bluuebunny/crossref_metadata_2025 huggingface dataset:
An Artificial MnWO4 Cathode Electrolyte Interphase Enabling Enhanced Electrochemical Performance of δ-MnO2 Cathode for Aqueous Zinc Ion Battery
Authors: Tian Hao , Zhang Huanlin , Zuo You , Ling Lei , Meng Tengfei , Zhang Hang , Sun Xiaohong , Cai Shu
Published: April 2023

The dissolution of active material in aqueous batteries can lead to a rapid deterioration in capacity, and the presence of free water can also accelerate the dissolution and trigger some side reactions that affect the service life of aqueous batteries. In this study, a MnWO4 cathode electrolyte interphase (CEI) layer is constructed on a δ-MnO2 cathode by cyclic voltammetry, which is effective in inhibiting the dissolution of Mn and improving the reaction kinetics. As a result, the CEI layer enables the δ-MnO2 cathode to produce a better cycling performance, with the capacity maintained at 98.2% (vs. activated capacity at 500 cycles) after 2000 cycles at 10 A g−1. In comparison, the capacity retention rate is merely 33.4% for pristine samples in the same state, indicating that this MnWO4 CEI layer constructed by using a simple and general electrochemical method can promote the development of MnO2 cathodes for aqueous zinc ion batteries.
Parametric Optimization of a Truncated Conical Metal Hydride Bed Surrounded by a Ring of PCM for Heat Recovery
Authors: Mellouli Sofiene , Bouzgarrou Fatma , Alqahtani Talal , Algarni Salem , Ghachem Kaouther , Kolsi Lioua
Published: April 2023

Metal hydride (MH) hydrogen storage needs an external heat source to release the stored hydrogen. To enhance the thermal performance of MHs, the incorporation of phase change materials (PCM) is a way to preserve reaction heat. This work proposes a new MH-PCM compact disk configuration (i.e., a truncated conical MH bed surrounded by a PCM ring). An optimization method is developed to find the optimal geometrical parameters of the MH truncated cone, which is then compared to a basic configuration (i.e., a cylindrical MH surrounded by a PCM ring). Moreover, a mathematical model is developed and used to optimize the heat transfer in a stack of MH-PCM disks. The optimum geometric parameters found (bottom radius of 0.2, top radius of 0.75 and tilt angle of 58.24) allow the truncated conical MH bed to reach a faster heat transfer rate and a large surface area of higher heat exchange. Compared to a cylindrical configuration, the optimized truncated cone shape enhances the heat transfer rate and the reaction rate in the MH bed by 37.68%.
Design, Control and Stabilization of a Transformable Wheeled Fire Fighting Robot with a Fire-Extinguishing, Ball-Shooting Turret
Authors: Tanyıldızı Alper Kadir
Published: April 2023

In this study, a hybrid wheeled fire extinguisher robot has been created. The robot has a two-degrees-of-freedom (DoF) fire extinguisher gun turret. To control the disruptive effect of mechanical oscillations on the firing system during movement of the robot body, PID and SMC controllers are used. When closed on flat ground, the robot’s five-piece transformable wheel construction allows it to travel swiftly. The wheel mechanism opens on tough terrain, allowing the wheel to assume a star-shaped configuration and enabling the robot to ascend by grasping onto obstructions. The three-dimensional mechanical design of the firefighter robot was designed first, followed by the kinematic model of the turret system and the three-dimensional Simscape model in the Matlab Simmechanic environment. Simulations of throwing fire-extinguishing balls at fire locations positioned at 20 m to 80 m horizontal and 1–30 m vertical distances were carried out on this model for three different scenarios (the robot is stationary, moving at constant speed and rotating around itself). The simulations resulted in a shooting success rate of 85.71% with PID and 95.23% with SMC (for a total of 105 shots). When the mistake rates were investigated, it was discovered that the constructed fire robot was usable in firefighting.
Optimal Selection of the Mother Wavelet in WPT Analysis and Its Influence in Cracked Railway Axles Detection
Authors: Zamorano Marta , Gómez María Jesús , Castejón Cristina
Published: April 2023

The detection of cracked railway axles by processing vibratory signals measured during operation is the focus of this study. The rotodynamic theory is applied to this specific purpose but, in practice and for real systems, there is no consensus on applying the results obtained from theory. Finding reliable patterns that change during operation would have advantages over other currently applied methods, such as non-destructive testing (NDT) techniques, because data between inspections would be obtained during operation. Vibratory signal processing techniques in the time-frequency domain, such as wavelet packet transform (WPT), have proved to be reliable to obtain patterns. The aim of this work is to develop a methodology to select the optimal function associated with the WPT, the mother wavelet (MW), and to find diagnostic patterns for cracked railway axle detection. In previous related works, the Daubechies 6 MW was commonly used for all speed/load conditions and defects. In this work, it was found that the Symlet 9 MW works better, so a comparative study was carried out with both functions, and it was observed that the success rates obtained with Daubechies 6 are improved when using Symlet 9. Specifically, defects above 16.6% of the shaft diameter were reliably detected, with no false alarms. To validate the proposed methodology, experimental vibratory signals of a healthy scaled railway axle were obtained and then the same axle was tested with a transverse crack located close to a section change (where this type of defect typically appears) for nine different crack depths.
Fatigue Life of a Comb Plate Expansion Joint
Authors: Li Yao , Lu Pengmin , Liu Chenyu , Ren Wei , Wen Jintang
Published: April 2023

Comb-plate expansion joints are widely used in bridge construction, and their failures are mainly static strength and fatigue. This paper used a new type of comb-plate expansion joint as the research object. Firstly, the finite element models (FEM) of the comb-plate expansion joint with minimum and maximum openings were established by Ansys software. Then, the equivalent stress, vertical deformation, and shear stress of the expansion joint under these two working conditions were checked with code. The results showed that the static strength of the expansion joints met the code requirements under both working conditions. Secondly, to investigate the service span of the comb-plate expansion joint, the fatigue life of the expansion joint was predicted using nCode DesignLife software, and the results showed that the minimum fatigue life of the expansion joint was 2.012 × 106 times, which is higher than the 2 × 106 times specified in the code. Finally, a fatigue test of 2 million times was carried out on the full-size expansion joint. Failure modes such as deformation, fracture, or breakage hardly appeared after the fatigue test, demonstrating the reliability of this new type of comb-plate expansion joint.
The Successive Approximation Genetic Algorithm (SAGA) for Optimization Problems with Single Constraint
Authors: Chen Zhihua , Xu Xuchen , Liu Hongbo
Published: April 2023

A limited feasible region restricts individuals from evolving optionally and makes it more difficult to solve constrained optimization problems. In order to overcome difficulties such as introducing initial feasible solutions, a novel algorithm called the successive approximation genetic algorithm (SAGA) is proposed; (a) the simple genetic algorithm (SGA) is the main frame; (b) a self-adaptive penalty function is considered and the penalty factor is adjusted automatically by the proportion of feasible and infeasible solutions; (c) a generation-by-generation approach and a three-stages evolution are introduced; and (d) dynamically enlarging and reducing the tolerance error of the constraint violation makes it much easier to generate initial feasible solutions. Then, ten benchmarks and an engineering problem were adopted to evaluate the SAGA in detail. It was compared with the improved dual-population genetic algorithm (IDPGA) and eight other algorithms, and the results show that SAGA finds the optimum in 5 s for an equality constraint and 1 s for an inequality constraint. The largest constraint violation can be accurate to at least three decimal fractions for most problems. SAGA obtains a better value, of 1.3398, than the eight other algorithms for the engineering problem. In conclusion, SAGA is very suitable for solving nonlinear optimization problems with a single constraint, accompanied by more accurate solutions, but it takes a longer time. In reality, SAGA searched for a better solution along the bound after several iterations and converged to an acceptable solution in early evolution. It is critical to improve the running speed of SAGA in the future.
FP-Conv-CM: Fuzzy Probabilistic Convolution C-Means
Authors: El Moutaouakil Karim , Palade Vasile , Safouan Safaa , Charroud Anas
Published: April 2023

Soft computing models based on fuzzy or probabilistic approaches provide decision system makers with the necessary capabilities to deal with imprecise and incomplete information. Hybrid systems based on different soft computing approaches with complementary qualities and principles have also become popular. On the one hand, fuzzy logic makes its decisions on the basis of the degree of membership but gives no information on the frequency of an event; on the other hand, the probability informs us of the frequency of the event but gives no information on the degree of membership to a set. In this work, we propose a new measure that implements both fuzzy and probabilistic notions (i.e., the degree of membership and the frequency) while exploiting the ability of the convolution operator to combine functions on continuous intervals. This measure evaluates both the degree of membership and the frequency of objects/events in the design of decision support systems. We show, using concrete examples, the drawbacks of fuzzy logic and probability-based approaches taken separately, and we then show how a fuzzy probabilistic convolution measure allows the correction of these drawbacks. Based on this measure, we introduce a new clustering method named Fuzzy-Probabilistic-Convolution-C-Means (FP-Conv-CM). Fuzzy C-Means (FCM), Probabilistic K-Means (PKM), and FP-Conv-CM were tested on multiple datasets and compared on the basis of two performance measures based on the Silhouette metric and the Dunn’s Index. FP-Conv-CM was shown to improve on both metrics. In addition, FCM, PKM, and FP-Conv-CM were used for multiple image compression tasks and were compared based on three performance measures: Mean Square Error (MSE), Peak Signal-to-Noise Ratio (PSNR), and Structural SImilarity Index (SSIM). The proposed FP-Conv-CM method shows improvements in all these three measures as well.
Exploring Mycosporine-like Amino Acid UV-Absorbing Natural Products for a New Generation of Environmentally Friendly Sunscreens
Authors: Rosic Nedeljka , Climstein Mike , Boyle Glen M. , Thanh Nguyen Duy , Feng Yunjiang
Published: April 2023

Human skin needs additional protection from damaging ultraviolet radiation (UVR: 280–400 nm). Harmful UVR exposure leads to DNA damage and the development of skin cancer. Available sunscreens offer chemical protection from detrimental sun radiation to a certain extent. However, many synthetic sunscreens do not provide sufficient UVR protection due to the lack of photostability of their UV-absorbing active ingredients and/or the lack of ability to prevent the formation of free radicals, inevitably leading to skin damage. In addition, synthetic sunscreens may negatively affect human skin, causing irritation, accelerating skin aging and even resulting in allergic reactions. Beyond the potential negative effect on human health, some synthetic sunscreens have been shown to have a harmful impact on the environment. Consequently, identifying photostable, biodegradable, non-toxic, and renewable natural UV filters is imperative to address human health needs and provide a sustainable environmental solution. In nature, marine, freshwater, and terrestrial organisms are protected from harmful UVR through several important photoprotective mechanisms, including the synthesis of UV-absorbing compounds such as mycosporine-like amino acids (MAAs). Beyond MAAs, several other promising, natural UV-absorbing products could be considered for the future development of natural sunscreens. This review investigates the damaging impact of UVR on human health and the necessity of using sunscreens for UV protection, specifically UV-absorbing natural products that are more environmentally friendly than synthetic UV filters. Critical challenges and limitations related to using MAAs in sunscreen formulations are also evaluated. Furthermore, we explain how the genetic diversity of MAA biosynthetic pathways may be linked to their bioactivities and assess MAAs’ potential for applications in human health.
Effect of the Mode of Fermentation on the Behavior of Penicillium bilaiae in Conditions of Abiotic Stress
Authors: Vassileva María , Martos Vanessa , del Moral Luis F. García , Vassilev Nikolay
Published: April 2023

The ability of a Penicillium bilaiae strain to support acid production and simultaneously solubilize inorganic sources of phosphate in conditions of submerged, solid-state fermentation (SSF) and immobilized cell system was examined in this study. Abiotic stress factors such as NaCl and different values of pH were introduced into the different fermentation process schemes to measure the fungal response. The results showed a higher tolerance of P. bilaiae when the fermentation process was carried out in solid-state and immobilized-cell conditions, which mimics the natural state of the soil microorganisms. The acidic culture conditions were not found to be suitable for fungal growth, which increased at a higher pH, with values of 4.0 and 6.0 being optimal for all types of fermentation. The presence of increasing amounts of NaCl provoked low biomass growth, titratable acidity, and simultaneous phosphate (P) solubilization. These results were, however, less pronounced at pH 4.0 and 6.0, particularly in conditions of SSF. Studying stress-tolerant microbial characteristics, particularly in different conditions and combinations of stress factors, is of great importance for further managing the overall microbial inoculants’ production and formulation process as well as their applications in specific soil–plant systems.
A Bacteriological Comparison of the Hemolymph from Healthy and Moribund Unionid Mussel Populations in the Upper Midwestern U.S.A. Prompts the Development of Diagnostic Assays to Detect Yokenella regensburgei
Authors: Leis Eric M. , Dziki Sara , Standish Isaac , Waller Diane , Richard Jordan , Weinzinger Jesse , Harris Cleyo , Knowles Susan , Goldberg Tony
Published: April 2023

Recent bacteriological investigations of freshwater mussel mortality events in the southeastern United States have identified a variety of bacteria and differences in bacterial communities between sick and healthy mussels. In particular, Yokenella regensburgei and Aeromonas spp. have been shown to be associated with moribund mussels, although it remains unclear whether these bacteria are causes or consequences of disease. To further understand the role of bacteria in mussel epizootics, we investigated mortality events that occurred in the upper Midwest in the Embarrass River (Wisconsin) and the Huron River (Michigan). For comparison, we also studied mussels from an unaffected population in the St. Croix River (Wisconsin). Diverse bacterial genera were identified from these sites, including Y. regensburgei from moribund mussels in the Embarrass River (Wisconsin). This bacterium has also been consistently isolated during ongoing mortality events in the Clinch River (Virginia). Subsequently, we developed and validated molecular assays for the detection of Yokenella to use in future investigations of mussel mortality events and to identify environmental reservoirs of this bacterium.
Characterization of a Riboflavin-Producing Mutant of Bacillus subtilis Isolated by Droplet-Based Microfluidics Screening
Authors: Xu Fan , Liu Chuan , Xia Miaomiao , Li Shixin , Tu Ran , Wang Sijia , Jin Hongxing , Zhang Dawei
Published: April 2023

Bacillus subtilis is one of the commonly used industrial strains for riboflavin production. High-throughput screening is useful in biotechnology, but there are still an insufficient number of articles focusing on improving the riboflavin production of B. subtilis by this powerful tool. With droplet-based microfluidics technology, single cells can be encapsulated in droplets. The screening can be carried out by detecting the fluorescence intensity of secreted riboflavin. Thus, an efficient and high-throughput screening method suitable for riboflavin production strain improvement could be established. In this study, droplet-based microfluidics screening was applied, and a more competitive riboflavin producer U3 was selected from the random mutation library of strain S1. The riboflavin production and biomass of U3 were higher than that of S1 in flask fermentation. In addition, the results of fed-batch fermentation showed that the riboflavin production of U3 was 24.3 g/L, an 18% increase compared with the parent strain S1 (20.6 g/L), and the yield (g riboflavin/100 g glucose) increased by 19%, from 7.3 (S1) to 8.7 (U3). Two mutations of U3 (sinRG89R and icdD28E) were identified through whole genome sequencing and comparison. Then they were introduced into BS168DR (parent of S1) for further analysis, which also caused riboflavin production to increase. This paper provides protocols for screening riboflavin-producing B. subtilis with droplet-based microfluidics technology and reveals mutations in riboflavin overproduction strains.
Chemico-Physical Properties of Some 1,1′-Bis-alkyl-2,2′-hexane-1,6-diyl-bispyridinium Chlorides Hydrogenated and Partially Fluorinated for Gene Delivery
Authors: Massa Michele , Rivara Mirko , Pertinhez Thelma A. , Compari Carlotta , Donofrio Gaetano , Cristofolini Luigi , Orsi Davide , Franceschi Valentina , Fisicaro Emilia
Published: April 2023

The development of very efficient and safe non-viral vectors, constituted mainly by cationic lipids bearing multiple charges, is a landmark for in vivo gene-based medicine. To understand the effect of the hydrophobic chain’s length, we here report the synthesis, and the chemico-physical and biological characterization, of a new term of the homologous series of hydrogenated gemini bispyridinium surfactants, the 1,1′-bis-dodecyl-2,2′-hexane-1,6-diyl-bispyridinium chloride (GP12_6). Moreover, we have collected and compared the thermodynamic micellization parameters (cmc, changes in enthalpy, free energy, and entropy of micellization) obtained by isothermal titration calorimetry (ITC) experiments for hydrogenated surfactants GP12_6 and GP16_6, and for the partially fluorinated ones, FGPn (where n is the spacer length). The data obtained for GP12_6 by EMSA, MTT, transient transfection assays, and AFM imaging show that in this class of compounds, the gene delivery ability strictly depends on the spacer length but barely on the hydrophobic tail length. CD spectra have been shown to be a useful tool to verify the formation of lipoplexes due to the presence of a “tail” in the 288–320 nm region attributed to a chiroptical feature named ψ-phase. Ellipsometric measurements suggest that FGP6 and FGP8 (showing a very interesting gene delivery activity, when formulated with DOPE) act in a very similar way, and dissimilar from FGP4, exactly as in the case of transfection, and confirm the hypothesis suggested by previously obtained thermodynamic data about the requirement of a proper length of the spacer to allow the molecule to form a sort of molecular tong able to intercalate DNA.
Simple Method for the Determination of THC and THC-COOH in Human Postmortem Blood Samples by Gas Chromatography—Mass Spectrometry
Authors: Álvarez-Freire Ivan , Valeiras-Fernández Anxa , Cabarcos-Fernández Pamela , Bermejo-Barrera Ana María , Tabernero-Duque María Jesús
Published: April 2023

A simple and sensitive analytical method was developed for qualitative and quantitative analysis of Δ9-tetrahydrocannabinol (Δ9-THC) and its metabolite 11-nor-Δ9-tetrahydrocannabinol-carboxylic acid (Δ9-THC-COOH) in human postmortem blood using gas chromatography/mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode. The method involved a liquid-liquid extraction in two steps, one for Δ9-THC and a second one for Δ9-THC-COOH. The first extract was analyzed using Δ9-THC-D3 as internal standard. The second extract was derivatized and analyzed using Δ9-THC-COOH-D3 as internal standard. The method was shown to be very simple, rapid, and sensitive. The method was validated for the two compounds, including linearity (range 0.05–1.5 µg/mL for Δ9-THC and 0.08–1.5 µg/mL for Δ9-THC-COOH), and the main precision parameters. It was linear for both analytes, with quadratic regression of calibration curves always higher than 0.99. The coefficients of variation were less than 15%. Extraction recoveries were superior to 80% for both compounds. The developed method was used to analyze 41 real plasma samples obtained from the Forensic Toxicology Service of the Institute of Forensic Sciences of Santiago de Compostela (Spain) from cases in which the use of cannabis was involved, demonstrating the usefulness of the proposed method.
Efficient Near-Infrared Luminescence Based on Double Perovskite Cs2SnCl6
Authors: Qing Xiaofei , Wu Chuanli , Han Xiuxun
Published: April 2023

Cs2SnCl6 double perovskite has attracted wide attention as a promising optoelectronic material because of its better stability and lower toxicity than its lead counterparts. However, pure Cs2SnCl6 demonstrates quite poor optical properties, which usually calls for active element doping to realize efficient luminescence. Herein, a facile co-precipitation method was used to synthesize Te4+ and Er3+-co-doped Cs2SnCl6 microcrystals. The prepared microcrystals were polyhedral, with a size distribution around 1–3 μm. Highly efficient NIR emissions at 1540 nm and 1562 nm due to Er3+ were achieved in doped Cs2SnCl6 compounds for the first time. Moreover, the visible luminescence lifetimes of Te4+/Er3+-co-doped Cs2SnCl6 decreased with the increase in the Er3+ concentration due to the increasing energy transfer efficiency. The strong and multi-wavelength NIR luminescence of Te4+/Er3+-co-doped Cs2SnCl6 originates from the 4f→4f transition of Er3+, which was sensitized by the spin-orbital allowed 1S0→3P1 transition of Te4+ through a self-trapped exciton (STE) state. The findings suggest that ns2-metal and lanthanide ion co-doping is a promising method to extend the emission range of Cs2SnCl6 materials to the NIR region.
New Energy Power System Dynamic Security and Stability Region Calculation Based on AVURPSO-RLS Hybrid Algorithm
Authors: Maihemuti Saniye , Wang Weiqing , Wu Jiahui , Wang Haiyun , Muhedaner Muladi , Zhu Qing
Published: April 2023

Using a high proportion of new energy is becoming the development trend of the modern power industry, with broad application prospects and potential threats to power system operation safety. This paper proposes a hybrid adaptive velocity update relaxation particle swarm optimization algorithm (AVURPSO) and recursive least square (RLS) method to quickly estimate the DSSR boundary using hyper-plane expression. Firstly, the operating point data in the high-dimension nodal injection space are analyzed using the AVURPSO algorithm to identify the key generators, equivalent search space, and critical points, which have relatively great effects on transient angle stability. The hyper-plane expression of the DSSR boundary, which matches the critical points best, is finally fitted by the RLS approach. Hence, the adopted algorithm is applied to rapidly approximate the DSSR boundary by hyper-plane expression in power injection spaces. Finally, the proposed algorithm is validated using a simulation case study on three wind farm regions of the actual Hami Power Grid of China using the DIgSILENT/Power Factory software. Consequently, the mentioned method effectively captures the security stability boundary of the new energy power system and realizes the three-dimensional visualization space of DSSR. By leveraging the DSSR, the state analysis can be conducted rapidly on several parameters, including security and stability assessments in relation to various energy supply capabilities. Meanwhile, these indices are calculated offline and applied online. The findings of this investigation confirm the efficacy and accuracy of the suggested modeling used in the analyzed system, offering technical assistance ensuring the stability of the new energy power system. The DSSR allows the rapid analysis of several parameters, including security and stability assessments with various energy supply capabilities.
Remote Sensing Temporal Reconstruction of the Flooded Area in “Tablas de Daimiel” Inland Wetland 2000–2021
Authors: Pena-Regueiro Jesús , Estornell Javier , Aguilar-Maldonado Jesús , Sebastiá-Frasquet Maria-Teresa
Published: April 2023

Tablas de Daimiel National Park (TDNP) is a unique inland wetland located in the Mancha plain (Spain). It is recognized at the international level, and it is protected by different figures, such as Biosphere Reserve. However, this ecosystem is endangered due to aquifer overexploitation, and it is at risk of losing its protection figures. The objective of our study is to analyze the evolution of the flooded area between the year 2000 and 2021 by Landsat (5, 7 and 8) and Sentinel-2 images, and to assess the TDNP state through an anomaly analysis of the total water body surface. Several water indices were tested, but the NDWI index for Sentinel-2 (threshold −0.20), the MNDWI for Landsat-5 (threshold −0.15), and the MNDWI for Landsat-8 (threshold −0.25) showed the highest accuracy to calculate the flooded surface inside the protected area’s limits. During the period 2015–2021, we compared the performance of Landsat-8 and Sentinel-2 and an R2 value of 0.87 was obtained for this analysis, indicating a high correspondence between both sensors. Our results indicate a high variability of the flooded areas during the analyzed period with significant peaks, the most notorious in the second quarter of 2010. Minimum flooded areas were observed with negative precipitation index anomalies since fourth quarter of 2004 to fourth quarter of 2009. This period corresponds to a severe drought that affected this region and caused important deterioration. No significant correlation was observed between water surface anomalies and precipitation anomalies, and the significant correlation with flow and piezometric anomalies was moderate. This can be explained because of the complexity of water uses in this wetland, which includes illegal wells and the geological heterogeneity.
A Novel Near-Surface Wave-Coherent Instantaneous Profiling System for Atmospheric Measurements
Authors: Stanek Mathew J. , Pastore Douglas M. , Hackett Erin E.
Published: April 2023

Large knowledge gaps concerning the effect of ocean surface waves on near-surface vertical distributions of temperature and humidity exist due to practical limitations and sensor fidelity challenges of direct measurements. Measurements of temperature and humidity are classically made using rocket- or radiosondes and fixed weather stations and can utilize a tethered profiling system. However, these measurement systems have limitations when obtaining wave-coherent measurements near the sea surface. Consequently, boundary layer similarity models are commonly employed to fill in near-surface measurement gaps despite the documented shortcomings of the models in this region. Thus, this manuscript presents a near-surface wave-coherent measurement platform that measures high-temporal-resolution vertical distributions of temperature and humidity down to ~0.3 m above the instantaneous sea surface. The design of the platform is described along with preliminary observations obtained during a pilot experiment. Ocean surface-wave phase-resolved vertical profiles are also demonstrated from the observations.
Assessing Regional Ecosystem Conditions Using Geospatial Techniques—A Review
Authors: Zhang Chunhua , Wang Kelin , Yue Yuemin , Qi Xiangkun , Zhang Mingyang
Published: April 2023

Ecosystem conditions at the regional level are critical factors for environmental management, public awareness, and land use decision making. Regional ecosystem conditions may be examined from the perspectives of ecosystem health, vulnerability, and security, as well as other conceptual frameworks. Vigor, organization, and resilience (VOR) and pressure–stress–response (PSR) are two commonly adopted conceptual models for indicator selection and organization. The analytical hierarchy process (AHP) is primarily used to determine model weights and indicator combinations. Although there have been many successful efforts in assessing regional ecosystems, they remain affected by a lack of spatially explicit data, weak integration of natural and human dimensions, and uncertain data quality and analyses. In the future, regional ecosystem condition assessments may be advanced by incorporating recent improvements in spatial big data and machine learning to create more operative indicators based on Earth observations and social metrics. The collaboration between ecologists, remote sensing scientists, data analysts, and scientists in other relevant disciplines is critical for the success of future assessments.
Maintenance Cost Minimization for an Agricultural Harvesting Gripper
Authors: Șerdean Florina Maria , Șerdean Mihai Dan , Mândru Silviu-Dan
Published: April 2023

A crucial aspect that has to be considered in all fields and, especially, in smart farming, a rapidly developing industry, is maintenance. Due to the costs generated by both under-maintaining and over-maintaining the components of a system, a balance has to be achieved. The paper is focused on presenting an optimal maintenance policy used to ensure cost minimization by determining the optimal time to make a preventive replacement of the actuators of a harvesting robotic system. First, a brief presentation of the gripper with Festo fluidic muscles used in a novel way instead of fingers is given. Then, the nature-inspired optimization algorithm, as well as the maintenance policy are described. The paper also includes the steps and the obtained results of the developed optimal maintenance policy applied for the Festo fluidic muscles. The outcome of the optimization shows that a significant reduction in the costs is obtained if one performs a preventive replacement of the actuators a few days before the lifetime provided by the manufacturer and the lifetime estimated using a Weibull distribution.
Intelligent Warehouse in Industry 4.0—Systematic Literature Review
Authors: Tubis Agnieszka A. , Rohman Juni
Published: April 2023

The development of Industry 4.0 (I4.0) and the digitization and automation of manufacturing processes have created a demand for designing smart warehouses to support manufacturing processes. Warehousing is one of the fundamental processes in the supply chain, and is responsible for handling inventory. Efficient execution of warehouse operations often determines the effectiveness of realized goods flows. Therefore, digitization and its use in exchanging information between partners, especially real-time inventory levels, is critical. For this reason, the digital solutions of Industry 4.0 have quickly found application in internal logistics processes and enabled the design of smart warehouses, also known as Warehouse 4.0. The purpose of this article is to present the results of the conducted review of publications on the design and operation of warehouses using the concepts of Industry 4.0. A total of 249 documents from the last 5 years were accepted for analysis. Publications were searched for in the Web of Science database using the PRISMA method. The article presents in detail the research methodology and the results of the biometric analysis. Based on the results, a two-level classification framework was proposed, which includes 10 primary categories and 24 subcategories. Each of the distinguished categories was characterized based on the analyzed publications. It should be noted that in most of these studies, the authors’ attention primarily focused on the implementation of (1) Industry 4.0 technological solutions, such as IoT, augmented reality, RFID, visual technology, and other emerging technologies; and (2) autonomous and automated vehicles in warehouse operations processes. Critical analysis of the literature also allowed us to identify the current research gaps, which will be the subject of further research by the authors.
TransFNN: A Novel Overtemperature Prediction Method for HVDC Converter Valves Based on an Improved Transformer and the F-NN Algorithm
Authors: Zhou Sihan , Qin Liang , Sun Hui , Peng Bo , Ruan Jiangjun , Wang Jing , Tang Xu , Wang Xiaole , Liu Kaipei
Published: April 2023

Appropriate cooling of the converter valve in a high-voltage direct current (HVDC) transmission system is highly significant for the safety, stability, and economical operation of a power grid. The proper adjustment of cooling measures is based on the accurate perception of the valve’s future overtemperature state, which is characterized by the valve’s cooling water temperature. However, very few previous studies have focused on this need, and the existing Transformer model, which excels in time-series predictions, cannot be directly applied to forecast the valve overtemperature state. In this study, we modified the Transformer and present a hybrid Transformer–FCM–NN (TransFNN) model to predict the future overtemperature state of the converter valve. The TransFNN model decouples the forecast process into two stages: (i) The modified Transformer is used to obtain the future values of the independent parameters; (ii) the relation between the valve cooling water temperature and the six independent operating parameters is fit, and the output of the Transformer is used to calculate the future values of the cooling water temperature. The results of the quantitative experiments showed that the proposed TransFNN model outperformed other models with which it was compared; with TransFNN being applied to predict the overtemperature state of the converter valves, the forecast accuracy was 91.81%, which was improved by 6.85% compared with that of the original Transformer model. Our work provides a novel approach to predicting the valve overtemperature state and acts as a data-driven tool for operation and maintenance personnel to use to adjust valve cooling measures punctually, effectively, and economically.
Continuous Non-Invasive Blood Pressure Measurement Using 60 GHz-Radar—A Feasibility Study
Authors: Vysotskaya Nastassia , Will Christoph , Servadei Lorenzo , Maul Noah , Mandl Christian , Nau Merlin , Harnisch Jens , Maier Andreas
Published: April 2023

Blood pressure monitoring is of paramount importance in the assessment of a human’s cardiovascular health. The state-of-the-art method remains the usage of an upper-arm cuff sphygmomanometer. However, this device suffers from severe limitations—it only provides a static blood pressure value pair, is incapable of capturing blood pressure variations over time, is inaccurate, and causes discomfort upon use. This work presents a radar-based approach that utilizes the movement of the skin due to artery pulsation to extract pressure waves. From those waves, a set of 21 features was collected and used—together with the calibration parameters of age, gender, height, and weight—as input for a neural network-based regression model. After collecting data from 55 subjects from radar and a blood pressure reference device, we trained 126 networks to analyze the developed approach’s predictive power. As a result, a very shallow network with just two hidden layers produced a systolic error of 9.2±8.3 mmHg (mean error ± standard deviation) and a diastolic error of 7.7±5.7 mmHg. While the trained model did not reach the requirements of the AAMI and BHS blood pressure measuring standards, optimizing network performance was not the goal of the proposed work. Still, the approach has displayed great potential in capturing blood pressure variation with the proposed features. The presented approach therefore shows great potential to be incorporated into wearable devices for continuous blood pressure monitoring for home use or screening applications, after improving this approach even further.
Stray Light Analysis and Suppression of the Visible to Terahertz Integrated Cloud Detection Optical System
Authors: Jiang Haiwei , Niu Xinhua
Published: April 2023

The wide-spectrum integrated imaging method can simultaneously obtain the spectral information of different spectral bands of the same target, which is conducive to the realization of the high-precision detection of target characteristics, and can simultaneously obtain more comprehensive elements such as the structure, shape, and microphysical parameters of the cloud. However, for stray light, the same surface has different characteristics at different wavelengths, and a wider spectral band means more complex and diverse sources of stray light, which renders the analysis and suppression of stray light more difficult. In this work, according to the characteristics of the visible-to-terahertz integrated optical system design scheme, the influence of material surface treatment on stray light was studied; the stray light analysis and optimization of the whole link of light transmission were carried out. For the sources of stray light in different channels, targeted suppression measures such as front baffle, field stop, special structure baffle, and reflective inner baffle were adopted. The simulation results indicate that when the off-axis field of view was greater than 10°. The point source transmittance (PST) of the terahertz channel is on the order of 10−4, the visible and infrared channels are less than 10−5, and the final terahertz PST was on the order of 10−8, while visible and infrared channels were lower than 10−11. Here, we present a method for stray light suppression based on conventional surface treatments for broadband imaging systems.
A Sensing-Based Visualization Method for Representing Pressure Distribution in a Multi-Zone Building by Floor
Authors: Jing Jiajun , Lee Dong-Seok , Joe Jaewan , Kim Eui-Jong , Cho Young-Hum , Jo Jae-Hun
Published: April 2023

Airflow in a multi-zone building can be a major cause of pollutant transfer, excessive energy consumption, and occupants discomfort. The key to monitoring airflows and mitigating related problems is to obtain a comprehensive understanding of pressure relationships within the buildings. This study proposes a visualization method for representing pressure distribution within a multi-zone building by using a novel pressure-sensing system. The system consists of a Master device and a couple of Slave devices that are connected with each other by a wireless sensor network. A 4-story office building and a 49-story residential building were installed with the system to detect pressure variations. The spatial and numerical mapping relationships of each zone were further determined through grid-forming and coordinate-establishing processes for the building floor plan. Lastly, 2D and 3D visualized pressure mappings of each floor were generated, illustrating the pressure difference and spatial relationship between adjacent zones. It is expected that the pressure mappings derived from this study will allow building operators to intuitively perceive the pressure variations and the spatial layouts of the zones. These mappings also make it possible for operators to diagnose the differences in pressure conditions between adjacent zones and plan a control scheme for the HVAC system more efficiently.
A Double Fourier-Transform Imaging Algorithm for a 24 GHz FMCW Short-Range Radar
Authors: Cicchetti Renato , Pisa Stefano , Piuzzi Emanuele , Testa Orlandino
Published: April 2023

A frequency-modulated continuous-wave radar for short-range target imaging, assembling a transceiver, a PLL, an SP4T switch, and a serial patch antenna array, was realized. A new algorithm based on a double Fourier transform (2D-FT) was developed and compared with the delay and sum (DAS) and multiple signal classification (MUSIC) algorithms proposed in the literature for target detection. The three reconstruction algorithms were applied to simulated canonical cases evidencing radar resolutions close to the theoretical ones. The proposed 2D-FT algorithm exhibits an angle of view greater than 25° and is five times faster than DAS and 20 times faster than the MUSIC one. The realized radar shows a range resolution of 55 cm and an angular resolution of 14° and is able to correctly identify the positions of single and multiple targets in realistic scenarios, with errors lower than 20 cm.
Comparison of Adsorbents for Cesium and Strontium in Different Solutions
Authors: Fan Shengnan , Jiang Lu , Jia Zhiqian , Yang Yu , Hou Li’an
Published: April 2023

Adsorption is an effective method to remove cesium and strontium from a solution. Although a variety of adsorbents has been reported, it is difficult to compare their adsorption properties due to different experimental conditions (such as solution concentration, volume, composition, temperature, etc.). In this paper, a series of adsorbents for the adsorption of cesium and strontium (ammonium phosphomolybdate, Prussian blue, sabite, clinoptilolite, titanium silicate) were synthesized and characterized using XRD, IR and SEM, and their adsorption performance in mixed solution (containing Li, Na, K, Cs, Ca, Sr and Mg ions, 1 mmol L−1), artificial seawater and salt lake brine were studied under the same conditions; in addition, the adsorption mechanism was elucidated. The results showed that ammonium phosphomolybdate has the largest adsorption capacity for cesium in the mixed solution. In artificial seawater and salt lake brine, Prussian blue displays the highest cesium adsorption capacity and the best selectivity. The multi-adsorption mechanisms are beneficial to the selective adsorption of Prussian blue in complex solutions. These results are useful for choosing adsorbents for cesium and strontium in applications.
Blood Lactate and Maximal Lactate Accumulation Rate at Three Sprint Swimming Distances in Highly Trained and Elite Swimmers
Authors: Mavroudi Maria , Kabasakalis Athanasios , Petridou Anatoli , Mougios Vassilis
Published: April 2023

We examined the blood lactate response, in terms of the maximal post-exercise concentration (Lamax), time to reach Lamax, and maximal lactate accumulation rate (VLamax), to swimming sprints of 25, 35, and 50 m. A total of 14 highly trained and elite swimmers (8 male and 6 female), aged 14–32, completed the 3 sprints in their specialization stroke with 30 min of passive rest in between. The blood lactate was measured right before and continually (every minute) after each sprint to detect the Lamax. The VLamax, a potential index of anaerobic lactic power, was calculated. The blood lactate concentration, swimming speed, and VLamax differed between the sprints (p < 0.001). The Lamax was highest after 50 m (13.8 ± 2.6 mmol·L–1, mean ± SD throughout), while the swimming speed and VLamax were highest at 25 m (2.16 ± 0.25 m·s–1 and 0.75 ± 0.18 mmol·L–1·s–1). The lactate peaked approximately 2 min after all the sprints. The VLamax in each sprint correlated positively with the speed and with each other. In conclusion, the correlation of the swimming speed with the VLamax suggests that the VLamax is an index of anaerobic lactic power and that it is possible to improve performance by augmenting the VLamax through appropriate training. To accurately measure the Lamax and, hence, the VLamax, we recommend starting blood sampling one minute after exercise.
Assessing the Burden of Dengue during the COVID-19 Pandemic in Mexico
Authors: Lugo-Radillo Agustin , Mendoza-Cano Oliver , Trujillo Xóchitl , Huerta Miguel , Ríos-Silva Mónica , Guzmán-Esquivel José , Benites-Godínez Verónica , Bricio-Barrios Jaime Alberto , Ríos-Bracamontes Eder Fernando , Cárdenas-Rojas Martha I. , Cárdenas Yolitzy , Murillo-Zamora Efrén
Published: April 2023

The transmission of the dengue virus in Mexico has historically been high, and its burden during the COVID-19 pandemic is currently not well understood. Our objective was to assess the burden of dengue-related disability-adjusted life years (DALYs) between 2020 and 2022. We conducted a cross-sectional analysis of databases resulting from an epidemiological surveillance of vector-borne diseases and computed DALYs using the protocol of the Global Burden of Disease (GBD) study 2019. Our results showed that there were 218,807 incident cases of dengue during the study period, resulting in 951 deaths. The calculated DALYs (and their 95% confidence intervals) were 8121 (7897–8396), 4733 (4661–4820), and 8461 (8344–8605) in 2020, 2021, and 2022, respectively. The DALY rates (per 100,000) were 6.5 (6.3–6.6), 3.8 (3.7–3.9), and 6.7 (6.6–6.8), respectively. The rates for 2020 and 2022 were similar to the historical mean (6.4, p = 0.884), whereas the rate for 2021 was lower than the mean. Premature mortality (years of life lost, YLL) contributed to 91% of the total burden. Our findings suggest that dengue fever remained a significant cause of disease burden during the COVID-19 pandemic, especially in terms of premature mortality.
Anti-Toxoplasma gondii and Anti-Neospora caninum Antibodies in Urban Traction Equids in Northeast Brazil: Seroprevalence and Risk Factors
Authors: Costa Paulo Wbiratan Lopes , Oliveira Clarisse Silva Menezes , Bezerra Roberto Alves , Alvares Felipe Boniedj Ventura , Formiga Victor Hugo Alves Sousa , Martins Marianne Rachel Domiciano Dantas , Feitosa Thais Ferreira , Vilela Vinícius Longo Ribeiro
Published: April 2023

The aim of this study was to describe the prevalence of anti-T. gondii and anti-N. caninum antibodies in equids that carry out traction work in Northeastern Brazil, and to establish the potential risk factors associated with seropositivity for these agents. Blood samples were collected from 322 traction equids (horses, donkeys and mules) in urban areas of 16 municipalities in the State of Paraíba, Brazil. The samples were sent for serological diagnosis using the Immunofluorescence Antibody Test (IFAT). Epidemiological questionnaires were given to the owners to assess the possible risk factors associated with infections. It was observed that 13.7% (44/322, CI: 10.9–16.5) of the equids tested positive for anti-T. gondii antibodies and 5% (16/322, CI: 2.6–7.4) tested positive for anti-N. caninum antibodies. Conducting traction work for over four years was considered a risk factor associated with T. gondii infection (odds ratio: 6.050; CI: 4.38–8.54, p = 0.025). There were no risk factors associated with N. caninum infection. It was concluded that traction equids have a significant prevalence of anti-T. gondii and anti-N. caninum antibodies in urban areas in the State of Paraíba, with an identified risk factor for seropositivity for anti-T. gondii as conducting traction work for more than four years.