim M.
Published: November 2022

Acrylic polymer/cement nanocomposites in dark and light colors have been developed for coating floors and swimming pools. This work aims to emphasize the effect of cement filling on the mechanical parameters, thermal stability, and wettability of acrylic polymer. The preparation was carried out using the casting method from acrylic polymer coating solution, which was added to cement nanoparticles (65 nm) with weight concentrations of (0, 1, 2, 4, and 8 wt%) to achieve high-quality specifications and good adhesion. Maximum impact strength and Hardness shore A were observed at cement ratios of 2 wt% and 4 wt%, respectively. Changing the filling ratio has a significant effect on the strain of the nanocomposites. The contact angle was increased as the concentration of additives and cement increased, indicating that the synthesized coating is not hydrophilic and does not allow water permeability through it. The results show that the acrylic polymer/cement with a cement ratio of 8 wt% is the best nanocomposite for high-efficiency waterproofing.
High-Throughput Sequencing as a Tool for the Quality Control of Microbial Bioformulations for Agriculture
Authors: Syromyatnikov Mikhail Y. , Nesterova Ekaterina Y. , Gladkikh Maria I. , Tolkacheva Anna A. , Bondareva Olga V. , Syrov Vladimir M. , Pryakhina Nina A. , Popov Vasily N.
Published: November 2022

Microbial bioformulations, due to their positive impact on the growth and development of plants, as well as the absence of harmful effects on the environment and humans, have a vast potential for mass introduction into agriculture. Assessing the quality of bioformulations, especially complex ones, is a difficult task. In this study, we show that high-throughput sequencing can be an effective tool for the quality control and safety of microbial bioformulations. By the method of high-throughput sequencing on the MiSeq platform, we studied 20 samples of commercially available microbial bioformulations. In parallel with this, bioformulations were studied by classical microbiological methods. The analysis showed the presence of extraneous undeclared bacterial genera by the manufacturer. Only 10% of the bioformulations fully corresponded to the commercial composition, and another 10% of the bioformulations did not contain the bacteria declared by the manufacturer in their composition at all. The bacterial composition of 80% of the bioformulations partially corresponded to the composition indicated on the package. The most frequent microbial bioformulations contaminants were Enterococcus, Lactobacillaceae, Klebsiella, Escherichia-Shigella and Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium. Universal methods for the quality control of bioformulations are needed. The advantages of high-throughput sequencing for the evaluation of bioformulations are considered in this work.
A Review of Process Systems Engineering (PSE) Tools for the Design of Ionic Liquids and Integrated Biorefineries
Authors: Chemmangattuvalappil Nishanth G. , Ng Denny K. S.
Published: November 2022

Over the years, the global process industry is continually improving in product development and process performances [...]
Multi-Response Modelling and Optimisation of Mechanical Properties of Al-Si Alloy Using Mixture Design of Experiment Approach
Authors: Poornesh M. , Bhat Shreeranga , Gijo E. V. , Bellairu Pavana Kumara , McDermott Olivia
Published: November 2022

The research aims to produce, model, and optimise the mechanical properties of novel composite material through a structured multidisciplinary approach. The primary objective is to combine materials science, mechanical engineering, and statistical concepts to ensure Design for Manufacturability (DFM) from the industrial perspective. More specifically, the article is intended to determine the optimal mixture components and predictive model of Al-Si alloy with Al2O3 by accommodating multi-responses that enable DFM. The study adopted ASTM standards to prepare and test the novel composite material. Additionally, the Mixture Design of Experiment (DOE) approach was used to design the experimentation and subsequent analysis. In addition, microstructural images, Cox Response Trace plot, and Response Optimiser plot are effectively utilised to draw robust inferences. For multi-response modelling and optimisation, the composite material’s mechanical properties, like impact strength, hardness, density, and tensile strength, are considered. The study determines that innovative composite material will yield better results when Al-Alloy is 94.65 wt% and Al2O3 is 5.35 wt% from a multi-responses perspective. Further, it provides predictive models with a high level of predictability. Besides, the research shows that novel composite material has better mechanical properties from a practical perspective. The article not only provides the mechanical properties of a new class of material but also shows the effective utilisation of material science and statistical concepts to develop the novel material in a structured manner. This composite material can be used as a replacement for various parts of automobiles and aircraft. Additionally, researchers can use the article’s modelling and optimisation approach as a paradigm to create durable composite materials.
Performance Improvement of Micro-Abrasive Jet Blasting Process for Al 6061
Authors: Kwon Dae-Kyu , Lee Jae-Hak
Published: November 2022

Aluminum 6061 is a precipitation-hardened alloy, containing magnesium and silicon as its major alloying element, and it is widely used in industries due to its remarkable mechanical properties and weld ability. Several types of machining manners are researched for aluminum 6061 alloys, and micro-abrasive jet blasting (μ-AJM) is one of the most developed processes for improving surface roughness. When operating μ-AJM on aluminum alloys, sufficient consideration of environmental variables such as particle types, nozzle diameter, pressure, standoff distance, and injection time is a prerequisite for the appropriate degree of roughness. To find the optimal conditions, a statistical method of analysis of variables was used to investigate the maximum value for depth, diameter, width, etc., of the blasting surface. According to experimental results, multiple factors have a great influence on the condition of surface roughness. The blasting processes were conducted as square and cylindrical experiments, and the parameters for optimal conditions have been derived from a surface roughness measurement system.
Chemical, Microbiological, and Sensory Analysis Benefits Leading to Shelf-Life Extension of Minced Beef Meat Using Essential Oil of Oregano Contained in Xanthan Gum and Guar Gum Edible Coating
Authors: Alexandraki Maria , Valiakos George , Manouras Athanasios , Malissiova Eleni
Published: November 2022

In the present study, the effect of oregano essential oil, which is contained in xanthan gum and guar gum edible coating, was investigated in regard to its ability to assist with the preservation and the extension of the shelf life of minced beef meat when stored at 4 °C. Minced beef meat samples were coated with a mixture of xanthan gum and guar gum containing oregano essential oil at various levels (1–3%). The coated samples were compared with the control sample (uncoated) for bacteriological (i.e., total viable count, coliforms, and Enterobacteriaceae), physicochemical (pH), and sensorial properties (color and odor) on specific storage days (0, 3, 6, 9, and 12). There was greater microbial growth noted in the uncoated minced beef meat in comparison to the coated ones. Odor, color, and overall acceptability were significantly improved in the coated samples (p < 0.05). The chemical, bacteriological, and sensory analyses that were performed, evidenced the benefits that edible coating with oregano essential oil may have on the shelf life and quality of minced beef meat.
Biodegradation of Alachlor by a Newly Isolated Bacterium: Degradation Pathway and Product Analysis
Authors: Lee Hyosun , Kim Dong-Uk
Published: November 2022

Alachlor [2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl]acetamide] is a chloroacetanilide herbicide and has been widely used as a selective pre-emergent and post-emergent herbicide to control weeds and grass. Due to its wide usage, direct application on the ground, high solubility in water, and moderate persistence, alachlor and its metabolites have been detected in various environments. Therefore, there is an increasing concern about the environmental fate of alachlor and its metabolites. Microbial biodegradation is a main method of removal of alachlor in the natural environment. In this study, we isolated new alachlor degrading bacterium and proposed a novel alachlor-degrading pathway. The alachlor-degrading bacterial strain, GC-A6, was identified as Acinetobacter sp. using 16S rRNA gene sequence analysis. Acinetobacter sp. GC-A6 utilized alachlor as its sole carbon source and degraded 100 mg L−1 of alachlor within 48 h, which was the highest alachlor degradation efficiency. The degradation pathway of alachlor was studied using GC-MS analysis. Alachlor was initially degraded to 2-chloro-N-(2,6-diethylphenyl) acetamide, which was further degraded to 2,6-diethylaniline and 7-ethylindoline, respectively. 2,6-Diethylaniline was transformed into N-(2,6-diethylphenyl) formamide. N-(2,6-diethylphenyl) formamide was a first-reported intermediate during the degrading pathway of alachlor by single isolate.
Experimental Studies of the Effective Thermal Conductivity of Polyurethane Foams with Different Morphologies
Authors: Soloveva Olga V. , Solovev Sergei A. , Vankov Yuri V. , Shakurova Rozalina Z.
Published: November 2022

Polyurethane foam (PUF) is actively used for thermal insulation. The main characteristic of thermal insulation is effective thermal conductivity. We studied the effective thermal conductivity of six samples of PUF with different types and sizes of cells. In the course of the research, heat was supplied to the foam using an induction heater in three different positions: above, below, or from the side of the foam. The studies were carried out in the temperature range from 30 to 100 °C. The research results showed that for all positions of the heater, the parameter that makes the greatest contribution to the change in thermal conductivity is the cell size. Two open-cell foam samples of different sizes (d = 3.1 mm and d = 0.725 mm) have thermal conductivity values of 0.0452 and 0.0287 W/m⸱K, respectively, at 50 °C. In the case of similar cell sizes for any position of the heater, the determining factor is the type of cells. Mixed-cell foam (d = 3.28 mm) at 50 °C has a thermal conductivity value of 0.0377 W/m⸱K, and open-cell foam (d = 3.1 mm) at the same temperature has a thermal conductivity value of 0.0452 W/m⸱K. The same foam sample shows different values of effective thermal conductivity when changing the position of the heater. When the heater is located from below the foam, for example, mixed-cell foam (d = 3.4 mm) has higher values of thermal conductivity (0.0446 W/m⸱K), than if the heater is located from above (0.0390 W/m⸱K). There are different values of the effective thermal conductivity in the upper and lower parts of the samples when the heater is located from the side of the foam. At 80 °C the difference is 40% for the open-cell foam (d = 3.1 mm).
Kinetics of Ion-Exchange Extraction of Lithium from Aqueous Solutions by Protonated Potassium Polytitanates
Authors: Vikulova Maria , Maximova Lilia , Rudyh Valeria , Gorshkov Nikolay , Gorokhovsky Alexander
Published: November 2022

In this work, protonated forms of potassium polytitanate were obtained by treating the precursor in HCl solution at pH 2.0, 3.0, 4.0, 5.0, 6.0, or 7.0. The synthesized materials were studied using XRD, FTIR, and XRF. The ion-exchange properties were studied using a LiCl solution with a concentration of C(Li+) = 0.01 mol/L. It was shown that extraction of lithium by potassium polytitanates is dependent on their protonation degree. It has been established that the samples with the highest degree of protonation obtained at pH = 2.0 and 3.0 have the highest efficiency in the ion-exchange extraction of Li+ ions from an aqueous solution. For determination of exchange ion rates and the mechanism of the ion-exchange process, pseudo-first- and pseudo-second-order models as well as the Weber–Morris intraparticle diffusion model, were employed. Experimental data with their participation are in good agreement with the pseudo-second-order kinetic model. The calculated kinetic parameters were qe = 0.47–0.52 mmol/g and k2 = 0.25–0.43, depending on the protonation degree of potassium polytitanate. The obtained experimental and calculated values of the sorption capacity were compared with the cation-exchange capacity of materials studied. According to the kinetics study, the mechanism of lithium adsorption by potassium polytitanates with a higher protonation degree is the ion-exchange chemical reaction. Low-cost protonated potassium polytitanates are promising to extract Li+ ions from aqueous solutions with a low concentration, as confirmed by the analysis of the results.
Comparing the Mental Wellbeing and Quality of Working Life among Nurses and Social Care Workers in the UK and Japan in Older Adults’ Care Services during the COVID-19 Pandemic
Authors: Neill Ruth D. , Wake Junko , Ohwa Mie , Manthorpe Jill , Gillen Patricia , McFadden Paula
Published: November 2022

This study explored and compared the psychological wellbeing, burnout, coping strategies and work-related quality of life amongst health and social care workers in older adults’ care homes and community settings during the COVID-19 pandemic in the United Kingdom (UK) and Japan. A cross-sectional online survey was conducted in the UK (May–July 2021) and a postal survey conducted in Japan (September–October 2021). Participants recruited were health and social care professionals within nursing, social care and social work occupations working in care home or community settings in the UK and Japan during the pandemic. Data were analysed using SPSS. 1327 respondents across the UK and Japan completed the survey. Respondents’ psychological wellbeing was significantly lower in Japan compared to the UK (p ≤ 0.001). UK respondents had significantly higher personal burnout (p < 0.05) and work-related burnout (p < 0.05) while those in Japan had significantly higher client-related burnout (p < 0.001). The novelty of this study relates to exploring mental wellbeing and quality of working life in two culturally contrasting countries. The overall psychological wellbeing and work-related quality of life of staff who work with older adults in the UK and Japan during the COVID-19 pandemic were lower than the population norm. Greater support and flexible working conditions for this workforce are needed to reduce burnout by improving wellbeing and work-related quality of life.
Religion Applied to Government: Navigating Competing and Complementary Spheres of Power
Authors: Calfano Brian Robert , Umphres William
Published: November 2022

Our paper offers two broad areas of focus for those looking to engage in political advocacy informed by the insights of religious belief and practice. The first has to do with the ends of politics: what is politics for and what does it pursue? Religious traditions offer key guidance over these fundamental questions. The second regards the issues of where politics happens, who participates, and what participation looks like. These questions defy simple answers or pat solutions. Rather, they pose a constellation of issues that calls forth sincere efforts at citizenship. Drawing on insights from theologians, political theories, and contemporary political science, we offer a series of reflection points on the realms of spiritual and temporal power.
Techniques of the Supramundane: Physician-Monks’ Medical Skills during the Early Medieval China (220–589) in China
Authors: Wang Dawei
Published: November 2022

Hagiographical tales tell us that some Buddhist monks who lived during the Early Medieval China (220–589) possessed considerable medical skills. Some were proficient in foreign medicine, while others had mastery over traditional Chinese medicine. The outstanding medical practitioners among these monks included Yu Fakai 于法開, Zhi Facun 支法存, Sengshen 僧深, and Shi Daohong 釋道洪. In addition to having a background in traditional Chinese medicine, these individuals are said to have had access to foreign medical knowledge due to their status as monks. However, the literature on these physician-monks’ medical skills is limited, which is why the present paper aims to explore this matter further, especially by introducing and elaborating upon some modern Chinese research which has generally gone unnoticed in international scholarship. To this end, this paper critically analyzes various historical records detailing these monks’ lives. It shows that, in addition to having extraordinary medical skills, some of these physician-monks mastered methods to cure specific diseases (such as beriberi [jiaoqi bing 腳氣病] (This is the name of the disease in traditional Chinese Medicine. It refers to a disease characterized by numbness, soreness, weakness, contracture, swelling, or muscle withering in the legs and feet.)). It also shows that they were usually more accurate in syndrome differentiation, while the treatments they prescribed were unique. However, given the lack of information, further research is required to clarify how these physician-monks learned methods as well as the impact of their foreign medicine knowledge on their methods.
Municipal Solid Waste and Leachate Characterization in the Cairo Metropolitan Area
Authors: Hussieny Maged A. , Morsy Mohamed S. , Ahmed Mostafa , Elagroudy Sherien , Abdelrazik Mohamed H.
Published: November 2022

The composition of municipal solid waste (MSW) in the Cairo metropolitan area is investigated. The outputs of MSW sorting analysis at various locations in Cairo with different waste management schemes are presented. Organics (58–75%) and plastic waste (19–28%) are the main components of MSW in Cairo with a higher percentage of organics in landfills compared to dumpsites. The leachate quality is analyzed, and the analysis results indicate that the concentration of macro inorganic pollutants (NH4+, Na+, Ca2+, and Cl−) and heavy metals (e.g., Cd2+ and Zn2+) are exceeding the majority of values reported in the literature in various cities all over the world. There was no evidence of an effect of the recycling process on chloride concentration in leachate, while the concentration of iron was reduced. The variation of leachate quality with time for two samples collected from the same municipal solid waste landfill is presented. The first leachate sample is a two-year-old, and the second sample is a sixteen-year-old. There was a significant increase in the concentration of chloride, sodium, chromium, calcium, and magnesium. The implications of the leachate quality in Cairo on the longevity of barrier systems in an MSW landfill are discussed.
Rheumato at Day 1
Authors: Rothschild Bruce
Published: November 2022

The inaugural issue of Rheumato exhibits the gamut of phenomenology that is inherent to why we became rheumatologists: our reliance on fundamentals, the quest to decipher apparently disparate findings, problem solving, hypothesis formation as to mechanisms and relationships, assessing the applicability and adaptability of new technologies and exploring the validity of old concepts/perspectives, and constantly reviewing our perspectives and performance [...]
Corporate Social Responsibility in Terms of Sustainable Development: Financial Risk Management Implications
Authors: Matytsin Denis E. , Petrenko Yelena S. , Saveleva Nadezhda K.
Published: November 2022

The motivation for this study was a new context associated with the increased cyclical nature of the economy and, accordingly, the increased financial risks of the business, which complicated the implementation of corporate social responsibility. The purpose of the article is to explore the relationship of corporate social responsibility with the financial risks of the business and explain this relationship in terms of sustainable development (SDGs). The article contributes to the development of the concept of financial risks of the business by clarifying their connection with corporate social responsibility and substantiating the relationship between the financial risks of the business. Structural equation modeling (SEM) showed that in 2020–2021, financial risks have demonstrated a complex (in most cases negative) relationship with each other and a contradictory impact on corporate social responsibility. The complex systemic relationship between corporate social responsibility and financial risks of business from the point of view of sustainable development is substantiated. In the context of increased financial risks, by systematically implementing SDGs 8, 9, 11, and 12, responsible companies get the opportunity to restore and improve their position in the market. The significance of the findings for businesses is that they proposed the SDGs as a promising new benchmark for business financial risk management. This will allow responsible companies to find a new Pareto optimum in the current conditions of uncertainty and determine for themselves the preferred level of corporate social responsibility that contributes to the effective financial risks of business management in the long term.
Is Profit–Loss-Sharing Financing Matter for Islamic Bank’s Profitability? The Indonesian Case
Authors: Sutrisno Sutrisno , Widarjono Agus
Published: November 2022

Financing is the main source of Islamic bank income as a financial intermediary that will contribute to the bank’s profitability. There are two financing schemes, namely profit–loss-sharing financing and nonprofit–loss-sharing financing. The main purpose of this study is to analyze the impact of profit–loss-sharing financing on the Islamic bank’s profitability. We employ 31 Islamic commercial banks in Indonesia using quarterly data and spanning from 2016 Q1 to 2020 Q4. Dynamic panel regression using the two-step system GMM is applied. The results showed that profit–loss-sharing financing has a negative effect on profitability, suggesting that profit–loss financing discourages Islamic bank performance. Meanwhile, some control variables such as size and liquidity risk positively influence profitability and low efficiency, and financing quality negatively affects profitability. These findings have an important implication for Islamic banks. Islamic banks must conduct tight monitoring for PLS financing so that this ex-post scheme can encourage the performance of Islamic banks.
GNSS Urban Positioning with Vision-Aided NLOS Identification
Authors: Yao Hexiong , Dai Zhiqiang , Chen Weixiang , Xie Ting , Zhu Xiangwei
Published: November 2022

The global navigation satellite system (GNSS) has played an important role in a broad range of consumer and industrial applications. In particular, cities have become GNSS major application scenarios; however, GNSS signals suffer from blocking, reflection and attenuation in harsh urban environments, resulting in diverse received signals, e.g., non-line-of-sight (NLOS) and multipath signals. NLOS signals often cause severe deterioration in positioning, navigation, and timing (PNT) solutions, which should be identified and excluded. In this paper, we propose a vision-aided NLOS identification method to augment GNSS urban positioning. A skyward omnidirectional camera is installed on a GNSS antenna to collect omnidirectional images of the sky region. After being rectified, these images are processed for sky region segmentation, which is improved by leveraging gradient information and energy function optimization. Image morphology processing is further employed to smooth slender boundaries. After sky region segmentation, the satellites are projected onto the omnidirectional image, from which NLOS satellites are identified. Finally, the identified NLOS satellites are excluded from GNSS PNT estimation, promoting accuracy and stability. Practical test results show that the proposed sky region segmentation module achieves over 96% accuracy, and that completely accurate NLOS identification is achieved for the experimental images. We validate the performance of our method on public datasets. Compared with the raw measurements without screening, the vision-aided NLOS identification method enables improvements of 60.3%, 12.4% and 63.3% in the E, N, and U directions, respectively, as well as an improvement of 58.5% in 3D accuracy.
Self-Supervised Encoders Are Better Transfer Learners in Remote Sensing Applications
Authors: Calhoun Zachary D. , Lahrichi Saad , Ren Simiao , Malof Jordan M. , Bradbury Kyle
Published: November 2022

Transfer learning has been shown to be an effective method for achieving high-performance models when applying deep learning to remote sensing data. Recent research has demonstrated that representations learned through self-supervision transfer better than representations learned on supervised classification tasks. However, little research has focused explicitly on applying self-supervised encoders to remote sensing tasks. Using three diverse remote sensing datasets, we compared the performance of encoders pre-trained through both supervision and self-supervision on ImageNet, then fine-tuned on a final remote sensing task. Furthermore, we explored whether performance benefited from further pre-training on remote sensing data. Our experiments used SwAV due to its comparably lower computational requirements, as this method would prove most easily replicable by practitioners. We show that an encoder pre-trained on ImageNet using self-supervision transfers better than one pre-trained using supervision on three diverse remote sensing applications. Moreover, self-supervision on the target data alone as a pre-training step seldom boosts performance beyond this transferred encoder. We attribute this inefficacy to the lower diversity and size of remote sensing datasets, compared to ImageNet. In conclusion, we recommend that researchers use self-supervised representations for transfer learning on remote sensing data and that future research should focus on ways to increase performance further using self-supervision.
Do Solid Waste Landfills Really Affect Land Use Change? Answers Using the Weighted Environmental Index (WEI)
Authors: Rodrigo-Ilarri Javier , Rodrigo-Clavero María-Elena , Romero Claudia P. , Suárez-Romero Patricio
Published: November 2022

This research analyzes the impact on land use induced by urban solid waste landfills using the Weighted Environmental Index (WEI). The methodology used to analyze the environmental value of the landfill’s areas of influence is based on the analysis of the space-time variations of the WEI inside them. The application of this methodology allows identifying the areas where the environmental value has changed over time, providing a quantitative indicator that can be analyzed using statistical techniques. The methodology has been applied as a case study to analyze the influence over land use in all the municipal solid waste landfills currently in operation inside the Valencia Region (Spain). Results have been obtained using GIS techniques integrating the information provided by the Information System on Land Occupation in Spain land use database. Results show that, without exception, the environmental value of the territory has decreased in all the cases analyzed. WEI is a powerful tool for analyzing land use change over time, and its application allows for performing detailed statistical analyses leading to key conclusions about land use changes inside the landfill influence areas.
Evaluation of Wildfire Occurrences in Pakistan with Global Gridded Soil Properties Derived from Remotely Sensed Data
Authors: Rafaqat Warda , Iqbal Mansoor , Kanwal Rida , Weiguo Song
Published: November 2022

Wildfires are predicted to occur more frequently and intensely as a result of global warming, posing a greater threat to human society, terrestrial ecosystems, and the atmosphere. Most existing methods for monitoring wildfire occurrences are based either on static topographical information or weather-based indices. This work explored the advantages of a new machine learning-based ‘soil properties’ attribute in monitoring wildfire occurrence in Pakistan. Specifically, we used satellite observations during 2001–2020 to investigate the correlation at different temporal and spatial scales between wildfire properties (fire count, FC) and soil properties and classes (SoilGrids1km) derived from combination with local covariates using machine learning. The correlations were compared to that obtained with the static topographic index elevation to determine whether soil properties, such as soil bulk density, taxonomy, and texture, provide new independent information about wildfires. Finally, soil properties and the topographical indices were combined to establish multivariate linear regression models to estimate FC. Results show that: (1) the temporal variations of FC are negatively correlated with soil properties using the monthly observations at 1° grid and regional scales; and overall opposite annual cycles and interannual variations between and soil properties are observed in Pakistan; (2) compared to the other static variables such as elevation, soil properties shows stronger correlation with the temperate wildfire count in Northern Pakistan but weaker correlation with the wildfire properties in Southern Pakistan; and it is found that combining both types of indices enhances the explained variance for fire attributes in the two regions; (3) In comparison to linear regression models based solely on elevation, multivariate linear regression models based on soil properties offer superior estimates of FC.
High-Performance Segmentation for Flood Mapping of HISEA-1 SAR Remote Sensing Images
Authors: Lv Suna , Meng Lingsheng , Edwing Deanna , Xue Sihan , Geng Xupu , Yan Xiao-Hai
Published: November 2022

Floods are the among the most frequent and common natural disasters, causing numerous casualties and extensive property losses worldwide every year. Since flooding areas are often accompanied by cloudy and rainy weather, synthetic aperture radar (SAR) is one of the most powerful sensors for flood monitoring with capabilities of day-and-night and all-weather imaging. However, SAR images are prone to high speckle noise, shadows, and distortions, which affect the accuracy of water body segmentation. To address this issue, we propose a novel Modified DeepLabv3+ model based on the powerful extraction ability of convolutional neural networks for flood mapping from HISEA-1 SAR remote sensing images. Specifically, a lightweight encoder MobileNetv2 is used to improve floodwater detection efficiency, small jagged arrangement atrous convolutions are employed to capture features at small scales and improve pixel utilization, and more upsampling layers are utilized to refine the segmented boundaries of water bodies. The Modified DeepLabv3+ model is then used to analyze two severe flooding events in China and the United States. Results show that Modified DeepLabv3+ outperforms competing semantic segmentation models (SegNet, U-Net, and DeepLabv3+) with respect to the accuracy and efficiency of floodwater extraction. The modified model training resulted in average accuracy, F1, and mIoU scores of 95.74%, 89.31%, and 87.79%, respectively. Further analysis also revealed that Modified DeepLabv3+ is able to accurately distinguish water feature shape and boundary, despite complicated background conditions, while also retaining the highest efficiency by covering 1140 km2 in 5 min. These results demonstrate that this model is a valuable tool for flood monitoring and emergency management.
An Innovative Supervised Classification Algorithm for PolSAR Image Based on Mixture Model and MRF
Authors: Liu Mingliang , Deng Yunkai , Han Chuanzhao , Hou Wentao , Gao Yao , Wang Chunle , Liu Xiuqing
Published: November 2022

The Wishart mixture model is an effective tool for characterizing the statistical distribution of polarimetric synthetic aperture radar (PolSAR) data. However, due to the difficulty in determining the equivalent number of looks, the Wishart mixture model has some problems in terms of practicality. In addition, the flexibility of the Wishart mixture model needs to be improved for complicated scenes. To improve the practicality and flexibility, a new mixture model named the relaxed Wishart mixture model (RWMM) is proposed. In RWMM, the equivalent number of looks is no longer considered a constant for the whole PolSAR image but a variable that varies between different clusters. Next, an innovative algorithm named RWMM-Markov random field (RWMM-MRFt) for supervised classification is proposed. A new selection criterion for adaptive neighborhood systems is proposed in the algorithm to improve the classification performance. The new criterion makes effective use of PolSAR scattering information to select the most suitable neighborhood for each center pixel in PolSAR images. Three datasets, including one simulated image and two real PolSAR images, are utilized in the experiment. The maximum likelihood classification results demonstrate the flexibility of the proposed RWMM for modeling PolSAR data. The proposed selection criterion shows superior performance than the span-based selection criterion. Among the mixture model-based MRF classification algorithms, the proposed RWMM-MRFt algorithm has the highest classification accuracy, and the corresponding classification maps have better anti-noise performance.
Effects of Vegetation Change on Soil Erosion by Water in Major Basins, Central Asia
Authors: Qian Kaixuan , Ma Xiaofei , Wang Yonghui , Yuan Xiuliang , Yan Wei , Liu Yuan , Yang Xiuyun , Li Jiaxin
Published: November 2022

The uncertainties in soil erosion (SE) are further intensified by various factors, such as global warming, regional warming and humidification, and vegetation cover changes. Moreover, quantitative evaluations of SE in major basins of Central Asia (CA) under changing environments have rarely been conducted. This study conducted quantitative evaluation of SE in four major basins (Syr Darya Basin (SDB), Amu Darya Basin (ADB), Ili River Basin (IRB) and Tarim River Basin (TRB) using the Revised Universal Soil Loss Equation (RUSLE) and analyzed the main driving factors. SE quantities in the basins presented relatively consistent upward fluctuating trends from 1982 to 2017. Vegetation cover variation fluctuated significantly from 1982 to 2017. Specifically, vegetation cover decreased continuously in SDB, ADB, and IRB, but increased gradually in TRB. Pixels with positive spatial variation of vegetation mainly occurred around lakes and oases near rivers. The Normalized Difference Vegetation Index (NDVI) showed higher correlation with precipitation (80.5%) than with temperature (48.3%). During the study period, the area of arable land (AL) exhibited the largest change among all land use types in CA. Under long-term human activities, the proportion of NDVI of other land types converting to AL was the highest. In the structural equation model (SEM), precipitation, temperature, Shannon Diversity Index (SHDI), and NDVI strongly influenced SE. Overall, the major basins in CA were jointly affected by climate, human activities, and vegetation. Specifically, climatic factors exerted the strongest influence, followed by SHDI (human activities). SE was found to be relatively serious in ADB, SDB, and IRB, with SE in SDB even approaching that in the Loess Plateau. Under the background of global changes, appropriate water and land resource management and optimization configurations should be implemented in CA with reference to TRB in order to relieve local SE problems.
Comprehensive Analysis of the Object Detection Pipeline on UAVs
Authors: Varga Leon Amadeus , Koch Sebastian , Zell Andreas
Published: November 2022

An object detection pipeline comprises a camera that captures the scene and an object detector that processes these images. The quality of the images directly affects the performance of the object detector. Current works focus on independently improving the image quality or object detection models but neglect the importance of joint optimization of the two subsystems. This paper aims to tune the detection throughput and accuracy of existing object detectors in the remote sensing scenario by optimizing the input images tailored to the object detector. We empirically analyze the influence of two selected camera calibration parameters (camera distortion correction and gamma correction) and five image parameters (quantization, compression, resolution, color model, and additional channels) for these applications. For our experiments, we utilize three Unmanned Aerial Vehicle (UAV) data sets from different domains and a mixture of large and small state-of-the-art object detector models to provide an extensive evaluation of the influence of the pipeline parameters. Finally, we realize an object detection pipeline prototype on an embedded platform for a UAV and give a best practice recommendation for building object detection pipelines based on our findings. We show that not all parameters have an equal impact on detection accuracy and data throughput. Using a suitable compromise between parameters, we can achieve higher detection accuracy for lightweight object detection models while keeping the same data throughput.
Evaluation of Urban Spatial Structure from the Perspective of Socioeconomic Benefits Based on 3D Urban Landscape Measurements: A Case Study of Beijing, China
Authors: Liu Yujia , Meng Qingyan , Zhang Jichao , Zhang Linlin , Allam Mona , Hu Xinli , Zhan Chengxiang
Published: November 2022

Urban spatial structures (USS) play an essential role in urbanization. Understanding the impact of USS patterns on their socioeconomic benefits is crucial to evaluating urban structure quality. Previous studies have, primarily, relied on statistical data and have significant temporal consistency and spatial accuracy limitations. Moreover, previous evaluation methods mainly determined the weight of indicators based on subjective assessments, such as the Delphi method, without integrating the actual socioeconomic benefits of complex urban systems. By measuring the two-dimensional (2D) urban functional landscape patterns and three-dimensional (3D) building forms of the city and considering the level of urban socioeconomic vitality as revealed by nighttime light intensity (NTLI), this study explores the influence of urban spatial structure on socioeconomic vitality. It provides a new perspective for evaluating the USS level. Furthermore, a comprehensive index, namely the Spatial Structure Socioeconomic Benefit Index (SSSBI), was constructed to quantify the socioeconomic benefits of USS. The results showed that (1) the impact of spatial structure on NTLI differs significantly with the distribution of urban functional landscape patterns and building forms. (2) The combined effect of any two spatial structure factors on NTLI was higher than the effect of each factor separately, indicating that multiple dimensions can improve urban spatial construction. (3) This study quantitatively extracts the characteristics of USS from multiple scales, which helps to find the optimal evaluation scale and build a scientific and objective evaluation model. The results showed that the USS assessment based on the SSSBI index is practical. This study could provide a reference for the government’s urban planning and land-use decisions.
Exploring the Environmental Conditions of Snow Particles Using Spaceborne Triple-Frequency Radar Measurements over Ocean
Authors: Yin Mengtao , Yuan Cheng
Published: November 2022

The environmental conditions of snow particles with different particle sizes and bulk effective densities over the ocean are explored using a coincidence dataset of National Aeronautics and Space Administration (NASA) CloudSat Cloud Profiling Radar (CPR) and Global Precipitation Mission (GPM) Dual-frequency Precipitation Radar (DPR). Observed triple-frequency radar signatures for snow particles over the ocean are firstly derived. Based on modeled triple-frequency signatures for various snow particles, DFR Ku/Ka and the ratio of DFR Ku/Ka to DFR Ku/W from observations are selected to indicate the snow particle size and bulk effective density, respectively. The dependences of two indicators on temperature, relative humidity and cloud liquid water content are presented. The snow particle size range becomes wider at warmer temperatures, higher relative humidities or lower cloud liquid water contents. At cold temperatures, low relative humidities or high cloud liquid water contents, large snow particles are prevalent. At high cloud liquid water contents, the riming process mainly contributes to the increase in snow particle bulk effective density. When supersaturation occurs, a large portion of snow particles have large sizes and low bulk effective densities at cold temperatures. This study can improve the understanding of snow microphysics and demonstrate the potential of spaceborne radar measurements in global snowfall retrievals.
A Polyimide Film-Based Simple Force Plate for Measuring the Body Mass of Tiny Insects
Authors: Shimazaki Kenichiro , Sugimoto Takumi , Toda Hirofumi , Takahashi Hidetoshi
Published: November 2022

Insects exhibit excellent maneuvers such as running and flying despite their small bodies; therefore, their locomotion mechanism is expected to provide a design guideline for micromachines. Numerical simulations have been performed to elucidate this mechanism, whereby it is important to develop a model that is physically identical to the target insect’s parts to reproduce kinematic dynamics. In particular, in flight, the shape and mass of wings, which flap at high frequencies, are significant parameters. However, small insects such as fruit flies have small, thin, and light wings; thus, their mass cannot be easily measured. In this study, we proposed a high-resolution and simple force plate to measure the mass of each part of a tiny insect. The device consists of a circular plate supported by flat spiral springs made of polyimide film, and a laser displacement meter that detects the displacement of the center of the plate. The simple plate fabrication process requires only a couple of minutes. A fabricated force plate with a sub-N/m spring constant achieved a resolution of less than 2 µg. As a demonstration, the wing mass of the fruit flies was measured. The experimental results suggest that the wings accounted for approximately 0.4% of the body mass.