The 2023 MDPI Annual Report has
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28 pages, 971 KiB  
Article
Integrated Decision-Making of Urban Agriculture within the Greyfield Regeneration Environments (UAGR)
by Wenli Dong and Gangjian Lin
Buildings 2024, 14(5), 1415; https://doi.org/10.3390/buildings14051415 (registering DOI) - 14 May 2024
Abstract
Various urban environmental and social challenges have emerged during the rapid urban development. Urban agriculture has emerged as one of the practical solutions to address these urban issues and climate change. This study aims to establish a decision model for urban agriculture regeneration [...] Read more.
Various urban environmental and social challenges have emerged during the rapid urban development. Urban agriculture has emerged as one of the practical solutions to address these urban issues and climate change. This study aims to establish a decision model for urban agriculture regeneration that can be applied to improve the implementation of related projects. The study first reviews existing research on Urban Agriculture within the Greyfield Regeneration Environments (UAGR) and outlines the processes involved, including project initiation, construction, and operation management. It identifies 25 factors influencing UAGR and employs the Fuzzy Delphi method (FDM) to prioritize them based on expert judgments. Subsequently, the interpretative structural model (ISM) analysis method is applied to analyze the interrelationships among the 11 most important factors. Matrix operations and MATLAB programming are utilized to establish the influence relationship model based on expert questionnaires to determine the influence between each pair of factors. This results in a hierarchically structured decision model for UAGR. Finally, the decision-making model is applied to analyze the case study in Shanghai and Hangzhou. As urban agricultural activities are proliferating in rapid urbanization, the establishment of a decision-making model for UAGR can offer practical guidance to practitioners, facilitating the development of urban agriculture and mitigating climate change. Full article
(This article belongs to the Section Architectural Design, Urban Science, and Real Estate)
17 pages, 4655 KiB  
Article
Design of Mixed-Mode Analog PID Controller with CFOAs
by Natchanai Roongmuanpha, Jetsdaporn Satansup, Tattaya Pukkalanun and Worapong Tangsrirat
Sensors 2024, 24(10), 3125; https://doi.org/10.3390/s24103125 (registering DOI) - 14 May 2024
Abstract
The design of a mixed-mode proportional-integral-derivative (PID) controller circuit using current-feedback operational amplifiers (CFOAs) as active components is proposed. With the same circuit topology, the proposed configuration of three CFOAs, four resistors, and two capacitors is capable of performing the PID controller in [...] Read more.
The design of a mixed-mode proportional-integral-derivative (PID) controller circuit using current-feedback operational amplifiers (CFOAs) as active components is proposed. With the same circuit topology, the proposed configuration of three CFOAs, four resistors, and two capacitors is capable of performing the PID controller in each of the following four modes: voltage mode, trans-admittance mode, current mode, and trans-impedance mode. Numerous mathematical analyses are conducted to determine the controller’s performance under both ideal and non-ideal conditions. Additionally, the mixed-mode second-order lowpass filter is suggested and also used to examine the workability of the proposed mixed-mode PID controller in a feedback control structure. The proposed PID controller is implemented with the commercially available IC-type CFOA AD844, and the simulation results are presented to illustrate the functionality of the controller and its closed-loop control system. According to the findings, the total power consumption of the proposed PID controller is 0.348 W, with symmetrical supply voltages of ±9 V. It also has a temperature variation of less than 0.2% over the AD844’s usable range. Monte Carlo statistical analysis results revealed that the gain responses of the controller exhibited a deviation of no more than 7.72% from the theoretical value. The controlled filter in a closed-loop control system has a 43% faster rise time and peak time than the uncontrolled filter in all four modes of operation. It also has a steady-state error less than 0.2 mV for voltage responses and 0.72 µA for current responses. Full article
(This article belongs to the Section Electronic Sensors)
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19 pages, 7477 KiB  
Article
Effect of Asphaltenes and Asphaltene Dispersants on Wax Precipitation and Treatment
by Oualid M’barki, John Clements and Quoc P. Nguyen
Colloids Interfaces 2024, 8(3), 30; https://doi.org/10.3390/colloids8030030 (registering DOI) - 14 May 2024
Abstract
A detailed understanding of the interactions between wax and asphaltenes with other components of crude oils and the effect of treatments with paraffin inhibitors (PIs) and asphaltene dispersants (ADs), with a focus on identifying specific structure-activity relationships, is necessary to develop effective flow [...] Read more.
A detailed understanding of the interactions between wax and asphaltenes with other components of crude oils and the effect of treatments with paraffin inhibitors (PIs) and asphaltene dispersants (ADs), with a focus on identifying specific structure-activity relationships, is necessary to develop effective flow assurance strategies. The morphological and rheological consequences of treating wax and asphaltenes in oils of differing composition with a series of ADs having structural features in common with an alpha olefin-maleic anhydride (AO-MA) comb-like copolymer PI were assessed alone and in combination with said PI. Of the four ADs studied, two were identified as being effective dispersants of asphaltenes in heptane-induced instability tests and in a West Texas (WT) crude. The degree to which a low concentration of asphaltenes stabilizes wax in the absence of treatment additives is lessened in oils having greater aromatic fractions. This is because these stabilizing interactions are replaced by more energetically favorable aromatic–asphaltene interactions, increasing oil viscosity. Treatment with AD alone also reduces the extent of wax–asphaltene interactions, increasing oil viscosity. In concert with the PI, treatment with the AD having greater structural similarity with the PI appears to improve wax solubility in both the presence and absence of asphaltenes. However, the viscosity of the treated oils is greater than that of the oil treated with PI alone, while treatment with AD having lesser structural similarity with the PI does not adversely affect oil viscosity. These data suggest that rather than treating both wax and asphaltenes, AD may poison the function of the PI. These data illuminate the pitfalls of designing flow assurance additives to interact with both wax and asphaltenes and developing treatment plans. Full article
(This article belongs to the Special Issue Crude Oil Recovery)
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18 pages, 8711 KiB  
Article
Geochemical Characteristics and U–Pb Dating of Granites in the Western Granitoid Belt of Thailand
by Etsuo Uchida, Takumi Yokokura, Sota Niki and Takafumi Hirata
Geosciences 2024, 14(5), 135; https://doi.org/10.3390/geosciences14050135 (registering DOI) - 14 May 2024
Abstract
This paper presents the integration of magnetic susceptibility measurements and whole-rock geochemical compositional and Nd–Sr isotopic ratio analyses for granite samples collected from the Ranong, Lam Pi, Ban Lam Ru, and Phuket granite bodies in the Western Granitoid Belt of Thailand. In addition, [...] Read more.
This paper presents the integration of magnetic susceptibility measurements and whole-rock geochemical compositional and Nd–Sr isotopic ratio analyses for granite samples collected from the Ranong, Lam Pi, Ban Lam Ru, and Phuket granite bodies in the Western Granitoid Belt of Thailand. In addition, U–Pb dating was performed on zircons extracted from the samples. All samples are proper granites based on their mineralogical and geochemical characteristics. Two samples collected from the Lam Pi granite body were classified as magnetite-series and I-type. The remaining granite samples were classified as ilmenite-series and S- or A-type. Furthermore, all granites were classified as syn-collision granites. Excluding the magnetite-series samples from the Lam Pi granite body, the other samples exhibit enrichment in incompatible elements, such as Nb, Sn, Ta, Pb, Bi, Th, U, Ce, Rb, and Cs. Zircon U–Pb dating yielded ages of ca. 60 Ma for the magnetite-series granites from the Lam Pi granite body, whereas ages of 88–84 Ma were obtained for the other granite bodies. Initial Nd–Sr isotopic ratios indicate a higher contribution of mantle material in the Lam Pi magnetite-series granites and a higher contribution of continental crust material in the other granites. Based on these compositional and zircon U–Pb age data, it is inferred that the 88–84 Ma granites formed as a result of the thickening of the continental crust owing to the collision between the Sibumasu and the West Burma blocks. In contrast, the ca. 60 Ma Lam Pi magnetite-series granites are thought to have been generated via partial melting of the mantle wedge associated with the subduction of the Neo-Tethyan oceanic crust beneath the West Burma Block. Full article
(This article belongs to the Section Geochemistry)
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12 pages, 299 KiB  
Article
Assessing Nutritional Status in Gastric Cancer Patients after Total versus Subtotal Gastrectomy: Cross-Sectional Study
by Fawzy Akad, Bogdan Filip, Cristina Preda, Florin Zugun-Eloae, Sorin Nicolae Peiu, Nada Akad, Dragos-Valentin Crauciuc, Ruxandra Vatavu, Liviu-Ciprian Gavril, Roxana-Florentina Sufaru and Veronica Mocanu
Nutrients 2024, 16(10), 1485; https://doi.org/10.3390/nu16101485 (registering DOI) - 14 May 2024
Abstract
Gastric cancer (GC) remains a significant global health concern, ranking as the third leading cause of cancer-related deaths. Malnutrition is common in GC patients and can negatively impact prognosis and quality of life. Understanding nutritional issues and their management is crucial for improving [...] Read more.
Gastric cancer (GC) remains a significant global health concern, ranking as the third leading cause of cancer-related deaths. Malnutrition is common in GC patients and can negatively impact prognosis and quality of life. Understanding nutritional issues and their management is crucial for improving patient outcomes. This cross-sectional study included 51 GC patients who underwent curative surgery, either total or subtotal gastrectomy. Various nutritional assessments were conducted, including anthropometric measurements, laboratory tests, and scoring systems such as Eastern Cooperative Oncology Group/World Health Organization Performance Status (ECOG/WHO PS), Observer-Reported Dysphagia (ORD), Nutritional Risk Screening-2002 (NRS-2002), Patient-Generated Subjective Global Assessment (PG-SGA), and Simplified Nutritional Appetite Questionnaire (SNAQ). Serum carcinoembryonic antigen (CEA) levels were significantly higher in the subtotal gastrectomy group. Nutritional assessments indicated a higher risk of malnutrition in patients who underwent total gastrectomy, as evidenced by higher scores on ORD, NRS-2002, and PG-SGA. While total gastrectomy was associated with a higher risk of malnutrition, no single nutritional parameter emerged as a strong predictor of surgical approach. PG-SGA predominantly identified malnutrition, with its occurrence linked to demographic factors such as female gender and age exceeding 65 years. Full article
10 pages, 481 KiB  
Systematic Review
The Prevalence of Caregiving among Young People
by Lawrence T. Lam and Mary K. Lam
Int. J. Environ. Res. Public Health 2024, 21(5), 621; https://doi.org/10.3390/ijerph21050621 (registering DOI) - 14 May 2024
Abstract
With the increasing number of people with chronic diseases and disabilities, the number of family members as caregivers have also been growing. Despite the attention paid to caregiving in recent years, little is known about caregiving among young people, particularly its global prevalence. [...] Read more.
With the increasing number of people with chronic diseases and disabilities, the number of family members as caregivers have also been growing. Despite the attention paid to caregiving in recent years, little is known about caregiving among young people, particularly its global prevalence. The lack of information has important implications for health policy and management, resulting in the inability to form appropriate evidence-based policies and managerial decision making. This study aims to derive an estimate of the prevalence of caregiving among young people through a systematic review of the current literature. The results of this study revealed a prevalence of caregiving among younger adolescents of between 1.1% (1.06–1.14%) and 12.0% (11.02–12.98%). However, the assessment of caregiving varies across studies, and all were conducted in developed countries. These results provide information on the burden of caregiving in young people and reveal the lack of global information, calling for more research on and attention to this specific population. Full article
14 pages, 1882 KiB  
Article
Friction-Wear and Noise Characteristics of Friction Disks with Circular Texture
by Biao Ma, Weichen Lu, Liang Yu, Cenbo Xiong, Guoqiang Dang and Xiaobo Chen
Materials 2024, 17(10), 2337; https://doi.org/10.3390/ma17102337 (registering DOI) - 14 May 2024
Abstract
The reduction of friction-induced noise is a crucial research area for enhancing vehicle comfort, and this paper proposes a method based on circular pit texture to achieve this goal. We conducted a long-term sliding friction test using a pin-on-disc friction and a wear [...] Read more.
The reduction of friction-induced noise is a crucial research area for enhancing vehicle comfort, and this paper proposes a method based on circular pit texture to achieve this goal. We conducted a long-term sliding friction test using a pin-on-disc friction and a wear test bench to verify the validity of this method. To compare the friction noise of different surfaces, texture units with varying line densities were machined on the surface of friction disk samples. The resulting friction-wear and noise characteristics of the samples were analyzed in conjunction with the microscopic morphology of the worn surfaces. The results indicate that surfaces with textures can delay the onset of squeal noise, and the pattern of its development differs from that of smooth surfaces. The noise reduction effect is most evident due to the proper distribution of textures that can form furrow-like wear marks at the wear interface. The finite element results demonstrate that this morphology can improve pressure distribution at the leading point and reduce the tendency of system instability. Full article
(This article belongs to the Special Issue Evolution of the Working Performance of Special Materials)
22 pages, 3452 KiB  
Article
Corrosion Behavior of Ni-Cr Alloys with Different Cr Contents in NaCl-KCl-MgCl2
by Peng Lei, Lizhen Zhou, Yu Zhang, Fuli Wang, Qinzhe Li, Jiangyan Liu, Xueyun Xiang, Hang Wu, Wen Wang and Fuhui Wang
Materials 2024, 17(10), 2335; https://doi.org/10.3390/ma17102335 (registering DOI) - 14 May 2024
Abstract
This study investigates the corrosion behavior of Ni-Cr binary alloys, including Ni-10Cr, Ni-15Cr, Ni-20Cr, Ni-25Cr, and Ni-30Cr, in a NaCl-KCl-MgCl2 molten salt mixture through gravimetric analysis. Corrosion tests were conducted at 700 °C, with the maximum immersion time reaching up to 100 [...] Read more.
This study investigates the corrosion behavior of Ni-Cr binary alloys, including Ni-10Cr, Ni-15Cr, Ni-20Cr, Ni-25Cr, and Ni-30Cr, in a NaCl-KCl-MgCl2 molten salt mixture through gravimetric analysis. Corrosion tests were conducted at 700 °C, with the maximum immersion time reaching up to 100 h. The corrosion rate was determined by measuring the mass loss of the specimens at various time intervals. Verifying corrosion rates by combining mass loss results with the determination of element dissolution in molten salts using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Detailed examinations of the corrosion products and morphology were conducted using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Micro-area elemental analysis on the corroded surfaces was performed using an energy dispersive spectrometer (EDS), and the elemental distribution across the corrosion cross-sections was mapped. The results indicate that alloys with lower Cr content exhibit superior corrosion resistance in the NaCl-KCl-MgCl2 molten salt under an argon atmosphere compared to those with higher Cr content; no corrosion products were retained on the surfaces of the lower Cr alloys (Ni-10Cr, Ni-15Cr). For the higher Cr alloys (Ni-20Cr, Ni-25Cr, Ni-30Cr), after 20 h of corrosion, a protective layer was observed in certain areas. The formation of a stable Cr2O3 layer in the initial stages of corrosion for high-Cr content alloys, which reacts with MgO in the molten salt to form a stable MgCr2O4 spinel structure, provides additional protection for the alloys. However, over time, even under argon protection, the MgCr2O4 protective layer gradually degrades due to chloride ion infiltration and chemical reactions at high temperatures. Further analysis revealed that chloride ions play a pivotal role in the corrosion process, not only facilitating the destruction of the Cr2O3 layer on the alloy surfaces but also possibly accelerating the corrosion of the metallic matrix through electrochemical reactions. In conclusion, the corrosion behavior of Ni-Cr alloys in the NaCl-KCl-MgCl2 molten salt environment is influenced by a combination of factors, including Cr content, chloride ion activity, and the formation and degradation of protective layers. This study not only provides new insights into the corrosion resistance of Ni-Cr alloys in high-temperature molten salt environments but also offers significant theoretical support for the design and optimization of corrosion-resistant alloy materials. Full article
(This article belongs to the Special Issue Corrosion Mechanism and Protection Technology of Metallic Materials)
23 pages, 5807 KiB  
Article
Experimental Investigation and Design of Novel Hollow Flange Beams under Bending
by Jingya Xue, Shiliang Ma, Xiaomiao Chen, Qing Wu, Yifan Wang, Yunqing Wang, Muhammad Akbar and Ning Yang
Buildings 2024, 14(5), 1413; https://doi.org/10.3390/buildings14051413 (registering DOI) - 14 May 2024
Abstract
In this paper, a new type of assembling rivet-fastened rectangular hollow flange beams (ARHFBs) is proposed. The cross-section of the ARHFB consists of two U-shaped and C-shaped components connected by self-locking rivets to form two rectangular hollow flanges. To study the performance and [...] Read more.
In this paper, a new type of assembling rivet-fastened rectangular hollow flange beams (ARHFBs) is proposed. The cross-section of the ARHFB consists of two U-shaped and C-shaped components connected by self-locking rivets to form two rectangular hollow flanges. To study the performance and strength of the ARHFB as a flexural member, eight four-point bending tests and more than 40 simulation studies were carried out. The details, results, and comparison of the four-point bending tests, especially the characteristics of the test bench and the lateral support, are presented in this paper. ARHFB sections with varied rivet spacing, web depth, and flange width were experimentally studied. Additionally, a parametric study of ARHFB was conducted using finite element models verified by test results. The influence of span on the loading capacity of ARHFB was discussed. ARHFB can be used in large-span buildings. A more economical ARHFB component selection method was given. The depth of the flange, the strength of the web, and the thickness of the web are important parameters of ARHFB. The loading capacity obtained from the test was compared with the predicted values of the design formulas in the American Iron and Steel Institute (AISI) and the Chinese design standard for cold-rolled steel (GB50018). The calculation and verification of ARHFB flange buckling and lateral torsional buckling were also considered. It is recommended that GB50018 be used to predict the flexural capacity of ARHFBs. Full article
(This article belongs to the Section Building Structures)
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16 pages, 683 KiB  
Article
Evaluation of Edible Coatings from Components from Chlorella vulgaris and Comparison with Conventional Coatings
by Alexandra Mari, Charilaos Fafalis and Magdalini Krokida
Coatings 2024, 14(5), 621; https://doi.org/10.3390/coatings14050621 (registering DOI) - 14 May 2024
Abstract
The present customer demand for ready-to-eat food items with higher nutritious value and longer shelf life necessitates creative solutions. An edible coating is a sustainable packaging solution that can prevent food deterioration and preserve food quality. Proteins, starch, and the addition of plasticizers [...] Read more.
The present customer demand for ready-to-eat food items with higher nutritious value and longer shelf life necessitates creative solutions. An edible coating is a sustainable packaging solution that can prevent food deterioration and preserve food quality. Proteins, starch, and the addition of plasticizers are used to create edible coatings. The aim of this study was to develop coating solutions that can best preserve food using isolated starch and proteins from Chlorella vulgaris, and then compare them to coatings that comprise conventional ingredients like chitosan and starch. A number of criteria pertaining to the coatings’ mechanical, optical, thermal, and physical properties were tested. The alternative coatings performed just as well as the conventional ones, with the protein algal coating exhibiting the best thermal, optical, and physical qualities. The food product that needs to be coated can determine which coating is ideal. In conclusion, edible coatings derived from Chlorella vulgaris offer a sustainable solution to preserve ready-to-eat food items, showcasing comparable performance to conventional coatings. Full article
(This article belongs to the Section Coatings for Food Technology and System)
21 pages, 7901 KiB  
Article
Assessing the Feasibility of Removing Graffiti from Railway Vehicles Using Ultra-Freezing Air Projection
by Aina Vega-Bosch, Virginia Santamarina-Campos, Pilar Bosch-Roig, Juan Antonio López-Carrillo, Vicente Dolz-Ruiz and Mercedes Sánchez-Pons
Appl. Sci. 2024, 14(10), 4165; https://doi.org/10.3390/app14104165 (registering DOI) - 14 May 2024
Abstract
Unauthorised graffiti is a challenge in urban environments, affecting railway structures, stations, tracks, and vehicles. Inefficient cleaning methods increase the costs and downtime of railcars, limiting passenger transport. In turn, they are harmful to the operator’s health and the environment, due to the [...] Read more.
Unauthorised graffiti is a challenge in urban environments, affecting railway structures, stations, tracks, and vehicles. Inefficient cleaning methods increase the costs and downtime of railcars, limiting passenger transport. In turn, they are harmful to the operator’s health and the environment, due to the VOCs they release. This study focuses on the feasibility of dry-ice blasting, replacing carbon dioxide with ambient air as an innovative and sustainable solution to remove graffiti from rail vehicles. Experimental tests have been carried out with 13 different aerosols, controlling the temperature (<−80 °C), pressure (up to 3 bar), projection distance (0.5 cm) and exposure times (30″/1′/2′/4′/6′/8′/++). The results showed that ultra-freezing with ambient air preserved the integrity of the support materials and altered the topography, colourimetry and adhesion of the aerosols tested, achieving the total removal of one of the paints. Preliminary results suggest that ultra-freezing with ambient air could be a viable and sustainable solution for graffiti removal on railway structures, transferable to other urban environments. Full article
17 pages, 414 KiB  
Article
Determinants of Weight Status and Body, Health and Life Satisfaction in Young Adults
by Julia Suwalska, Sylwia Łukasik, Maciej Cymerys, Aleksandra Suwalska and Paweł Bogdański
Nutrients 2024, 16(10), 1484; https://doi.org/10.3390/nu16101484 (registering DOI) - 14 May 2024
Abstract
Health behaviors include behavioral patterns and habits that relate to health maintenance, restoration and improvement. They do not only affect the physical condition; they are also associated with life satisfaction. In our study, we focused on young adulthood, a specific lifespan period for [...] Read more.
Health behaviors include behavioral patterns and habits that relate to health maintenance, restoration and improvement. They do not only affect the physical condition; they are also associated with life satisfaction. In our study, we focused on young adulthood, a specific lifespan period for establishing long-term health behavior patterns. The aim of the present study was to investigate depressive symptoms, lifestyle and eating behaviors and delineate their associations with overweight/obesity and body, health and life satisfaction in young adults in Poland. We enrolled 800 students (81.4% females and 18.6% males). Diet, physical activity, depressive symptoms, eating behaviors and body, health and life satisfaction were assessed. Multivariate logistic regression models were employed. Almost half of the participants in our study had at least mild symptoms of depression. Symptoms of depression significantly reduced the odds of satisfaction with body, health and life, whereas physical activity increased them. Overweight/obesity significantly reduced the odds of body and health satisfaction. In women, a history of depression and emotional eating increased the odds of being overweight/obese. The results of our study may contribute to the development of educational programs and intervention strategies for young adults. Full article
(This article belongs to the Special Issue Public Health, Nutritional Behavior and Nutritional Status)
19 pages, 44211 KiB  
Article
Algal Bed Region Segmentation Based on a ViT Adapter Using Aerial Images for Estimating CO2 Absorption Capacity
by Guang Li, Ren Togo, Keisuke Maeda, Akinori Sako, Isao Yamauchi, Tetsuya Hayakawa, Shigeyuki Nakamae, Takahiro Ogawa and Miki Haseyama
Remote Sens. 2024, 16(10), 1742; https://doi.org/10.3390/rs16101742 (registering DOI) - 14 May 2024
Abstract
In this study, we propose a novel method for algal bed region segmentation using aerial images. Accurately determining the carbon dioxide absorption capacity of coastal algae requires measurements of algal bed regions. However, conventional manual measurement methods are resource-intensive and time-consuming, which hinders [...] Read more.
In this study, we propose a novel method for algal bed region segmentation using aerial images. Accurately determining the carbon dioxide absorption capacity of coastal algae requires measurements of algal bed regions. However, conventional manual measurement methods are resource-intensive and time-consuming, which hinders the advancement of the field. To solve these problems, we propose a novel method for automatic algal bed region segmentation using aerial images. In our method, we use an advanced semantic segmentation model, a ViT adapter, and adapt it to aerial images for algal bed region segmentation. Our method demonstrates high accuracy in identifying algal bed regions in an aerial image dataset collected from Hokkaido, Japan. The experimental results for five different ecological regions show that the mean intersection over union (mIoU) and mean F-score of our method in the validation set reach 0.787 and 0.870, the IoU and F-score for the background region are 0.957 and 0.978, and the IoU and F-score for the algal bed region are 0.616 and 0.762, respectively. In particular, the mean recognition area compared with the ground truth area annotated manually is 0.861. Our study contributes to the advancement of blue carbon assessment by introducing a novel semantic segmentation-based method for identifying algal bed regions using aerial images. Full article
13 pages, 8609 KiB  
Article
A Li-Ion Battery State of Charge Estimation Strategy Based on the Suboptimal Multiple Fading Factor Extended Kalman Filter Algorithm
by Weibin Wu, Jinbin Zeng, Qifei Jian, Luxin Tang, Junwei Hou, Chongyang Han, Qian Song and Yuanqiang Luo
Processes 2024, 12(5), 998; https://doi.org/10.3390/pr12050998 (registering DOI) - 14 May 2024
Abstract
The state of charge (SOC) is an important indicator for evaluating a battery management system (BMS), which is crucial for the reliability, performance, and life management of a battery. In this paper, the characteristics of a Li-ion battery are deeply studied to explore [...] Read more.
The state of charge (SOC) is an important indicator for evaluating a battery management system (BMS), which is crucial for the reliability, performance, and life management of a battery. In this paper, the characteristics of a Li-ion battery are deeply studied to explore the charge/discharge curve under different environments. Meanwhile, a second-order RC equivalent circuit model is constructed. The function identification of the EMF and SOC is performed based on the least squares method. The model estimation error is verified by simulation to be less than 0.05 V. Based on the Suboptimal Multiple Fading Factor Extended Kalman Filter (SMFEKF) algorithm, the SOC under constant current and UDDS conditions are estimated. Matlab/simulink simulations illustrate that the estimated accuracy of the proposed algorithm is improved by 79.36% compared with the EKF algorithm. Finally, the validity of the algorithm is verified jointly with the BMS. The results show that the estimation error is within 4% in both constant current condition as well as UDDS conditions, and it can still be predicted quickly and accurately under the uncertainty in the initial value of the SOC. Full article
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11 pages, 268 KiB  
Article
New Oscillation Criteria for Sturm–Liouville Dynamic Equations with Deviating Arguments
by Taher S. Hassan, Clemente Cesarano, Loredana Florentina Iambor, Amir Abdel Menaem, Naveed Iqbal and Akbar Ali
Mathematics 2024, 12(10), 1532; https://doi.org/10.3390/math12101532 (registering DOI) - 14 May 2024
Abstract
The aim of this study is to refine the known Riccati transformation technique to provide new oscillation criteria for solutions to second-order dynamic equations over time. It is important to note that the convergence or divergence of some improper integrals on time scales [...] Read more.
The aim of this study is to refine the known Riccati transformation technique to provide new oscillation criteria for solutions to second-order dynamic equations over time. It is important to note that the convergence or divergence of some improper integrals on time scales depends not only on the integration function but also on the integration time scale. Therefore, there has been a motivation to find new oscillation criteria that can be applicable regardless of whether ζ0Δξa(ξ) is convergent or divergent, in contrast to what has been followed in most previous works in the literature. We have provided an example to illustrate the significance of the obtained results. Full article
25 pages, 19292 KiB  
Article
Expressing the Spatial Concepts of Interior Spaces in Residential Buildings of Huizhou, China: Narrative Methods of Wood-Carving Imagery
by Xuebing Fang, Lili Li, Yi Gao, Niu Liu and Liangsong Cheng
Buildings 2024, 14(5), 1414; https://doi.org/10.3390/buildings14051414 (registering DOI) - 14 May 2024
Abstract
In the interiors of ancient Huizhou buildings in China, a profusion of wood carvings are employed for decoration, with traditional research interpreting their function from decorative and aesthetic perspectives. However, this research suggests that the role of Huizhou wood carvings in interior spaces [...] Read more.
In the interiors of ancient Huizhou buildings in China, a profusion of wood carvings are employed for decoration, with traditional research interpreting their function from decorative and aesthetic perspectives. However, this research suggests that the role of Huizhou wood carvings in interior spaces surpasses mere decoration; they enhance the expression and experience of spatial concepts through narrative imagery. By analyzing the mechanism and intrinsic logic behind the spatial concepts formed in Huizhou residential buildings, this study investigates how wood-carving imagery contributes to shaping spatial concepts through narrative techniques, as well as their creativity and expressiveness in architectural design. Utilizing literature reviews, field surveys for case selection, and case analysis methods combined with observation, interviews, and measurements, this research ultimately employs image analysis to interpret the narrative structures and styles of wood-carving imagery in detail. This study reveals that (1) the spatial concepts of Huizhou residential buildings are influenced by traditional thought, social culture, and other factors, leading to an interweaving of material, cultural, and social spaces that results in a spatial concept characterized by harmony between heaven and humanity, clear hierarchy, and orderliness; (2) Huizhou wood-carvings, through their narrative images, actively engage in the production of spatial concepts, employing thematic juxtaposition narrative modes and utilizing singular-scene narration, composite-scene narration, and cyclical narration to articulate these concepts. These findings significantly deepen our comprehension of the relationship between the spatial concepts of Huizhou’s traditional residential architecture and social culture. By integrating cultural elements with spatial production theory, this research addresses the limitations of existing studies and augments their theoretical interpretative power. Additionally, clarifying the connection between the cultural elements of wood-carving imagery and the formation of spatial concepts offers a novel perspective on the study of Huizhou wood carvings, moving beyond their longstanding categorization as purely decorative elements. Full article
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27 pages, 7596 KiB  
Article
Achievement of a Parameter Window for the Selective Laser Melting Formation of a GH3625 Alloy
by Guozheng Quan, Qi Deng, Yifan Zhao, Mingguo Quan and Daijian Wu
Materials 2024, 17(10), 2333; https://doi.org/10.3390/ma17102333 (registering DOI) - 14 May 2024
Abstract
In the selective laser melting (SLM) process, adjusting process parameters contributes to achieving the desired molten pool morphology, thereby enhancing the mechanical properties and dimensional accuracy of manufactured components. The parameter window characterizing the relationship between molten pool morphology and process parameters serves [...] Read more.
In the selective laser melting (SLM) process, adjusting process parameters contributes to achieving the desired molten pool morphology, thereby enhancing the mechanical properties and dimensional accuracy of manufactured components. The parameter window characterizing the relationship between molten pool morphology and process parameters serves as an effective tool to improve SLM’s forming quality. This work established a mesoscale model of the SLM process for a GH3625 alloy based on the discrete element method (DEM) and computational fluid dynamics (CFD) to simulate the forming process of a single molten track. Subsequently, the formation mechanism and evolution process of the molten pool were revealed. The effects of laser power and scanning speed on the molten pool size and molten track morphology were analyzed. Finally, a parameter window was established from the simulation results. The results indicated that reducing the scanning speed and increasing the laser power would lead to an increase in molten pool depth and width, resulting in the formation of an uneven width in the molten track. Moreover, accelerating the scanning speed and decreasing the laser power cause a reduction in molten pool depth and width, causing narrow and discontinuous molten tracks. The accuracy of the simulation was validated by comparing experimental and simulated molten pool sizes. Full article
(This article belongs to the Special Issue Additive Processing of High-Temperature Alloys)
20 pages, 1080 KiB  
Article
Enhancing Spatial Cognition in Online Virtual Museum Environments: Integrating Game-Based Navigation Strategies for Improved User Experience
by Yuxin Zhang, Boning Zhang, Wansok Jang and Younghwan Pan
Appl. Sci. 2024, 14(10), 4163; https://doi.org/10.3390/app14104163 (registering DOI) - 14 May 2024
Abstract
Online Virtual Museums (OVM) serve as vital conduits for the global propagation of cultural heritage but grapple with the challenge of user disorientation due to the absence of physical references. Leveraging the successful paradigm of game-based virtual navigation, this study investigates the potential [...] Read more.
Online Virtual Museums (OVM) serve as vital conduits for the global propagation of cultural heritage but grapple with the challenge of user disorientation due to the absence of physical references. Leveraging the successful paradigm of game-based virtual navigation, this study investigates the potential integration of game mini-map navigation design elements into OVM to enhance spatial cognition. Through empirical investigation, a conceptual model was developed to probe the role of core mini-map design elements (interactivity, visual guidance, and information content) in augmenting spatial cognition. Results indicate that optimizing these elements significantly enhances user immersion and presence, thereby improving spatial cognition. Specifically, information content and visual guidance exerted stronger effects on immersion and presence, respectively. This research contributes a novel perspective on incorporating game design strategies into non-game virtual experiences, offering practical guidance for enhancing navigation in OVM and similar virtual environments. This bridges the gap between virtual museum navigation and game design, propelling the evolution of more dynamic, interactive, and user-centric virtual environments, thus fostering the preservation and dissemination of digital cultural heritage. Full article
(This article belongs to the Special Issue Advanced Technologies for User-Centered Design and User Experience)
9 pages, 430 KiB  
Editorial
Abiotic Stress Tolerance Boosted by Genetic Diversity in Plants
by Andrés J. Cortés
Int. J. Mol. Sci. 2024, 25(10), 5367; https://doi.org/10.3390/ijms25105367 (registering DOI) - 14 May 2024
Abstract
Plant breeding [1], conservation [2], and restoration [3] efforts necessitate the development of novel adaptive sources to cope with increasing abiotic pressures [4][...] Full article
(This article belongs to the Special Issue Abiotic Stress Tolerance and Genetic Diversity in Plants)
34 pages, 8943 KiB  
Article
Toward Decontamination in Coastal Regions: Groundwater Quality, Fluoride, Nitrate, and Human Health Risk Assessments within Multi-Aquifer Al-Hassa, Saudi Arabia
by Mohamed A. Yassin, Sani I. Abba, Syed Muzzamil Hussain Shah, Abdullahi G. Usman, Johnbosco C. Egbueri, Johnson C. Agbasi, Abid Khogali, Husam Musa Baalousha, Isam H. Aljundi, Saad Sha. Sammen and Miklas Scholz
Water 2024, 16(10), 1401; https://doi.org/10.3390/w16101401 (registering DOI) - 14 May 2024
Abstract
Contamination in coastal regions attributed to fluoride and nitrate cannot be disregarded, given the substantial environmental and public health issues they present worldwide. For effective decontamination, it is pivotal to identify regional pollution hotspots. This comprehensive study was performed to assess the spatial [...] Read more.
Contamination in coastal regions attributed to fluoride and nitrate cannot be disregarded, given the substantial environmental and public health issues they present worldwide. For effective decontamination, it is pivotal to identify regional pollution hotspots. This comprehensive study was performed to assess the spatial as well as indexical water quality, identify contamination sources, hotspots, and evaluate associated health risks pertaining to nitrate and fluoride in the Al-Hassa region, KSA. The physicochemical results revealed a pervasive pollution of the overall groundwater. The dominant water type was Na-Cl, indicating saltwater intrusion and reverse ion exchange impact. Spatiotemporal variations in physicochemical properties suggest diverse hydrochemical mechanisms, with geogenic factors primarily influencing groundwater chemistry. The groundwater pollution index varied between 0.8426 and 4.7172, classifying samples as moderately to very highly polluted. Similarly, the synthetic pollution index (in the range of 0.5021–4.0715) revealed that none of the samples had excellent water quality, with various degrees of pollution categories. Nitrate health quotient (HQ) values indicated chronic human health risks ranging from low to severe, with infants being the most vulnerable. Household use of nitrate-rich groundwater for showering and cleaning did not pose significant health risks. Fluoride HQ decreased with age, and children faced the highest risk of fluorosis. The hazard index (HI) yielded moderate- to high-risk values. Nitrate risks were 1.21 times higher than fluoride risks, as per average HI assessment. All samples fell into the vulnerable category based on the total hazard index (THI), with 88.89% classified as very high risk. This research provides valuable insights into groundwater quality, guiding water authorities, inhabitants, and researchers in identifying safe water sources, vulnerable regions, and human populations. The results highlight the need for appropriate treatment techniques and long-term coastal groundwater management plans. Full article
(This article belongs to the Special Issue Research on Coastal Water Quality Modelling)
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18 pages, 2032 KiB  
Article
Experimental Study of the Implantation Process for Array Electrodes into Highly Transparent Agarose Gel
by Shengjie Wang, Xuan Yan, Xuefeng Jiao and Heng Yang
Materials 2024, 17(10), 2334; https://doi.org/10.3390/ma17102334 (registering DOI) - 14 May 2024
Abstract
Brain–computer interface (BCI) technology is currently a cutting-edge exploratory problem in the field of human–computer interaction. However, in experiments involving the implantation of electrodes into brain tissue, particularly high-speed or array implants, existing technologies find it challenging to observe the damage in real [...] Read more.
Brain–computer interface (BCI) technology is currently a cutting-edge exploratory problem in the field of human–computer interaction. However, in experiments involving the implantation of electrodes into brain tissue, particularly high-speed or array implants, existing technologies find it challenging to observe the damage in real time. Considering the difficulties in obtaining biological brain tissue and the challenges associated with real-time observation of damage during the implantation process, we have prepared a transparent agarose gel that closely mimics the mechanical properties of biological brain tissue for use in electrode implantation experiments. Subsequently, we developed an experimental setup for synchronized observation of the electrode implantation process, utilizing the Digital Gradient Sensing (DGS) method. In the single electrode implantation experiments, with the increase in implantation speed, the implantation load increases progressively, and the tissue damage region around the electrode tip gradually diminishes. In the array electrode implantation experiments, compared to a single electrode, the degree of tissue indentation is more severe due to the coupling effect between adjacent electrodes. As the array spacing increases, the coupling effect gradually diminishes. The experimental results indicate that appropriately increasing the velocity and array spacing of the electrodes can enhance the likelihood of successful implantation. The research findings of this article provide valuable guidance for the damage assessment and selection of implantation parameters during the process of electrode implantation into real brain tissue. Full article
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27 pages, 6698 KiB  
Article
Influence of Subsoil and Building Material Properties on Mine-Induced Soil–Structure Interaction Effect
by Maciej Zajac, Krystyna Kuzniar and Tadeusz Tatara
Appl. Sci. 2024, 14(10), 4164; https://doi.org/10.3390/app14104164 (registering DOI) - 14 May 2024
Abstract
Soil–structure interaction (SSI) refers to the dynamic interaction between a structure and the surrounding soil on which it rests. The behavior of the soil can significantly affect the response of the building structure. In the context of civil engineering and structural analysis, SSI [...] Read more.
Soil–structure interaction (SSI) refers to the dynamic interaction between a structure and the surrounding soil on which it rests. The behavior of the soil can significantly affect the response of the building structure. In the context of civil engineering and structural analysis, SSI becomes particularly important when considering the response of structures to dynamic loads such as earthquakes or so-called paraseismic loads, e.g., mining tremors. Several factors contribute to SSI. Soil and building structure material properties, foundation type, and loading conditions are the most important parameters. The article concerns SSI in the case of mining rock bursts in Poland. The influence of changes in site material conditions and building material properties on the SSI phenomenon was investigated. A few variants of different properties of typical construction materials (brick, reinforced concrete, and cellular concrete) in the case of selected representative building structure were considered. The subsoil material properties from the wide range were also taken into account. Numerical three-dimensional finite element method (FEM) analysis was applied. The adopted models of the soil-structure system were verified by data from in situ experimental vibration measurements. A significant influence of the subgrade material and the building structure material on the SSI was demonstrated. Full article
14 pages, 11264 KiB  
Article
Future Projections of Precipitation Extremes for Greece Based on an Ensemble of High-Resolution Regional Climate Model Simulations
by Prodromos Zanis, Aristeidis K. Georgoulias, Kondylia Velikou, Dimitris Akritidis, Alkiviadis Kalisoras and Dimitris Melas
Atmosphere 2024, 15(5), 601; https://doi.org/10.3390/atmos15050601 (registering DOI) - 14 May 2024
Abstract
An assessment of the projected changes in precipitation extremes for the 21st century is presented here for Greece and its individual administrative regions. The analysis relies on an ensemble of high-resolution Regional Climate Model (RCM) simulations following various Representative Concentration Pathways (RCP2.6, RCP4.5, [...] Read more.
An assessment of the projected changes in precipitation extremes for the 21st century is presented here for Greece and its individual administrative regions. The analysis relies on an ensemble of high-resolution Regional Climate Model (RCM) simulations following various Representative Concentration Pathways (RCP2.6, RCP4.5, and RCP8.5). The simulated changes in future annual total precipitation (PRTOT) under the examined scenarios are generally negative but statistically non-robust, except towards the end of the century (2071–2100) over high-altitude mountainous regions in Western Greece, Peloponnese, and Crete under RCP8.5. The pattern of change in the number of very heavy precipitation days (R20) is linked to the respective pattern of the PRTOT change with a statistically robust decrease of up to −5 days per year only over parts of the high-altitude mountainous regions in Western Greece, Peloponnese, and Crete for 2071–2100 under RCP8.5. Contrasting the future tendency for decrease in total precipitation and R20, the changes in the intensity of precipitation extremes show a tendency for intensification. However, these change patterns are non-robust for all periods and scenarios. Statistical significance is indicated for the highest 1-day precipitation amount in a year (Rx1day) for the administrative regions of Thessaly, Central Greece, Ionian Islands, and North Aegean under RCP8.5 in 2071–2100. The changes in the contribution of the wettest day per year to the annual total precipitation (RxTratio) are mainly positive but non-robust for most of Greece and all scenarios in the period 2021–2050, becoming more positive and robust in 2071–2100 for RCP8.5. This work highlights the necessity of taking into consideration high-resolution multi-model RCM estimates in future precipitation extremes with various scenarios, for assessing their potential impact on flood episodes and the strategic planning of structure resilience at national and regional level under the anticipated human-induced future climate change. Full article
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