The 2023 MDPI Annual Report has
been released!
 
18 pages, 6525 KiB  
Article
Sensor-Based Identification of Singularities in Parallel Manipulators
by Jose L. Pulloquinga, Marco Ceccarelli, Vicente Mata and Angel Valera
Actuators 2024, 13(5), 168; https://doi.org/10.3390/act13050168 (registering DOI) - 01 May 2024
Abstract
Singularities are configurations where the number of degrees of freedom of a robot changes instantaneously. In parallel manipulators, a singularity could reduce the mobility of the end-effector or produce uncontrolled motions of the mobile platform. Thus, a singularity is a critical problem for [...] Read more.
Singularities are configurations where the number of degrees of freedom of a robot changes instantaneously. In parallel manipulators, a singularity could reduce the mobility of the end-effector or produce uncontrolled motions of the mobile platform. Thus, a singularity is a critical problem for mechanical design and model-based control. This paper presents a general sensor-based method to identify singularities in the workspace of parallel manipulators with low computational cost. The proposed experimental method identifies a singularity by measuring sudden changes in the end-effector movements and huge increments in the forces applied by the actuators. This paper uses an inertial measurement unit and a 3D tracking system for measuring the end-effector movements, and current sensors for the forces exerted by the actuators. The proposed sensor-based identification of singularities is adjusted and implemented in three different robots to validate its effectiveness and feasibility for identifying singularities. The case studies are two prototypes for educational purposes—a five-bar mechanism and an L-CaPaMan parallel robot—and a four-degree-of-freedom robot for rehabilitation purposes. The tests showcase its potential as a practical solution for singularity identification in educational and industrial robots. Full article
(This article belongs to the Special Issue Advanced Robots: Design, Control and Application—2nd Edition)
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16 pages, 294 KiB  
Review
A Review of Childhood Developmental Changes in Attention as Indexed in the Electrical Activity of the Brain
by Sirel Karakaş
Brain Sci. 2024, 14(5), 458; https://doi.org/10.3390/brainsci14050458 (registering DOI) - 01 May 2024
Abstract
This review aims to present age-related changes in the neuroelectric responses of typically developing children (TDC) who are presumed to meet developmental stages appropriately. The review is based on findings from the frequently used neuropsychological tasks of active attention, where attention is deliberately [...] Read more.
This review aims to present age-related changes in the neuroelectric responses of typically developing children (TDC) who are presumed to meet developmental stages appropriately. The review is based on findings from the frequently used neuropsychological tasks of active attention, where attention is deliberately focused versus passive attention where attention is drawn to a stimulus, facilitatory attention, which enhances the processing of a stimulus versus inhibitory attention, which suppresses the processing of a stimulus. The review discusses the early and late stages of attentional selectivity that correspond to early and late information processing. Age-related changes in early attentional selectivity were quantitatively represented in latencies of the event-related potential (ERP) components. Age-related changes in late attentional selectivity are also qualitatively represented by structural and functional reorganization of attentional processing and the brain areas involved. The purely bottom-up or top-down processing is challenged with age-related findings on difficult tasks that ensure a high cognitive load. TDC findings on brain oscillatory activity are enriched by findings from attention deficit hyperactivity disorder (ADHD). The transition from the low to fast oscillations in TDC and ADHD confirmed the maturational lag hypothesis. The deviant topographical localization of the oscillations confirmed the maturational deviance model. The gamma-based match and utilization model integrates all levels of attentional processing. According to these findings and theoretical formulations, brain oscillations can potentially display the human brain’s wholistic–integrative functions. Full article
28 pages, 19661 KiB  
Article
Open Ground Story Mid-Rise Buildings Represented by Simplified Systems
by José L. Cabrera, Sonia E. Ruiz and Amador Teran-Gilmore
Buildings 2024, 14(5), 1269; https://doi.org/10.3390/buildings14051269 (registering DOI) - 01 May 2024
Abstract
An improved methodology for the condensation of Multi-Degree-Of-Freedom (MDOF) systems to equivalent Two-Degree-Of-Freedom (2EDOF) systems is presented. The methodology is applied to mid-rise buildings with Open Ground-Story and verified by means of Nonlinear Time History Analyses. The buildings studied are divided into two [...] Read more.
An improved methodology for the condensation of Multi-Degree-Of-Freedom (MDOF) systems to equivalent Two-Degree-Of-Freedom (2EDOF) systems is presented. The methodology is applied to mid-rise buildings with Open Ground-Story and verified by means of Nonlinear Time History Analyses. The buildings studied are divided into two main segments: (a) ground story, whose stiffness and lateral strength are both provided only by reinforced concrete moment-resisting frames; and (b) from the second story to the roof, whose stiffness and lateral strength are provided by confined masonry walls. The proposed methodology allows us to do the following: (a) get the closest approximation to the real behavior of the MDOF system through the use of hysteresis rules with strength and stiffness degradation in the simplified system; (b) analyze the behavior of an OGS whose lateral stiffness is lower than the stiffness of the stories above; and (c) identify in which of the two subsystems (either the ground story with reinforced concrete frames or the second story with masonry) the maximum seismic demand of non-linear behavior occurs. For most of the cases studied and different scenarios of non-linear behavior, the 2EDOF simplified system reasonably approximates the MDOF system’s response; however, when a local failure in an upper story causes the collapse mechanism, the 2EDOF system does not adequately approximate the response of the MDOF system. Full article
(This article belongs to the Special Issue Structural Engineering in Building)
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17 pages, 2815 KiB  
Article
Magnetic Three-Dimensional Graphene: A Superior Adsorbent for Selective and Sensitive Determination of Nitrite in Water Samples by Ion-Pair Based-Surfactant-Assisted Solid-Phase Extraction Combined with Spectrophotometry
by Mina Vasheghani Farahani, Sajad Karami, Hassan Sereshti, Shokouh Mahpishanian, Somayeh Koupaei Malek and Shahabaldin Rezania
ChemEngineering 2024, 8(3), 47; https://doi.org/10.3390/chemengineering8030047 (registering DOI) - 01 May 2024
Abstract
A straightforward, fast and efficient analytical method was developed which utilizes a magnetic composite called three-dimensional graphene (3D-G@Fe3O4) as an adsorbent to recover nitrite ions (NO2) from environmental water samples. The investigation into the synthesized adsorbent [...] Read more.
A straightforward, fast and efficient analytical method was developed which utilizes a magnetic composite called three-dimensional graphene (3D-G@Fe3O4) as an adsorbent to recover nitrite ions (NO2) from environmental water samples. The investigation into the synthesized adsorbent contained an examination of its morphology, chemical composition, structural attributes, and magnetic properties. This comprehensive analysis was conducted using various instrumental techniques, including Fourier transform-infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Raman spectroscopy, X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH), and vibrating sample magnetometry (VSM). The adsorbent surface was activated by adding cetyltrimethylammonium bromide (CTAB) to the sample solution. To improve the selectivity and sensitivity of the method, nitrite ions were reacted with sulfanilic acid and chromotropic acid sequentially. An orange-red azo-dye complex was formed in the presence of nitrite ions with a clear absorbance peak at 514 nm. The effect of the main experimental parameters such as the pH of the sample solution, adsorbent dosage, and CTAB dosage was explored, and the optimization process was performed using a central composite design (CCD). The linear dynamic range (20–100 ng mL−1) was determined under optimal experimental circumstances, yielding a reasonable determination coefficient (R2, 0.9993), a detection limit of 5.12 ng mL−1, an enrichment factor of 167, and precision values of 1.0% intraday and 2.9% inter-day. The methodology successfully identified minute nitrite ions in environmental water samples with relative recoveries that varied between 96.05 and 101.6 ng mL−1. Full article
(This article belongs to the Collection Green and Environmentally Sustainable Chemical Processes)
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16 pages, 4216 KiB  
Article
Development of Cosmetic Formulations Containing Olive Extract and Spirulina sp.: Stability and Clinical Efficacy Studies
by Gabriela Maria D’Angelo Costa and Patricia Maria Berardo Gonçalves Maia Campos
Cosmetics 2024, 11(3), 68; https://doi.org/10.3390/cosmetics11030068 (registering DOI) - 01 May 2024
Abstract
Cosmetic formulations with natural antioxidants can reduce the oxidative stress caused by solar radiation and pollution. In this context, the aim of this study was to develop and evaluate the clinical efficacy of cosmetic formulations containing olive extract (OE) and Spirulina sp. (SP). [...] Read more.
Cosmetic formulations with natural antioxidants can reduce the oxidative stress caused by solar radiation and pollution. In this context, the aim of this study was to develop and evaluate the clinical efficacy of cosmetic formulations containing olive extract (OE) and Spirulina sp. (SP). For this, rheological behavior, texture, and sensory properties were evaluated. In addition, 31 healthy women with an age of 39 to 60 years, with skin phototypes II and III, and the presence of signs of photoaging on the face were recruited and divided in Group 1 (vehicle formulation) and Group 2 (vehicle with active substances) for this clinical efficacy study. Both groups applied sunscreen daily during the day. The formulations showed non-Newtonian pseudoplastic behaviors and good sensory properties. The clinical evaluation using instrumental measurements showed an increase in skin hydration, an improvement of the skin barrier, and morphological characteristics of the epidermis after 12 weeks of application of the formulations. There was a significant increase in the brightness of the stratum corneum, which suggested a film-forming effect. In addition, both groups had an improvement in the dermis echogenicity, due to the use of sunscreens. Finally, the proposed formulation was effective in protecting the skin and reducing skin changes related to photoaging. Full article
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15 pages, 3214 KiB  
Article
Effect of Diethanol-Isopropanolamine and Typical Supplementary Cementitious Materials on the Hydration Mechanism of BOF Slag Cement Pastes
by Hongyu Wang, Xiaowei Gu, Xiaochuan Xu, Jianping Liu, Zhenguo Zhu and Shenyu Wang
Buildings 2024, 14(5), 1268; https://doi.org/10.3390/buildings14051268 (registering DOI) - 01 May 2024
Abstract
This study investigated the effects of lithium slag and iron tailings on the hydration mechanism of Basic Oxygen Furnace (BOF) slag cement paste with the addition of 0.06% diethanol-isopropanolamine (DEIPA). This study examined the fluidity, compressive strength, pore solution pH, and hydration products [...] Read more.
This study investigated the effects of lithium slag and iron tailings on the hydration mechanism of Basic Oxygen Furnace (BOF) slag cement paste with the addition of 0.06% diethanol-isopropanolamine (DEIPA). This study examined the fluidity, compressive strength, pore solution pH, and hydration products of BOF slag-based composite cementitious materials. The results showed that DEIPA facilitated the conversion from ettringite (AFt) to monosulphate (AFm) and improved the early compressive strength of the BOF slag–cement mortar. Incorporating lithium slag into the DEIPA-containing BOF slag–cement system promoted AFt formation, increased calcium-silicate-hydrate production, and enhanced the microstructure. BOF slag, lithium slag, and iron tailings exhibit synergistic effects in cement pastes. BOF slag and lithium slag provided the reactive components SiO2 and Al2O3. In the early hydration stages, the iron tailings primarily served as fillers, accelerating the system’s reactions. Full article
(This article belongs to the Special Issue Study on Mechanical Properties of Civil Engineering Materials)
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20 pages, 5583 KiB  
Article
Synchronization Control with Dynamics Compensation for Three-Axis Parallel Motion Platform
by Zhiwei Zhou, Jian Gao and Lanyu Zhang
Actuators 2024, 13(5), 166; https://doi.org/10.3390/act13050166 (registering DOI) - 01 May 2024
Abstract
The three-axis parallel motion platform (TAPMP) with a common stator has low motion inertia, enabling highly precise and high-speed motion over a large range of strokes. The primary challenge faced by the TAPMP lies in the mutual pulling exerted between the common stator [...] Read more.
The three-axis parallel motion platform (TAPMP) with a common stator has low motion inertia, enabling highly precise and high-speed motion over a large range of strokes. The primary challenge faced by the TAPMP lies in the mutual pulling exerted between the common stator motors during motion. The driving forces generated by the motors are closely associated with their synchronization motion, a connection often overlooked in the design of existing controllers. To address this issue, this paper presents a novel synchronization controller with dynamics compensation (SC–DC) to achieve motion synchronization between the three motors, ultimately enhancing the platform’s tracking accuracy in task space. In this SC–DC method, the synchronization error of the common stator motors is introduced to represent the synchronized motion relationship between adjacent motors, and a dynamic feedforward control is adopted to compensate for the motor’s driving force. The stability of the proposed controller is analyzed using Lyapunov theory, demonstrating the convergence of both the tracking error and synchronization error. Trajectory tracking simulations and experimental studies are conducted on the TAPMP. The results show that, compared to the augmented proportional-derivative controller with dynamic compensation, the proposed controller significantly reduces both the MAE of the tracking error and synchronization error on the q1 motor by 71.88% and 73.02%, respectively, demonstrating its performance advantages in trajectory tracking and synchronization. Full article
(This article belongs to the Section Actuators for Manufacturing Systems)
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18 pages, 7198 KiB  
Article
Study on Dynamics of Overrunning Spring Clutches and Suppression Methods for Their Abnormal Noise
by Jie Zhou, Zhehang Qiu, Huijuan Zhang and Jianming Zhan
Actuators 2024, 13(5), 165; https://doi.org/10.3390/act13050165 (registering DOI) - 01 May 2024
Abstract
Overrunning spring clutches are widely used as essential transmission devices, and the occurrence of abnormal noise can lead to a decline in their performance. This study investigates the dynamic aspects of abnormal noise in engineering applications, including its causes, influencing factors, and suppression [...] Read more.
Overrunning spring clutches are widely used as essential transmission devices, and the occurrence of abnormal noise can lead to a decline in their performance. This study investigates the dynamic aspects of abnormal noise in engineering applications, including its causes, influencing factors, and suppression methods. Audio processing algorithms are employed to analyze the audio associated with abnormal noise, and the Fourier Motion Blur algorithm is applied to process video images of the springs. By combining the motion blur curve with the noise spectrum curve, the source of the abnormal noise is identified as friction-induced vibrations in the spring. Theoretical modeling and calculations are carried out from a dynamic perspective to validate that the phenomenon of abnormal noise in the clutch is a result of self-excited friction vibration caused by the stick–slip phenomenon. Based on theoretical analysis and practical engineering, surface texturing is added to the center shaft of the spring seat, optimizing the system as an overdamped system to suppress self-vibration. Utilizing CFD simulation analysis, the simulation results are used to improve the texturing parameters and further optimize the texturing shape, resulting in an optimal parallelogram surface texture structure. Experimental validation confirms that the improved overrunning spring clutch completely eliminates abnormal noise during overrunning operation. Therefore, this paper contributes to the understanding of the dynamic issues associated with abnormal noise in overrunning spring clutches, confirming that the mechanism for abnormal noise generation is friction-induced self-excitation vibration, and demonstrating that surface texture optimization methods effectively suppress the occurrence of abnormal noise. Full article
(This article belongs to the Special Issue Nonlinear Active Vibration Control)
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29 pages, 7167 KiB  
Article
A Tube-Based Model Predictive Control for Path Tracking of Autonomous Articulated Vehicle
by Taeyeon Lee and Yonghwan Jeong
Actuators 2024, 13(5), 164; https://doi.org/10.3390/act13050164 (registering DOI) - 01 May 2024
Abstract
This paper presents tube-based Model Predictive Control (MPC) for the path and velocity tracking of an autonomous articulated vehicle. The target platform of this study is an autonomous articulated vehicle with a non-steerable axle. Consequently, the articulation angle and wheel torque input are [...] Read more.
This paper presents tube-based Model Predictive Control (MPC) for the path and velocity tracking of an autonomous articulated vehicle. The target platform of this study is an autonomous articulated vehicle with a non-steerable axle. Consequently, the articulation angle and wheel torque input are determined by the tube-based MPC. The proposed MPC aims to achieve two objectives: minimizing path tracking error and enhancing robustness to disturbances. Furthermore, the lateral stability of the autonomous articulated vehicle is considered to reflect its dynamic characteristics. The vehicle model for the MPC is formulated using local linearization to minimize modeling errors. The reference state is determined using a virtual controller based on the linear quadratic regulator to provide the optimal reference for the MPC solver. The proposed algorithm was evaluated through a simulation study with base algorithms under noise injection into the sensor signal. Simulation results demonstrate that the proposed algorithm achieved the smallest path tracking error, compared to the base algorithms. Additionally, the proposed algorithm demonstrated robustness to external noise for multiple signals. Full article
(This article belongs to the Special Issue Integrated Intelligent Vehicle Dynamics and Control)
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16 pages, 4673 KiB  
Article
Human–Robot Cooperation Control Strategy Design Based on Trajectory Deformation Algorithm and Dynamic Movement Primitives for Lower Limb Rehabilitation Robots
by Jie Zhou, Yao Sun, Laibin Luo, Wenxin Zhang and Zhe Wei
Processes 2024, 12(5), 924; https://doi.org/10.3390/pr12050924 (registering DOI) - 01 May 2024
Abstract
Compliant physical interactions, interactive learning, and robust position control are crucial to improving the effectiveness and safety of rehabilitation robots. This paper proposes a human–robot cooperation control strategy (HRCCS) for lower limb rehabilitation robots. The high-level trajectory planner of the HRCCS consists of [...] Read more.
Compliant physical interactions, interactive learning, and robust position control are crucial to improving the effectiveness and safety of rehabilitation robots. This paper proposes a human–robot cooperation control strategy (HRCCS) for lower limb rehabilitation robots. The high-level trajectory planner of the HRCCS consists of a trajectory generator, a trajectory learner, a desired trajectory predictor, and a soft saturation function. The trajectory planner can predict and generate a smooth desired trajectory through physical human–robot interaction (pHRI) in a restricted joint space and can learn the desired trajectory using the locally weighted regression method. Moreover, a triple-step controller was designed to be the low-level position controller of the HRCCS to ensure that each joint tracks the desired trajectory. A nonlinear disturbance observer is used to observe and compensate for total disturbances. The radial basis function neural networks (RBFNN) approximation law and robust term are adopted to compensate for observation errors. The simulation results indicate that the HRCCS is robust and can achieve compliant pHRI and interactive trajectory learning. Therefore, the HRCCS has the potential to be used in rehabilitation robots and other fields involving pHRI. Full article
(This article belongs to the Section Automation Control Systems)
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17 pages, 1399 KiB  
Article
The Promises and Challenges toward Mass Customization of Healthcare Services
by Shuang Ma, Xiaojin Zhang and Songlin Chen
Systems 2024, 12(5), 156; https://doi.org/10.3390/systems12050156 (registering DOI) - 01 May 2024
Abstract
The healthcare industry is confronted with the challenge to offer an increasing variety of healthcare services while in the meantime controlling rapidly increasing healthcare costs. Mass customization has been proven to be an effective strategy to fulfill customers’ individual specific needs with high [...] Read more.
The healthcare industry is confronted with the challenge to offer an increasing variety of healthcare services while in the meantime controlling rapidly increasing healthcare costs. Mass customization has been proven to be an effective strategy to fulfill customers’ individual specific needs with high efficiency and low cost in the manufacturing industry. This paper investigates the theoretical feasibility and practical applicability of adopting mass customization as a conceptual framework for designing a healthcare service delivery system. The nature of healthcare delivery systems and their evolution are discussed relative to those of manufacturing systems. Recent research in personalized medicine, consumer-driven healthcare, consumer healthcare informatics, and integrated healthcare delivery is reviewed as enabling technologies towards mass customization of healthcare services. By synthesizing these scattered efforts in different streams of literature, this paper concludes that mass customization can contribute to the redesign of healthcare service systems, and delineates a roadmap for future research. Full article
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21 pages, 4274 KiB  
Article
Deep-Learning-Based Strong Ground Motion Signal Prediction in Real Time
by Mohammad AlHamaydeh, Sara Tellab and Usman Tariq
Buildings 2024, 14(5), 1267; https://doi.org/10.3390/buildings14051267 (registering DOI) - 01 May 2024
Abstract
Processing ground motion signals at early stages can be advantageous for issuing public warnings, deploying first-responder teams, and other time-sensitive measures. Multiple Deep Learning (DL) models are presented herein, which can predict triaxial ground motion accelerations upon processing the first-arriving 0.5 s of [...] Read more.
Processing ground motion signals at early stages can be advantageous for issuing public warnings, deploying first-responder teams, and other time-sensitive measures. Multiple Deep Learning (DL) models are presented herein, which can predict triaxial ground motion accelerations upon processing the first-arriving 0.5 s of recorded acceleration measurements. Principal Component Analysis (PCA) and the K-means clustering algorithm were utilized to cluster 17,602 accelerograms into 3 clusters using their metadata. The accelerograms were divided into 1 million input–output pairs for training, 100,000 for validation, and 420,000 for testing. Several non-overlapping forecast horizons were explored (1, 10, 50, 100, and 200 points). Various architectures of Artificial Neural Networks (ANNs) were trained and tested, such as Convolutional Neural Networks (CNN), Recurrent Neural Networks (RNN), Long Short-Term Memory (LSTM) networks, and CNN-LSTMs. The utilized training methodology applied different aspects of supervised and unsupervised learning. The LSTM model demonstrated superior performance in terms of short-term prediction. A prediction horizon of 10 timesteps in the future with a Root Mean Squared Error (RMSE) value of 8.43 × 10−6 g was achieved. In other words, the LSTM model exhibited a performance improvement of 95% compared to the baseline benchmark, i.e., ANN. It is worth noting that all the considered models exhibited acceptable real-time performance (0.01 s) when running in testing mode. The CNN model demonstrated the fastest computational performance among all models. It predicts ground accelerations under 0.5 ms on an Intel Core i9-10900X CPU (10 cores). The models allow for the implementation of real-time structural control responses via intelligent seismic protection systems (e.g., magneto-rheological (MR) dampers). Full article
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21 pages, 5251 KiB  
Article
Cross-Scene Hyperspectral Image Classification Based on Graph Alignment and Distribution Alignment
by Haisong Chen, Shanshan Ding and Aili Wang
Electronics 2024, 13(9), 1731; https://doi.org/10.3390/electronics13091731 (registering DOI) - 01 May 2024
Abstract
A domain alignment-based hyperspectral image (HSI) classification method was designed to address the heterogeneity in resolution and band between the source domain and target domain datasets of cross-scene hyperspectral images, as well as the resulting reduction in common features. Firstly, after preliminary feature [...] Read more.
A domain alignment-based hyperspectral image (HSI) classification method was designed to address the heterogeneity in resolution and band between the source domain and target domain datasets of cross-scene hyperspectral images, as well as the resulting reduction in common features. Firstly, after preliminary feature extraction, perform two domain alignment operations: image alignment and distribution alignment. Image alignment aims to align hyperspectral images of different bands or time points, ensuring that they are within the same spatial reference framework. Distribution alignment adjusts the distribution of features of samples of different categories in the feature space to reduce the distribution differences of the same type of features between two domains. Secondly, adjust the consistency of the two alignment methods to ensure that the features obtained through different alignment methods exhibit consistency in the feature space, thereby improving the comparability and reliability of the features. In addition, this method considers multiple losses in the model from different perspectives and makes comprehensive adjustments through a unified optimization process to more comprehensively capture and utilize the correlation information between data. Experimental results on Houston 2013 and Houston 2018 datasets can improve the hyperspectral prediction performance between datasets with different resolutions and bands, effectively solving the problems of high cost and limited training samples in HSI labeling and significantly improving cross-scene HSI classification performance. Full article
(This article belongs to the Special Issue Recent Trends in Image Processing and Pattern Recognition)
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20 pages, 11156 KiB  
Article
Enhancing the Conductivity and Dielectric Characteristics of Bismuth Oxyiodide via Activated Carbon Doping
by Mohamed Khairy, Faisal K. Algethami, Abdullah N. Alotaibi, Rasmiah S. Almufarij and Babiker Y. Abdulkhair
Molecules 2024, 29(9), 2082; https://doi.org/10.3390/molecules29092082 (registering DOI) - 01 May 2024
Abstract
Activated carbon/BiOI nanocomposites were successfully synthesized through a simplistic method. The produced composites were then characterized using XRD, TEM, SEM-EDX, and XPS. The results showed that BiOI with a tetragonal crystal structure had been formed. The interaction between activated carbon and BiOI was [...] Read more.
Activated carbon/BiOI nanocomposites were successfully synthesized through a simplistic method. The produced composites were then characterized using XRD, TEM, SEM-EDX, and XPS. The results showed that BiOI with a tetragonal crystal structure had been formed. The interaction between activated carbon and BiOI was confirmed via all the mentioned tools. The obtained nanocomposites’ electrical conductivity, dielectric properties, and Ac impedance were studied at 59 KHz−1.29 MHz. AC and dc conductivities were studied at temperatures between 303 and 573 K within the frequency range of 59 KHz–1.29 MHz. The 10% activated carbon/BiOI nanocomposite possessed dc and AC conductivity values of 5.56 × 10−4 and 2.86 × 10−4 Ω−1.cm−1, respectively, which were higher than BiOI and the other nanocomposites. Every sample exhibited increased electrical conductivity values as the temperature and frequency rose, suggesting that all samples had semiconducting behavior. The loss and dielectric constants (ε′ and ε″) also dropped as the frequency increased, leading to higher dielectric loss. The Nyquist plot unraveled single semicircle arcs and a decreased bulk resistance, indicating decreased grain boundary resistance. Consequently, the electrical characteristics of BiOI, 1C/BiOI, 5C/BiOI, and 10C/BiOI implied their applicability as dielectric absorbers, charge-stored capacitors, and high-frequency microwave devices. Full article
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18 pages, 919 KiB  
Article
Intermediate Care for Patient-Centered Care, Shared Decision Making, and Hospital Discharge Support in a Japanese Acute Care Hospital: A Cross-Sectional Study
by Yuko Goto and Hisayuki Miura
Hospitals 2024, 1(1), 32-49; https://doi.org/10.3390/hospitals1010004 (registering DOI) - 01 May 2024
Abstract
[Background] Intermediate care is a limited-time service founded on patient-centered care (PCC) that ensures continuity and quality of care during the transition between home and acute care services, promotes recovery, and restores independence and confidence. In Japan, systematic education on intermediate care for [...] Read more.
[Background] Intermediate care is a limited-time service founded on patient-centered care (PCC) that ensures continuity and quality of care during the transition between home and acute care services, promotes recovery, and restores independence and confidence. In Japan, systematic education on intermediate care for care providers is lacking. [Method] The present study explored the relationship between a Japanese scale used to evaluate individualized discharge support skills, a Japanese version of a tool for evaluating intermediate care based on PCC, and a tool that measures the shared decision making of care providers, which is the pinnacle of PCC. [Results] Clear correlations were found between the concepts evaluated using these three tools. Some concepts were not correlated between the Japanese scale that evaluated individualized discharge support skills and intermediate care based on PCC. [Conclusions] Elucidating the perspectives that help expand discharge care to intermediate care based on PCC will contribute to future education on intermediate care for Japanese care providers and to enriching patient-centered intermediate care. Full article
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20 pages, 3266 KiB  
Article
A Framework for Upscaling of Emerging Chemical Processes Based on Thermodynamic Process Modeling and Simulation
by Hafiz Farooq Imtiaz
ChemEngineering 2024, 8(3), 46; https://doi.org/10.3390/chemengineering8030046 (registering DOI) - 01 May 2024
Abstract
Prospective environmental and technological assessment of emerging chemical processes is necessary to identify, analyze and evaluate the technologies that are highly imperative in the transition towards climate neutrality. The investigation of the environmental impacts and material and energy requirements of the processes at [...] Read more.
Prospective environmental and technological assessment of emerging chemical processes is necessary to identify, analyze and evaluate the technologies that are highly imperative in the transition towards climate neutrality. The investigation of the environmental impacts and material and energy requirements of the processes at the low technology readiness level (TRL) is important in making early decisions about the feasibility of adapting and upscaling the process to the industrial level. However, the upscaling of new chemical processes has always been a major challenge; and in this context, there is no general methodological guidance available in the literature. Hence, a new comprehensive methodological framework for upscaling of novel chemical processes is designed and presented based on thermodynamic process modeling and simulation. The practical implementation of the proposed methodology is extensively discussed by developing a scaled-up novel carbon capture and utilization (CCU) process comprised of sequestration of carbon dioxide (CO2) from blast furnace gas with a capacity of 1000 liter per hour (L/h) using methanol and its utilization as a precursor to produce methane (CH4). It was found that thermodynamic process modeling and simulations based on the perturbed-chain statistical associating (PC-SAFT) equation of state (EOS) can precisely estimate the CO2 solubility in methanol and conversion to CH4 at various temperature and pressure conditions. The achieved thermophysical property and kinetics parameters can be employed in process simulations to estimate scaled-up environmental flows and material and energy requirements of the process. Full article
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17 pages, 4478 KiB  
Article
Research on Damping Hole Optimization of Hydro-Pneumatic Suspension for Mining Trucks under Variable Load Conditions
by Wenfeng Zhu, Zenglu Zhao, Xingtong Zhou, Xuepeng Cao, Min Ye, Chuqing Cao and Mohammad Manjur Alam
Actuators 2024, 13(5), 163; https://doi.org/10.3390/act13050163 (registering DOI) - 01 May 2024
Abstract
The hydro-pneumatic suspension, known for enhancing vehicle ride comfort and stability, finds widespread use in engineering vehicles. Presently, the majority of mining trucks employ hydro-pneumatic suspension with a fixed damping hole, underscoring the critical importance of selecting appropriate damping hole parameters. Initially, an [...] Read more.
The hydro-pneumatic suspension, known for enhancing vehicle ride comfort and stability, finds widespread use in engineering vehicles. Presently, the majority of mining trucks employ hydro-pneumatic suspension with a fixed damping hole, underscoring the critical importance of selecting appropriate damping hole parameters. Initially, an equilibrium mathematical model of the ¼ hydro-pneumatic suspension is established, and the influencing factors of the damping characteristics are analyzed. Subsequently, the simulation model and experimental bench for the hydro-pneumatic suspension are constructed. Sinusoidal signals with different frequencies and amplitudes serve as the excitation signals to analyze the variation trend of the force on the rod with displacement changes. The simulation and experimental results demonstrate a high degree of consistency, validating the rationality and validity of the simulation model. Building upon this foundation, various damping apertures are then selected to study the damping characteristics of the hydro-pneumatic suspension. The research indicates that as the damping aperture increases, the setting time of the hydro-pneumatic suspension system after excitation extends, accompanied by a decrease in the acceleration overshoot. As a result, a comprehensive evaluation index is developed, considering various factors, such as different weight setting times and peak longitudinal accelerations to assess the ride comfort of the suspension. This approach is then employed to determine the optimal damping aperture under both full-load and no-load conditions. The findings of this research offer valuable insights for the development of adaptive variable damping hydraulic suspensions, especially under variable load conditions. Full article
(This article belongs to the Section Actuators for Land Transport)
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16 pages, 1073 KiB  
Article
Effect of Miscellaneous Meals Replacing Soybean Meal in Feed on Growth Performance, Serum Biochemical Parameters, and Microbiota Composition of 25–50 kg Growing Pigs
by Xianliang Zhan, Lei Hou, Zhentao He, Shuting Cao, Xiaolu Wen, Shuai Liu, Yaojie Li, Shaozhen Chen, Huayu Zheng, Dongyan Deng, Kaiguo Gao, Xuefen Yang, Zongyong Jiang and Li Wang
Animals 2024, 14(9), 1354; https://doi.org/10.3390/ani14091354 (registering DOI) - 30 Apr 2024
Abstract
The present study aims to determine the effect of miscellaneous meals (rapeseed meal, cottonseed meal, and sunflower meal) replacing soybean meal in feed on growth performance, apparent digestibility of nutrients, serum biochemical parameters, serum free amino acid content, microbiota composition and SCFAs content [...] Read more.
The present study aims to determine the effect of miscellaneous meals (rapeseed meal, cottonseed meal, and sunflower meal) replacing soybean meal in feed on growth performance, apparent digestibility of nutrients, serum biochemical parameters, serum free amino acid content, microbiota composition and SCFAs content in growing pigs (25–50 kg). A total of 72 (Duroc × Landrace × Yorkshire) growing pigs with initial weights of 25.79 ± 0.23 kg were randomly divided into three treatments. The pigs were fed corn–soybean meal (CON), corn–soybean–miscellaneous meals (CSM), and corn–miscellaneous meals (CMM). Each treatment included six replicates with four pigs per pen (n = 24, 12 barrows and 12 gilts). Soybean meal accounted for 22.10% of the basal diet in the CON group. In the CSM group, miscellaneous meals partially replaced soybean meal with a mixture of 4.50% rapeseed meal, 3.98% cottonseed meal, and 4.50% sunflower meal. In the CMM group, miscellaneous meals entirely replaced soybean meal with a mixture of 8.50% rapeseed meal, 8.62% cottonseed meal, and 8.5% sunflower. The results showed that compared with the CON, the CSM and CMM groups significantly improved the average daily gain (ADG) of growing pigs during the 25–50 kg stage (p < 0.05) but had no effects on average daily feed intake (ADFI) and average daily feed intake/average daily gain (F/G) (p > 0.05). Moreover, the CMM group significantly reduced nutrient apparent digestibility of gross energy compared with the CON group. The serum biochemical parameters results showed that the CSM group significantly improved the contents of total protein (TP) compared with the CON group (p < 0.05). The CMM group significantly improved the contents of total protein (TP), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) compared with the CON group in serum (p < 0.05). In comparison with the CON group, the CMM group also significantly improved lysine (Lys), threonine (Thr), valine (Val), isoleucine (Ile), leucine (Leu), phenylalanine (Phe), arginine (Arg), and citrulline (Cit) levels in serum (p < 0.05). However, the CMM group significantly decreased non-essential amino acid content glycine (Gly) in serum compared with CON (p < 0.05), while compared with the CON group, the CSM and CMM groups had no significant effects on the relative abundance, the alpha-diversity, or the beta-diversity of fecal microbiota. Moreover, compared with the CON group, the CSM group significantly increased butyric acid and valeric acid contents of short-chain fatty acids (SCFAs) in feces (p < 0.05). In contrast to the CON group, the CMM group significantly reduced the contents of SCFAs in feces, including acetic acid, propionic acid, and isobutyric acid (p < 0.05). Collectively, the results of the present study indicate that miscellaneous meals (rapeseed meal, cottonseed meal, and sunflower meal) can partially replace the soybean meal and significantly improve the growth performance of growing pigs during the 25–50 kg stage. Thus, miscellaneous meals are a suitable protein source as basal diets to replace soybean meals for 25–50 kg growing pigs. These results can be helpful to further develop miscellaneous meals as a functional alternative feed ingredient to soybean meal. Full article
(This article belongs to the Special Issue Exploration of Sustainable Feed Resources and Pig Dietary Strategies)
21 pages, 24631 KiB  
Article
The Effect of Ultrafine-Grained (UFG) Structure Formed by Equal-Channel Angular Pressing in AA7075 on Wear and Friction in Sliding against Steel and Ceramic Counterbodies
by Andrey V. Filippov, Sergei Y. Tarasov and Ekaterina O. Filippova
Metals 2024, 14(5), 527; https://doi.org/10.3390/met14050527 (registering DOI) - 30 Apr 2024
Abstract
The mechanical characteristics and sliding friction behaviors of AA7075 samples were studied in regard to structural states formed in them by ECAP and depending on the ECAP pass number. In addition, the effect of a counterbody’s material on the tribological characteristics of the [...] Read more.
The mechanical characteristics and sliding friction behaviors of AA7075 samples were studied in regard to structural states formed in them by ECAP and depending on the ECAP pass number. In addition, the effect of a counterbody’s material on the tribological characteristics of the samples was investigated by the examples of AISI 52100 steel, alumina Al2O3 and silicon nitride Si3N4. Vibration acceleration and acoustic emission signals with parameters such as acoustic emission energy and median frequency were used for characterizing the sliding regimes. The structural state and mechanical properties of the ECAPed AA7075 samples significantly affected their wear behaviors in dry sliding. The counterbody material had a significant influence on the formation of a transfer layer and the subsurface deformation of samples. The dynamic behavior of the tribosystem was studied and the relationship between the sliding parameters, vibrometry and acoustic emission signals was established. Full article
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12 pages, 369 KiB  
Article
Montelukast Influence on Lung in Experimental Diabetes
by Cristina Gales, Bogdan Stoica, Gabriela Rusu-Zota and Mihai Nechifor
Medicina 2024, 60(5), 749; https://doi.org/10.3390/medicina60050749 (registering DOI) - 30 Apr 2024
Abstract
Background and Objectives: The influence of montelukast (MK), an antagonist of cysLT1 leukotriene receptors, on lung lesions caused by experimental diabetes was studied. Materials and Methods: The study was conducted on four groups of six adult male Wistar rats. Diabetes was produced by [...] Read more.
Background and Objectives: The influence of montelukast (MK), an antagonist of cysLT1 leukotriene receptors, on lung lesions caused by experimental diabetes was studied. Materials and Methods: The study was conducted on four groups of six adult male Wistar rats. Diabetes was produced by administration of streptozotocin 65 mg/kg ip. in a single dose. Before the administration of streptozotocin, after 72 h, and after 8 weeks, the serum values of glucose, SOD, MDA, and total antioxidant capacity (TAS) were determined. After 8 weeks, the animals were anesthetized and sacrificed, and the lungs were harvested and examined by optical microscopy. Pulmonary fibrosis, the extent of lung lesions, and the lung wet-weight/dry-weight ratio were evaluated. Results: The obtained results showed that MK significantly reduced pulmonary fibrosis (3.34 ± 0.41 in the STZ group vs. 1.73 ± 0.24 in the STZ+MK group p < 0.01) and lung lesion scores and also decreased the lung wet-weight/dry-weight (W/D) ratio. SOD and TAS values increased significantly when MK was administered to animals with diabetes (77.2 ± 11 U/mL in the STZ group vs. 95.7 ± 13.3 U/mL in the STZ+MK group, p < 0.05, and 25.52 ± 2.09 Trolox units in the STZ group vs. 33.29 ± 1.64 Trolox units in the STZ+MK group, respectively, p < 0.01), and MDA values decreased. MK administered alone did not significantly alter any of these parameters in normal animals. Conclusions: The obtained data showed that by blocking the action of peptide leukotrienes on cysLT1 receptors, montelukast significantly reduced the lung lesions caused by diabetes. The involvement of these leukotrienes in the pathogenesis of fibrosis and other lung diabetic lesions was also demonstrated. Full article
(This article belongs to the Section Pharmacology)
22 pages, 6265 KiB  
Article
Hydrologic Sensitivity of a Critical Turkish Watershed to Inform Water Resource Management in an Altered Climate
by Furkan Yunus Emre Cevahir, Jennifer C. Adam, Mingliang Liu and Justin Sheffield
Hydrology 2024, 11(5), 64; https://doi.org/10.3390/hydrology11050064 (registering DOI) - 30 Apr 2024
Abstract
This study introduces a novel sensitivity analysis approach to assess the resilience and susceptibility of hydrologic systems to the stresses of climate change, moving away from conventional top-down methodologies. By exploring the hydrological sensitivity of the upper Kızılırmak River basin using the Variable [...] Read more.
This study introduces a novel sensitivity analysis approach to assess the resilience and susceptibility of hydrologic systems to the stresses of climate change, moving away from conventional top-down methodologies. By exploring the hydrological sensitivity of the upper Kızılırmak River basin using the Variable Infiltration Capacity (VIC) hydrologic model, we employed a sensitivity-based approach as an alternative to the traditional Global Climate Model (GCM)-based methods, providing more insightful information for water managers. Considering the consistent projections of increasing temperature over this region in GCMs, the hydrologic system was perturbed to examine gradients of a more challenging climate characterized by warming and drying conditions. The sensitivity of streamflow, snow water equivalent, and evapotranspiration to temperature (T) and precipitation (P) variations under each perturbation or “reference” climate was quantified. Results indicate that streamflow responds to T negatively under all warming scenarios. As the reference climates become drier, streamflow sensitivity to P increases, indicating that meteorological drought impacts on water availability could be exacerbated. These results suggest that there will be heightened difficulty in managing water resources in the region if it undergoes both warming and drying due to the following setbacks: (1) water availability will shift away from the summer season of peak water demand due to the warming effects on the snowpack, (2) annual water availability will likely decrease due to a combination of warming and lower precipitation, and (3) streamflow sensitivity to hydroclimatic variability will increase, meaning that there will be more extreme impacts to water availability. Water managers will need to plan for a larger set of extreme conditions. Full article
(This article belongs to the Special Issue Runoff Modelling under Climate Change)
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21 pages, 1479 KiB  
Article
Unlock Happy Interactions: Voice Assistants Enable Autonomy and Timeliness
by Linlin Mo, Liangbo Zhang, Xiaohui Sun and Zhimin Zhou
J. Theor. Appl. Electron. Commer. Res. 2024, 19(2), 1013-1033; https://doi.org/10.3390/jtaer19020053 (registering DOI) - 30 Apr 2024
Abstract
This study examines the effects of three interactive voice assistant (VA) features (responsiveness, ubiquitous connectivity, and personalization) on consumer happiness. An online survey was administered to 316 VA consumers, and the data were analyzed using structural equation modeling with SmartPLS 4 software. The [...] Read more.
This study examines the effects of three interactive voice assistant (VA) features (responsiveness, ubiquitous connectivity, and personalization) on consumer happiness. An online survey was administered to 316 VA consumers, and the data were analyzed using structural equation modeling with SmartPLS 4 software. The results indicate that VA responsiveness, ubiquitous connectivity, and personalization have significant effects on consumer happiness. This study also provides evidence that consumer happiness is influenced by VA features through the mediating roles of autonomy and timeliness. Notably, perceived privacy risk has a dual effect, negatively affecting happiness but positively moderating the relationship between autonomy and happiness, suggesting a complex interplay between benefits and concerns in user interactions with VAs. This study highlights the need for VA businesses to consider both the enhancing and mitigating factors of technology for user experiences. Furthermore, our findings have significant implications for VA businesses and executives, suggesting that improved interactions through these VA features can better serve consumers and enhance their experiences. Full article
(This article belongs to the Topic Consumer Psychology and Business Applications)
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21 pages, 384 KiB  
Article
Corporate Risk-Taking, Innovation Efficiency, and High-Quality Development: Evidence from Chinese Firms
by Yongxia Wu, Haiqing Hu and Meng Xue
Systems 2024, 12(5), 154; https://doi.org/10.3390/systems12050154 - 30 Apr 2024
Abstract
Facing the increasingly complex and uncertain external environment, the reasonable control of investment risk is the key to realizing the sound operation and high-quality development of enterprises. Based on the innovation perspective, this paper takes A-share non-financial listed companies from 2007 to 2021 [...] Read more.
Facing the increasingly complex and uncertain external environment, the reasonable control of investment risk is the key to realizing the sound operation and high-quality development of enterprises. Based on the innovation perspective, this paper takes A-share non-financial listed companies from 2007 to 2021 as the research sample to explore the impact of the corporate risk-taking level on the high-quality development of enterprises and examines the transmission mechanism of the relationship between the two from the perspectives of innovation efficiency, innovation input, and innovation output. It is found that enterprise risk-taking significantly inhibits the high-quality development of enterprises, by reducing innovation efficiency; innovation efficiency plays a mediating role in the influence of the relationship between the two, which is mainly due to the fact that enterprise risk-taking increases the innovation inputs of enterprises but reduces the innovation outputs of enterprises, and then reduces the innovation efficiency of enterprises and inhibits the high-quality development of enterprises. This heterogeneity study finds that the inhibitory effect of corporate risk-taking on the high-quality development of firms is more pronounced among manufacturing firms, small-scale firms, and firms with higher capital intensity. The findings of this study provide both guidance to help enterprises to reduce risky investment decision-making behaviors and experience for regulators to effectively promote the formulation of policies related to the high-quality development of the real economy. Full article

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