bluuebunny/crossref_metadata_2025 huggingface dataset:
Competition between Structural Relaxation and Crystallization in the Glass Transition Range of Random Copolymers
Authors: Schawe Jürgen E. K. , Wrana Claus
Published: August 2020

Structural relaxation in polymers occurs at temperatures in the glass transition range and below. At these temperatures, crystallization is controlled by diffusion and nucleation. A sequential occurrence of structural relaxation, nucleation, and crystallization was observed for several homopolymers during annealing in the range of the glass transition. It is known from the literature that all of these processes are strongly influenced by geometrical confinements. The focus of our work is copolymers, in which the confinements are caused by the random sequence of monomer units in the polymer chain. We characterize the influence of these confinements on structure formation and relaxation in the vicinity of the glass transition. The measurements were performed with a hydrogenated nitrile-butadiene copolymer (HNBR). The kinetics of the structural relaxation and the crystallization was measured using fast differential scanning calorimetry (FDSC). This technique was selected because of the high sensitivity, the fast cooling rates, and the high time resolution. Crystallization in HNBR causes a segregation of non-crystallizable segments in the macromolecule. This yields a reduction in mobility in the vicinity of the formed crystals and as a consequence an increased amount of so-called “rigid amorphous fraction” (RAF). The RAF can be interpreted as self-assembled confinements, which limit and control the crystallization. An analysis of the crystallization and the relaxation shows that the kinetic of both is identical. This means that the Kohlrausch exponent of relaxation and the Avrami exponent of crystallization are identical. Therefore, the crystallization is not controlled by nucleation but by diffusion and is terminated by the formation of RAF.
Transforming Marble Waste into High-Performance, Water-Resistant, and Thermally Insulative Hybrid Polymer Composites for Environmental Sustainability
Authors: Bakshi Payal , Pappu Asokan , Patidar Ravi , Gupta Manoj Kumar , Thakur Vijay Kumar
Published: August 2020

Marble waste is generated by marble processing units in large quantities and dumped onto open land areas. This creates environmental problems by contaminating soil, water, and air with adverse health effects on all the living organisms. In this work, we report on understanding the use of calcium-rich marble waste particulates (MPs) as economic reinforcement in recyclable polypropylene (PP) to prepare sustainable composites via the injection molding method. The process was optimized to make lightweight and high-strength thermally insulated sustainable composites. Physicochemical, mineralogical, and microscopic characterization of the processed marble waste particulates were carried out in detail. Composite samples were subsequently prepared via the injection molding technique with different filler concentrations (0%, 20%, 40%, 60%, and 80%) on weight fraction at temperatures of 160, 180, and 200 °C. Detailed analysis of the mechanical and thermal properties of the fabricated composites was carried out. The composites showed a density varying from 0.96 to 1.27 g/cm3, while the water absorption capacity was very low at 0.006%–0.034%. Marble waste particulates were found to considerably increase the tensile, as well as flexural, strength of the sustainable composites, which varied from 22.06 to 30.65 MPa and 43.27 to 58.11MPa, respectively, for the molding temperature of 160 °C. The impact strength of the sustainable composites was found to surge with the increment in filler concentration, and the maximum impact strength was recorded as 1.66 kJ/m2with 20% particulates reinforcement at a molding temperature of 200 °C. The thermal conductivity of the particulates-reinforced sustainable composites was as low as 0.23 Wm−1K−1 at a 200 °C molding temperature with 20% and 40% filler concentrations, and the maximum thermal conductivity was 0.48 Wm−1K−1 at a 160 °C molding temperature with 80% filler concentration. Our findings have shown a technically feasible option for manufacturing a lightweight composite with better mechanical and thermal properties using marble waste particulates as a potential civil infrastructural material.
Natural 3D-Printed Bioinks for Skin Regeneration and Wound Healing: A Systematic Review
Authors: Smandri Ali , Nordin Abid , Hwei Ng Min , Chin Kok-Yong , Abd Aziz Izhar , Fauzi Mh Busra
Published: August 2020

Three-dimensional bioprinting has rapidly paralleled many biomedical applications and assisted in advancing the printing of complex human organs for a better therapeutic practice. The objective of this systematic review is to highlight evidence from the existing studies and evaluate the effectiveness of using natural-based bioinks in skin regeneration and wound healing. A comprehensive search of all relevant original articles was performed based on prespecified eligibility criteria. The search was carried out using PubMed, Web of Science, Scopus, Medline Ovid, and ScienceDirect. Eighteen articles fulfilled the inclusion and exclusion criteria. The animal studies included a total of 151 animals with wound defects. A variety of natural bioinks and skin living cells were implanted in vitro to give insight into the technique through different assessments and findings. Collagen and gelatin hydrogels were most commonly used as bioinks. The follow-up period ranged between one day and six weeks. The majority of animal studies reported that full wound closure was achieved after 2–4 weeks. The results of both in vitro cell culture and in vivo animal studies showed the positive impact of natural bioinks in promoting wound healing. Future research should be focused more on direct the bioprinting of skin wound treatments on animal models to open doors for human clinical trials.
Theoretical and Numerical Analysis of Mechanical Behaviors of a Metamaterial-Based Shape Memory Polymer Stent
Authors: Liu Ruoxuan , Xu Shuai , Luo Xiaoyu , Liu Zishun
Published: August 2020

Shape memory polymers (SMPs) have gained much attention in biomedical fields due to their good biocompatibility and biodegradability. Researches have validated the feasibility of shape memory polymer stent in treatment of vascular blockage. Nevertheless, the actual application of SMP stents is still in infancy. To improve the mechanical performance of SMP stent, a new geometric model based on metamaterial is proposed in this study. To verify the feasibility and mechanical behavior of this type of stent, buckling analysis, and in vivo expansion performance of SMP stent are simulated. Numerical results exhibit that stent of a smaller radius behaves a higher critical buckling load and smaller buckling displacement. Besides, a smaller contact area with vessel and smaller implanted stress are observed compared with traditional stents. This suggests that this SMP stent attributes to a reduced vascular restenosis. To characterize the radial strength of SMP stent, an analytical solution is derived by the assumption that the deformation of stent is mainly composed of bending and stretch. The radial strength of SMP stent is assessed in form of radial force. Analytical results reveal that radial strength is depended on the radius of stent and periodic numbers of unit cell in circumferential direction.
A Case Study of Polyether Ether Ketone (I): Investigating the Thermal and Fire Behavior of a High-Performance Material
Authors: Ramgobin Aditya , Fontaine Gaëlle , Bourbigot Serge
Published: August 2020

The thermal and fire behaviors of a high-performance polymeric material—polyether ether ketone (PEEK) was investigated. The TG plots of PEEK under different oxygen concentrations revealed that the initial step of thermal decomposition does not greatly depend on the oxygen level. However, oxygen concentration plays a major role in the subsequent decomposition steps. In order to understand the thermal decomposition mechanism of PEEK several methods were employed, i.e., pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS), thermogravimetric analysis (TGA) coupled with a Fourier-transform infrared spectrometer (FTIR). It was observed that the initial decomposition step of the material may lead to the release of noncombustible gases and the formation of a highly crosslinked graphite-like carbonaceous structure. Moreover, during the mass loss cone calorimetry test, PEEK has shown excellent charring and fire resistance when it is subjected to an incident heat flux of 50 kW/m². Based on the fire behavior and the identification of pyrolysis gases evolved during the decomposition of PEEK, the enhanced fire resistance of PEEK was assigned to the dilution of the flammable decomposition gases as well as the formation of a protective graphite-like charred structure during its decomposition. Moreover, at 60 kW/m², ignition occurred more quickly. This is because a higher rate of release of decomposition products is achieved at such a heat flux, causing a higher concentration of combustibles, thus an earlier ignition. However, the peak of heat release rate of the material did not exceed 125 kW/m².
A Small RO and MCDI Coupled Seawater Desalination Plant and Its Performance Simulation Analysis and Optimization
Authors: Yao Shouguang , Ji Mengting
Published: August 2020

To solve the problems of high specific energy consumption and excessive harmful ions in the water production of a small reverse osmosis (RO) plant, a desalination system coupling RO and membrane capacitive deionization (MCDI) is proposed in this study. Aiming at producing two cubic meters per day of fresh water with a salt concentration of less than 280 mg L−1, parameter matching optimization was carried out on two desalination system schemes of one-stage two-section RO and one-stage three-section RO coupled with MCDI. The results were compared with the parameter matching optimization results of the one-stage one-section RO and the one-stage two-section pure RO desalination system. The results show that compared with the pure RO desalination mode, the seawater desalination mode coupled with RO and MCDI reduces the specific energy consumption under the same effluent salt concentration. Moreover, it decreases the feed water pressure in front of the RO membrane, which can reduce the standard of high-pressure pump in a small seawater desalination plant. The energy consumption of the one-stage three-section RO and MCDI coupling system is lower than that of the one- stage two-section RO and MCDI coupling system, and the feed water pressure is also lower.
Design, Cost Estimation and Sensitivity Analysis for a Production Process of Activated Carbon from Waste Nutshells by Physical Activation
Authors: León Marcelo , Silva Javier , Carrasco Samuel , Barrientos Nelson
Published: August 2020

A conceptual design of an industrial production plant for activated carbon was developed to process 31.25 tons/day of industrial waste nutshells as the raw material and produce 6.6 ton/day of activated carbon using steam as an activation agent. The design considered the cost of the main equipment, the purchase price of the nutshells, basic services, and operation. A sensitivity analysis was developed, considering the price of the finished product and the volume of raw material processing varied up to ±25%. Furthermore, the total annual cost of the product was determined based on the production of 2100 tons/year of activated carbon. Two cash flows were developed and projected to periods of 10 years and 15 years of production, using a tax rate of 27%, a low discount rate (LDR) of 10% per year, and without external financing. For a 10-year production project, the net present value (NPV) was USD 2,785,624, the internal return rate (IRR) 21%, the return on investment (ROI) 25%, and the discounted payback period (DPP) after the fifth year. Considering a project with 15 years of production, the NPV was USD 4,519,482, the IRR at 23%, the ROI 24%, and the DPP after the fifth year of production.
Magnetic Nanoparticles of Fe3O4 Biosynthesized by Cnicus benedictus Extract: Photocatalytic Study of Organic Dye Degradation and Antibacterial Behavior
Authors: Ruíz-Baltazar Álvaro de Jesús , Méndez-Lozano Nestor , Larrañaga-Ordáz Daniel , Reyes-López Simón Yobanny , Zamora Antuñano Marco Antonio , Pérez Campos Ramiro
Published: August 2020

Currently, the use of sustainable chemistry as an ecological alternative for the generation of products or processes that are free of a polluting substance has assumed a preponderant role. The aim of this work is to propose a bioinspired, facile, low cost, non-toxic, and environmentally friendly alternative to obtaining magnetic nanoparticles with a majority phase of magnetite (Fe3O4). It is important to emphasize that the synthesis was based on the chemical reduction through the Cnicus benedictus extract, whose use as reducing agent has not been reported in the synthesis of iron oxides nanoparticles. In addition, the Cnicus benedictus is an abundant endemic plant in Mexico with several medicinal properties and a large number of natural antioxidants. The obtained nanoparticles exhibited significant magnetic and antibacterial properties and an enhanced photocatalytic activity. The crystallite size of the Fe3O4 nanoparticles (Fe3O4 NP’s) was calculated by the Williamson-Hall method. The photocatalytic properties of the Fe3O4 NP’s were studied by kinetics absorptions models in the Congo red (CR) degradation. Finally, the antibacterial effects of the Fe3O4 NPs were evaluated mediated the Kirby–Bauer method against Escherichia coli and Staphylococcus aureus bacteria. This route offers a green alternative to obtain Fe3O4 NPs with remarkable magnetic, photocatalytic, and antibacterial properties.
A Comparison of “Bottom-Up” and “Top-Down” Approaches to the Synthesis of Pt/C Electrocatalysts
Authors: Kuriganova Alexandra , Faddeev Nikita , Gorshenkov Mikhail , Kuznetsov Dmitri , Leontyev Igor , Smirnova Nina
Published: August 2020

Three 40 wt % Pt/C electrocatalysts prepared using two different approaches—the polyol process and electrochemical dispersion of platinum under pulse alternating current—and a commercial Pt/C catalyst (Johnson Matthey prod.) were examined via X-ray diffraction (XRD) and transmission electron microscopy (TEM). The stability characteristics of the Pt/C catalysts were studied via long-term cycling, revealing that, for all cycling modes, the best stability was achieved for the Pt/C catalyst with the largest platinum nanoparticle sizes, which was synthesized via electrochemical dispersion of platinum under pulse alternating current. Our results show that the mass and specific electrocatalytic activities of Pt/C catalysts toward ethanol electrooxidation are determined by the value of the electrochemically active Pt surface area in the catalysts.
A Study to Investigate the Mechanical Properties of Recycled Carbon Fibre/Glass Fibre-Reinforced Epoxy Composites Using a Novel Thermal Recycling Process
Authors: Karuppannan Gopalraj Sankar , Kärki Timo
Published: August 2020

Manufacturing-based carbon fibre-reinforced polymer (CFRP) and glass fibre-reinforced polymer (GFRP) wastes (pre-consumer waste) were recycled to recover valuable carbon fibres (CFs) and glass fibres (GFs), utilising a novel thermal recycling process with a cone calorimeter setup. The ideal conditions to recycle both the fibres occurred at 550 °C in atmospheric pressure. The processing time in the batch reactor to recycle CFs was 20–25 min, and to recycle GFs it was 25–30 min. The recovery rate of the recycled CFs was 95–98 wt%, and for GFs it was 80–82 wt%. Both the recycled fibres possessed a 100–110 mm average length. The resin phase elimination was verified by employing scanning electron microscopy (SEM). Furthermore, the fibres were manually realigned, compression moulded at room temperature, and cured for 24 h by a laminating epoxy resin system. The newly manufactured CFRP and GFRP composites were continuous (uniform length from end to end), unidirectionally oriented (0°), and non-woven. The composites were produced in two fibre volumes: 40 wt% and 60 wt%. The addition of ≈20 wt% recycled CFs increased the tensile strength (TS) by 12%, young modulus (YM) by 34.27% and impact strength (IS) by 7.26%. The addition of ≈20 wt% recycled GFs increased the TS by 75.14%, YM by 12.23% and the IS by 116.16%. The closed-loop recycling approach demonstrated in this study can effectively recycle both CFRP and GFRP manufacturing wastes. Preserving the structural integrity of the recycled fibres could be an advantage, enabling recycling for a specified number of times.
Terraforming Religious Consciousness: Race as a Signifier in New World Religious Cosmogony
Authors: Walker Malik J. M.
Published: August 2020

What is the connection between race and religious diversity? This question has emerged as particularly important in recent times, following heightened discussions on racial justice, equity, and the organization of society with regard to racial oppression. The terms race and religious diversity imply distinct points of contact that have within them diverse perspectives and worldviews, that carry with them assumed foundational understandings of the world and unexamined understandings of how the universe functions. This article explores the connection between race and religious diversity by discussing the physical and intellectual landscape and by raising concerns about the historical and religious-symbolic background of the Atlantic World. This background assumes the fact that the Atlantic World is more than just a historical phenomenon. Instead, the formation and operation of the Atlantic World reveals the construction of a cosmogony that informs racial (social/relational) and religious discourse (imagination/intellectual). The Atlantic World cosmogony arose from the conquest of the Americas by European interests, resulting in a terraforming process that adapted the New World to European sensibilities. The story of the Atlantic World cosmogony and the terraforming of the Americas serve as two points of reflection that call for assessing the connection of race and religious diversity. Concomitantly, considering the foreground of the Atlantic World cosmogony and terraforming opens the possibility of resituating the way we critically approach the discourse on race and religious diversity, allowing for communities to candidly express efforts to move beyond the history of the effects generated by the conquest of the Americas.
Islamic Education: An Islamic “Wisdom-Based Cultural Environment” in a Western Context
Authors: Lahmar Fella
Published: August 2020

As the number and types of Islamic schools in a Western context have increased, so too have the questions on their purpose and impact in pluralistic Western societies. Amid this increasingly complex environment, questions are raised, both internally and externally, to determine the nature of Islamic educational goals, schools’ knowledge and pedagogical practices. Analysis in this paper draws on multiple sources of data: classical and contemporary literature on education in Islam; the Department for Education (DfE) school census and the Office for Standards in Education; Children’s Services and Skills (Ofsted); and empirical case-study data extracted from the author’s PhD thesis on diversity in Islamic schools in Britain conducted during 2008–2012 and subsequently revised during 2018–2019 by following up emergent themes. This paper argues for a need to develop an “Islamic wisdom-based culture” promoting action (‘amal) which nurtures the holistic growth of learners in ethical areas (akhlāq), aesthetics (dhawq/jamāl) and develops a sense of freedom (huriyyah). By doing so, the paper draws primarily on Bennabi’s analysis of the role of culture (thaqāfah) in the civilisation cycle, Ibn-Khaldūn’s analysis of freedom and dignity in educational practice embedded in his discussion of the meanings of humanity) Al-insāniyyah) and Gadamer’s analysis of “practical wisdom”. Firstly, it contextualises Islamic schooling in Britain into a neoliberal pluralistic context. The wisdom inherent in Islamic education is explored through critical dialogue during the process of learning and action. The discussion then considers three key elements of “wisdom-based cultural environment” for Islamic education.
A New Weighting Method by Considering the Physical Characteristics of Atmospheric Turbulence and Decorrelation Noise in SBAS-InSAR
Authors: Duan Meng , Xu Bing , Li Zhiwei , Wu Wenhao , Cao Yunmeng , Liu Jihong , Wang Guanya , Hou Jingxin
Published: August 2020

Time series of ground subsidence can not only be used to describe motion produced by various anthropocentric and natural process but also to better understand the processes and mechanisms of geohazards and to formulate effective protective measures. For high-accuracy measurement of small baseline subset interferometric synthetic aperture radar (SBAS-InSAR), atmospheric turbulence and decorrelation noise are regarded as random variables and cannot be accurately estimated by a deterministic model when large spatio-temporal variability presents itself. Various weighting methods have been proposed and improved continuously to reduce the effects of these two parts and provide uncertainty information of the estimated parameters, simultaneously. Network-based variance-covariance estimation (NVCE) and graph theory (GT) are the two main weighting methods which were developed on the basis of previous algorithms. However, the NVCE weighting method only focuses on the influence of atmospheric turbulence and neglects the decorrelation noise. The GT method weights each interferogram in a time series by using the Laplace transformation. Although simple to implement, it is not reasonable to have an equal weight for each pixel in the same interferogram. To avoid these limitations, this study presents a new weighting method by considering the physical characteristics of atmospheric turbulence and decorrelation noise in SBAS-InSAR images. The effectiveness of the proposed method was tested and validated by using a set of simulated experiments and a case study on a Hawaiian island. According to the GPS-derived displacements, the average RMSE of the results from the new weighting method was 1.66 cm, indicating about an 8% improvement compared with 1.79, 1.80 and 1.80 cm from the unweighted method, the NVCE method and the GT method, respectively.
A Computational Workflow for Generating A Voxel-Based Design Approach Based on Subtractive Shading Envelopes and Attribute Information of Point Cloud Data
Authors: Alkadri Miktha Farid , De Luca Francesco , Turrin Michela , Sariyildiz Sevil
Published: August 2020

This study proposes a voxel-based design approach based on the subtractive mechanism of shading envelopes and attributes information of point cloud data in tropical climates. In particular, the proposed method evaluates a volumetric sample of new buildings based on predefined shading performance criteria. With the support of geometric and radiometric information stored in point cloud, such as position (XYZ), color (RGB), and reflection intensity (I), an integrated computational workflow between passive design strategy and 3D scanning technology is developed. It aims not only to compensate for some pertinent aspects of the current 3D site modeling, such as vegetation and surrounding buildings, but also to investigate surface characteristics of existing contexts, such as visible sun vectors and material properties. These aspects are relevant for conducting a comprehensively environmental simulation, while averting negative microclimatic impacts when locating the new building into the existing context. Ultimately, this study may support architects for taking decision-making in conceptual design stage based on the real contextual conditions.
Geodetic Study of the 2006–2010 Ground Deformation in La Palma (Canary Islands): Observational Results
Authors: Escayo Joaquín , Fernández José , Prieto Juan F. , Camacho Antonio G. , Palano Mimmo , Aparicio Alfredo , Rodríguez-Velasco Gema , Ancochea Eumenio
Published: August 2020

La Palma is one of the youngest of the Canary Islands, and historically the most active. The recent activity and unrest in the archipelago, the moderate seismicity observed in 2017 and 2018 and the possibility of catastrophic landslides related to the Cumbre Vieja volcano have made it strongly advisable to ensure a realistic knowledge of the background surface deformation on the island. This will then allow any anomalous deformation related to potential volcanic unrest on the island to be detected by monitoring the surface deformation. We describe here the observation results obtained during the 2006–2010 period using geodetic techniques such as Global Navigation Satellite System (GNSS), Advanced Differential Synthetic Aperture Radar Interferometry (A-DInSAR) and microgravimetry. These results show that, although there are no significant associated variations in gravity, there is a clear surface deformation that is spatially and temporally variable. Our results are discussed from the point of view of the unrest and its implications for the definition of an operational geodetic monitoring system for the island.
Climatology of Planetary Boundary Layer Height-Controlling Meteorological Parameters Over the Korean Peninsula
Authors: Allabakash Shaik , Lim Sanghun
Published: August 2020

Planetary boundary layer (PBL) height plays a significant role in climate modeling, weather forecasting, air quality prediction, and pollution transport processes. This study examined the climatology of PBL-associated meteorological parameters over the Korean peninsula and surrounding sea using data from the ERA5 dataset produced by the European Centre for Medium-range Weather Forecasts (ECMWF). The data covered the period from 2008 to 2017. The bulk Richardson number methodology was used to determine the PBL height (PBLH). The PBLH obtained from the ERA5 data agreed well with that derived from sounding and Global Positioning System Radio Occultation datasets. Significant diurnal and seasonal variability in PBLH was observed. The PBLH increases from morning to late afternoon, decreases in the evening, and is lowest at night. It is high in the summer, lower in spring and autumn, and lowest in winter. The variability of the PBLH with respect to temperature, relative humidity, surface pressure, wind speed, lower tropospheric stability, soil moisture, and surface fluxes was also examined. The growth of the PBLH was high in the spring and in southern regions due to the low soil moisture content of the surface. A high PBLH pattern is evident in high-elevation regions. Increasing trends of the surface temperature and accordingly PBLH were observed from 2008 to 2017.
N-Doped Reduced Graphene Oxide/Gold Nanoparticles Composite as an Improved Sensing Platform for Simultaneous Detection of Dopamine, Ascorbic Acid, and Uric Acid
Authors: Minta Daria , González Zoraida , Wiench Piotr , Gryglewicz Stanisław , Gryglewicz Grażyna
Published: August 2020

Gold nanoparticles (AuNPs) were homogeneously electrodeposited on nitrogen-doped reduced graphene oxide (N-rGO) to modify a glassy carbon electrode (GCE/N-rGO-Au) in order to improve the simultaneous detection of dopamine (DA), ascorbic acid (AA), and uric acid (UA). N-rGO was prepared by the hydrothermal treatment of graphene oxide (GO) and urea at 180 °C for 12 h. AuNPs were subsequently electrodeposited onto the surface of GCE/N-rGO using 1 mM HAuCl4 solution. The morphology and chemical composition of the synthesized materials were characterized by field-emission scanning electron microscopy and X-ray photoelectron spectroscopy. The electrochemical performance of the modified electrodes was investigated through cyclic voltammetry and differential pulse voltammetry measurements. Compared to GCE/rGO-Au, GCE/N-rGO-Au exhibited better electrochemical performance towards the simultaneous detection of the three analytes due to the more homogeneous distribution of the metallic nanoparticles as a result of more efficient anchoring on the N-doped areas of the graphene structure. The GCE/N-rGO-Au-based sensor operated in a wide linear range of DA (3–100 µM), AA (550–1500 µM), and UA (20–1000 µM) concentrations with a detection limit of 2.4, 58, and 8.7 µM, respectively, and exhibited satisfactory peak potential separation values of 0.34 V (AA-DA), 0.20 V, (DA-UA) and 0.54 V (AA-UA). Remarkably, GCE/N-rGO-Au showed a very low detection limit of 385 nM towards DA, not being susceptible to interference, and maintained 90% of its initial electrochemical signal after one month, indicating an excellent long-term stability.
Pine Cone Detection Using Boundary Equilibrium Generative Adversarial Networks and Improved YOLOv3 Model
Authors: Luo Ze , Yu Huiling , Zhang Yizhuo
Published: August 2020

The real-time detection of pine cones in Korean pine forests is not only the data basis for the mechanized picking of pine cones, but also one of the important methods for evaluating the yield of Korean pine forests. In recent years, there has been a certain number of detection accuracy for image processing of fruits in trees using deep-learning methods, but the overall performance of these methods has not been satisfactory, and they have never been used in the detection of pine cones. In this paper, a pine cone detection method based on Boundary Equilibrium Generative Adversarial Networks (BEGAN) and You Only Look Once (YOLO) v3 mode is proposed to solve the problems of insufficient data set, inaccurate detection result and slow detection speed. First, we use traditional image augmentation technology and generative adversarial network BEGAN to implement data augmentation. Second, we introduced a densely connected network (DenseNet) structure in the backbone network of YOLOv3. Third, we expanded the detection scale of YOLOv3, and optimized the loss function of YOLOv3 using the Distance-IoU (DIoU) algorithm. Finally, we conducted a comparative experiment. The experimental results show that the performance of the model can be effectively improved by using BEGAN for data augmentation. Under same conditions, the improved YOLOv3 model is better than the Single Shot MultiBox Detector (SSD), the faster-regions with convolutional neural network (Faster R-CNN) and the original YOLOv3 model. The detection accuracy reaches 95.3%, and the detection efficiency is 37.8% higher than that of the original YOLOv3.
Measuring the Normal Stress Distribution Acting on a Locked-Wheel of Push–Pull Locomotion Rovers via a Wheel Sensor System
Authors: Fujiwara Daisuke , Oshima Tetsuya , Iizuka Kojiro
Published: August 2020

The resistance force generated when the locked-wheel acts on the soil is critical for deciding the traveling performance of push–pull locomotion. The resistance force depends on the tangential force of the sliding soil wedge beneath the wheel, and the tangential force depends on the forces of the soil and the wheel perpendicular to the tangential direction. Hence, the normal stress distribution of the locked-wheel can affect the resistance force. Previous studies indicated different insights that describe either a uniform or non-uniform shape of the normal stress distribution. The distribution of the locked-wheel still needs to be examined experimentally. This study measured the normal stress distribution using the wheel sensor system, and the variation of the contact area and slip surface beneath the wheel were also observed in PIV analysis. Those results showed that the normal stress distribution was non-uniform along the wheel contact area, and the change of the distribution was confirmed with the change of the contact area and slip surface. Then, the resistance force calculated by a preliminary model based on the measured data was compared with the total resistance force of the wheel measured by a separate sensor. This comparison provided a theoretical consideration for the measured data.
A Comparison of Partial Discharge Sensors for Natural Gas Insulated High Voltage Equipment
Authors: Widger Phillip , Carr Daniel , Hills Meirion , Reid Alistair
Published: August 2020

The research in this paper consists of practical experimentation on a gas insulated section of high voltage equipment filled with carbon dioxide and technical air as a direct replacement to sulphur hexafluoride (SF6) and analyses the results of PD measurement by way of internal UHF sensors and external HFCTs. The results contribute to ongoing efforts to replace the global warming gas SF6 with an alternative such as pure carbon dioxide or technical air and are applicable to mixtures of electronegative gases that have a high content of buffer gas including carbon dioxide. The experiments undertaken involved filling a full-scale gas insulated line demonstrator with different pressures of CO2 or technical air and applying voltages up to 242 kV in both clean conditions and particle contaminated conditions. The results show that carbon dioxide and technical air can insulate a gas section normally insulated with SF6 at phase-to-earth voltage of 242 kV and that both HFCT and UHF sensors can be used to detect partial discharge with natural gases. The internal UHF sensors show the most accurate PD location results but external HFCTs offer a good compromise and very similar location accuracy.
Storm-Drain and Manhole Detection Using the RetinaNet Method
Authors: Santos Anderson , Marcato Junior José , de Andrade Silva Jonathan , Pereira Rodrigo , Matos Daniel , Menezes Geazy , Higa Leandro , Eltner Anette , Ramos Ana Paula , Osco Lucas , Gonçalves Wesley
Published: August 2020

As key-components of the urban-drainage system, storm-drains and manholes are essential to the hydrological modeling of urban basins. Accurately mapping of these objects can help to improve the storm-drain systems for the prevention and mitigation of urban floods. Novel Deep Learning (DL) methods have been proposed to aid the mapping of these urban features. The main aim of this paper is to evaluate the state-of-the-art object detection method RetinaNet to identify storm-drain and manhole in urban areas in street-level RGB images. The experimental assessment was performed using 297 mobile mapping images captured in 2019 in the streets in six regions in Campo Grande city, located in Mato Grosso do Sul state, Brazil. Two configurations of training, validation, and test images were considered. ResNet-50 and ResNet-101 were adopted in the experimental assessment as the two distinct feature extractor networks (i.e., backbones) for the RetinaNet method. The results were compared with the Faster R-CNN method. The results showed a higher detection accuracy when using RetinaNet with ResNet-50. In conclusion, the assessed DL method is adequate to detect storm-drain and manhole from mobile mapping RGB images, outperforming the Faster R-CNN method. The labeled dataset used in this study is available for future research.
Detection of Transmitted Power Violation Based on Geolocation Spectrum Database in Satellite-Terrestrial Integrated Networks
Authors: Yang Ning , Li Pinghui , Guo Daoxing , Zhang Linyuan , Ding Guoru
Published: August 2020

This paper investigates the detection of the transmitted power violation (TPV) in the satellite-terrestrial integrated network, where the terrestrial base station may break the spectrum policies so that severe damages are made to the satellite systems. Due to the lack of prior information on specific abnormal behaviors, this problem is complex and challenging. To tackle it, we first turn to the geolocation spectrum database based detecting framework, where not only the tasks of each segment but also the spectrum policies are specified. Then, the ternary hypothesis test and the generalized Neyman–Pearson (GMNP) test criterion are applied to maximize the detection probability under the false-alarm constraint. What is more, the Abnormal after Normal (AaN) detector is developed to simplify the analysis. Finally, simulations are conducted to demonstrate that the proposed detector can realize the detection of TPV in most cases at the expense of less than 10% detection probability.
Whole-Farm Revenue Protection as a Factor of Economic Stability in Crop Production
Authors: Kokot Željko , Marković Todor , Ivanović Sanjin , Meseldžija Maja
Published: August 2020

Crop production is largely unprotected and exposed to a great number of production factors. On the other hand, farmers are exposed to fluctuations in the market prices of their products every year, which often has a negative impact on the profits made. There are various risk management measures in plant production, and insurance is certainly one of the most effective instruments. One of the recent insurance models is Whole-Farm Revenue Insurance (WFRP), which is an American insurance model that has been applied since 2015. The essence of WFRP is to ensure that all crops on the farm are secured against production and market risks with only one policy. The aim of the research in this paper is to present WFRP as an entirely new model of revenue insurance on the example of a typical Serbian farm specializing in crop production. The WFRP model works by determining the insured revenue before the start of the production year. If at the end of the production year, for any reason, the realized revenue falls below the level of insured revenue, the farmer is entitled to indemnification. Due to the drought that hit the region where the analyzed farm is located, the yields were reduced, and thus the expected revenue was also reduced, and the farmer was entitled to damages of $5697. On the other hand, it is the farmer’s obligation to pay $373 to the insurer as a risk transfer fee. The authors proved that even such complex insurance models can be applied in countries such as Serbia, where awareness of the importance of insurance of agricultural production is still not developed.
New Opportunities for Work Integration in Rural Areas: The ‘Social Flavour’ of Craft Beer in Italy
Authors: Sforzi Jacopo , Colombo Laura A.
Published: August 2020

The last decade has seen a flourishing of social agriculture cooperatives and the exponential growth of the craft beer sector in Italy. Social microbreweries (social cooperatives that operate in the craft beer sector) have started emerging but have not yet been a focus of research. This paper explores the relationship between social agriculture and microbreweries in Italy, bridging the gap between social agricultural cooperation and craft beer production. It deploys a qualitative multiple case study methodology, based on the in-depth analysis of three case studies: Vecchia Orsa, one of the oldest social microbreweries in Italy; Pintalpina, which operates in a unique alpine setting; Articioc, established by a group of friends with a love of craft beer. This research suggests that the craft beer sector provides important opportunities for social innovation in social cooperatives, with a particular focus on the work integration of vulnerable people. In addition, this paper highlights different pathways for scaling social microbreweries, including focusing on organisational growth (growing the size of the business), scaling out (impacting greater numbers) and scaling deep (impacting cultural roots). Different scaling approaches are united by a common scaling strategy: network and partnership building. This emerges as an essential action to increase the impact of social microbreweries.
Estimation, and Framework Proposal of Greenhouse Gas Emissions of Fluorinated Substitutes for Ozone-Depleting Substances by Application Area in the Republic of Korea
Authors: Jung Kyuhong , Ro Donghoon , Park Young-Kwon
Published: August 2020

Since fluorine compounds have both high ozone depletion potential and high global warming potential, the study of hydrofluorocarbons (HFCs) and perfluorocarbons (PFCs) is crucial for climate change research. In this study, greenhouse gas (GHG) emissions from ozone-depleting industries in the Republic of Korea were estimated based on survey data on the use of fluorine compounds. This study is a response to the growing global attention to halocarbons that arose from the Kigali Amendment to the Montreal Protocol. Survey data on the consumption of fluorine compounds by application area were used to estimate emissions by applying the 2019 refinement IPCC Guidelines Tier 1a method. In addition, both the consumption ratio of fluorine compounds in the refrigeration and air conditioning application area and total fluorine compounds consumption by application area were compared with the values suggested by the UN Environment Programme to compare the current status with that in developing and developed countries. By comparing the derived GHG emissions with current emissions in the National Inventory Report, it was confirmed that 14,565 GgCO2eq of GHG emissions differed. In addition, through the replacement of fluorine compounds used as refrigerants, 14,422 GgCO2eq of the GHG emissions can be reduced.
Policy-Driven Sustainable Saline Drainage Disposal and Forage Production in the Western San Joaquin Valley of California
Authors: Singh Amninder , Quinn Nigel W. T. , Benes Sharon E. , Cassel Florence
Published: August 2020

Environmental policies to address water quality impairments in the San Joaquin River of California have focused on the reduction of salinity and selenium-contaminated subsurface agricultural drainage loads from westside sources. On 31 December 2019, all of the agricultural drainage from a 44,000 ha subarea on the western side of the San Joaquin River basin was curtailed. This policy requires the on-site disposal of all of the agricultural drainage water in perpetuity, except during flooding events, when emergency drainage to the River is sanctioned. The reuse of this saline agricultural drainage water to irrigate forage crops, such as ‘Jose’ tall wheatgrass and alfalfa, in a 2428 ha reuse facility provides an economic return on this pollutant disposal option. Irrigation with brackish water requires careful management to prevent salt accumulation in the crop root zone, which can impact forage yields. The objective of this study was to optimize the sustainability of this reuse facility by maximizing the evaporation potential while achieving cost recovery. This was achieved by assessing the spatial and temporal distribution of the root zone salinity in selected fields of ‘Jose’ tall wheatgrass and alfalfa in the drainage reuse facility, some of which have been irrigated with brackish subsurface drainage water for over fifteen years. Electromagnetic soil surveys using an EM-38 instrument were used to measure the spatial variability of the salinity in the soil profile. The tall wheatgrass fields were irrigated with higher salinity water (1.2–9.3 dS m−1) compared to the fields of alfalfa (0.5–6.5 dS m−1). Correspondingly, the soil salinity in the tall wheatgrass fields was higher (12.5 dS m−1–19.3 dS m−1) compared to the alfalfa fields (8.97 dS m−1–14.4 dS m−1) for the years 2016 and 2017. Better leaching of salts was observed in the fields with a subsurface drainage system installed (13–1 and 13–2). The depth-averaged root zone salinity data sets are being used for the calibration of the transient hydro-salinity computer model CSUID-ID (a one-dimensional version of the Colorado State University Irrigation Drainage Model). This user-friendly decision support tool currently provides a useful framework for the data collection needed to make credible, field-scale salinity budgets. In time, it will provide guidance for appropriate leaching requirements and potential blending decisions for sustainable forage production. This paper shows the tie between environmental drainage policy and the role of local governance in the development of sustainable irrigation practices, and how well-directed collaborative field research can guide future resource management.
Monthly Electric Load Forecasting Using Transfer Learning for Smart Cities
Authors: Jung Seung-Min , Park Sungwoo , Jung Seung-Won , Hwang Eenjun
Published: August 2020

Monthly electric load forecasting is essential to efficiently operate urban power grids. Although diverse forecasting models based on artificial intelligence techniques have been proposed with good performance, they require sufficient datasets for training. In the case of monthly forecasting, because just one data point is generated per month, it is not easy to collect sufficient data to construct models. This lack of data can be alleviated using transfer learning techniques. In this paper, we propose a novel monthly electric load forecasting scheme for a city or district based on transfer learning using similar data from other cities or districts. To do this, we collected the monthly electric load data from 25 districts in Seoul for five categories and various external data, such as calendar, population, and weather data. Then, based on the available data of the target city or district, we selected similar data from the collected datasets by calculating the Pearson correlation coefficient and constructed a forecasting model using the selected data. Lastly, we fine-tuned the model using the target data. To demonstrate the effectiveness of our model, we conducted an extensive comparison with other popular machine-learning techniques through various experiments. We report some of the results.
Availability of Public Electric Vehicle Charging Pile and Development of Electric Vehicle: Evidence from China
Authors: Wu Shuping , Yang Zan
Published: August 2020

As electric vehicles can significantly reduce the direct carbon emissions from petroleum, promoting the development of the electric vehicle market has been a new concentration for the auto industry. However, insufficient public charging infrastructure has become a significant obstacle to the further growth of electric vehicle sales. This paper estimates the impact of the availability of public charging piles on electric vehicle sales using panel regression analysis. It then investigates the barriers to the construction and operation of the public charging piles based on a field survey in 101 communities in Beijing, China. We find that insufficient public charging piles would significantly limit the sales of electric vehicles, in particular when the public charging piles are built up for specific users or in developed regions where private parking spaces are limited. It is found that the top four barriers are limited parking spaces, complicated circuit modification, unclear responsibilities for property management companies, and the objection or high mobility of existing parking space users.
Exploring the Spatial-Temporal Characteristics of Traditional Public Bicycle Use in Yancheng, China: A Perspective of Time Series Cluster of Stations
Authors: Gao Zhan , Wei Sheng , Wang Lei , Fan Sijia
Published: August 2020

Traditional dock-based public bicycle systems continue to dominate cycling in most cities, even though bicycle-sharing services are an increasingly popular means of transportation in many of China’s large cities. A few studies investigated the traditional public bicycle systems in small and mid-sized cities in China. The time series clustering method’s advantages for analyzing sequential data used in many transportation-related studies are restricted to time series data, thereby limiting applications to transportation planning. This study explores the characteristics of a typical third-tier city’s public bicycle system (where there is no bicycle-sharing service) using station classification via the time series cluster algorithm and bicycle use data. A dynamic time warping distance-based k-medoids method classifies public bicycle stations by using one-month bicycle use data. The method is further extended to non-time series data after format conversion. The paper identified three clusters of stations and analyzed the relationships between clusters’ features and the stations’ urban environments. Based on points-of-interest data, the classification results were validated using the enrichment factor and the proportional factor. The method developed in this paper can apply to other transportation analysis and the results also yielded relevant strategies for transportation development and planning.