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The extraction algorithm of target characteristics resonance set at the high-frequency band plays a significant role in defense applications like early warning. The paper proposes a new method to extract the characteristic resonance set of radar targets in the resonance frequency region using an autoregressive moving average model optimized by root mean square propagation particle swarm optimization. Considering that the total scattering response in the resonant region consists of early-time and late-time responses, the autoregressive moving average model approximate the total scattering responses to avoid errors caused by intercepting the late-time response. Further, the paper investigated the impact of the swarm optimization algorithm on the accuracy of moving average model parameters when obtaining the resonance set at different target aspects. The extracted characteristic resonance results within a range of azimuth directions through an aircraft target paradigm indicate that the new method is more convenient and precise than the matrix beam prediction method. [ABSTRACT FROM AUTHOR]

In recent years, the quantity of visible satellites has increased significantly due to multiple satellite systems that leaped forward. The BeiDou Navigation Satellite System (BDS) and Galileo satellite navigation system (Galileo) broadcast triple-frequency signals and above to users, thus enhancing the reliability, continuity, and availability of the single-epoch real-time kinematic (RTK) positioning. In this study, an improved single-epoch multifrequency multisystem RTK method is successfully developed for the medium-long baseline. First, the Galileo and BDS extra-wide-lane (EWL) ambiguities are fixed at a high success rate, and the Galileo and BDS wide-lane (WL) ambiguity is achieved via the transformation process. Second, the fixed WL ambiguities of Galileo and BDS are exploited to elevate the fixed rate of GPS WL ambiguity. Third, the parametric strategies for ionospheric delay are carried out to upregulate the narrow-lane (NL) ambiguity-fixed rate of GPS. Further, the real-time data are adopted for verifying the feasibility of the method developed in this study. The experimental results demonstrate the optimal carrier-to-noise density ratio (C/N0) of full operational capability (FOC) E5a/E5b at all frequencies, followed by IIR-M L1, and IIR-A/B L2 exhibits the worst performance. Generally, the multipath combination (MPC) of Galileo signals shows root mean square (RMS) values within 0.4 m, ordered as follows: E 1 > E 5 b > E 5 a. For the BDS-2, the B3 signal exhibits optimal performance, while the B1 signal is the worst. The RMS of MPC errors of L1 signals is smaller than the L2 signals for the GPS. Furthermore, under the 50 km baseline, the GPS NL ambiguity-fixed rate using the ionosphere-free (IF) combination reaches only 47.74% at the ratio threshold of 2. Finally, compared to the ionosphere-free combination method, the GPS NL ambiguity-fixed rate is increased by 45.52% with the presented method. The proposed approach broadens the future application of deformation monitoring in medium-long baseline scenarios. [ABSTRACT FROM AUTHOR]

Objective. MAPK3 activates several nuclear transcription factors, including c-Jun and c-fos, by phosphorylating its downstream cytoplasmic protein, thereby contributing to cell proliferation and survival. Different carcinomas' initiation, progression, cancer cell metastasis, and drug resistance have been associated with MAPK3 overexpression. Given the need for new and potent MAPK3 inhibitors, this study aimed to explore the potential of anthraquinones (AQs) as organic compounds capable of inhibiting MAPK3. Methods. Using AutoDock 4.0 software, the binding affinity of 21 AQs to the receptor's active site was evaluated. AQs were ranked based on their ΔGbinding values to the receptor's active site, with the highest rankings receiving the most favorable scores. The Discovery Studio Visualizer tool was used to demonstrate the interaction modes between the highest-ranked AQs and the MAPK3 catalytic site. Furthermore, a 100-nanosecond molecular dynamics (MD) computer simulation was performed to assess the stability of the docked pose of the most potent enzyme inhibitor identified in this study. Results. The binding affinity of emodin-8-glucoside, aloe-emodin 8-glucoside, pulmatin, rhodoptilometrin, and hypericin to the receptor's ATP binding cleft was noteworthy, as the ΔGbinding values were < − 10 kcal/mol. In addition, emodin-8-glucoside, aloe-emodin 8-glucoside, and pulmatin were found to have inhibition constant values at the picomolar concentration. According to our computer simulation results, the docked pose of emodin-8-glucoside within the active site of MAPK3 achieved a stable state after 70 ns. In other words, the root mean square deviation (RMSD) graph indicated stability within the 70–100 ns timeframe. Conclusion. Inhibition of MAPK3 by emodin-8-glucoside, aloe-emodin 8-glucoside, pulmatin, rhodoptilometrin, and hypericin may have therapeutic potential in cancer treatment. [ABSTRACT FROM AUTHOR]

Cycle slip determination plays an important role in high-precision data processing and application of global navigation satellite systems (GNSS). The TurboEdit method consists of the Melbourne-Wubbena (MW) and the geometry-free phase (GF) combination. It can correctly detect and repair cycle slip in most cases. Cycle slip detection (CSD) with GF is disturbed by severe ionospheric delay variations; moreover, CSD or cycle slip repair (CSR) with the MW faces the risk of the disturbance from large pseudorange errors. Hence, cycle slip determination would be difficult under some extreme conditions, e.g., cycle slips occur in low altitude satellite, low sampling rate of dual-frequency observations. To overcome the limitations, a new dual-frequency CSD and CSR method is proposed. The main contents are as follows: (1) compared with the MW method, the Doppler-assisted phase subtraction pseudorange (DAPSP) method that we proposed has no detection blind spot and can effectively reduce the influence of pseudorange noise at high sampling rates; thus, we replace MW by the DAPSP method to improve the detection accuracy. (2) An adaptive threshold model with root mean square (RMS) is established to effectively reduce the missing and false range detection of cycle slip. (3) The sliding polynomial fitting-assisted GF (SPFAGF) is carried out according to the satellite altitude angle. The trend of ionospheric delay and residual multipath effect error between adjacent epochs is extracted and suppressed by SPFAGF. The method combined with DAPSP and SPFAGF (DAPSP-SPFAGF) overcomes the situation that the TurboEdit method cannot effectively detect under extreme conditions. The experimental results of Beidou dual-frequency observation data show that the TurboEdit method and the DAPSP-SPFAGF method can perform CSD and CSR in most cases. At the sampling rate of 1 s, the detection speed of DAPSP-SPFAGF method is significantly faster than TurboEdit method. The number of false positives about CSD is reduced from 68 to 0. At the sampling rate of 30 s and under the condition of the observed satellite altitude angle below 30°, the false alarm rate of the DAPSP-SPFAGF method is 0, but the TurboEdit method's false alarm rate is 71.2%. So DAPSP-SPFAGF method is prior to the TurboEdit method at the high sampling rates or under extreme conditions, especially it can accurately detect and repair cycle slip and reduce the false positives and false alarm rate. [ABSTRACT FROM AUTHOR]

Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) satellites are used to map the gravity field of the Earth. The orbit accuracy of GRACE-FO depends on the quality of on-board GPS data, which is key factor affecting GRACE-FO mission execution. To improve the orbit accuracy of GRACE-FO, a dynamical method was developed to reprocess kinematic orbits. First, with known kinematic orbits, the least squares method was used to estimate the initial state and dynamical parameters of GRACE-FO orbits. Second, during data processing, orbit coordinates containing outliers were deleted. Finally, GRACE-FO dynamical orbits with high accuracy were determined by combining initial state and dynamical parameters. To assess the orbit accuracy, dynamical and kinematic orbits were compared with Jet Propulsion Laboratory (JPL) orbits. Three-dimensional root-mean-square (3D-RMS) results show dynamical and kinematic orbit accuracy of 6.3 and 9.5 cm for GRACE-FO-C and 6.6 and 9.7 cm for GRACE-FO-D, achieving improvements of 33.68% and 31.96%, respectively. The RMS of satellite laser range (SLR) residuals was about 4.1 and 5.1 cm for GRACE-FO-C dynamical and kinematic orbit accuracy, and about 4.2 and 5.4 cm for GRACE-FO-D. [ABSTRACT FROM AUTHOR]

Visual or haptic feedback based on error modulation has been used to improve the effect of robot-assisted rehabilitation training. However, there are several investigations on the effects of error modulation-based visual and haptic feedback fusion strategies on motor learning and motivation. To observe the influence of different feedback fusion strategies on motor learning and motivation, a parallel controlled study was conducted, dividing 30 healthy subjects into three groups with similar skill levels. The no error modulation group received visual and haptic feedback without error modulation; the visual amplification haptic reduction group received visual error amplification combined with haptic error reduction, and the visual reduction haptic amplification (VRHA) group received visual error reduction combined with haptic error amplification. Each subject implemented a trajectory-tracking task with an upper limb rehabilitation robot. They went through baseline, training, assessment, and generalization tests and completed 340 consecutive tracking movements. To evaluate motor learning and motivation, the average tracking error, the root mean square (RMS) of surface electromyography (sEMG) signals, and the intrinsic motivation inventory scale were all examined. In the assessment tests, the average tracking error was significantly decreased in all three groups. In particular, the VRHA group had a larger reduction in average tracking error in the generalization test, lower RMS of sEMG signals both in the assessment and generalization tests and higher perceived competence in the assessment tests. The VRHA fusion strategy significantly improved the subjects' motor learning and transfer ability, decreased muscle activation, and increased motor learning motivation. These findings may provide some new insights for multisensory feedback fusion technology in the application of rehabilitation robots. [ABSTRACT FROM AUTHOR]

This paper presents research results on semiactive suspension using a fuzzy logic controller. Firstly, a full car model is built with 7 degrees of freedom using a semiactive suspension system at all four wheels. The dynamic equations are converted to the state space representation to facilitate control design and improve accuracy in simulation design. Then, a two-layer parallel fuzzy logic controller is designed with 49 and 25 rules for two fuzzy inference systems. In this way, the fuzzy logic controller is able to respond to a wide operating range of the system and the output force is smoother. Finally, the evaluation results are performed in the frequency and time domains with a real random road profile, and they showed that the root mean square value of the signals when using a semiactive suspension system with the proposed fuzzy logic controller decreased by over 25% compared to the passive suspension system. This clearly demonstrates the effectiveness of the proposed controller in improving the ride comfort, the road holding and ensuring the suspension travel of cars. [ABSTRACT FROM AUTHOR]

The correlation filtering algorithm of infrared spectral data for dim and small target tracking is studied to improve the tracking accuracy of small and weak targets and to track small and weak targets in real time. After the image noise reduction processing by the mean shift filtering algorithm, the infrared small and weak target image data model is constructed by using the denoised infrared small and weak target image. And the brightness value and position of unknown small and weak targets are obtained. The tracking and measurement model of small and weak targets is built. The joint probabilistic data association algorithm is used to calculate the probability that each measurement is associated with its possible source targets, and the particle filter is used to update the tracking status of small and weak targets to achieve real-time tracking of small and weak targets. The experimental results show that the algorithm can enhance the edge contour information of small and weak images, so as to accurately track small and weak targets moving in any track, and has good real-time tracking and accuracy. There is a small deviation between the tracking track of weak and small targets tracked by the algorithm and the actual track, and the root mean square difference of tracking weak and small targets is within 2 pixels. In addition, the detection probability of detecting weak and small targets is less affected by SNR environmental factors. [ABSTRACT FROM AUTHOR]

Fly ash generated during boiler combustion are carried away with hot flue gas and deposited over the heat exchanger surfaces. This study was motivated by the decline in the thermal efficiency of the heat exchangers in thermal power plants due to ash fouling. The paper discusses a new computational procedure that has been attempted to identify the best statistical model for predicting heat exchanger fouling and also to choose the most strongly linked covariates. In this context, three different statistical models including multiple linear regression, sliced inverse regression, and random forests regression are used to estimate the cleanliness factor of the heat exchanger. The variables and model are chosen solely on the basis of analytical procedures. Heat exchanger metal tube temperature that highly influences the cleanliness factor is selected using a measure of importance based on random perturbations. Metal temperature above a threshold is selected as a strongly linked covariate. The R package modevarsel is used here to perform the statistical analysis. The value of root mean square error for the cleanliness factor from sliced inverse regression and random forest is 0.0002, indicating that as more feasible in predicting ash fouling. [ABSTRACT FROM AUTHOR]

Acinetobacter baumannii (A. baumannii) is an opportunistic bacterium that has developed multidrug resistance (MDR) to most of today's antibiotics, posing a significant risk to human health. Considering the fact that developing novel drugs is a time-consuming and expensive procedure, this research focuses on utilizing computational resources for repurposing antibacterial agents for A. baumannii. We targeted shikimate kinase, an essential enzyme in A. baumannii, that plays a significant role in the metabolic process. The basis for generating new therapeutic compounds is to inhibit the shikimate kinase and thereby targeting the shikimate pathway. Herein, 1941 drug-like compounds were investigated in different in silico techniques for assessing drug-likeness properties, ADMET (absorption, distribution, metabolism, excretion, and toxicity) profiling, binding affinity, and conformation analysis utilizing Autodock-vina and SwissDock. CHEMBL1237, CHEMBL1237119, CHEMBL2018096, and CHEMBL39167178 were determined as potential drug candidates for suppressing shikimate kinase protein. Molecular Dynamics Simulation (MDS) results for root mean square deviation, root mean square fluctuation, hydrogen bond, and gyration radius confirm the drug candidates' molecular stability with the target protein. According to this study, CHEMBL1237 (Lisinopril) could be the most suitable candidate for A. baumannii. Our investigation suggests that the inhibitors of shikimate kinase could represent promising treatment options for A. baumannii. However, further in vitro and in vivo studies are necessary to validate the therapeutic potential of the suggested drug candidates. [ABSTRACT FROM AUTHOR]

The hysteretic damping tuned mass damper (HD-TMD) is composed of a spring element, a hysteretic damping (HD) element, and a mass. The HD force is proportional to the displacement of the tuned mass damper (TMD). Recently, the application of HD-TMD has emerged, but its optimal design is still lacking. To fill this academic gap, numerical solutions for optimal parameters of HD-TMD subjected to white-noise excitation were obtained based on the H2 optimization criterion. Performance balance optimization with a weighting factor was carried out to improve the response of a structure with the HD-TMD system. A set of earthquake records and harmonic excitations were conducted to prove the effectiveness of the optimal numerical solutions and the performance balance design. It was found that the performance of the HD-TMD is slightly better than that of the traditional optimized TMD. As a real TMD application of HD-TMD, the variable friction pendulum TMD (VFP-TMD) was selected to experience earthquakes with the proposed optimal methods. Results showed that the optimal solutions provided the best performance but raised the problem of difficulty in maintaining linearity with a large displacement. Nevertheless, the performance balance design helped reduce this defect and provided impressive seismic mitigation capacity. Compared with the optimal numerical solution results, the performance balance design demonstrated 2.847% of loss in the maximum structural displacement reduction rate and 3.709% of loss in the root mean square reduction rate during the earthquake-excited period, respectively. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) require to be preheated under cold weather to restore performance, while DC pulse discharging is often considered a promising approach. Applying a larger pulse current can shorten the heating time, but it may lead to battery decay and demand additional cost. To keep the current lower in preheating, it is necessary to explore the effects of pulse current on the cell temperature rise and make full use of the battery's heat-generating potential. This paper experimentally compared the effects of DC pulse, average (AVG) current, root mean square (RMS) current, pulse frequency, and state of charge (SOC) of the LIBs on its temperature rise rate, respectively. It is found that within the frequency of 1 kHz~10 kHz, the heat generation is affected by all factors above, among which the frequency has less impact while AVG current has the highest impact. During DC pulse discharging, it is shown that there is more entropy heat produced than the Joule heat in some SOC ranges. Therefore, entropy heat cannot be overlooked in the heat generation model. Moreover, as the thermal coefficient of entropy varies greatly with the SOC, the battery temperature rise rate will be inconsistent during the DC pulse discharging, which might cause an inconsistent warm-up time. [ABSTRACT FROM AUTHOR]

The modeling of a solar PV system is challenging due to its nonlinear current vs. voltage characteristics. Although various optimization techniques have been applied for the parameter estimation of the solar PV system, there is still a scope to attain the best-optimized results. This paper uses a new meta-heuristic optimization algorithm and a classical technique named Ali Baba and the Forty Thieves (AFT) with Newton Rapson (NR) method to estimate solar PV system parameters. The well-known story of Ali Baba and the Forty Thieves has inspired the AFT. Besides, the inappropriate objective function used in earlier research to extract parameters from solar PV models is recognized. The experimental findings demonstrate that the suggested approach performs better when compared to state-of-the-art algorithms. Between the measured data and the computed data for AFT, the root mean square error values for the five PV models, such as single diode model (SDM), double diode model (DDM), Photowatt-PWP201, STM6-40/36, and STP6-120/36, are respectively 7.72 × 10−04 ± 6.121 × 10−16, 7.412 × 10−04 ± 9.52 × 10−06, 2.052 × 10−03 ± 3.05 × 10−17, 0.001721922 ± 2.19 × 10−17, and 0.014450817 ± 3.42 × 10−16. In terms of accuracy, the obtained results indicate that the proposed AFT algorithm is more efficient than the other optimization techniques available in the literature. The excellent correlation between the estimated parameters from characteristic curves and observed data for SDM, DDM, Photowatt-PWP201, STM6-40/36, and STP6-120/36 demonstrates that the proposed AFT is a potential option among the techniques available in the literature. The Friedman and Wilcoxon tests have been used to assess the statistical validity of the proposed algorithms. [ABSTRACT FROM AUTHOR]

In extra-long road tunnels (>10 km), the interior zone accounts for 95% of the total tunnel length. Driving for an extended period in the interior zone of such a tunnel in a monotonous and dimly lit environment causes heavy visual loads for drivers and undermines the safe operation of tunnels and driving comfort. This study investigated the changing patterns of drivers' visual loads while driving through road tunnels. In a real vehicle experiment, the pupil diameter, fixation duration, electroencephalogram power spectral density, standard deviation of normal to normal, and root mean square of successive differences were used as indicators of drivers' visual loads. By comparing the differences in psychological and physiological parameters in tunnels of four different lengths, this study discovered the changing pattern of drivers' visual loads in the interior zone of extra-long tunnels and merged multi-source information of various indicators based on the entropy evaluation model to obtain comprehensive visual load values for drivers. The experiment revealed that as the tunnel length increased, the changing patterns of the drivers' visual load indicators diverged. In particular, the driver's tension levels began to spike after 180s of driving. The comprehensive visual load values of drivers, combined with the change features of multiple indicators, provide a more accurate and complete assessment of visual loads. The analysis of drivers' visual load features can provide a theoretical basis for measures to optimise the lighting environment of the interior zone of extra-long tunnels over 10 km. [ABSTRACT FROM AUTHOR]

Summary: Increasing the energy efficiency in hybrid energy storage‐based electric vehicles is among the important research areas. Energy sharing in such vehicles is possible with an efficient and optimum energy management system. In this study, a Jaya‐based modular energy management system is proposed to optimize power sharing between battery and ultracapacitor for an electric vehicle. In this system, battery is connected to DC bus directly, and ultracapacitor is connected via a bidirectional DC‐DC converter. This converter provides the power flow between the DC bus and the ultracapacitor as well as perform the proposed energy management system algorithm. The designed modular energy management system has the feature of being easily integrated into a battery‐only electric vehicle, and two‐way power transfer between the battery and the ultracapacitor has been successfully achieved. At the same time, real‐time implementation of Jaya‐based energy management system is experimentally tested for the first time and compared to rule‐based energy management system. The proposed Jaya‐based energy management system reduces the total loss amount by 24.5% and the battery current root mean square value by 28.8% compared to the rule‐based method. The results show that the proposed method can be successfully applied for real‐time energy management system applications. [ABSTRACT FROM AUTHOR]

COVID-19 in Indonesia is considered to be entering the endemic phase, and the population is expected to live side by side with the SARS-CoV 2 viruses and their variants. In this study, procyanidin, oleic acid, methyl linoleic acid, and vitexin, four compounds from binahong leaves-tropical/subtropical plant, were examined for their interactions with the major protease (Mpro) of the SARS-CoV 2 virus. Molecular dynamics simulation shows that procyanidin and vitexin have the best docking scores of −9.132 and −8.433, respectively. Molecular dynamics simulation also shows that procyanidin and vitexin have the best Root Mean Square Displacement (RMSD) and Root Mean Square Fluctuation (RMSF) performance due to dominant hydrogen, hydrophobic, and water bridge interactions. However, further strain energy calculation obtained from ligand torsion analyses, procyanidin and vitexin do not conform as much as quercetin as ligand control even though these two ligands have good performance in terms of interaction with the target protein. [ABSTRACT FROM AUTHOR]

Summary: A detection technique to quantify the degree of bolt looseness in metallic bolted structure using electro‐mechanical impedance signatures is proposed. A bolted joint connection of two steel plates and a stiffener is taken as the specimen to be monitored. Loosening of the bolted joints is considered as the damage present in the structure. At first, the electro‐mechanical responses at two piezoelectric transducer locations are measured experimentally for the undamaged and damaged state of the structure. Damage scenarios with single as well as multiple degrees of bolt looseness are considered. Damage features based on root mean square deviation (RMSD) and correlation coefficient (CC) of conductance with respect to the healthy state conductance are extracted. A single hidden layer backpropagation artificial neural network has been trained for detection of bolt looseness from the damage features. Acceptability of the proposed multiple damage detection technique has been observed through few test cases. [ABSTRACT FROM AUTHOR]

Tooth surface roughness is an important index to evaluate the quality of gear processing, which affects the gear transmission error and tooth friction coefficient and changes the gear dynamics. Based on the fractal theory, the gear error correction model considering time-varying roughness is derived, and the new model of time-varying roughness and gear error is introduced into the Xu model to construct the friction coefficient model accounting for time-varying roughness and gear error, which has great reference value for improving the accuracy of gear error. The research results show that the root mean square value of gear error increases by 45.39% and 101.08% under comparison Ra = 0.8 μm, Ra = 1.6 μm, and R a = 3.2 μm, respectively, and the root mean square value of time-varying friction coefficient increases by 45.74% and 148.18%, respectively, which provides theoretical method support for precision management and quality management of gear processing in machinery enterprises. [ABSTRACT FROM AUTHOR]

Faults in cylindrical roller bearings are one of the main contributors to major faults in rotating machinery. The development of bearing fault diagnosis technologies is key to measuring the performance, status, and risk of failure of rolling-element bearings and has attracted extensive attention from industry and academia. When faults arise, they are often not a single fault but a compound fault, such as the simultaneous failure of the inner and outer races. In this paper, a method for evaluating the size of compound faults on the inner and outer races of cylindrical roller bearings is proposed. The dynamic modeling method developed by Gupta is employed to create a dynamic model for compound faults on the inner and outer rings of rolling bearings that allows the time domain signal of the vibration responses of compound faults on the inner and outer races to be obtained. Adopting an improved continuous harmonic wavelet packet decomposition method for the decomposition and reconstruction of the compound fault signal, we arrive at the corresponding single-point fault signal. The relationship between defect size and key metrics of the vibration, such as root mean square acceleration (RMS), peak, crest factor (CF), kurtosis, and level crossing rate (LCR), is investigated. The results show that there is a strong linear correlation between LCR and defect size, which can be used to evaluate the size of the defect. Experimental data for cylindrical roller bearings with compound faults on the inner and outer races are examined to verify the results. [ABSTRACT FROM AUTHOR]

Summary: The performance and optimal design of the base‐isolated structure supplemented with clutching inerter damper (CID) subjected to seismic loading are investigated. Because of the nonlinear force‐deformation behavior of the CID, the stochastic response of the isolated structure subjected to nonstationary earthquake excitation is obtained using the time‐dependent equivalent linearization technique. To investigate the effects of nonstationary earthquake characteristics, the isolated structure's nonstationary response is compared to the corresponding stationary response. For a given isolated structural system and excitation, there exists an optimum value of the CID inertance at which the root mean square absolute acceleration of the superstructure achieves a minimum value. The effects of key parameters like superstructure flexibility, isolation period, and isolation damping ratio on the CID's optimal inertance are examined. The seismic response of base‐isolated structures is also obtained under real earthquakes using the nonlinear model of the CID. The effects of the CID on the response of isolated structures under real earthquakes were found to be well correlated with those of stochastic analysis. Finally, for the approximate response and initial design of base‐isolated structures, a closed‐form expression for the equivalent damping of the CID is proposed. Using the equivalent inertance and damping of the CID, the bearing displacements and forces of isolated structures with the CID were found to be matching with that obtained by the nonlinear analysis. However, there can be an error in the prediction of structural acceleration and force in the CID by using this equivalent approach. [ABSTRACT FROM AUTHOR]

Great changes have been brought about by the coastal environment when the economy develops rapidly. Coastal environmental monitoring is the basis and technical guarantee for coastal environmental protection supervision and management. It is one of the important tasks to detect and timely discover coastal seawater anomalies. Usually, a single sensor cannot determine whether the coastal environment or ship operation is an anomaly. Recently, an unmanned surface vehicle for coastal environment monitoring was developed, and stacked autoencoders are used for seawater anomaly detection using multisensor data fusion methods. The multisensor data of pH, conductivity, and ammonia nitrogen are employed to judge the anomaly of seawater. The mean, standard deviation, mean square root, and normalized power spectrum features of multisensor data are extracted, and a stacked autoencoder is employed to fuse these features for anomaly detection. The proposed method is feasible and effective for anomaly detection of coastal water quality and ship operation. Compared with other commonly used methods, the proposed method has a higher recall, precision, and F1 score performance. [ABSTRACT FROM AUTHOR]

Alopecia is a health condition in which the hair loses its function in some or all of the body. Alopecia occurs due to various genetic, environmental, and nutritional factors. One of the methods developed to treat alopecia is through inhibition of the enzyme 5-α-reductase, which converts testosterone into its more potent metabolite, dihydrotestosterone (DHT). In ethnomedicine, the leaves of Merremia peltata are used by the people of Sulawesi as a remedy for baldness. Therefore, in this study, an in vivo study was conducted on rabbits to investigate the antialopecia activity of the ethanolic extract of M. peltata leaves. The purified M. peltata leaf extract was fractionated using vacuum liquid chromatography with several solvents to produce fractions F1-F5. Each fraction was then retested in vivo in rabbits, and its content was then analyzed by LC-MS. An in silico study was then carried out using minoxidil as a comparison ligand; 17 compounds derived from M. peltata leaves were identified as antialopecia compounds through prediction of molecular interactions and molecular dynamics simulation and prediction of absorption, distribution, metabolism, excretion, and toxicology (ADME-Tox). The assay results showed that fractions F2 and F3 had a better effect on hair growth compared to the positive control, and the test compound obtained from the LC-MS analysis, bufotalinin, had a strong binding energy to the receptor in the molecular docking interaction study: -5.99 kcal/mol compared to -4.8 kcal/mol for minoxidil. Molecular dynamics simulation analysis with complex stability parameters based on solvent-accessible surface area (SASA), principal component analysis (PCA), root mean square deviation (RMSD), and root mean square fluctuation (RMSF) showed that bufotalinin has good affinity for androgen receptors. ADME-Tox prediction for bufotalinin showed good results for the parameters of skin permeability, absorption, and distribution. Therefore, bufotalinin, a steroid compound, is a potential androgen receptor antagonist and could be useful in the treatment of alopecia. [ABSTRACT FROM AUTHOR]

Neuromuscular electrical stimulation (NMES) has been used to increase muscle strength and physical function. However, NMES induces rapid fatigue, limiting its application. To date, the effect of quadriceps femoris (QF) muscle length by knee and hip joint manipulation on NMES-induced contraction fatigability is not clear. We aimed to quantify the effects of different muscle lengths on NMES-induced contraction fatigability, fatigue index, and electromyographic (EMG) activity for QF muscle. QF maximum evoked contraction (QMEC) was applied in a 26 min protocol (10 s on; 120 s off; 12 contractions) in 20 healthy participants (24.0 ± 4.6 years old), over 4 sessions on different days to test different conditions. The tested conditions were as follows: supine with knee flexion of 60° (SUP60), seated with knee flexion of 60° (SIT60), supine with knee flexion of 20° (SUP20), and seated with knee flexion of 20° (SIT20). Contraction fatigability (torque decline assessed by maximal voluntary contraction [MVC] and during NMES), fatigue index (percentage reduction in MVC), and EMG activity (root mean square [RMS] and median frequency) of the superficial QF' constituents were assessed. After NMES, all positions except SUP20 had an absolute reduction in MVC (p <.001). Fatigue index was greater in SIT20 than in SIT60 (p <.001) and SUP20 (p =.01). There was significant torque reduction across the 12 QMEC in SUP60 and SIT60, up to 10.5% (p <.001 –.005) and 9.49% (p <.001 –.033), respectively. There was no torque reduction during NMES in SUP20 and SIT20. Fatigue was accompanied by an increase in RMS (p =.032) and a decrease in median frequency for SUP60 (p <.001). Median frequency increased only in the SUP20 condition (p =.021). We concluded that QF NMES-induced contraction fatigability is greater when the knee is flexed at 60° compared to 20°. In addition, a supine position promotes earlier fatigue for a 60° knee flexion, but it delays fatigue onset for a 20° knee flexion compared to the seated position. These results provide a rationale for lower limb positioning during NMES, which depends on training objectives, e.g., strengthening or task-specific functionality training. [ABSTRACT FROM AUTHOR]

To obtain a better insight into comprehending the unusual role of ultrasound frequency and enhance the extraction yield of total anthocyanins (TA) from purple sweet potatoes (PSPs), an approach of wide frequency‐based ultrasound‐assisted extraction (WF‐UAE) was applied to evaluate the influence on the extraction of TA under process parameters at different levels, ultrasound frequency (20–84 kHz), ethanol concentration (20–65%), solvent to solid ratio (10–70 ml/g), ultrasound power (50–280 W), temperature (30–70°C), particle size (0.147–0.908 mm), and treatment time. The results showed that ultrasound frequency has more influence on the extraction yield, followed by temperature, treatment time, and other extraction parameters. The maximum yield of 0.567 ± 0.005 mg/g of TA was obtained at optimized parameters, which was significantly higher than Soxhlet extraction where only 0.324 ± 0.002 mg/g was achieved at 98°C for 720 min, as well as higher than ultrasound‐assisted extraction where only 0.465 ± 0.006 mg/g was obtained at 300 W and 20 kHz for 45 min. The extraction kinetics were performed at different levels of process parameters by Peleg's model. Model constants and equilibrium concentration for different process parameters were predicted. Model validation was done by depicting predicted and experimental values from extracted TA. The obtained values of regression coefficient (R2 > 0.972) and root mean square deviation (RMSD < 0.218) indicated that this model has a good agreement with the experimental results. Novelty impact statement: This work is the first to evaluate the effects of ultrasound frequency span a wide range from 20 to 84 kHz and other process parameters on the extraction of TA from PSPs by using an approach of WF‐UAE that was based on a frequency search device with eight extraction tanks controlled by a computer. The application of WF‐UAE technology could not only efficiently extract TA from PSPs, but also be promising for extracting active components from different natural materials in the industry. [ABSTRACT FROM AUTHOR]

The present study evaluated the drying of camu‐camu pomace (reducing waste generation), and a mathematical model is proposed for drying at four different temperatures (60, 80, 100, and 120°C), and 1 m/s airflow. The thin‐layer model that best fitted the experimental data was by Midilli, compared to ten other models. The evaluation method used the coefficient of determination (R2), RMSE (root mean square), and X2 (Chi‐square), wherein the coefficient of determination remained >0.90. The activation energy calculated in the present study was 10.82 kJ mol−1, and effective diffusion coefficient D0 = 0.0012 (m2 s−1). Considering colorimetric parameters and the time of water mass loss, the temperature of 80°C is appropriate to produce a good powder. Thus, the drying of camu‐camu pomace is an alternative to obtain a natural (red‐purple) food dye. Novelty impact statement: To our knowledge, the present study is a pioneer on the grounds that it presents the mathematical modeling data of the residue at high temperature, and also the obtention of camu‐camu powder as natural dye. Considering the perishability of fresh residues, drying is one of the most feasible technological processes for the food industry, also to obtain natural dyes, highlighting to the natural powders. The modeling of drying curves provides an understanding as regards the physical and thermodynamic indices relevant to the heat and mass transfer process of the sample. So, this information is very important and might help to improve the performance of future analyses. [ABSTRACT FROM AUTHOR]

In this study, we evaluate the surface roughness (SR) of three thermally treated nickel-titanium rotary instruments (i.e., TruNatomy [TN], ProTaper Gold [PTG], and EdgeTaper Platinum [ETP]) after impact testing with multiple autoclave sterilization cycles using scanning electron microscopy (SEM). Overall, 60 thermally treated files were sourced (i.e., 20 TN, 20 ETP, and 20 PTG files), and each group was divided into four equal subgroups of five files (n = 5). An unsterilized group was assigned as the pre-autoclaving group (Cycle 0), and the other three groups underwent various autoclave sterilization cycles (Cycles 1, 5, and 10). The roughness average (Ra), root mean square (Rq), and average maximum peak-to-valley height (Rz) values were evaluated using SEM and ImageJ software. The Shapiro–Wilk test, one-way analysis of variance, and post-hoc Tukey test were used to analyze the data. The statistical significance level was set at p < 0.05. Before autoclaving, all instruments showed debris and SR but with no statistically significant differences existing between the groups. SR values decreased after one autoclaving cycle for all instruments. After five autoclave cycles, the Rz value of ETP was statistically higher compared with PTG and TN. After 10 autoclave cycles, the Ra and Rq values of TN were statistically higher compared with ETP and PTG. These results suggest that multiple autoclaving sterilization cycles influence the SR of TN, PTG, and ETP, with ETP showing higher levels of surface irregularities than PTG and TN. [ABSTRACT FROM AUTHOR]

Radar antennas in the open air are affected by dynamic wind loading during azimuthal scanning. In this state, the acquisition and prediction of the aerodynamic load is the focus of the structure design for the antenna. We performed wind tunnel force tests on flat plate antennas with different aspect ratios. The changes in mean, maximum, and root mean square values of the aerodynamic coefficients relative to the antenna aspect ratio and reduced frequency are given for the first time. The effects of the antenna aspect ratio and reduced frequency on aerodynamic characteristics are analyzed. The experimental results indicate that the magnitude of the azimuthal moment is related to the antenna aspect ratio and the reduced frequency. It is worth noting that the antenna aspect ratio has a significant impact on the mean, maximum, and root mean square values of dynamic aerodynamic coefficients. The mean, maximum, and root mean square values of the rolling moment coefficient, azimuth moment coefficient, and pitching moment coefficient monotonously decrease with the increase in aspect ratio. In addition, the influence of reduced frequency on the dynamic aerodynamic coefficient is closely related to the antenna aspect ratio. Under the same antenna aspect ratio, increasing the reduced frequency will increase the mean, maximum, and root mean square values of the aerodynamic coefficient. For flat plate antennas with different aspect ratios, at the condition of increasing the aspect ratios, the mean, maximum, and root mean square values of aerodynamic coefficients do not change significantly with the change of reduced frequency. [ABSTRACT FROM AUTHOR]

Objective. Restoring the correct masticatory function of partially edentulous patient is a challenging task primarily due to the complex tooth morphology between individuals. Although some deep learning-based approaches have been proposed for dental restorations, most of them do not consider the influence of dental biological characteristics for the occlusal surface reconstruction. Description. In this article, we propose a novel dual discriminator adversarial learning network to address these challenges. In particular, this network architecture integrates two models: a dilated convolutional-based generative model and a dual global-local discriminative model. While the generative model adopts dilated convolution layers to generate a feature representation that preserves clear tissue structure, the dual discriminative model makes use of two discriminators to jointly distinguish whether the input is real or fake. While the global discriminator focuses on the missing teeth and adjacent teeth to assess whether it is coherent as a whole, the local discriminator aims only at the defective teeth to ensure the local consistency of the generated dental crown. Results. Experiments on 1000 real-world patient dental samples demonstrate the effectiveness of our method. For quantitative comparison, the image quality metrics are used to measure the similarity of the generated occlusal surface, and the root mean square between the generated result and the target crown calculated by our method is 0.114 mm. In qualitative analysis, the proposed approach can generate more reasonable dental biological morphology. Conclusion. The results demonstrate that our method significantly outperforms the state-of-the-art methods in occlusal surface reconstruction. Importantly, the designed occlusal surface has enough anatomical morphology of natural teeth and superior clinical application value. [ABSTRACT FROM AUTHOR]

In this paper, an athermalizing connection method of the optical components of high-performance optical objectives that enables them to reduce the deterioration of their performance due to temperature instability is proposed. The optical components of the athermalizing connection structure consist of three parts arranged from the outside to the inside. The materials of the intermediate parts are different from those of the external and internal ones. The relationship between the parameters of the athermalizing connection structure is deduced based on the mechanics of materials. The surface errors of optical components at different temperatures are simulated for an exemplary structure. The simulation results show that the root mean square (RMS) of the optical component surface is approximately proportional to the temperature. When the temperature drops by 10 °C, the RMS changes by 0.66 nm as compared to its value measured at 20 °C. The temperature deflection test of the optical components carried out in the temperature range of 20 ± 5 °C provides the RMS values of the optical face of 0.019λ at 15 °C and 0.02λ at 25 °C. The change of RMS obtained in this test amounts to 0.63 nm for a temperature difference of 10 °C, which deviates from the respective simulated value by 4%. The experimental results show that the athermalizing connection method proposed in this paper ensures small deformations of optical components at large temperature changes. Therefore, it meets the requirements for the application of optical components and is suitable for the connection of high-precision components. [ABSTRACT FROM AUTHOR]

The biceps and triceps alternatively act as agonists and antagonists to realize upper limb movement. Pneumatic artificial muscle (PAM), which is inflated and deflated with compressed air instead of water, has similar characteristics to those of human muscle. The challenge is whether an exoskeleton actuated by PAM can help biceps lift the upper limb. Accordingly, the principal aim of this research is to guarantee precise signal collection and control process and adopt the synergy control of PAM and upper limb. In this system, the biceps and triceps provide the main signals in synergy control, electrodes are pasted outside of biceps and triceps to sample their electromyogram signal (EMGs), and the mechanical structure and control system of the pneumatic exoskeleton are proposed. The relationship between duty-ratio-controlled variables and PAM contraction speed is given by experimental analysis, and the maximum duty ratio of controlled variables of input is set to 80. The feature analysis of EMGs can be various including envelope, moving average, and moving root mean square (RMS). The envelope is taken to extract muscle contraction information through upper limb muscles in a static contraction experiment. Then, the processes of biceps and triceps EMGs feature changes including rapid swing, slow swing, and discontinuous swing under various loads are analyzed during upper limb muscle dynamic contraction. The duty-ratio-controlled variables can be divided into five levels, which correspond to exertion rating from powerless to very strong in two EMG characters. These can be reflected in a scatter diagram of duty-ratio-controlled variables and average EMG characters. A nonlinear relationship can be transferred into the continuous system by the polynomial interpolation method, solving the problem of saturation. The net duty-ratio-controlled variables are adopted to control the on-off state and pulse-width modulation (PWM) duty ratio of the high-speed on-off valve. The forearm lifting up movement is unpowered and powered with various load EMGs, and elbow discontinuous swing angle overshoot is performed to analyze the coordination effect in a synergy control experiment. [ABSTRACT FROM AUTHOR]

It is documented that regular exercise is beneficial for improving the antioxidant system, metabolic system, cardiac autonomic function, and blood pressure in those with hypertension. In this regard, low-intensity exercise is recommended for older adults, particularly those with chronic diseases. This study aimed to compare the effects of long-term regular continuous walking with intermittent walking on oxidative stress, metabolic profile, heart rate variability, and blood pressure in older adults with hypertension. Forty-three participants with hypertension aged 60-80 years were randomly divided into the continuous or intermittent walking (CON or INT) groups. Participants in the CON group walked for 30 min, 3 days/week for 12 weeks. Participants in the INT group split 30 min walking into 3 identical sessions punctuated by a 1 min rest after each session, 3 days/week for 12 weeks. Antioxidant and oxidative stress markers, metabolic markers, heart rate variability, and blood pressure were evaluated before and after the exercise program. Glutathione (GSH), GSH to GSH disulfide (GSSG) ratio, and total GSH increased significantly, and GSSG and malondialdehyde decreased significantly in both groups (p < 0.05) without significant differences between groups. Triglycerides, ratio of total cholesterol to high-density lipoprotein cholesterol, and atherosclerogenic index were significantly lower in the CON group than those in the INT group (p < 0.05). The standard deviation of the NN intervals and root mean square of the successive differences were significantly higher, and low-frequency power was significantly lower in the INT group than that in the CON group (p < 0.05). No significant changes in blood pressure were noted in both groups, and nor were there any significant differences between groups. Long-term regular continuous and intermittent walking may comparably increase antioxidants, reduce oxidative stress, and be beneficial for improving important blood pressure-related outcomes, including metabolic profile or cardiac autonomic function in older adults with hypertension. [ABSTRACT FROM AUTHOR]

In the series arc fault detection of a low-voltage distribution network, the features of the fault current signal are easily submerged and arc fault features are difficult to be represented, which greatly increases the difficulty of fault arc detection based on current signals. To solve these problems, a series arc fault detection method combining CEEMDAN decomposition and sensitive IMF selection is proposed. In this paper, the CEEMDAN algorithm is first applied to complete decomposition of the arc current in series faults. Then, 12 feature indicators of the arc current are defined and the frequency band division of the IMF component is realized according to the kurtosis index and energy feature which are more sensitive. The time window-based feature calculation method is proposed to obtain the local features of the time scale of each high-frequency IMF component. Accurate selection of sensitive IMF components is realized by comparing feature indexes such as the variance and root mean square value. Finally, for the current feature set, the second dimension reduction is realized by the subspace transformation algorithm and the series arc fault detection is realized based on the SVM. The actual experiments show that the optimal detection accuracy of the proposed method is 91.67% and the average accuracy of 10 crossvalidation experiments is 88.33%. It shows that the proposed sensitive IMF selection method can effectively capture the fault component signals in the current and the proposed fault feature description method has good representation and discrimination ability. [ABSTRACT FROM AUTHOR]

Background. Contralaterally controlled neuromuscular electrical stimulation (CCNMES) is a novel electrical stimulation treatment for stroke; however, reports on the efficacy of CCNMES on lower extremity function after stroke are scarce. Objective. To compare the effects of CCNMES versus NMES on lower extremity function and activities of daily living (ADL) in subacute stroke patients. Methods. Forty-four patients with a history of subacute stroke were randomly assigned to a CCNMES group and a NMES group (n = 22 per group). Twenty-one patients in each group completed the study per protocol, with one subject lost in follow-up in each group. The CCNMES group received CCNMES to the tibialis anterior (TA) and the peroneus longus and brevis muscles to induce ankle dorsiflexion motion, whereas the NMES group received NMES. The stimulus current was a biphasic waveform with a pulse duration of 200 μs and a frequency of 60 Hz. Patients in both groups underwent five 15 min sessions of electrical stimulation per week for three weeks. Indicators of motor function and ADL were measured pre- and posttreatment, including the Fugl–Meyer assessment of the lower extremity (FMA-LE) and modified Barthel index (MBI). Surface electromyography (sEMG) assessments included average electromyography (aEMG), integrated electromyography (iEMG), and root mean square (RMS) of the paretic TA muscle. Results. Values for the FMA-LE, MBI, aEMG, iEMG, and RMS of the affected TA muscle were significantly increased in both groups after treatment (p < 0.01). Patients in the CCNMES group showed significant improvements in all the measurements compared with the NMES group after treatment. Within-group differences in all post- and pretreatment indicators were significantly greater in the CCNMES group than in the NMES group (p < 0.05). Conclusion. CCNMES improved motor function and ADL ability to a greater extent than the conventional NMES in subacute stroke patients. [ABSTRACT FROM AUTHOR]

The influences of transmission housing elastic deformations on the vibration gear shafting characteristics are studied. The vibration model of the vehicle transmission system in consideration of the dynamics coupling of the housing and the gear shafting is constructed. Aiming at a vehicle transmission, the mathematical model of the bending and torsional gear shafting vibrations is established based on the lumped mass method. Following the elastic treatment of the box, a comprehensive stiffness model at the bearing considering the housing deformation is proposed to achieve the dynamic coupling between the box and the gear shafting system. Furthermore, the gear shafting vibration characteristics considering housing deformations are obtained by integrating multisource dynamic excitation, which is solved using an iterative method. The results are verified through a bench test. And, it shows that the elastic deformation of the housing aggravates the gear shafting vibration (bending and torsional coupled vibration). The peak frequency mostly remains the same. The maximum speed changes amplitude and associated root mean square value (calculated at the gear position) increase by 55.5% and 59.6%, respectively. Next, the maximum bearing support force and its root mean square value are increased by 63.7% and 97.6%, respectively. Finally, the largest increase in maximum vibration acceleration at the measuring point and the simulated root mean square value are 90% and 63.1%, respectively. It is concluded that the research results provide a theoretical basis for the study of transmission dynamic reliability. [ABSTRACT FROM AUTHOR]

The building integrated semitransparent photovoltaic (BISTPV) system is an emerging technology which replaces the conventional building material envelopes and roof. The performance prediction of the BISTPV system places a vital role in the reduction of the energy consumption in the building. In this work, the artificial neural network (ANN) is used to predict the performance of this system by optimizing the important parameter of the feature selection. The Elman neural network (EN) algorithm, feed forward neural network (FN), and generalized regression neural network model (GRN) are investigated in this study. The performance metrics of the errors are analysed such as the root mean square error (RMSE), mean absolute percentage error (MAPE), and mean square root (MSE). According to the findings, the model behaves consistently at the specified time and place in the experiment. Forecasters utilizing neural network models will have better accuracy if they use techniques like EN, FFN, and GRN having the RMSE of 0.25, 0.37, and 0.45, respectively. [ABSTRACT FROM AUTHOR]

The study of typhoon wind profiles, especially offshore typhoon wind profiles, has been constrained by the scarcity of observational data. In this study, the Doppler wind lidar was used to observe the offshore wind profiles during Super Typhoon Mangkhut and onshore wind profiles during Super Typhoon Lekima. Four wind profile models, including the power law, logarithmic law, Deaves–Harris (D-H), and Gryning, were selected in the height range of 0–300 m to fit the wind profile. The variations in the power exponent with the mean wind speed and roughness length were also analyzed. The results showed that the wind profiles fitted by the four models were generally in good agreement with the observed wind profiles with correlation coefficients greater than 0.98 and root mean square deviations less than 0.5 m s−1. For the offshore case, the fitting degree of all wind profile models improved with increasing mean wind speed. Specifically, the D-H model had the highest fitting degree when the horizontal mean wind speed at 40 m was in the range of 8–25 m s−1, while the log-law model had the highest fitting degree when the wind speed exceeded 30 m s−1. For the onshore case, the fitting degree of the four wind profile models deteriorated with increasing mean wind speed, and the log-law model had the highest fitting degree in all wind speed intervals from 8 to 30 m s−1. For both offshore and onshore cases, the power exponent was less affected by mean wind speed and increased with increasing roughness length, and the logarithmic empirical model proposed in this study could well characterize the relationship between the power exponent and roughness length. [ABSTRACT FROM AUTHOR]

The swing behaviour of tower cranes under compound working conditions is closely related to construction safety and structural health. This paper presents dynamic models and simulated them for parameter analysis to understand tower cranes' dynamic characteristics and vibration features under compound working conditions. The parameters contain payload mass, rope length, lifting acceleration, slewing acceleration, luffing acceleration, and initial angle. For the lifting-luffing coupling motion (LLCM) and lifting-slewing coupling motion (LSCM) of the tower crane, the D'Alembert principle provides a theoretical basis for the derivation of system dynamics equations. The spatial swing angle description of the crane payload includes the time-domain response and frequency-domain response, which uses a dynamic model. The result shows that the mass has little effect on the spatial swing angle. The value of the lifting acceleration is stable at 0.004 m/s2 to 0.01 m/s2. Peak value (PV), root mean square value (RMS), root mean square frequency (RMSF), and frequency standard deviation (RVF) present the best sensitivity to changes in the spatial swing angle response. When PV of angles θ and β increases by tens of thousands of times in the LLCM, PV can reflect the phenomenon of angle divergence. The skewness value (SV) increases by 3422% at the severe swing angle performance in the LSCM. The swing angle regularity with the compound working conditions can provide theoretical guidance for eliminating structural vibration. [ABSTRACT FROM AUTHOR]

To study the effects of aerodynamic loads on the aerodynamic characteristics of stationary and azimuthally rotating antennas, wind tunnel force tests are conducted using solid and porous plate antennas. The variation of aerodynamic coefficient with azimuth angle is obtained when the antenna is stationary and azimuthal rotation, and the results are compared with those from numerical simulations. The variation in the aerodynamic coefficients with respect to the azimuth angle is found to be sinusoidal for both the solid and porous plate antennas rotating in azimuth. Compared with the antenna stationary, quantitative analysis indicates that the rotational motion increases the maximum value and root mean square of the aerodynamic coefficient. For solid plate antenna, |Cx|_max, |Cmy|_max, and |Cmz|_max increase by 41.6%, 15.0%, and 47.3%, respectively; Cx_rms, Cmy_rms, and Cmz_rms increase by 19.0%, 20.0%, and 19.1%, respectively. For porous plate antenna, |Cx|_max, |Cmy|_max, and |Cmz|_max increase by 30.6%, 71.4%, and 40.9%, respectively; Cx_rms, Cmy_rms, and Cmz_rms increase by 22.9%, 50%, and 20%, respectively. The wind tunnel tests verify the feasibility of using numerical simulations to obtain the flow field results. By analyzing the surface pressure coefficient and vortex core track distribution, the effects of azimuthal rotation on the aerodynamic characteristics of the antenna are further clarified. [ABSTRACT FROM AUTHOR]

This is the first time that the landscape footpath is realized on the suspension monorail system. To study the comfort of pedestrians on the landscape footpath when the vehicle passes, the dynamic responses of the track beam and the landscape footpath at different speeds were analyzed using the established vehicle-bridge dynamic analysis model. To evaluate the comfort of pedestrians on the landscape footpath, two indexes, Root Mean Square (RMS) value of acceleration (ISO 10137) and peak value of acceleration (EN 03), were adopted. Results show that the displacement and acceleration responses of landscape footpath and track beam are obviously different. Vertical displacement of the track beam is much larger than that of the landscape footpath due to the eccentric load of vehicles. Due to the displacement and rotation of the structural components which support the landscape footpath, the lateral response transferred to the landscape footpath would be slightly weakened. Maximum RMS values of the lateral and vertical acceleration of landscape footpath are 0.162 m/s2 and 0.169 m/s2, respectively, which meet the requirements of ISO 10137. Peak lateral acceleration is 0.546 m/s2, which reaches CL3 standard, and the peak vertical acceleration is 0.548 m/s2, which reaches CL2 standard. Lateral comfort is slightly worse than vertical comfort. [ABSTRACT FROM AUTHOR]

This paper investigated the friction-induced vibration (FIV) behavior under the running-in process with oil lubrication. The FIV signal with periodic characteristics under lubrication was identified with the help of the squeal signal induced in an oil-free wear experiment and then extracted by the harmonic wavelet packet transform (HWPT). The variation of the FIV signal from running-in wear stage to steady wear stage was studied by its root mean square (RMS) values. The result indicates that the time-frequency characteristics of the FIV signals evolve with the wear process and can reflect the wear stages of the friction pairs. The RMS evolution of the FIV signal is in the same trend to the composite surface roughness and demonstrates that the friction pair goes through the running-in wear stage and the steady wear stage. Therefore, the FIV signal with periodic characteristics can describe the evolution of the running-in process and distinguish the running-in wear stage and the stable wear stage of the friction pair. [ABSTRACT FROM AUTHOR]

This study draws attention towards the application of identification nanoparticle (NPs) sensor based on back propagation (BP) neural network optimized by genetic algorithm (GA) in the early diagnosis of cancer cells. In this study, the traditional and optimized BP neural networks are compared in terms of error between the actual value and the predictive value, and they are further applied to the NP sensor for early diagnosis of cancer cells. The results show that the root mean square (RMS) and mean absolute error (MAE) of the optimized BP neural network are comparatively much smaller than the traditional ones. The particle size of silicon-coated fluorescent NPs is about 105 nm, and the relative fluorescence intensity of silicon-coated fluorescent NPs decreases slightly, maintaining the accuracy value above 80%. In the fluorescence imaging, it is found that there is obvious green fluorescence on the surface of the cancer cells, and the cancer cells still emit bright green fluorescence under the dark-field conditions. In this study, a phenolic resin polymer CMK-2 with a large surface area is successfully combined with Au. NPs with good dielectric property and bioaffinity are selectively bonded to the modified electrode through a sulfur-gold bond to prepare NP sensor. The sensor shows good stability, selectivity, and anti-interference property, providing a new method for the detection of early cancer cells. [ABSTRACT FROM AUTHOR]

Summary: This article discloses a clamping sequence duty ratio control (CSEQ‐DRC) for photovoltaic (PV)‐fed indirect vector control (IVC) of induction motor (IM) drive. Solar PV is one of the prominent renewable green energy resources and made a pollution‐free power generation without carbon emission. The PV‐fed IM drives are used in many applications such as water pumping, electric vehicle, industrial applications, etc. However, solar panels suffer from low efficiency. Moreover, it can be overcome using the maximum power point tracking (MPPT) technique, and the MPPT is achieved using incremental conductance (Inc‐Cond). The speed of IM can be controlled using IVC with the help of an inverter. The inverter is inherently controlled based on the pulse width modulation (PWM) techniques for reducing the voltage or current harmonics. Here, the proposed CSEQ‐DRC involves two switching sequences such as CSEQ0 and CSEQ1, in every sector region. For every sector region, the appropriate sequence can be operated/selected in the less area of root mean square (RMS) of the stator flux ripples (SFRs) to reduce the line voltage/current profiles of the IM. Consequently, the torque ripples and speed fluctuations are further reduced significantly with the proposed CSEQ‐DRC than the conventional space vector duty ratio control (CSVDRC). In real‐time applications of PV‐fed IVC IM, the interface of the DSPACE DS‐1104 controller is used here to implement for both the proposed CSEQ‐DRC and CSVDRC techniques. Also, the overall performance of the IM drive is improved with the proposed technique as compared to the CSVDRC at different operating conditions. [ABSTRACT FROM AUTHOR]

Summary: Tensegrity domes are reticulated prestressed structures composed of bars in compression and cables in tension. These structures are flexible lightweight systems with low structural damping, and thus, they are sensitive to vibrations induced by strong wind and earthquakes. The present work deals with the robust multimodal control of a large‐scale tensegrity dome of Geiger's type. Assuming random excitations and linear behavior of the structure around an equilibrium prestressed configuration, the control is achieved in the low‐frequency range using multiple tuned mass dampers (MTMDs). The optimal MTMD parameters, ensuring optimal performances, are obtained using a root mean square displacement (RMSD)‐based approach. The optimization strategy is firstly applied, in a deterministic context where the structural parameters uncertainties are not included, to control the fundamental resonant frequency of the dome structure and then extended to perform multimodal control using multiobjective optimization. In addition, in real‐life situations, it's very hard to describe actual engineering structures in precise model yielding to unavoidable internal and external uncertainties. To deal with these uncertainties, it has been shown that the proposed multimodal control is also able to carry out robust control in presence of structural uncertainties. The proposed optimization strategy applied to the dome structure is compared to other optimization strategies, from the open literature. The obtained results showed the efficiency of the proposed methodology of the passive control in both contexts, that is, the deterministic and the non‐deterministic where uncertainties are considered. [ABSTRACT FROM AUTHOR]

In order to improve the ride comfort and handling stability of the vehicle and realize the recovery of vibration energy, an electromagnetic linear hybrid suspension actuator composed of linear motor and solenoid valve shock absorber is proposed. At the same time, a fault diagnosis and fault-tolerant control strategy is designed to solve the system instability caused by the fault of electromagnetic hybrid active suspension. The 1/4 vehicle two-degree-of freedom suspension model, the linear motor mathematical model, and the solenoid valve shock absorber test model are established. In this paper, the fuzzy sliding mode controller is used as the controller and the unknown input observer is used to estimate the state of the suspension. According to the residual obtained from the unknown input observer and compared with the residual threshold, the suspension fault is determined. In the case of fault, the fuzzy sliding mode controller is used to compensate the force and realize the suspension fault-tolerant control. The performance of the suspension is simulated on random road and bumped road, respectively. The simulation results show that the fault-tolerant control effect of the three performance indexes of the suspension is good, and the ride comfort and safety of the suspension are improved. Finally, the bench test is carried out, and the test results show that in the fault-tolerant control state, the root mean square value of the sprung mass acceleration is reduced by 31.69% compared with the fault state and the dynamic performance of the suspension is improved. [ABSTRACT FROM AUTHOR]

In order to meet the higher data transmission rate requirements of subway communication services, the millimeter wave (mmWave) broadband communication is considered as a potential solution in 5G technology. Based on the channel measurement data in subway tunnels, this paper uses ray-tracing (RT) simulation to predict the propagation characteristics of the 28 GHz millimeter wave frequency band in different tunnel scenarios. A large number of simulations based on ray-tracing software have been carried out for tunnel models with different bending radiuses and different slopes, and we further compared the simulation results with the real time measurement data of various subway tunnels. The large-scale and small-scale propagation characteristics of the channel, such as path loss (PL), root mean square delay spread (RMS-DS), and angle spread (AS), for different tunnel scenarios are analyzed, and it was found that the tunnel with a greater slope causes larger path loss and root mean square delay spread. Furthermore, in the curved tunnel, the angle spread of the azimuth angle is larger than that in a straight tunnel. The proposed results can provide a reference for the design of future 5G communication systems in subway tunnels. [ABSTRACT FROM AUTHOR]

In this paper, we have performed qualitative and quantitative analysis of LuMnO3 thin films surfaces, deposited by spin coating over Pt(111)/TiO2/SiO2/Si substrates, to evaluate their spatial patterns as a function of the film's sintering temperature. Atomic force microscopy was employed to obtain topographic maps that were extensively analyzed via image processing techniques and mathematical tools. 3D (three-dimensional) topographical images revealed that films sintered at 650°C and 750°C presented the formation of smoother surfaces, while the film sintered at 850°C displayed a rougher surface with a root mean square roughness of ∼2.5 nm. On the other direction, the height distribution of the surface for all films has similar asymmetries and shape, although the film sintered using the highest temperature showed the lower density of rough peaks and a sharper peak shape. The advanced fractal parameters revealed that the film sintered at 850°C is dominated by low spatial frequencies, showing less spatial complexity, higher microtexture homogeneity, and uniform height distribution. These results suggest that the combination of stereometric and fractal parameters can be especially useful for identification of unique topographic spatial patterns in LuMnO3 thin films, helping in their implementation in technological applications, such as photovoltaic solar cells and information magnetic date storage and spintronic devices. [ABSTRACT FROM AUTHOR]

In order to improve the surveillance effect of the aviation target surveillance radar, this paper improves the traditional filtering algorithm and builds the channel optimization system of the ADS-B aviation target surveillance radar based on the improved filtering algorithm. Moreover, this paper uses algorithm improvement to ensure the positive definite or semipositive definiteness of the state covariance and uses the root mean square volume Kalman filter to avoid the filter divergence or tracking interruption caused by the nonpositive definiteness of the matrix; the filtering principle of the interactive multimodel is to use multiple filters for parallel processing and achieve the adaptive adjustment algorithm residual error by adjusting the one-step prediction covariance in the adjustment algorithm. In addition, this paper combines the actual needs to construct a system functional structure to optimize the channel of the ADS-B aviation target surveillance radar and uses software engineering methods to model and analyze the requirements. Finally, this paper designs experiments to verify system performance. The research results show that the performance of the system constructed in this paper meets actual needs. [ABSTRACT FROM AUTHOR]

The hydrodynamic theoretical lubrication model of the friction pair between the rotary shaft and the lip seal under the state of full film lubrication was established in this paper. The Reynolds equation was solved by using the finite difference method, and the influence of the viscosity-temperature characteristics of the lubricant was taken into account in the solution process. The distribution of the film thickness and the hydrodynamic pressure in the sealing area was obtained. At the same time, the bench test was carried out and the correctness of the model was verified by comparing the simulation results and test results of reverse pumping rate and friction torque under different rotational speed of the shaft. The microasperity of the lip surface is a necessary condition for achieving the sealing effect. Therefore, the influences of the contact load of the seal and the root mean square deviation of the lip surface on the sealing performance and frictional property were analyzed by using the theoretical model. The analysis results show that the sealing performance and frictional property can be changed by changing the contact load and surface roughness of the lip, but a single increase in the influence of a certain factor cannot achieve good results, and comprehensive consideration is required in product design. [ABSTRACT FROM AUTHOR]

An uneven-span modified greenhouse dryer was constructed and tested in no-load conditions under natural convection mode under the weather conditions of Marrakech, Morocco, for two distinct days. Moreover, a CFD evaluation of the uneven-span greenhouse dryer was performed as tool to visualize the air temperature distribution inside the dryer. For validating the CFD model, the temperature variations along the hours of the day were compared to the experimental results. A good agreement is obtained between the computed and measured inside air temperature with a difference not exceeding 8.46°C, with a correlation coefficient (r) and root mean square percentage deviations (e) 0.94 and 8.17, respectively. Furthermore, the maximum inside air temperature was measured to be 56°C and 52°C while the minimum inside relative humidity was measured to be 17% and 12%, for day-1 and day-2, respectively. The benefice of using asphalt as a floor covering material was revealed as an efficient way to heat the inside air at low solar radiations. The performances of the dryer were evaluated by the percentage of net heat gain variation as a way to validate the effectiveness of the dryer. This latter is found to be equal to 46% and 48% for the two days, respectively. [ABSTRACT FROM AUTHOR]

The aerodynamic characteristics of radar antennas should be considered in computing their wind resistance and designing pedestal servo systems. In this paper, the aerodynamic characteristics of a flat plate antenna with azimuthal rotation are explored using a wind tunnel, and the effects of the antenna elevation angle and reduced frequency on the aerodynamic coefficients are analyzed. The corresponding results of numerical simulation are given to compare with the experimental results. The variation of aerodynamic coefficients with respect to the azimuth angle is found to depend on the reduced frequency and the antenna elevation angle. When the increase in antenna elevation angle is slight, the mean and root mean square values of the aerodynamic coefficients are not monotonic with respect to increases in elevation angle and may increase at individual elevation angles. When the elevation angle increases significantly, the mean, maximum, and root mean square values of the aerodynamic coefficients all significantly decrease. The simulation results are in good agreement with the experimental results, which verify the feasibility of using unsteady numerical simulations to obtain the flow field structure when the antenna is rotating. This approach allows the influence mechanism of the elevation angle change on the aerodynamic characteristics of the rotating antenna to be identified. [ABSTRACT FROM AUTHOR]