Applied Sciences

55 pages, 5178 KiB

Open AccessReview

There Is Not Only Cupressus sempervirens L.: A Review on the Phytochemistry and Bioactivities of the Other Cupressus L. Species

by Claudio Frezza, Daniela De Vita, Fabio Sciubba, Chiara Toniolo, Lamberto Tomassini, Marcello Nicoletti, Marco Franceschin, Marcella Guiso, Armandodoriano Bianco, Mauro Serafini and Sebastiano Foddai

Appl. Sci. 2022, 12(14), 7353; https://doi.org/10.3390/app12147353 - 21 Jul 2022

Cited by 11 | Viewed by 4022

Abstract

This review article reports for the first time phytochemistry, ethnobotanical uses and pharmacological activities of all Cupressus L. species other than Cupressus sempervirens L. Indeed, the literature survey showed how many other Cupressus species are rich of important phytochemical compounds, widely used in [...] Read more.

This review article reports for the first time phytochemistry, ethnobotanical uses and pharmacological activities of all Cupressus L. species other than Cupressus sempervirens L. Indeed, the literature survey showed how many other Cupressus species are rich of important phytochemical compounds, widely used in the ethnobotanical field for several purposes and endowed with interesting biological activities, even if they are somehow neglected by the scientific community. This review aims to continue the study of these other Cupressus species and promote more research on them. Full article

(This article belongs to the Special Issue Plants: From Farm to Food and Biomedical Applications)

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11 pages, 1742 KiB

Open AccessArticle

Influences of Breathing Exercises and Breathing Exercise Combined with Aerobic Exercise on Changes in Basic Spirometry Parameters in Patients with Bronchial Asthma

by Ľuboš Grznár, Dávid Sucháň, Jana Labudová, Lukáš Odráška and Ivan Matúš

Appl. Sci. 2022, 12(14), 7352; https://doi.org/10.3390/app12147352 - 21 Jul 2022

Cited by 1 | Viewed by 3545

Abstract

Scientific evidence shows that breathing or aerobic programs can improve the quality of life of asthma patients. The aim of this work was to find out the influences of breathing exercises and breathing exercises combined with aerobic exercise on changes in spirometry parameters [...] Read more.

Scientific evidence shows that breathing or aerobic programs can improve the quality of life of asthma patients. The aim of this work was to find out the influences of breathing exercises and breathing exercises combined with aerobic exercise on changes in spirometry parameters in patients with bronchial asthma. Participants: The group consisted of 33 women with bronchial asthma—mild to moderate persistent levels of FEV1 reduction (80–50%)—with a mean age of 34.73 ± 1.53 years. They were randomly assigned to experimental group 1 (EX1), experimental group 2 (EX2) or the control group (CG). Materials and methods: Changes in spirometry parameters were evaluated over a 16-week period in the three groups: CG (placebo), EX1 (breathing exercises) and EX 2 (combination of breathing exercises with an aerobic program). To evaluate the pre-training and post-training diagnostics, we used MIR Spirobank II. The influences of the experimental and control factors were assessed using the following dependent variables: forced vital capacity (FVC), forced expiratory volume in one second (FEV1), Tiffeneau–Pinelli index (FEV1/FVC ratio), peak expiratory flow (PEF) and forced mid-expiratory flow (FEF25–75%). We used the Wilcoxon t-test and the Kruskal–Wallis test to evaluate the differences in the measured parameters. To examine the effect of our protocols, we used effect size (ES). Results: In CG we observed improvements in: FVC—(5%; p < 0.05; ES = 0.437). FEV1—(7.33%; p < 0.01; ES = 0.585). FEV1/FVC ratio (5.27%; p < 0.01; ES = 0.570). PEF (11.22%; p < 0.01; ES = 0.448). FEF25–75% (7.02%; p < 0.01; ES = 0.628). In EX1 we observed improvements in: FVC (5.23%; p < 0.01; ES = 0.631), FEV1 (20.67%; p < 0.01; ES = 0.627), FEV1/FVC ratio (16.06%; p < 0.01; ES = 0.628), PEF (13.35%; p < 0.01; ES = 0.627) and FEF25–75% (13.75%; p < 0.01; ES = 0.607). In EX2 we observed improvements in: FVC (9.12%; p < 0.01; ES = 0.627), FEV1 (27.37%; p < 0.01; ES = 0.626), FEV1/FVC ratio (15.32%; p < 0.01; ES = 0.610), PEF (30.66%; p < 0.01; ES = 0.626) and FEF25–75% (58.99%; p < 0.01; ES = 0.626). Significant differences compared to the control group were observed in EX1 for FEV1 (p < 0.05) and FEV1/FVC ratio (p < 0.01); and in EX2 for FEV1 (p < 0.05), FEV1/FVC ratio (p < 0.01), PEF (p < 0.05) and FEF (p < 0.05). A significant difference between EX1 and EX2 was observed in PEF (p < 0.05). Conclusions: It appears to be that combination of breathing exercises with aerobic activities is a more beneficial option for patients with bronchial asthma. Full article

(This article belongs to the Special Issue Cognition and Motion: Sensory Processing and Motor Skill Performance in Athletic Training and Rehabilitation)

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17 pages, 4504 KiB

Open AccessArticle

Research on Interface Slip Characteristics of Heritage Composite Timber Columns under Inclined Deformation

by Peng Chang, Qiuge Feng, Nannan Wu and Na Yang

Appl. Sci. 2022, 12(14), 7351; https://doi.org/10.3390/app12147351 - 21 Jul 2022

Viewed by 1629

Abstract

In order to study the mechanical performance and friction slip mechanism of the interface of a composite timber column under inclined deformation, the unilateral contact mechanical model of an ancient composite timber column under inclined deformation is proposed in this paper. According to [...] Read more.

In order to study the mechanical performance and friction slip mechanism of the interface of a composite timber column under inclined deformation, the unilateral contact mechanical model of an ancient composite timber column under inclined deformation is proposed in this paper. According to the limit of the inclination angle of slip point and the limit of the inclination angle of slip surface, the failure modes of the combination’s interface can be divided into three stages: the fully sticky stage, the partially sticky stage and the sliding stage. The theoretical results of the sliding displacement and shear stiffness of the combination’s interface under the effect of iron hoops were obtained by using the elastic mechanics method. Based on the shear sliding test of a composite timber column’s interface under the effect of iron hoops, the influences of different parameters on the shear sliding performance of the combination’s interface were investigated. The test results show that the number and the spacing of the iron hoops and the inclination angle of the interface are important factors affecting the shear strength of the combination’s interface. The shear strength of the interface increased with the increase in the number of iron hoops and the inclination angle of the interface. Since hoop spacing that is too large or too small cannot effectively improve the shear capacity of the interface, there is an optimal value for the hoop spacing. Full article

(This article belongs to the Special Issue Design and Assessment of Timber Structures)

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16 pages, 5895 KiB

Open AccessArticle

Parallel Accelerated Fifth-Order WENO Scheme-Based Pipeline Transient Flow Solution Model

by Tiexiang Mo and Guodong Li

Appl. Sci. 2022, 12(14), 7350; https://doi.org/10.3390/app12147350 - 21 Jul 2022

Cited by 1 | Viewed by 1628

Abstract

The water hammer phenomenon is the main problem in long-distance pipeline networks. The MOC (Method of characteristics) and finite difference methods lead to severe constraints on the mesh and Courant number, while the finite volume method of the second-order Godunov scheme has limited [...] Read more.

The water hammer phenomenon is the main problem in long-distance pipeline networks. The MOC (Method of characteristics) and finite difference methods lead to severe constraints on the mesh and Courant number, while the finite volume method of the second-order Godunov scheme has limited intermittent capture capability. These methods will produce severe numerical dissipation, affecting the computational efficiency at low Courant numbers. Based on the lax-Friedrichs flux splitting method, combined with the upstream and downstream virtual grid boundary conditions, this paper uses the high-precision fifth-order WENO scheme to reconstruct the interface flux and establishes a finite volume numerical model for solving the transient flow in the pipeline. The model adopts the GPU parallel acceleration technology to improve the program’s computational efficiency. The results show that the model maintains the excellent performance of intermittent excitation capture without spurious oscillations even at a low Courant number. Simultaneously, the model has a high degree of flexibility in meshing due to the high insensitivity to the Courant number. The number of grids in the model can be significantly reduced and higher computational efficiency can be obtained compared with MOC and the second-order Godunov scheme. Furthermore, this paper analyzes the acceleration effect in different grids. Accordingly, the acceleration effect of the GPU technique increases significantly with the increase in the number of computational grids. This model can support efficient and accurate fast simulation and prediction of non-constant transient processes in long-distance water pipeline systems. Full article

(This article belongs to the Special Issue Applied Hydrodynamics)

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14 pages, 10285 KiB

Open AccessReview

Fast Variable-Temperature Cryogenic Blackbody Sources for Calibration of THz Superconducting Receivers

by Mikhail Tarasov, Aleksandra Gunbina, Artem Chekushkin, Mikhail Strelkov and Valerian Edelman

Appl. Sci. 2022, 12(14), 7349; https://doi.org/10.3390/app12147349 - 21 Jul 2022

Cited by 2 | Viewed by 1987

Abstract

An electrically heated blackbody radiation source comprising thin metal film on a dielectric substrate and an integrating cavity was designed, fabricated, and experimentally studied at frequencies from 75 to 500 GHz. Analytical and numerical modeling were performed to optimize the emissivity, spectral uniformity, [...] Read more.

An electrically heated blackbody radiation source comprising thin metal film on a dielectric substrate and an integrating cavity was designed, fabricated, and experimentally studied at frequencies from 75 to 500 GHz. Analytical and numerical modeling were performed to optimize the emissivity, spectral uniformity, and modulation frequency of the radiation source with the spherical integrating cavity and thin film absorber. The blackbody emissivity (absorptivity) increased from 0.3 to 0.5 for the bare thin film on dielectric substrate, and up to 0.95 when it was placed inside the integrating cavity. The fabricated source mounted at the 0.5 K stage was used to measure the response time of a few microseconds and for sensitivity measurement down to 10⁻¹⁸ W/Hz^1/2 of the superconductor–insulator–normal metal–insulator–superconductor (SINIS) detector at 100 mK. Full article

(This article belongs to the Special Issue Applied Superconducting Electronics)

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18 pages, 6376 KiB

Open AccessArticle

Crushing Analysis and Optimization of Adjacent Variable Thickness Hexagonal Tubes

by Kai Xu, Ping Xu, Jie Xing, Shuguang Yao and Qi Huang

Appl. Sci. 2022, 12(14), 7348; https://doi.org/10.3390/app12147348 - 21 Jul 2022

Viewed by 1636

Abstract

In this study, we proposed a new adjacent variable thickness hexagonal tube (AVTHT) and performed crushing analysis and crashworthiness optimization under multiple loadings. First, the finite element models were constructed and validated by experiments with four configurations of AVTHTs. Then, the numerical simulations [...] Read more.

In this study, we proposed a new adjacent variable thickness hexagonal tube (AVTHT) and performed crushing analysis and crashworthiness optimization under multiple loadings. First, the finite element models were constructed and validated by experiments with four configurations of AVTHTs. Then, the numerical simulations under axial loading and multiple oblique loadings indicated that AVTHTs under various loading angles (0°, 10°, 20°, and 30°) and three patterns (α, β, and θ) exhibited different deformation modes, force-displacement characteristics, and crashworthiness indices. This suggested that we could change and determine the plate thickness configuration to make the AVTHTs exhibit the expected crushing performance under multiple loadings. Therefore, multi-objective optimization for minimizing maximum crushing force with multiple loadings (F_maxw) and maximizing specific energy absorption with multiple loadings (SEA_w) by changing the thickness configuration under multiple loadings was conducted. The results determined the thickness design domains and indicated that certain thickness ranges should be avoided, such as the ranges of

1.55 \leq t 1 \leq 1.6

and

1.85 \leq t 1 \leq 1.95

, which was helpful for getting AVTHTs to achieve excellent crushing performance in railway vehicles. In the pareto results, increasing t1 would not always increase the F_maxw and SEA_w. For example, when

1.75 \leq t 1 \leq 1.8

, increasing t1 would lead to decline of F_maxw and SEA_w. Full article

(This article belongs to the Section Mechanical Engineering)

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14 pages, 3083 KiB

Open AccessArticle

Evaluation of Biobed Bio-Mixture from Olive Oil Mill Wastewater Treatment as a Soil Organic Amendment in a Circular Economy Context

by Vasiliki Kinigopoulou, Evangelos Hatzigiannakis, Athanasios Guitonas, Efstathios K. Oikonomou, Stefanos Stefanou and Dionisios Gasparatos

Appl. Sci. 2022, 12(14), 7347; https://doi.org/10.3390/app12147347 - 21 Jul 2022

Cited by 3 | Viewed by 2024

Abstract

This study, based on circular economy principles and sustainable development practices, aims to present the results of soil samples analysis after their mixture with a biobed bio-mixture of straw, soil and compost, used for two consecutive years as organic bio-filter of olive oil [...] Read more.

This study, based on circular economy principles and sustainable development practices, aims to present the results of soil samples analysis after their mixture with a biobed bio-mixture of straw, soil and compost, used for two consecutive years as organic bio-filter of olive oil mill wastewater. So far, exhausted bio-mixtures used in biobeds to minimize pesticide point-source contamination turned out to contain residues of pesticides, and they are considered hazardous wastes; thus, they require special treatment before their disposal. Contrariwise, saturated bio-mixtures from bio-bed systems utilized for olive mill wastewater (OMWW) treatment not only do not require any special treatment before their final disposal but also can be exploited as a soil amendment. To this end, the effects of the used bio-mixture application in three different proportions as a soil amendment on the physical and chemical properties of medium-texture soil were investigated. The application of water simulating a typical irrigation period during a growing season took place. Upon completion of the water application, soil samples were collected from two different depths of the columns and analyzed, and leachates collected from the columns were also analyzed. Soil texture, organic matter, calcium carbonate, electrical conductivity (EC), pH, total nitrogen, nitrates, nitrites, ammonium, available phosphorus, exchangeable potassium, sodium, calcium and magnesium, exchangeable sodium percentage (ESP), cation exchange capacity (CEC), available iron, manganese, copper, zinc and boron were monitored in the soil samples as indexes of potential soil amendment, and EC, pH, nitrates, potassium, sodium, calcium, magnesium, sodium adsorption ratio (SAR), total hardness, iron, manganese, copper, zinc and boron were monitored in the leachates as indexes of potential groundwater contamination.The study demonstrated the effective use of saturated bio-mixture as an organic soil amendment, while the impact of selected amendments on groundwater was the minimum. Full article

(This article belongs to the Special Issue Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 2926 KiB

Open AccessArticle

A Novel Method for Fault Diagnosis of Bearings with Small and Imbalanced Data Based on Generative Adversarial Networks

by Qingbin Tong, Feiyu Lu, Ziwei Feng, Qingzhu Wan, Guoping An, Junci Cao and Tao Guo

Appl. Sci. 2022, 12(14), 7346; https://doi.org/10.3390/app12147346 - 21 Jul 2022

Cited by 16 | Viewed by 2479

Abstract

The data-driven intelligent fault diagnosis method of rolling bearings has strict requirements regarding the number and balance of fault samples. However, in practical engineering application scenarios, mechanical equipment is usually in a normal state, and small and imbalanced (S & I) fault samples [...] Read more.

The data-driven intelligent fault diagnosis method of rolling bearings has strict requirements regarding the number and balance of fault samples. However, in practical engineering application scenarios, mechanical equipment is usually in a normal state, and small and imbalanced (S & I) fault samples are common, which seriously reduces the accuracy and stability of the fault diagnosis model. To solve this problem, an auxiliary classifier generative adversarial network with spectral normalization (ACGAN-SN) is proposed in this paper. First, a generation module based on a deconvolution layer is built to generate false data from Gaussian noise. Second, to enhance the training stability of the model, the data label information is used to make label constraints on the generated fake data under the basic GAN framework. Spectral normalization constraints are imposed on the output of each layer of the neural network of the discriminator to realize the Lipschitz continuity condition so as to avoid vanishing or exploding gradients. Finally, based on the generated data and the original S & I dataset, seven kinds of bearing fault datasets are made, and the prediction results of the Bi-directional Long Short-Term Memory (BiLSTM) model is verified. The results show that the data generated by ACGAN-SN can significantly promote the performance of the fault diagnosis model under the S & I fault samples. Full article

(This article belongs to the Special Issue Diagnostics of Rotating Machinery through Vibration Monitoring: Signal Processing and Pattern Analysis)

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2 pages, 174 KiB

Open AccessEditorial

Special Issue on Materials and Technologies in Oral Research

by Morena Petrini and Stefano Gennai

Appl. Sci. 2022, 12(14), 7345; https://doi.org/10.3390/app12147345 - 21 Jul 2022

Viewed by 1184

Abstract

The introduction of novel materials and technologies in oral research has permitted the rapid evolution of dentistry, as confirmed by the increasing number of publications on this topic [...] Full article

(This article belongs to the Special Issue Materials and Technologies in Oral Research)

17 pages, 5795 KiB

Open AccessArticle

Mechanical Behaviors of Existing Large-Diameter Tunnel Induced by Horseshoe-Shaped Undercrossing Twin Tunnels in Gravel

by Jianye Li, Qian Fang, Xiang Liu, Jianming Du, Gan Wang and Jun Wang

Appl. Sci. 2022, 12(14), 7344; https://doi.org/10.3390/app12147344 - 21 Jul 2022

Cited by 5 | Viewed by 1994

Abstract

This article investigates and presents a case study on the Beijing Subway Line 12 excavation beneath the existing Qinghuayuan Tunnel. The composite pre-reinforcement technique was used in conjunction with the shallow tunneling method to control the distortion of the existing large-diameter tunnel. When [...] Read more.

This article investigates and presents a case study on the Beijing Subway Line 12 excavation beneath the existing Qinghuayuan Tunnel. The composite pre-reinforcement technique was used in conjunction with the shallow tunneling method to control the distortion of the existing large-diameter tunnel. When building twin tunnels underneath, this strategy considerably decreased the impact on the existing large-diameter tunnel. To systematically study the mechanical response of the existing large-diameter tunnel, a variety of sensors was embedded in the prefabricated segments just above the new twin tunnels. During the undercrossing twin tunnels procedure, the earth pressure, tunnel crown settlement, opening width of the segment joint, and the circumferential strain of the large-diameter existing tunnel were all measured. The settlement development of the existing large-diameter tunnel was categorized under six stages: (1) sedimentation, (2) heave, (3) second sedimentation, (4) second heave, (5) third sedimentation, and (6) steady state. The joint opening of the existing large-diameter tunnel changed sharply during the new undercrossing twin tunnels. The earth pressure and concrete stress of the linings rapidly increased during the new undercrossing twin tunnels. The majority of the reinforcement and concrete stresses were compressive and far lower than the yield strength, indicating that the tunnel was in a safe working condition. Full article

(This article belongs to the Special Issue Deep Rock Mass Engineering: Excavation, Monitoring, and Control)

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10 pages, 278 KiB

Open AccessArticle

Physical Development Differences between Professional Soccer Players from Different Competitive Levels

by Cíntia França, Andreas Ihle, Adilson Marques, Hugo Sarmento, Francisco Martins, Ricardo Henriques and Élvio Rúbio Gouveia

Appl. Sci. 2022, 12(14), 7343; https://doi.org/10.3390/app12147343 - 21 Jul 2022

Cited by 8 | Viewed by 2910

Abstract

In soccer, physical development is crucial for developing optimal performance. This study aimed to assess and compare the physical development of elite and non-elite professional soccer players. Seventy-eight male professional football players divided into four competitive levels participated in this study: the elite [...] Read more.

In soccer, physical development is crucial for developing optimal performance. This study aimed to assess and compare the physical development of elite and non-elite professional soccer players. Seventy-eight male professional football players divided into four competitive levels participated in this study: the elite group (EG), the non-elite group A (NEG-A), the non-elite group B (NEG-B), and the under 23 group (U23). Body composition, static strength, lower-body explosive strength, flexibility, and balance were assessed. No significant statistical differences between elite and non-elite players were seen in body composition parameters. However, the EG performed better in static strength, lower-body explosive strength, flexibility, and balance, even after adjusting for the effects of chronological age. The analysis showed that the competitive level (group) explained 25% to 29% of the variance observed in the lower-body explosive strength tasks. Sports staff and coaches in different age categories or competitive levels should include specific lower-body explosive strength content during soccer training to promote players’ long-term development towards the elite level. Full article

(This article belongs to the Special Issue New Trends in Fitness and Sports Performance Analysis)

11 pages, 28404 KiB

Open AccessArticle

Development of a Novel Gear-like Disk Resonator Applied in Gyroscope

by Liutao Gu, Weiping Zhang, Jun Feng and Zhihan Zhang

Appl. Sci. 2022, 12(14), 7342; https://doi.org/10.3390/app12147342 - 21 Jul 2022

Cited by 2 | Viewed by 1531

Abstract

This paper proposes a novel gear-like disk resonator (GDR). The design, fabrication, and characterization of GDR are presented. In comparison with a ring-like disk resonator (RDR), a GDR replaces the circular rings with meander-shaped rings consisting of linear beams. The finite element method [...] Read more.

This paper proposes a novel gear-like disk resonator (GDR). The design, fabrication, and characterization of GDR are presented. In comparison with a ring-like disk resonator (RDR), a GDR replaces the circular rings with meander-shaped rings consisting of linear beams. The finite element method (FEM) is implemented, and the simulation results show that the GDR has a much lower frequency and effective stiffness, higher quality factor (Q), and better immunity to crystal orientation error. Affected by high Q and small frequency splits, the mechanical sensitivity (S_mech) is shown to increase greatly. GDR and RDR with the same structure parameters are built side-by-side on the same wafer, and prototypes are fabricated through the SOI fabrication technique. The frequency response test and ring-down test are implemented using a readout circuit under a vacuum condition (5 Pa) at room temperature. The frequency split (9.1 Hz) of the GDR is about 2.8 times smaller than that (25.8 Hz) of the RDR without electrostatic tuning. Compared with the RDR, the Q (19.2 k) and decay time constant (0.59 s) of the GDR are improved by 145% and 236%, respectively. The experimental results show great promise for the GDR being used as a gear-like disk resonator gyroscope (GDRG). Full article

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17 pages, 5181 KiB

Open AccessArticle

Screening Additives for Amending Compacted Clay Covers to Enhance Diffusion Barrier Properties and Moisture Retention Performance

by Min Wang, Jiaming Wen, Heng Zhuang, Weiyi Xia, Ningjun Jiang and Yanjun Du

Appl. Sci. 2022, 12(14), 7341; https://doi.org/10.3390/app12147341 - 21 Jul 2022

Cited by 4 | Viewed by 1712

Abstract

The cover systems in contaminated sites have some problems, including desiccation cracks, which would lead to degradation of the barrier performance. This study presented a systemic laboratory experimental investigation on the liquid–plastic limit, moisture retention, hydraulic conductivity (k), and gas diffusion [...] Read more.

The cover systems in contaminated sites have some problems, including desiccation cracks, which would lead to degradation of the barrier performance. This study presented a systemic laboratory experimental investigation on the liquid–plastic limit, moisture retention, hydraulic conductivity (k), and gas diffusion barrier properties of amended compacted clay by attapulgite and diatomite for controlling desiccation cracks and migration of water and volatile organic compounds (VOCs). The results showed that the attapulgite could enhance the moisture retention and liquid limit of amended compacted clay. Diatomite could reduce the gas diffusion coefficient (D_θ) significantly. The compacted clay amended by the dual-additives component of attapulgite and diatomite could enhance the liquid limit, moisture retention percent, gas barrier property, and hydraulic performance compared with the unamended clay. Based on the experimental data obtained, the dosage of additives was targeted to be 5%. The moisture retention percent of dual-additives (attapulgite 4% and diatomite 1%) amended clay increased by 82%, the k decreased by 25%, and the D_θ decreased by 42% compared with unamended clay. Scanning electron microscopy (SEM), BET-specific surface area test method (BET), Mercury Intrusion Porosimetry (MIP), and thermogravimetric analysis (TGA) indicated the enhancement mechanism of additives-amended compacted clay. Full article

(This article belongs to the Special Issue Advances in Soil Pollution and Geotechnical Environment)

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21 pages, 9049 KiB

Open AccessReview

Seismic Analysis of Slender Monumental Structures: Current Strategies and Challenges

by Maria Giovanna Masciotta and Paulo B. Lourenço

Appl. Sci. 2022, 12(14), 7340; https://doi.org/10.3390/app12147340 - 21 Jul 2022

Cited by 14 | Viewed by 2545

Abstract

The preservation and seismic risk mitigation of built cultural heritage is considered today as a major priority in the international political agenda. Among the great variety of heritage structures spread worldwide, masonry towers belong to one of the most vulnerable categories against earthquake [...] Read more.

The preservation and seismic risk mitigation of built cultural heritage is considered today as a major priority in the international political agenda. Among the great variety of heritage structures spread worldwide, masonry towers belong to one of the most vulnerable categories against earthquake actions due to their morphological and material singularity. The proper understanding of the structural behavior of these artefacts at the micro, meso and macro scales, combined with a thorough knowledge of the best analysis practices deriving from the shared experience of the scientific community working in this field, is a fundamental prerequisite to appropriately address their seismic assessment. In this context, the present work offers an extensive discussion on the major challenges that slender monumental towers pose in terms of characterization of their actual behavior under seismic actions. A critical appraisal of the principal analysis methods applicable to the study of these structures is also presented along with a brief review of the existing modelling strategies for their numerical representation. Relevant examples are discussed in support of each argument. In spite of being a relatively young discipline, earthquake engineering has made remarkable progress in the last years and appropriate modi operandi have been consolidating to tackle the seismic assessment of unconventional systems, such as slender heritage structures. The work is conceived in a format of interest for both practitioners and researchers approaching the seismic assessment of this type of structures, and for those in need of an overall practical review of the topic. Full article

(This article belongs to the Special Issue Advanced Seismic Evaluation of Relevant Architectures)

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27 pages, 9266 KiB

Open AccessArticle

Empirical Perturbation Analysis of Two Adversarial Attacks: Black Box versus White Box

by Raluca Chitic, Ali Osman Topal and Franck Leprévost

Appl. Sci. 2022, 12(14), 7339; https://doi.org/10.3390/app12147339 - 21 Jul 2022

Cited by 1 | Viewed by 1727

Abstract

Through the addition of humanly imperceptible noise to an image classified as belonging to a category

c_{a}

, targeted adversarial attacks can lead convolutional neural networks (CNNs) to classify a modified image as belonging to any predefined target class [...] Read more.

Through the addition of humanly imperceptible noise to an image classified as belonging to a category

c_{a}

, targeted adversarial attacks can lead convolutional neural networks (CNNs) to classify a modified image as belonging to any predefined target class

c_{t} \neq c_{a}

. To achieve a better understanding of the inner workings of adversarial attacks, this study analyzes the adversarial images created by two completely opposite attacks against 10 ImageNet-trained CNNs. A total of

2 \times 437

adversarial images are created by

{EA}^{target, C}

, a black-box evolutionary algorithm (EA), and by the basic iterative method (BIM), a white-box, gradient-based attack. We inspect and compare these two sets of adversarial images from different perspectives: the behavior of CNNs at smaller image regions, the image noise frequency, the adversarial image transferability, the image texture change, and penultimate CNN layer activations. We find that texture change is a side effect rather than a means for the attacks and that

c_{t}

-relevant features only build up significantly from image regions of size

56 \times 56

onwards. In the penultimate CNN layers, both attacks increase the activation of units that are positively related to

c_{t}

and units that are negatively related to

c_{a}

. In contrast to

{EA}^{target, C}

’s white noise nature, BIM predominantly introduces low-frequency noise. BIM affects the original

c_{a}

features more than

{EA}^{target, C}

, thus producing slightly more transferable adversarial images. However, the transferability with both attacks is low, since the attacks’

c_{t}

-related information is specific to the output layers of the targeted CNN. We find that the adversarial images are actually more transferable at regions with sizes of

56 \times 56

than at full scale. Full article

(This article belongs to the Special Issue Explainable Artificial Intelligence (XAI))

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12 pages, 4734 KiB

Open AccessArticle

Real-Time Object Tracking Algorithm Based on Siamese Network

by Wenjun Zhao, Miaolei Deng, Cong Cheng and Dexian Zhang

Appl. Sci. 2022, 12(14), 7338; https://doi.org/10.3390/app12147338 - 21 Jul 2022

Cited by 3 | Viewed by 2030

Abstract

Object tracking is aimed at tracking a given target that is only specified in the first frame. Due to the rapid movement and the interference of cluttered backgrounds, object tracking is a significant challenging issue in computer vision. This research put forward an [...] Read more.

Object tracking is aimed at tracking a given target that is only specified in the first frame. Due to the rapid movement and the interference of cluttered backgrounds, object tracking is a significant challenging issue in computer vision. This research put forward an innovative feature pyramid and optical flow estimation based on the Siamese network for object tracking, which is called SiamFP. The SiamFP jointly trains the optical flow and the tracking task under the Siamese network framework. We employ the optical flow network based on the pyramid correlation mapping to evaluate the movement information of the target in two contiguous frames, to increase the accuracy of the feature representation. Simultaneously, we adopt spatial attention as well as channel attention to effectively restrain the ambient noise, stress the target area, and better extract the features of the given object, so that the tracking algorithm has a higher success rate. The proposed SiamFP obtains state-of-the-art performance on OTB50, OTB2015, and VOT2016 benchmarks while exhibiting better real-time and robustness. Full article

(This article belongs to the Special Issue Selected Papers from FCPAE2022 and 4th International Conference on Artificial Intelligence and Advanced Manufacturing (AIAM2022))

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18 pages, 10204 KiB

Open AccessArticle

Design and Acceleration of Field Programmable Gate Array-Based Deep Learning for Empty-Dish Recycling Robots

by Zhichen Wang, Hengyi Li, Xuebin Yue and Lin Meng

Appl. Sci. 2022, 12(14), 7337; https://doi.org/10.3390/app12147337 - 21 Jul 2022

Cited by 5 | Viewed by 2051

Abstract

As the proportion of the working population decreases worldwide, robots with artificial intelligence have been a good choice to help humans. At the same time, field programmable gate array (FPGA) is generally used on edge devices including robots, and it greatly accelerates the [...] Read more.

As the proportion of the working population decreases worldwide, robots with artificial intelligence have been a good choice to help humans. At the same time, field programmable gate array (FPGA) is generally used on edge devices including robots, and it greatly accelerates the inference process of deep learning tasks, including object detection tasks. In this paper, we build a unique object detection dataset of 16 common kinds of dishes and use this dataset for training a YOLOv3 object detection model. Then, we propose a formalized process of deploying a YOLOv3 model on the FPGA platform, which consists of training and pruning the model on a software platform, and deploying the pruned model on a hardware platform (such as FPGA) through Vitis AI. According to the experimental results, we successfully realize acceleration of the dish detection using a YOLOv3 model based on FPGA. By applying different sparse training and pruning methods, we test the pruned model in 18 different situations on the ZCU102 evaluation board. In order to improve detection speed as much as possible while ensuring detection accuracy, for the pruned model with the highest comprehensive performance, compared to the original model, the comparison results are as follows: the model size is reduced from 62 MB to 12 MB, which is only 19% of the origin; the number of parameters is reduced from 61,657,117 to 9,900,539, which is only 16% of the origin; the running time is reduced from 14.411 s to 6.828 s, which is only less than half of the origin, while the detection accuracy is decreased from 97% to 94.1%, which is only less than 3%. Full article

(This article belongs to the Special Issue Hardware-Aware Deep Learning)

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13 pages, 15189 KiB

Open AccessArticle

Suspension Control and Characterization of a Variable Damping Magneto-Rheological Mount for a Micro Autonomous Railway Inspection Car

by Yaojung Shiao and Tan-Linh Huynh

Appl. Sci. 2022, 12(14), 7336; https://doi.org/10.3390/app12147336 - 21 Jul 2022

Cited by 4 | Viewed by 2005

Abstract

This paper aims to present a suspension control strategy for a semi-active mount with variable damping utilizing a smart magneto-rheological fluid (MRF), which will be applied in a micro autonomous railway inspection car as a primary suspension to protect the inspection equipment from [...] Read more.

This paper aims to present a suspension control strategy for a semi-active mount with variable damping utilizing a smart magneto-rheological fluid (MRF), which will be applied in a micro autonomous railway inspection car as a primary suspension to protect the inspection equipment from the large suspension vibration on rails. We proposed a new multi-pole structure design for a semi-active magneto-rheological mount (MR mount) that can provide both a high damping force and a wide damping force band. Firstly, the mathematical model of MR mount dynamics was derived; secondly, a skyhook control strategy was developed for the MR mount; and finally, a dynamic simulation problem using Matlab software was constructed to evaluate the performance of the MR mount. The dynamic simulation results showed that the proposed MR mount using a skyhook control strategy showed greater vibration isolation performance compared to conventional passive mounts. In particular, the absolute displacement, velocity, and acceleration of the detector device were reduced by 83.33%, 77%, and 70%, respectively. The suspension vibration transmitted to the inspection device also decreased significantly, compared to input oscillation (i.e., un-sprung mass oscillation). Specifically, the suspension vibration reduced by a half at the excitation frequency of 2-fold the natural frequency and by greater magnitudes at higher excitation frequencies. Full article

(This article belongs to the Topic Innovation of Applied System)

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19 pages, 6634 KiB

Open AccessArticle

Random Vibration Fatigue Life Analysis of Airborne Electrical Control Box

by Daqian Zhang and Yueyang Chen

Appl. Sci. 2022, 12(14), 7335; https://doi.org/10.3390/app12147335 - 21 Jul 2022

Cited by 3 | Viewed by 3063

Abstract

To study the influence of random vibration on the fatigue life of airborne equipment, an aircraft electrical control box was selected as the research object. First, finite element software was used to model the dynamics of the airborne electrical control box to investigate [...] Read more.

To study the influence of random vibration on the fatigue life of airborne equipment, an aircraft electrical control box was selected as the research object. First, finite element software was used to model the dynamics of the airborne electrical control box to investigate its mode frequencies. The accuracy of finite element simulations was verified by performing mode experiments. Second, the mode superposition method was used to analyze the flight direction (X axis), side direction (Y axis), and altitude direction (Z axis) random vibration responses of the electrical control box. The analysis results were combined with the Miner linear cumulative damage criterion and the Gaussian-distribution Steinberg method to estimate the fatigue life of the electrical control box in the three directions. Finally, the calculation results were verified by performing the random vibration durability test on the electrical control box. The finite element mode analysis results show good agreement with the vibration experiment results, and the maximum error is 13.4%, indicating that the finite element model established in this paper is acceptable. The fatigue life of the electrical control box in the three axes meets the user requirements, and random vibration along the side direction (Y axis) has the greatest impact on the fatigue life, which is consistent with the results of the actual experimental data. The research method can be extended to predict the fatigue life of other airborne equipment and thus has practical significance for structural design and reliability analysis of airborne equipment. Full article

(This article belongs to the Special Issue Machine Diagnostics and Vibration Analysis)

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25 pages, 12218 KiB

Open AccessArticle

Forecasting Transmission and Distribution System Flexibility Needs for Severe Weather Condition Resilience and Outage Management

by Magda Zafeiropoulou, Ioannis Mentis, Nenad Sijakovic, Aleksandar Terzic, Georgios Fotis, Theodoros I. Maris, Vasiliki Vita, Emmanouil Zoulias, Vladan Ristic and Lambros Ekonomou

Appl. Sci. 2022, 12(14), 7334; https://doi.org/10.3390/app12147334 - 21 Jul 2022

Cited by 40 | Viewed by 3753

Abstract

With the increase in the complexity of the topology of transmission and distribution systems, associated with the predictability in the management of the dispatch of prosumers, new techniques for state estimation, and application of metaheuristics are necessary. In the current work a pilot [...] Read more.

With the increase in the complexity of the topology of transmission and distribution systems, associated with the predictability in the management of the dispatch of prosumers, new techniques for state estimation, and application of metaheuristics are necessary. In the current work a pilot project in Greece that addresses the difficulties of congestion and balancing management that system operators face in the renewable energy sources era, in accordance with the OneNet’s architecture is described. Available resources of grid’s flexibility are identified, and the implementation of an integrated monitoring system based on weather conditions with an energy control and dispatch system in the Greek electricity grid is addressed. The document suggests that flexibility resources will derive through predictions that have been improved and efficient forecasts from increased spatial resolution Numerical Weather Predictions and integration of Artificial Intelligence preventing the power system of entering dangerous topological or operational states. Full article

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30 pages, 17266 KiB

Open AccessArticle

3D JPS Path Optimization Algorithm and Dynamic-Obstacle Avoidance Design Based on Near-Ground Search Drone

by Yuan Luo, Jiakai Lu, Yi Zhang, Qiong Qin and Yanyu Liu

Appl. Sci. 2022, 12(14), 7333; https://doi.org/10.3390/app12147333 - 21 Jul 2022

Cited by 9 | Viewed by 3842

Abstract

As various fields and industries have progressed, the use of drones has grown tremendously. The problem of path planning for drones flying at low altitude in urban as well as mountainous areas will be crucial for drones performing search-and-rescue missions. In this paper, [...] Read more.

As various fields and industries have progressed, the use of drones has grown tremendously. The problem of path planning for drones flying at low altitude in urban as well as mountainous areas will be crucial for drones performing search-and-rescue missions. In this paper, we propose a convergent approach to ensure autonomous collision-free path planning for drones in the presence of both static obstacles and dynamic threats. Firstly, this paper extends the jump point search algorithm (JPS) in three dimensions for the drone to generate collision-free paths based on static environments. Next, a parent node transfer law is proposed and used to implement the JPS algorithm for any-angle path planning, which further shortens the planning path of the drones. Furthermore, the optimized paths are smoothed by seventh-order polynomial interpolation based on minimum snap to ensure the continuity at the path nodes. Finally, this paper improves the artificial potential field (APF) method by a virtual gravitational field and 3D Bresenham’s line algorithm to achieve the autonomous obstacle avoidance of drones in a dynamic-threat conflict environment. In this paper, the performance of this convergent approach is verified by simulation experiments. The simulation results show that the proposed approach can effectively solve the path planning and autonomous-obstacle-avoidance problems of drones in low-altitude flight missions. Full article

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21 pages, 2602 KiB

Open AccessArticle

Parameter Identification of Lithium Battery Model Based on Chaotic Quantum Sparrow Search Algorithm

by Jing Hou, Xin Wang, Yanping Su, Yan Yang and Tian Gao

Appl. Sci. 2022, 12(14), 7332; https://doi.org/10.3390/app12147332 - 21 Jul 2022

Cited by 10 | Viewed by 1879

Abstract

An accurate battery model is of great importance for battery state estimation. This study considers the parameter identification of a fractional-order model (FOM) of the battery, which can more realistically describe the reaction process of the cell and provide more precise predictions. Firstly, [...] Read more.

An accurate battery model is of great importance for battery state estimation. This study considers the parameter identification of a fractional-order model (FOM) of the battery, which can more realistically describe the reaction process of the cell and provide more precise predictions. Firstly, an improved sparrow search algorithm combined with the Tent chaotic mapping, quantum behavior strategy and Gaussian variation is proposed to regulate the early population quality, enhance its global search ability and avoid trapping into local optima. The effectiveness and superiority are verified by comparing the proposed chaotic quantum sparrow search algorithm (CQSSA) with the particle swarm optimization (PSO), genetic algorithm (GA), grey wolf optimization algorithm (GWO), Dingo optimization algorithm (DOA) and sparrow search algorithm (SSA) on benchmark functions. Secondly, the parameters of the FOM battery model are identified using six algorithms under the hybrid pulse power characterization (HPPC) test. Compared with SSA, CQSSA has 4.3%, 5.9% and 11.5% improvement in mean absolute error (MAE), root mean square error (RMSE) and maximum absolute error (MaAE), respectively. Furthermore, these parameters are used in the pulsed discharge test (PULSE) and urban dynamometer driving schedule (UDDS) test to verify the adaptability of the proposed algorithm. Simulation results show that the model parameters identified by the CQSSA algorithm perform well in terms of the MAE, RMSE and MaAE of the terminal voltages under all three different tests, demonstrating the high accuracy and good adaptability of the proposed algorithm. Full article

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15 pages, 1331 KiB

Open AccessArticle

In Vitro and In Silico Studies to Assess Edible Flowers’ Antioxidant Activities

by Eftichia Kritsi, Thalia Tsiaka, Alexandros-George Ioannou, Vassiliki Mantanika, Irini F. Strati, Irene Panderi, Panagiotis Zoumpoulakis and Vassilia J. Sinanoglou

Appl. Sci. 2022, 12(14), 7331; https://doi.org/10.3390/app12147331 - 21 Jul 2022

Cited by 10 | Viewed by 2406

Abstract

The incorporation of edible flowers in the human diet and culinary preparations dates back to ancient times. Nowadays, edible flowers have gained great attention due to their health-promoting and nutritive effects and their widespread acceptance by consumers. Therefore, edible flowers are ideal candidates [...] Read more.

The incorporation of edible flowers in the human diet and culinary preparations dates back to ancient times. Nowadays, edible flowers have gained great attention due to their health-promoting and nutritive effects and their widespread acceptance by consumers. Therefore, edible flowers are ideal candidates for use in the design and development of functional foods and dietary supplements, representing a new and promising trend in the food industry. Thus, the present study attempts to assess the potential of various edible flowers against oxidative stress by applying a combination of in vitro, in silico and spectroscopic techniques. Specifically, the spectroscopic profiles of edible flower extracts were evaluated using ATR-FTIR spectroscopy, while their total phenolic contents and antioxidant/antiradical activities were determined spectrophotometrically. The most abundant phytochemicals in the studied flowers were examined as enzyme inhibitors through molecular docking studies over targets that mediate antioxidant mechanisms in vivo. Based on the results, the red China rose followed by the orange Mexican marigold exhibited the highest TPCs and antioxidant activities. All samples showed the characteristic FTIR band of the skeletal vibration of phenolic aromatic rings. Phenolic compounds seem to exhibit antioxidant activity with respect to NADPH oxidase, myeloperoxidase (MP), cytochrome P450 and, to a lesser extent, xanthine oxidase (XO) enzymes. Full article

(This article belongs to the Special Issue Phytochemicals and Antioxidant Properties of Edible Plants)

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17 pages, 9853 KiB

Open AccessArticle

A Metal Detector for Clip Location Tracking of Stomach and Colon Cancer during Laparoscopic Surgery

by Kicheol Yoon, Jun-Won Chung and Kwang Gi Kim

Appl. Sci. 2022, 12(14), 7330; https://doi.org/10.3390/app12147330 - 21 Jul 2022

Cited by 2 | Viewed by 3628

Abstract

In laparoscopic surgery for colorectal and gastric cancer, it is difficult to locate the tumor in the cavity for excision. Tumors in the colon or stomach are blocked by mucous membranes; thus, the view from the cavity is obscured. Therefore, to determine the [...] Read more.

In laparoscopic surgery for colorectal and gastric cancer, it is difficult to locate the tumor in the cavity for excision. Tumors in the colon or stomach are blocked by mucous membranes; thus, the view from the cavity is obscured. Therefore, to determine the location of the tumor, a marker can be installed around the tumor and the location of the tumor can be found using a sensor. Until now, most of the clip-detectors that have been developed can detect the location of tumors for either colorectal or gastric cancer. The research on the development of a detector that can detect the location of tumors for both colorectal and gastric cancer, is insufficient. Most detectors for tumor location determination are devised using a magnet by connecting a wire to a clip. In this method, the position of the magnet moves along the length of the wire. Therefore, it is difficult for the detector to detect the exact location of the tumor. Based on this method, this study designs a clip maker to determine the location of a tumor and a detector that can detect the clip. The clip and the sensing element are directly connected. The clip is developed using ferrite and coil to generate a magnetic field induced by an eddy current in the metal (clip), and the detector is designed using the Colpitts oscillator to induce a magnetic field. After installing the prepared clip at the tumor location, the detector is used to detect the clip, and accordingly, the location of the tumor can be identified using the detector. To test the performance of the clip and detector, we conducted animal experiments. In the course of the animal experiment, four clips were installed in the colon and stomach, and we succeeded in detecting all the clips. Because the clip-detector is used to locate the tumor during laparoscopic surgery, an endoscope must be used. Therefore, it is predicted that the demand for laparoscopic surgery and endoscopic medical industry will increase because of the clip-detector. Full article

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13 pages, 9957 KiB

Open AccessArticle

Response of Osteoblasts to Electric Field Line Patterns Emerging from Molecule Stripe Landscapes

by Christian Voelkner, Issam Assi, Willi Karberg, Regina Lange, Sven Neuber, Christiane A. Helm, Martina Gruening, J. Barbara Nebe, Ingo Barke and Sylvia Speller

Appl. Sci. 2022, 12(14), 7329; https://doi.org/10.3390/app12147329 - 21 Jul 2022

Viewed by 1756

Abstract

Molecular surface gradients can constitute electric field landscapes and serve to control local cell adhesion and migration. Cellular responses to electric field landscapes may allow the discovery of routes to improve osseointegration of implants. Flat molecule aggregate landscapes of amine- or carboxyl-teminated dendrimers, [...] Read more.

Molecular surface gradients can constitute electric field landscapes and serve to control local cell adhesion and migration. Cellular responses to electric field landscapes may allow the discovery of routes to improve osseointegration of implants. Flat molecule aggregate landscapes of amine- or carboxyl-teminated dendrimers, amine-containing protein and polyelectrolytes were prepared on glass to provide lateral electric field gradients through their differing zeta potentials compared to the glass substrate. The local as well as the mesoscopic morphological responses of adhered osteoblasts (MG-63) with respect to the stripes were studied by means of Scanning Ion Conductance Microscopy (SICM) and Fluorescence Microscopy, in situ. A distinct spindle shape oriented parallel to the surface pattern as well as a preferential adhesion of the cells on the glass site have been observed at a stripe and spacing width of 20

μ

m. Excessive ruffling is observed at the spindle poles, where the cells extend. To explain this effect of material preference and electro-deformation, we put forward a retraction mechanism, a localized form of double-sided cathodic taxis. Full article

(This article belongs to the Section Applied Physics General)

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16 pages, 3515 KiB

Open AccessArticle

Seepage Characteristics Study of Single Rough Fracture Based on Numerical Simulation

by Shidong Wang, Qing Zhang, Li Zhao, Yi Jin and Jiazhong Qian

Appl. Sci. 2022, 12(14), 7328; https://doi.org/10.3390/app12147328 - 21 Jul 2022

Cited by 2 | Viewed by 1906

Abstract

Fracture seepage is an important aspect of groundwater research, but due to the closure of fractures and the randomness of wall surface roughness, it is a challenge to carry out relevant research. Numerical simulation serves as a good way to solve this problem. [...] Read more.

Fracture seepage is an important aspect of groundwater research, but due to the closure of fractures and the randomness of wall surface roughness, it is a challenge to carry out relevant research. Numerical simulation serves as a good way to solve this problem. As such, the water flow in single fracture with different shapes and densities of roughness elements (various bulges/pits on fracture wall surfaces) on wall surface was simulated by Fluent software. The results show that, in wider rough fractures, the flow rate mainly depends on fracture aperture, while, in narrow and close rough fracture medium, the surface roughness of fracture wall is the main factor of head loss of seepage; there is a negative power exponential relation between the hydraulic gradient index and the average fracture aperture, i.e., with increase of rough fracture aperture, both the relative roughness of fracture and the influence of hydraulic gradient decrease; in symmetrical-uncoupled rough fractures, there is a super-cubic relation between the discharge per unit width and average aperture; the rough fracture permeability coefficient K is not a constant which is affected by the scale effect and the density of roughness elements. Results found provide further understanding of rough fracture seepage. Full article

(This article belongs to the Special Issue Fractured Reservoirs 2021)

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15 pages, 1073 KiB

Open AccessArticle

Cluster Thinning Improves Aroma Complexity of White Maraština (Vitis vinifera L.) Wines Compared to Defoliation under Mediterranean Climate

by Ana Mucalo, Katarina Lukšić, Irena Budić-Leto and Goran Zdunić

Appl. Sci. 2022, 12(14), 7327; https://doi.org/10.3390/app12147327 - 21 Jul 2022

Cited by 6 | Viewed by 2071

Abstract

Defoliation and cluster thinning are useful canopy management techniques to modulate grapevine carbon distribution and microclimate. Both techniques are directed to achieve the proper balance between fruit and foliage, and to maximize production of well-ripened fruits and quality wines. We performed five canopy [...] Read more.

Defoliation and cluster thinning are useful canopy management techniques to modulate grapevine carbon distribution and microclimate. Both techniques are directed to achieve the proper balance between fruit and foliage, and to maximize production of well-ripened fruits and quality wines. We performed five canopy treatments on Maraština grapevine grown at a commercial vineyard in the Vrgorac Valley region of Croatia: three different times of basal defoliation, cluster thinning at the veraison, and an untreated control. The effects of the canopy changes on the chemical composition of grapes and wines were studied. The treatments had variable impacts on yield components and basic wine composition. Volatile aroma compounds in produced wines were analyzed using gas chromatography–mass spectrometry coupled with a mass-selective detector. The concentrations of 70 of the 96 individual volatile compounds were significantly influenced by the canopy technique used. The concentrations of 58 of these compounds were different according the timing of defoliation. Cluster thinning at an intensity of 35% produced wines with more terpenes, esters, higher alcohols, other alcohols, volatile phenolic compounds, lactones, and other compounds than other treatments. Among terpenes, cluster thinning increased terpinen-4-ol, linalool, trans-β-farnesen, and geraniol. Odor activity value analysis revealed 16 volatile compounds that contributed to the aroma of cluster-thinned wines. Full article

(This article belongs to the Special Issue Polyphenol and Aroma Compounds in Viticulture and Enology)

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19 pages, 3835 KiB

Open AccessArticle

Study on Noise Model of an Automotive Axial Fan Based on Aerodynamic Load Force

by Yinhui Zhong, Yinong Li and Jun Li

Appl. Sci. 2022, 12(14), 7326; https://doi.org/10.3390/app12147326 - 21 Jul 2022

Viewed by 1915

Abstract

Due to the fact that the noise caused by axial fan blades of vehicles is large, which seriously affects ride comfort, and there is no effective mathematical model to quantitatively study the contribution of the various parameters of the blades to the noise, [...] Read more.

Due to the fact that the noise caused by axial fan blades of vehicles is large, which seriously affects ride comfort, and there is no effective mathematical model to quantitatively study the contribution of the various parameters of the blades to the noise, a new method for calculating the load force of the blades is proposed. This method obtains the constant load force of the blade according to the blade element momentum theory and the characteristics of the blade structure of the axial fan for a vehicle. At the same time, this method obtains the non-constant load force of the blade by combining the non-constant thin-wing theory and experimental data and then vectors the constant load force and the non-constant load force to obtain the total load force of the blade to build a mathematical model of the relationship between the noise of the fan and the parameters of the blade. According to the model, the total sound pressure level of a fan is calculated numerically and further compared with the FLUENT software simulation and experimental results. The results show that the error of the total sound pressure level calculated by the numerical value is within 3 dB(A). This method provides an important basis for the study of a high-accuracy noise mathematical model and the optimization of blade parameters of low Mach-number fans. Full article

(This article belongs to the Section Mechanical Engineering)

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32 pages, 8310 KiB

Open AccessArticle

Impact of the Choice of Available Brake Discs and Brake Pads at Different Prices on Selected Vehicle Features

by František Synák, Lenka Jakubovičová and Matúš Klačko

Appl. Sci. 2022, 12(14), 7325; https://doi.org/10.3390/app12147325 - 21 Jul 2022

Cited by 6 | Viewed by 3618

Abstract

The purpose of a road vehicle’s friction brakes is to convert a vehicle’s kinetic energy to thermal energy. When doing so, the brakes should not be heated to such temperatures at which their efficiency could be reduced. The objective of the measurements in [...] Read more.

The purpose of a road vehicle’s friction brakes is to convert a vehicle’s kinetic energy to thermal energy. When doing so, the brakes should not be heated to such temperatures at which their efficiency could be reduced. The objective of the measurements in this article is to assess the ability of passenger brakes’ spare parts, brake discs and brake pads to meet the requirements for brakes. For the experimental measurements, brake discs and brake pads of high, middle and low prices were selected from advertisements intended for a particular vehicle. The measurements were performed via driving test measurements as well as under laboratory conditions. Driving test measurements determined the brake distance and mean fully developed deceleration of the brake components of all three price categories. On the other hand, the dependence between the effort to control the steering and the brake force, as well as the temperature of brake discs during repeated interrupted braking and continuous uninterrupted braking, were determined under laboratory conditions. Attention was also given to prevention against corrosion. The results show a sufficient ability of all the brake pads and brake discs tested to generate braking force under common conditions. However, when using the lowest-priced brake discs and brake pads, a substantial reduction in their efficiency can occur if braking intensively or over a long period. Full article

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9 pages, 2197 KiB

Open AccessArticle

Age, Sex, and Maxillary Position Are Associated with Successful Microimplant-Assisted Rapid Palatal Expansion in Adults

by Jae-Hong Choi, Byung Gyu Gil, Yoon-Ji Kim and Dong-Yul Lee

Appl. Sci. 2022, 12(14), 7324; https://doi.org/10.3390/app12147324 - 21 Jul 2022

Viewed by 4784

Abstract

The purpose of this study was to investigate the possible predictors of success of microimplant-assisted rapid palatal expansion (MARPE) in skeletally mature patients. Additionally, factors associated with the amount of maxillary expansion were analyzed. Factors associated with MARPE success were analyzed in 53 [...] Read more.

The purpose of this study was to investigate the possible predictors of success of microimplant-assisted rapid palatal expansion (MARPE) in skeletally mature patients. Additionally, factors associated with the amount of maxillary expansion were analyzed. Factors associated with MARPE success were analyzed in 53 adult patients (27 males, 26 females, mean age 25.8 ± 8.9 years, and range 18.0 to 56.6 years) who had a maxillary transverse deficiency greater than 2 mm and a cervical vertebral maturation stage of 6. Age at pretreatment (T1), sex, sutural bone density at T1, type of appliance, mode of microimplant fixation, and lateral cephalometric variables at T1 were considered for inclusion as predictors for MARPE success. In patients who showed successful maxillary skeletal expansion, the linear distances of maxillary widths were measured on cone-beam-computed-tomography images at T1 and after MARPE (T2), and factors associated with the amount of expansion were analyzed. In total, 41 of the 53 patients showed successful maxillary expansion. Age (p = 0.019), sex (p = 0.002), and A-N perp (p = 0.015) were significantly associated with the success of MARPE. The factors associated with the amount of maxillary skeletal expansion were SN-MP and midpalatal-suture density at T1. In conclusion, there is a greater chance of failure in male patients who are older and have maxillary retrusion. A greater amount of maxillary expansion can be expected in patients with a higher mandibular-plane angle and with lower midpalatal-suture density. Full article

(This article belongs to the Special Issue Clinical Applications of Orthodontic TSADs (Temporary Skeletal Anchorage Devices))

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Appl. Sci., Volume 12, Issue 14 (July-2 2022) – 527 articles

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