bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancing the Strength and Ductility Synergy of Lightweight Ti-Rich Medium-Entropy Alloys through Ni Microalloying
Authors: Chen Po-Sung , Liu Jun-Rong , Tsai Pei-Hua , Liao Yu-Chin , Jang Jason Shian-Ching , Wu Hsin-Jay , Chang Shou-Yi , Chen Chih-Yen , Tsao I-Yu
Published: June 2024

Medium-entropy alloys (MEAs) have attracted considerable attention in recent decades due to their exceptional material properties and design flexibility. In this study, lightweight and non-equiatomic MEAs with low density (~5 g/cm3), high strength (yield strength: 1200 MPa), and high ductility (plastic deformation: ≧10%) were explored. We fine-tuned a previously developed Ti-rich MEA by microalloying it with small amounts of Ni (reducing the atomic radius and increasing the elastic modulus) through solid solution strengthening to achieve a series of MEAs with enhanced mechanical properties. Among the prepared MEAs, Ti65Ni1 and Ti65Ni3 exhibited optimal properties in terms of the balance between strength and ductility. Furthermore, the Ti65Ni3 MEA was subjected to thermo-mechanical treatment (TMT) followed by cold rolling 70% (CR70) and cold rolling 85% (CR85). Subsequently, the processed samples were rapidly annealed at 743 °C, 770 °C, 817 °C, and 889 °C at a heating rate of 15 °C/s. X-ray diffraction analysis revealed that the MEA could retain its single-body-centered cubic solid solution structure after TMT. Additionally, the tensile testing results revealed that increasing the annealing temperature led to a decrease in yield strength and an increase in ductility. Notably, the Ti65Ni3 MEA sample that was subjected to CR70 and CR85 processing and annealed for 30 s exhibited high yield strength (>1250 MPa) and ductility (>13%). In particular, the Ti65Ni3 MEA subjected to CR85 exhibited a specific yield strength of 264 MPa·cm3/g, specific tensile strength of 300 MPa·cm3/g, and ductility of >13%.
A Novel Nano-Laminated GdB2C2 with Excellent Electromagnetic Wave Absorption Performance and Ultra-High-Temperature Thermostability
Authors: Jiang Longfei , Qin Gang , Cui Pengxing , Wang Guoqing , Zhou Xiaobing
Published: June 2024

A novel nano-laminated GdB2C2 material was successfully synthesized using GdH2, B4C, and C via an in situ solid-state reaction approach for the first time. The formation process of GdB2C2 was revealed based on the microstructure and phase evolution investigation. Purity of 96.4 wt.% GdB2C2 was obtained at a low temperature of 1500 °C, while a nearly fully pure GdB2C2 could be obtained at a temperature over 1700 °C. The as-obtained GdB2C2 presented excellent thermal stability at a high temperature of 2100 °C in Ar atmosphere due to the stable framework formed by the high-covalence four-member and eight-member B-C rings in GdB2C2. The GdB2C2 material synthesized at 1500 °C demonstrated a remarkably low minimum reflection loss (RLmin) of −47.01 dB (3.44 mm) and a broad effective absorption bandwidth (EAB) of 1.76 GHz. The possible electromagnetic wave absorption (EMWA) mechanism could be ascribed to the nano-laminated structure and appropriate electrical conductivity, which facilitated good impedance matching, remarkable conduction loss, and interfacial polarization, along with the reflection and scattering of electromagnetic waves at multiple interfaces. The GdB2C2, with excellent EMWA performance as well as remarkable ultra-high-temperature thermal stability, could be a promising candidate for the application of EMWA materials in extreme ultra-high temperatures.
Design and Implementation of Electrochromic Smart Windows with Self-Driven Thermoelectric Power Generation
Authors: Xie Xiaohan , Ji Haining , Wang Lingcan , Wang Shaomei , Chen Qi , Luo Runteng
Published: June 2024

Electrochromic smart windows can achieve controllable modulation of color and transmittance under an external electric field with active light and thermal control capabilities, which helps reduce energy consumption caused by building cooling and heating. However, electrochromic smart windows often rely on external power circuits, which greatly affects the independence and portability of smart windows. Based on this, an electrochromic smart window driven by temperature-difference power generation was designed and implemented. This smart window provides automatic and manual control of the reversible cycle of electrochromic glass from light blue to dark blue according to user requirements and changes in the surrounding environment, achieving adaptive adjustment of visual comfort and reducing energy consumption. The infrared radiation rejection (from 780 to 2500 nm) of the electrochromic smart window is as high as 77.3%, and its transmittance (from 380 to 780 nm) fluctuates between 39.2% and 56.4% with changes in working state. Furthermore, the temperature in the indoor simulation device with electrochromic glass as the window was 15 °C lower than that with ordinary glass as the window after heating with a 250 W Philips infrared lamp for ten minutes. After 2000 cycles of testing, the performance of the smart window was basically maintained at its initial values, and it has broad application prospects in buildings, vehicles, and high-speed rail systems.
Pulse Proteins and Their Hydrolysates: A Comprehensive Review of Their Beneficial Effects on Metabolic Syndrome and the Gut Microbiome
Authors: Hong Lingyu , Fan Linlin , Wu Junchao , Yang Jiaqi , Hou Dianzhi , Yao Yang , Zhou Sumei
Published: June 2024

Pulses, as an important part of the human diet, can act as a source of high-quality plant proteins. Pulse proteins and their hydrolysates have shown promising results in alleviating metabolic syndrome and modulating the gut microbiome. Their bioactivities have become a focus of research, with many new findings added in recent studies. This paper comprehensively reviews the anti-hypertension, anti-hyperglycemia, anti-dyslipidemia and anti-obesity bioactivities of pulse proteins and their hydrolysates in recent in vitro and in vivo studies, which show great potential for the prevention and treatment of metabolic syndrome. In addition, pulse proteins and their hydrolysates can regulate the gut microbiome, which in turn can have a positive impact on the treatment of metabolic syndrome. Furthermore, the beneficial effects of some pulse proteins and their hydrolysates on metabolic syndrome have been supported by clinical studies. This review might provide a reference for the application of pulse proteins and their hydrolysates in functional foods or nutritional supplements for people with metabolic syndrome.
Long-Term Fasting-Induced Ketosis in 1610 Subjects: Metabolic Regulation and Safety
Authors: Grundler Franziska , Mesnage Robin , Ruppert Philip M. M. , Kouretas Demetrios , Wilhelmi de Toledo Françoise
Published: June 2024

Background: There is a growing consensus that fasting-induced ketosis has beneficial effects on human physiology. Despite these compelling benefits, fasting-induced ketosis raises concerns in some clinicians because it is often inappropriately compared with the pathologic uncontrolled ketone production in diabetic ketoacidosis. The determinants of the inter-individual differences in the intensity of ketosis during long-term fasting is unknown. Methods: We monitored daily variations in fasting ketonemia, as well as ketonuria, which is less invasive, in a large cohort of 1610 subjects, fasting between 4 and 21 days with the Buchinger Wilhelmi program, minimally supplemented with ~75–250 kcal (daily fruit juice, vegetable soup, and honey). Results: Ketonuria was detected in more than 95% of fasting subjects from day 4 onwards. Subjects consuming only soups, without fruit juice or honey, exhibited reduced caloric intake (72 kcal instead of 236 kcal) and carbohydrate intake (15.6 g instead of 56.5 g), leading to more intense ketonuria. Participants with high ketonuria were, in the majority, males, young, had a higher body weight, and had lower HDL-C and urea values. They had a larger decrease in blood glucose, glycated haemoglobin levels, body weight, and waist circumference. Furthermore, in the high-ketonuria group, a larger increase in blood uric acid concentration was observed. Conclusion: Our study showed that long-term fasting triggered ketosis, never reaching pathological levels, and that ketosis is influenced by age, gender, health, and the level of physical activity. Furthermore, it is modulated but not suppressed by minimal carbohydrate intake. Our study paves the way for better understanding how supplementation can modulate the therapeutic effects and tolerability of long-term fasting.
Experiences and Acceptability of a Weight Loss Intervention for Diabetes (Diabetes Remission Clinical Trial—DiRECT) in Aotearoa New Zealand: A Qualitative Study within a Pilot Randomised Controlled Trial
Authors: Campbell Kate , Peddie Meredith , Ashton Natalie , Ma’ia’i Kim , Russell-Camp Takiwai , Mann Jim , Camp Justine , Reynolds Andrew N.
Published: June 2024

The Diabetes Remission Clinical Trial (DiRECT) demonstrated that substantial weight loss and remission from type 2 diabetes can be achieved with low-energy total diet replacement and behavioural support. However, the acceptability of the DiRECT intervention in diverse populations with strong cultural emphases on food and shared eating remains unclear. We conducted a qualitative study nested within a pilot randomised controlled trial of DiRECT in one Māori (the Indigenous people of New Zealand) primary care provider in Aotearoa New Zealand. Participants with type 2 diabetes or prediabetes, obesity, and a desire to lose weight were randomised to either dietitian-supported usual care or the dietitian-supported DiRECT intervention for twelve months. The DiRECT intervention included three months of total diet replacement, then food reintroduction and supported weight loss maintenance. At three and twelve months, semi-structured interviews explored the acceptability of DiRECT and participants’ experiences of each intervention. Interview transcripts from 25 participants (aged 48 ± 10 years, 76% female, 78% Māori or Pacific) at three months and 15 participants at twelve months were analysed. Participants viewed their pre-enrolment selves as unhealthy people with poor eating habits and desired professional weight loss support. For DiRECT participants, the total diet replacement phase was challenging but well-received, due to rapid improvements in weight and health. Food reintroduction and weight loss maintenance each presented unique challenges requiring effective strategies and adaptability. All participants considered individualised and empathetic dietetic support crucial to success. Sociocultural factors influencing success were experienced in both interventions: family and social networks provided support and motivation; however, eating-related norms were identified as challenges. The DiRECT intervention was considered an acceptable approach to weight loss in participants with type 2 diabetes or prediabetes with strong cultural emphases on food and shared eating. Our findings highlight the importance of individualised and culturally relevant behavioural support for effective weight loss and weight loss maintenance.
Ganoderma lucidum Polysaccharides Ameliorate Acetaminophen-Induced Acute Liver Injury by Inhibiting Oxidative Stress and Apoptosis along the Nrf2 Pathway
Authors: Zhang Nan , Han Zhongming , Zhang Rui , Liu Linling , Gao Yanliang , Li Jintao , Yan Meixia
Published: June 2024

The excessive employment of acetaminophen (APAP) is capable of generating oxidative stress and apoptosis, which ultimately result in acute liver injury (ALI). Ganoderma lucidum polysaccharides (GLPs) exhibit hepatoprotective activity, yet the protective impact and potential mechanism of GLPs in relation to APAP-induced ALI remain ambiguous. The intention of this research was to scrutinize the effect of GLPs on APAP-induced ALI and to shed light on their potential mechanism. The results demonstrated that GLPs were capable of notably alleviating the oxidative stress triggered by APAP, as shown through a significant drop in the liver index, the activities of serum ALT and AST, and the amounts of ROS and MDA in liver tissue, along with an increase in the levels of SOD, GSH, and GSH-Px. Within these, the hepatoprotective activity at the high dose was the most conspicuous, and its therapeutic efficacy surpassed that of the positive drug (bifendate). The results of histopathological staining (HE) and apoptosis staining (TUNEL) indicated that GLPs could remarkably inhibit the necrosis of hepatocytes, the permeation of inflammatory cells, and the occurrence of apoptosis induced by APAP. Moreover, Western blot analysis manifested that GLPs enhanced the manifestation of Nrf2 and its subsequent HO-1, GCLC, and NQO1 proteins within the Nrf2 pathway. The results of qPCR also indicated that GLPs augmented the expression of antioxidant genes Nrf2, HO-1, GCLC, and NQO1. The results reveal that GLPs are able to set off the Nrf2 signaling path and attenuate ALI-related oxidative stress and apoptosis, which is a potential natural medicine for the therapy of APAP-induced liver injury.
Experimental Investigation of the Effect of Surfactant–Polymer Flooding on Enhanced Oil Recovery for Medium Crude Oil
Authors: Olabode Oluwasanmi , Dike Humphrey , Olaniyan Damilola , Oni Babalola , Faleye Michael
Published: June 2024

High technical and financial risks are involved in exploring and exploiting new fields; hence, greater focus has placed on the development of environmentally friendly, cost-effective, and enhanced oil recovery (EOR) options for existing fields. For reservoirs producing high-density crudes and those with high interfacial tensions, water flooding is usually less effective due to density differences—hence the advent of polymer and surfactant flooding. For cost-effective and eco-friendly EOR solutions, a biopolymer and a surfactant synthesized from Jatropha seeds are used in this study to determine their effectiveness in increasing the oil recovery during core flooding analysis. The experiment involved an initial water flooding that served as the base cases of three weight percentages of polymers and polymeric surfactant solutions. The results for the polymer flooding of 1 wt%, 1.5 wt%, and 2 wt% showed an incremental oil recovery in comparison to water flooding of 16.8%, 17%, and 26%, while the polymeric surfactant mixtures of 5 wt% of surfactant and 1 wt%, 1.5 wt%, and 2 wt% of a polymer recorded 16.5%, 22.3%, and 28.8%, and 10 wt% of surfactant and 1 wt%, 1.5 wt%, and 2 wt% of a polymer recorded incremental oil recoveries of 20%, 32.9%, and 38.8%, respectively.
Recent Advances in Nickel Catalysts with Industrial Exploitability for Copolymerization of Ethylene with Polar Monomers
Authors: Wang Ying , Lai Jingjing , Gao Rong , Gou Qingqiang , Li Bingyi , Zheng Gang , Zhang Randi , Yue Qiang , Song Zhihui , Guo Zifang
Published: June 2024

The direct copolymerization of ethylene with polar monomers to produce functional polyolefins continues to be highly appealing due to its simple operation process and controllable product microstructure. Low-cost nickel catalysts have been extensively utilized in academia for the synthesis of polar polyethylenes. However, the development of high-temperature copolymerization catalysts suitable for industrial production conditions remains a significant challenge. Classified by the resultant copolymers, this review provides a comprehensive summary of the research progress in nickel complex catalyzed ethylene-polar monomer copolymerization at elevated temperatures in the past five years. The polymerization results of ethylene–methyl acrylate copolymers, ethylene-tert–butyl acrylate copolymers, ethylene–other fundamental polar monomer copolymers, and ethylene–special polar monomer copolymers are thoroughly summarized. The involved nickel catalysts include the phosphine-phenolate type, bisphosphine-monoxide type, phosphine-carbonyl type, phosphine-benzenamine type, and the phosphine-enolate type. The effective modulation of catalytic activity, molecular weight, molecular weight distribution, melting point, and polar monomer incorporation ratio by these catalysts is concluded and discussed. It reveals that the optimization of the catalyst system is mainly achieved through the methods of catalyst structure rational design, extra additive introduction, and single-site catalyst heterogenization. As a result, some outstanding catalysts are capable of producing polar polyethylenes that closely resemble commercial products. To achieve industrialization, it is essential to further emphasize the fundamental science of high-temperature copolymerization systems and the application performance of resultant polar polyethylenes.
Effect of Graphene Oxide Addition on the Properties of Electrochemically Synthesized Polyaniline–Graphene Oxide Films
Authors: Balboa-Palomino Armando , Páramo-García Ulises , Melo-Banda José Aarón , Verde-Gómez José Ysmael , Gallardo-Rivas Nohra Violeta
Published: June 2024

In this work, the electrochemical synthesis of PANI and GO-modified PANI was performed using cyclic voltammetry, varying the amount of GO, 1 mg (PG1), 5 mg (PG5), and 10 mg (PG10) to analyze the effect of the amount of GO on the composite. PANI, PG1, PG5, and PG10 materials were characterized using optical microscopy, SEM, UV-vis, FTIR, Raman, and wettability. A stability test was also carried out by putting the materials to 500 oxidation-reduction cycles using cyclic voltammetry. The synthesis method allowed GO in PANI to be added through a chemical interaction between the two compounds. It was also found that the addition of GO led to an improvement in the hydrophilic character of the composite, which would lead to an improvement in the diffusion of reagents/species when the composites are used in aqueous media processes. The results of the stability test showed that the PG10 material presented a lower % loss of specific capacitance and energy compared with the other materials, which indicates that the GO presence (in the amount specified) improves the stability of the PANI. The PG10 material showed favorable and promising conditions for its use in fuel cell and battery processes.
Unsupervised Color-Based Flood Segmentation in UAV Imagery
Authors: Simantiris Georgios , Panagiotakis Costas
Published: June 2024

We propose a novel unsupervised semantic segmentation method for fast and accurate flood area detection utilizing color images acquired from unmanned aerial vehicles (UAVs). To the best of our knowledge, this is the first fully unsupervised method for flood area segmentation in color images captured by UAVs, without the need of pre-disaster images. The proposed framework addresses the problem of flood segmentation based on parameter-free calculated masks and unsupervised image analysis techniques. First, a fully unsupervised algorithm gradually excludes areas classified as non-flood, utilizing calculated masks over each component of the LAB colorspace, as well as using an RGB vegetation index and the detected edges of the original image. Unsupervised image analysis techniques, such as distance transform, are then applied, producing a probability map for the location of flooded areas. Finally, flood detection is obtained by applying hysteresis thresholding segmentation. The proposed method is tested and compared with variations and other supervised methods in two public datasets, consisting of 953 color images in total, yielding high-performance results, with 87.4% and 80.9% overall accuracy and F1-score, respectively. The results and computational efficiency of the proposed method show that it is suitable for onboard data execution and decision-making during UAV flights.
Anti-Jamming Imaging Method for Carrier-Free Ultra-Wideband Airborne SAR Based on Variational Modal Decomposition
Authors: Yuan Yue , Zhan Chengjin , Tian Wuqi , Chen Si , Zhang Shuning
Published: June 2024

This paper investigates the airborne synthetic aperture radar via outfield experiments based on carrier-free ultra-wideband signals with fifth-order Gaussian pulses with imaging using the backward projection algorithm. Typical blanket jamming is selected in the study, and NAM, NFM, and SFM are used as jamming signals to investigate the backward projection BP imaging effect of airborne synthetic aperture radar when subjected to blanket jamming in a real-world environment. Subsequently, a variational modal decomposition algorithm is proposed, aiming at the anti-jamming processing of airborne synthetic aperture radar. Further, the variational modal decomposition algorithms are compared with the empirical modal decomposition for the anti-jamming effect, which verified the effectiveness and high efficiency of the method. This study provides a new solution for the imaging problem of airborne synthetic aperture radar when subjected to blanket jamming, and a helpful reference is provided for the selection of anti-jamming processing methods.
A Hybrid Model Coupling Physical Constraints and Machine Learning to Estimate Daily Evapotranspiration in the Heihe River Basin
Authors: Li Xiang , Xue Feihu , Ding Jianli , Xu Tongren , Song Lisheng , Pang Zijie , Wang Jinjie , Xu Ziwei , Ma Yanfei , Lu Zheng , Wu Dongxing , Wei Jiaxing , He Xinlei , Zhang Yuan
Published: June 2024

Accurate estimation of surface evapotranspiration (ET) in the Heihe River Basin using remote sensing data is crucial for understanding water dynamics in arid regions. In this paper, by coupling physical constraints and machine learning for hybrid modeling, we develop a hybrid model based on surface conductance optimization. A hybrid modeling algorithm, two physical process-based ET algorithms (Penman–Monteith-based and Priestley–Taylor-based ET algorithms), and three pure machine learning algorithms (Random Forest, Extreme Gradient Boosting, and K Nearest Neighbors) are comparatively analyzed for estimating the ET. The results showed that, in general, the machine learning model optimized by parameters was able to better predict the surface conductance of the hybrid model. Driver analyses showed that radiation, normalized difference vegetation index (NDVI), and air temperature had high correlations with ET. The hybrid model had a better prediction performance for ET than the other five models, and it improved the R2 of the two physical process-based algorithms to 0.9, reduced the root mean square error (RMSE) to 0.5 mm/day, reduced the BIAS to 0.2 mm/day, and improved the Kling–Gupta efficiency (KGE) to 0.9. The hybrid model outperformed the others across different time scales, displaying lower BIAS, RMSE, and higher KGE. Spatially, its ET patterns aligned with regional vegetation changes, with superior accuracy in annual ET estimation compared to the other models. Comparison with other ET products shows that the estimation results based on the hybrid model have better performance. This approach not only improves the accuracy of ET estimation but also improves the understanding of the physical mechanism of ET estimation by pure machine learning models. This study can provide important support for understanding ET and hydrological processes under different climatic and biotic vegetation in other arid and semi-arid regions.
Spectral-Spatial Center-Aware Bottleneck Transformer for Hyperspectral Image Classification
Authors: Zhang Meng , Yang Yi , Zhang Sixian , Mi Pengbo , Han Deqiang
Published: June 2024

Hyperspectral image (HSI) contains abundant spectral-spatial information, which is widely used in many fields. HSI classification is a fundamental and important task, which aims to assign each pixel a specific class label. However, the high spectral variability and the limited labeled samples create challenges for HSI classification, which results in poor data separability and makes it difficult to learn highly discriminative semantic features. In order to address the above problems, a novel spectral-spatial center-aware bottleneck Transformer is proposed. First, the highly relevant spectral information and the complementary spatial information at different scales are integrated to reduce the impact caused by the high spectral variability and enhance the HSI’s separability. Then, the feature correction layer is designed to model the cross-channel interactions, thereby promoting the effective cooperation between different channels to enhance overall feature representation capability. Finally, the center-aware self-attention is constructed to model the spatial long-range interactions and focus more on the neighboring pixels that have relatively consistent spectral-spatial properties with the central pixel. Experimental results on the common datasets show that compared with the state-of-the-art classification methods, S2CABT has the better classification performance and robustness, which achieves a good compromise between the complexity and the performance.
Strain Measurement Technology and Precision Calibration Experiment Based on Flexible Sensing Fiber
Authors: Chen Bin , Yang Jun , Li Ang , Zhang Min , Li Jin , Wang Zhao
Published: June 2024

As the basic application of fiber optic sensing technology, strain measurement accuracy as a key index needs to be further calibrated and analyzed. In this paper, accuracy calibration experiments and the related analyses of two fiber-optic sensing technologies, the fiber-optic grating (FBG) and optical frequency domain reflectometry (OFDR), are carried out using a standard beam of equal strength and a mature resistive strain gauge (ESG). The fiber-optic single-point strain data for loading and unloading changes of the beams of equal strength show good continuity and linearity, with good cyclic stability, and the error in the strain test data is less than 2% after repeated loading. At the same time, using finite element theory to analyze the data and using the measured data error within 5%, a good strain test curve linearity is achieved and R2 is better than 0.998. After repeated loading and unloading tests, it is verified that the fiber grating and the distributed optical fiber in the strain test have good stability in repeatability accuracy. The calibration experiments and data analysis in this paper further illustrate the three sensing technologies in determining the strain test accuracy and the advantages and disadvantages of the indicators, and the development of the fiber optic sensing technology application provides basic technical support.
Advanced Applications of Porous Materials in Triboelectric Nanogenerator Self-Powered Sensors
Authors: Duan Zhengyin , Cai Feng , Chen Yuxin , Chen Tianying , Lu Peng
Published: June 2024

Porous materials possess advantages such as rich pore structures, a large surface area, low relative density, high specific strength, and good breathability. They have broad prospects in the development of a high-performance Triboelectric Nanogenerator (TENG) and self-powered sensing fields. This paper elaborates on the structural forms and construction methods of porous materials in existing TENG, including aerogels, foam sponges, electrospinning, 3D printing, and fabric structures. The research progress of porous materials in improving TENG performance is systematically summarized, with a focus on discussing design strategies of porous structures to enhance the TENG mechanical performance, frictional electrical performance, and environmental tolerance. The current applications of porous-material-based TENG in self-powered sensing such as pressure sensing, health monitoring, and human–machine interactions are introduced, and future development directions and challenges are discussed.
Longitudinal Mode Number Estimation of External Cavity Diode Laser Using Dual Periodic Grating for Optical Profiler System
Authors: Michihata Masaki , Goda Shuhei , Masui Shuzo , Takahashi Satoru
Published: June 2024

The concept of an optical profiler based on optical resonance was proposed, highlighting the initial requirements for mode number estimation. We proposed a method for estimating the longitudinal mode number of a laser propagating in an external cavity diode laser with high accuracy, utilizing dual-periodic diffraction gratings. These gratings were fabricated using interference lithography. To estimate the mode number, the wavelengths of two different modes are compared. Therefore, the greater the difference between the wavelengths, the higher the accuracy of the mode number determination. While the mode number difference was approximately 35 when using a conventional diffraction grating, this could be increased by a factor of 20 to around 700 using the dual-periodic grating. The relative accuracy achieved was 1.4 × 10−5.
The Piston Slap Force Reconstruction of Diesel Engine Using WOA-VMD and Deconvolution
Authors: Fan Shigong , Cai Yixi , Shi Yunxi , Zhang Zongzhen
Published: June 2024

In a diesel engine, piston slap commonly occurs concurrently with fuel combustion and serves as the main source of excitation. Although combustion pressure can be measured using sensors, determining the slap force is difficult without conducting tests. In this study, we propose a method to identify the slap force of the piston to solve this difficult problem. The traditional VMD algorithm easily receives noise interference, which affects the value of parameter combination [k, α] and thus affects the extraction accuracy of the algorithm. First, we obtain the transfer function between the incentive and vibration response through percussion tests. Secondly, a variational modal decomposition method based on whale algorithm optimization is used to separate the slap response from the surface acceleration of the block. Finally, we calculated the slap force using the deconvolution method. Deconvolution is a typical inverse problem of mathematics, often prone to ill-conditioning, and the singular value decomposition and regularization method is used to overcome this flaw and improve accuracy. The proposed method provides an important means to evaluate the angular distribution of the slap force, identify the shock positions on the piston liner, and determine the peak value of the waveform which helps us analyze the vibration characteristics of the piston and optimize the structural design of the engine.
An Improved Ningxia Desert Herbaceous Plant Classification Algorithm Based on YOLOv8
Authors: Ma Hongxing , Sheng Tielei , Ma Yun , Gou Jianping
Published: June 2024

Wild desert grasslands are characterized by diverse habitats, uneven plant distribution, similarities among plant class, and the presence of plant shadows. However, the existing models for detecting plant species in desert grasslands exhibit low precision, require a large number of parameters, and incur high computational cost, rendering them unsuitable for deployment in plant recognition scenarios within these environments. To address these challenges, this paper proposes a lightweight and fast plant species detection system, termed YOLOv8s-KDT, tailored for complex desert grassland environments. Firstly, the model introduces a dynamic convolutional KernelWarehouse method to reduce the dimensionality of convolutional kernels and increase their number, thus achieving a better balance between parameter efficiency and representation ability. Secondly, the model incorporates triplet attention into its feature extraction network, effectively capturing the relationship between channel and spatial position and enhancing the model’s feature extraction capabilities. Finally, the introduction of a dynamic detection head tackles the issue related to target detection head and attention non-uniformity, thus improving the representation of the target detection head while reducing computational cost. The experimental results demonstrate that the upgraded YOLOv8s-KDT model can rapidly and effectively identify desert grassland plants. Compared to the original model, FLOPs decreased by 50.8%, accuracy improved by 4.5%, and mAP increased by 5.6%. Currently, the YOLOv8s-KDT model is deployed in the mobile plant identification APP of Ningxia desert grassland and the fixed-point ecological information observation platform. It facilitates the investigation of desert grassland vegetation distribution across the entire Ningxia region as well as long-term observation and tracking of plant ecological information in specific areas, such as Dashuikeng, Huangji Field, and Hongsibu in Ningxia.
Compact Wideband Tapered Slot Antenna Using Fan-Shaped and Stepped Structures for Chipless Radio-Frequency-Identification Sensor Tag Applications
Authors: Yeo Junho , Lee Jong-Ig
Published: June 2024

In this paper, two kinds of miniaturization methods for designing a compact wideband tapered slot antenna (TSA) using either fan-shaped structures only or fan-shaped and stepped structures were proposed. First, a miniaturization method appending the fan-shaped structures, such as quarter circular slots (QCSs), half circular slots (HCSs), and half circular patches (HCPs), to the sides of the ground conductor for the TSA was investigated. The effects of appending the QCSs, HCSs, and HCPs sequentially on the input reflection coefficient and gain characteristics of the TSA were compared. The compact wideband TSA using the first miniaturization method showed the simulated frequency band for a voltage standing wave ratio (VSWR) less than 2 of 2.530–13.379 GHz (136.4%) with gain in the band ranging 3.1–6.9 dBi. Impedance bandwidth was increased by 29.7% and antenna size was reduced by 39.1%, compared to the conventional TSA. Second, the fan-shaped structures combined with the stepped structures (SSs) were added to the sides of the ground conductor to further miniaturize the TSA. The fan-shaped structures based on the HCSs and HCPs were appended to the ground conductor with the QCSs and SSs. The compact wideband TSA using the second miniaturization method had the simulated frequency band for a VSWR less than 2 of 2.313–13.805 GHz (142.6%) with gain in the band ranging 3.0–8.1 dBi. Impedance bandwidth was increased by 37.8% and antenna size was reduced by 45.9%, compared to the conventional TSA. Therefore, the increase in impedance bandwidth and the size reduction effect of the compact wideband TSA using the second miniaturization method were better compared to those using the first method. In addition, sidelobe levels at high frequencies decreased while gain at high frequencies increased. A prototype of the compact wideband TSA using the second miniaturization method was fabricated on an RF-35 substrate to validate the simulation results. The measured frequency band for a VSWR less than 2 was 2.320–13.745 GHz (142.2%) with measured gain ranging 3.1–7.9 dBi.
Biochars Derived from Olive Mill Byproducts: Typology, Characterization, and Eco-Efficient Application in Agriculture—A Systematic Review
Authors: Lustosa Filho José Ferreira , da Silva Ana Paula Ferreira , Costa Silvana Teixeira , Gomes Hélder Teixeira , de Figueiredo Tomás , Hernández Zulimar
Published: June 2024

In the context of climate change and the circular economy, biochar agricultural and environmental applications have attracted a good deal of attention. Biochar has unique characteristics like surface area, porosity, water-holding capacity, pH, surface charge, and nutrients. This study reviews the biochar production from olive pomace (OP) and olive stone (OS) byproducts, its chemical and physical characterization, and its environmental application. The current review highlights the conditions for biochar production, the effects of pyrolysis temperature, and feedstock type on the physicochemical properties of biochar. High pyrolysis temperature (>500 °C) promotes a high specific surface area, high porosity (especially for OS biochars), and pH as well as the content of ash and fixed carbon, but generates low cation exchange capacity (CEC) and electrical conductivity (EC) and high values of O/C and H/C ratio. OP biochar also presents a high C amount, and ash content, i.e., rich in nutrients and high alkalizing capacity. OP biochar serves as an important source of plant nutrients, especially potassium. After adding both types of biochar, aggregate stability and the amount of water held in soil increase, and bulk density and bioavailability of trace elements decrease. Thus, biochar from olive mill wastes can be a potential plant nutrient reservoir, a good amendment to improve soil properties and long-term carbon sequestration. Results presented in this review can be used to build designer biochars from olive mill wastes to help solve environmental issues (water purification and pollutant remediation) and are suitable for improving soil physical chemistry characteristics and crop growth.
Variations of Global Compound Temperature and Precipitation Events and Associated Population Exposure Projected by the CMIP6 Multi-Model Ensemble
Authors: Yang Yang , Yue Tianxiang
Published: June 2024

Compound climate events often pose greater harm to humans and society than single-variable climate issues. This study projects the temporal changes and spatial pattern evolution of four compound climate events (including warm–wet, warm–dry, cold–wet, and cold–dry) and the corresponding population exposure in global land under the shared socioeconomic pathway (SSP) 2–4.5 based on the Coupled Model Intercomparison Project phase 6 simulations. Results show the following: (1) The warm–wet event is significantly decreasing at a rate of 0.06 days per decade, while the cold–wet event is significantly increasing at a rate of 0.06 days per decade. The warm–dry event and cold–dry event show an upward trend but are not significant. (2) All four types of compound events will undergo mutations in the next 80 years, with the warm–dry event having the highest frequency of mutations. (3) West Asia is a high-risk area for warm–dry and cold–wet events. Northern Africa is a hot spot area for the warm–wet event, while Brazil is a hot spot area for the cold–dry event. (4) Areas with exposure levels (population under four compound climate events) of medium or higher are mainly distributed in East Asia, South Asia, and central Africa. When the population exposure exceeds 105 person · day, the area of population exposure to compound events related to dry conditions is greater than that of compound events related to wet conditions. This study has guiding significance for understanding, identifying, analyzing, and preventing compound extreme climate events in the context of global warming.
Economic Policies for the Sustainability Transition: Approaches, Outcomes and Prospects in the EU and China
Authors: Zoboli Roberto , Mazzanti Massimiliano , Tagliapietra Simone
Published: June 2024

The sustainability transition is a macro-scale process that calls for a deep transformation of the economy, society and technological system to achieve a better life in prosperity [...]
Influence of Polyphenols on the Resistance of Traditional and Conventional Apple Varieties to Infection by Penicillium expansum during Cold Storage
Authors: Gotal Skoko Ana-Marija , Skendrović Babojelić Martina , Šarkanj Bojan , Flanjak Ivana , Tomac Ivana , Jozinović Antun , Babić Jurislav , Šubarić Drago , Sulyok Michael , Krska Rudolf , Kovač Tihomir , Lončarić Ante
Published: June 2024

This study investigates the impact of polyphenols on the susceptibility of traditional and conventional apple varieties to Penicillium expansum infection and subsequent patulin biosynthesis during cold storage. Traditional varieties, notably ‘Bobovec’, exhibit significantly higher levels of total polyphenols (650.56 ± 9.85 mg/L) and flavonoids (184.11 ± 1.48 g/kg dw) compared to conventional ones after six months of storage, accompanied by the identification of key polyphenols such as chlorogenic acid, epicatechin, phloridzin, quercetin and procyanidins B1 and B2. These traditional varieties demonstrate enhanced resistance to P. expansum infection, as evidenced by prolonged periods for colony formation, particularly ‘Bobovec’ with an average of 384 h. Furthermore, the traditional variety ‘Winter Banane’ and conventional varieties ‘Idared’ and ‘Fuji’ showed increased patulin biosynthesis postinoculation, indicating higher susceptibility to fungal infection. The findings underscore the potential of polyphenols from traditional apple varieties as natural defences against fungal infections, suggesting the importance of selecting or breeding varieties with higher polyphenol content to improve resistance to postharvest pathogens, thereby enhancing the quality and safety of stored apples.
Research on the Spatial Differences and Network Structure of Economic Development in the Yangtze River Belt, China
Authors: Zhao Ziyang , Cai Yihui
Published: June 2024

The Yangtze River economic belt is the main force leading the high-quality development of China’s economy, but its current internal economic differentiation issues require further study. In this study, to understand the development laws, change characteristics, evolutionary pattern, and main influencing factors on economic differences and economic network structure in the Yangtze River economic belt, 20 years of data from 1999 to 2018 at the general scale, three major regions, province, and city scales were analyzed. The results indicated that from 1999 to 2018, the total GDP of the Yangtze River economic belt steadily increased year by year, and the absolute difference in regional economy showed an expanding trend, while the relative difference was relatively stable. The total economic output and proportion of the three major regions all showed a trend of eastern region > central region > western region, but the growth rate and proportion trends were exactly the opposite. The GDP of 11 provinces and 110 cities showed positive global autocorrelation and obvious local spatial autocorrelation, but their radiative driving effect on surrounding areas was not strong, and the spatial agglomeration effect at the provincial level was better than that at the prefecture level or city level. The economic network structure was characterized by a single center structure dominated by the Shanghai and Jiangsu Province, gradually strengthening from west to east, and the gravity value growth rate in the western region was significantly higher than in the central and eastern regions. The city cluster in the middle reaches of the Yangtze River and the Chengdu–Chongqing served as the main bridges and links, playing a crucial role in the cascade radiation process of economic connections. The research results have strategic significance for coordinating the region development of the Yangtze River economic belt and promoting the rise of central China.
Coupling Coordination Evaluation of Water and Soil Resource Matching and Grain Production, and Analysis of Obstacle Factors in a Typical Black Soil Region of Northeast China
Authors: Chu Hao , Wu Cui , Wang Guixia , Lang Yu , Aynalem Mezgebu
Published: June 2024

The coordinated development of water and soil resource matching and grain production is essential to enhance integrated grain production capacity and promote sustainable development in agriculture. Based on the perspective of a water footprint, this article empirically evaluates the coupling coordination relationship between water and soil resource matching and grain production in typical black soil areas in Northeast China using the coupled coordination degree and the obstacle model and further analyzes the obstacle factors that affect the coordination between the two systems. The results indicate that the blue water footprint, green water footprint, and total water footprint of five grain crops are increasing year by year. Soybean has the largest water footprint per unit mass, tubers have the smallest, and rice has the largest water footprint among cereals. The overall matching degree of water and soil resources in the study area is steadily increasing. However, there are significant differences in the water and soil resource matching coefficients between regions, with the highest being observed in Hegang City and the lowest being observed in Jiamusi City. Coupling remains at a high level and coupling coordination shifts from a low–middle–high to a middle–high stage. The correlation between soil and water resource matching and grain production systems is of significant importance. The degree of matching between water and soil resources serves as the primary obstacle affecting the coupling and coordinated development of integrated systems, which fundamentally restricts the sustainable development of regional agriculture.
Analysis of Deforestation and Water Quality in the Talgua River Watershed (Honduras): Ecosystem Approach Based on the DPSIR Model
Authors: Saravia-Maldonado Selvin Antonio , Fernández-Pozo Luis Francisco , Ramírez-Rosario Beatriz , Rodríguez-González María Ángeles
Published: June 2024

With increasing urbanization and industrialization, soil and forest resources are facing considerable pressure, as well as the demand for water for domestic, agricultural, and industrial activities. Therefore, it is essential to conduct regular assessments of water quality and ensure that water is consistently maintained in the context of ecosystem services (ESs). Our objective was to apply the driving forces–pressures–state–impacts–responses (DPSIR) model to understand the cause–effect relationships and interactions with anthropogenic pressures on deforestation and water quality in the Talgua River watershed and associated valley and plain areas in central-eastern Honduras. Physicochemical and microbiological analyses were conducted to determine the water quality index (NSF–WQI) and other contamination indexes. The results identified high contamination by coliforms, up to 920.00 NPM/100 mL, and high levels of contamination by organic matter (ICOMO, 0.65), solids (ICOSUS, 0.79), mineralization (ICOMI, 0.99), and the presence of bacteria (BPI, 8.50), as well as the development of eutrophication processes (ICOTRO), resulting in generally low water quality. These problems were caused by the socio-demographic and economic growth of the area, as well as the high demand for water, vulnerability to climate change, and intense agro-livestock and industrial activity, which led to deforestation processes, changes in land use, and contamination of natural water bodies that impacted the overexploitation of aquifers. After applying the DPSIR model, strategies are proposed for the management and administration of the watershed aimed at preserving the water, soils, and forest resources, while promoting stakeholder, business, education sector, and public administration participation.
Design and Experimental Results of an AIoT-Enabled, Energy-Efficient Ceiling Fan System
Authors: Khan Hashim Raza , Ahmed Wajahat , Masud Wasiq , Alam Urooj , Arshad Kamran , Assaleh Khaled , Qazi Saad Ahmed
Published: June 2024

With technological advancements, domestic appliances are leveraging smart technologies for getting smarter through learning from their past usage to enhance user comfort and energy efficiency. Among these, ceiling fans, though widely used in Lower- and Middle-Income Countries (LMICs) in temperate regions, still lack a cohesive system integrating all necessary sensors with a machine learning-based system to optimize their operation for comfort and energy saving and to experimentally verify the performance under different usage scenarios that could transform a high-power-consuming device into an energy-efficient system. Therefore, the present research proposes an experimentally verified and energy-efficient Artificial Intelligence of Things (AIoT)-based system that could be retrofitted with regular DC ceiling fans. An Internet of Things (IoTs) circuit, equipped with an ESP8266 microcontroller, temperature, humidity, and motion sensors, was designed to communicate with a developed Android application and an online dashboard. A total of 123 ceiling fans with the designed IoTs circuit were deployed at various household locations for two years, with manual operations for the first year. In the next year, an auto mode based on the predictions of the machine learning model was introduced. The experimental outcomes showed that the fan with added smart features reduced the energy loss by almost 50% as compared to conventional AC ceiling fans. Consequently, the carbon footprint of the appliances is reduced significantly. A high user-rated acceptability of the system, examined through a standard measure, was also achieved.