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Baicalein (5,6,7-trihydroxyflavone) is a traditional Chinese medicine with multiple pharmacological and biological activities including anti-inflammatory and anti-fibrotic effects. However, whether baicalein has a therapeutic impact on peritoneal fibrosis has not been reported yet. In the present study, network pharmacology and molecular docking approaches were performed to evaluate the role and the potential mechanisms of baicalein in attenuating peritoneal dialysis-associated peritoneal fibrosis. The results were validated in both animal models and the cultured human mesothelial cell line. Nine intersection genes among baicalein targets and the human peritoneum RNA-seq dataset including four encapsulating peritoneal sclerosis samples and four controls were predicted by network analysis. Among them, MMP2, BAX, ADORA3, HIF1A, PIM1, CA12, and ALOX5 exhibited higher expression in the peritoneum with encapsulating peritoneal sclerosis compared with those in the control, which might be crucial targets of baicalein against peritoneal fibrosis. Furthermore, KEGG and GO enrichment analyses suggested that baicalein played an anti-peritoneal fibrosis role through the regulating cell proliferation, inflammatory response, and AGE-RAGE signaling pathway. Moreover, molecular docking analysis revealed a strong potential binding between baicalein and MMP2, which was consistent with the predictive results. Importantly, using a mouse model of peritoneal fibrosis by intraperitoneally injecting 4.25% glucose dialysate, we found that baicalein treatment significantly attenuated peritoneal fibrosis, as evident by decreased collagen deposition, protein expression of α-SMA and fibronectin, and peritoneal thickness, at least, by reducing the expression of MMP2, suggesting that baicalein may have therapeutic potential in suppressing peritoneal dialysis-related fibrosis.

In this work, effect of martensite pre-quenching on the subsequent bainite transformation kinetics of GCr15 bearing steel has been investigated by means of dilatometry. The results show that the pre-quenched martensite is significantly accelerate nucleation of subsequent bainite transformation in comparison with direct bainite austempering. Meanwhile, specimen of martensite pre-quenching at 200 °C has the shortest incubation period of bainite transformation at 240 °C. Moreover, the transformation rate of bainite transformation after martensite pre-quenching is faster than direct bainite austempering in the initial growth stage, and decrease with the decreasing of martensite pre-quenching temperature. Compared with the conventional quenched and tempered (QT) specimen, the tensile strength is slightly decrease from 2170 MPa to 2143 MPa, but the impact toughness is obviously increase from 43 J to 71 J in specimen heat-treated by martensite pre-quenching at 200 °C and subsequent bainite transformation at 240 °C. In addition, the mechanical stability of retained austenite in all martensite pre-quenching specimens are higher than that of QT specimen.

In this work, the carbide dissolution and precipitation of M50 bearing steel were investigated as a function of cold rolling reduction. It is observed that the prior cold rolling not only enhances the dissolution of primary carbides, but also contributes to the carbide precipitation. Additionally, the influence of prior cold rolling on the dry wear behaviors of M50 bearing steel was studied, finding that the friction coefficient as well as wear rate decreases with the increasing cold rolling reduction. This result could be attributed to the formation of stable self-lubricating film within the subsurface layer for the specimens with cold rolling.

A steering wheel may not be able to return to the center position due to friction torque in its mechanism. Thus, in this study, a return controller is developed to improve the returnability of an electric power steering vehicle without an angle sensor. The aligning moment is well estimated on the basis of a Kalman filter estimator. A trigger rule is also proposed to switch between assist and return controls. Finally, the compensation current for the return control is regulated in accordance with the aligning moment and vehicle speeds. Simulation and real vehicle results show that the proposed control system can significantly improve the returnability of the steering system.

Repetitive control has been employed to grid current control owing to the high steady-state accuracy and good harmonics suppression ability. However, in a distributed generation system, the grid frequency will change in a certain range, which will cause deterioration of system stability. Therefore, a proportional integral multi resonance (PIMR) control scheme based on FIR filter is proposed to restrain odd harmonic of grid-connected inverter. While the frequency is variable, FIR filter coefficients can be adjusted online that the resonant frequency of PIMR can approximate to real grid frequency. This scheme can reduce the influence of grid frequency fluctuations on the system and suppress the odd harmonics excellently. Finally, simulation verified the effectiveness of the proposed control strategy.

With the large number of volatile renewable energy sources such as wind power being connected to the grid, the traditional power operation scheduling method has been unable to meet the consumption demand of renewable energy. Firstly the paper comprehensively considers the traditional nuclear power operation mode and wind power output characteristics, adopts the fixed peak depth, uses the Pearson correlation coefficient to match the nuclear power and wind power output during the pre-dispatch period and determine the optimal nuclear power operation mode. Secondly, on the basis of not changing the base load characteristics of nuclear power and considering its safety and economy, a nuclear power peak shaving operation model suitable for coordinating wind power consumption has been established, and the particle swarm algorithm is used to realize the coordinated and optimized dispatch of multi-source. The paper selects data from northern China to verify that the proposed optimized operation method can increase the proportion of wind power consumption, improve economy and ease the pressure of peak shaving.

This article firstly analyzes the unloading strategies of the wind turbine in different wind speeds, and designs a strategy to combine the over speed unloading and the pitch unloading. The droop characteristic is used to convert the active power increment required by the primary frequency regulation into the change of the unloading level, and the inertial response and primary frequency regulation are realized through changing power tracking curves. Finally, a simulation analysis of the unloading frequency regulating control under multiple wind speeds is carried out by using Matlab/Simulink software. The results show that the proposed strategy can achieve the expected target of the primary frequency regulation, eliminate the mutual influence between the additional droop control and the power tracking control, coordinate the inertial control and the primary frequency regulation control, and be restored to the initial state after the deviation of system frequency is eliminated.

Significant differences exist in terms of use and demand of urban public space in different districts and communities. In this study, PSPL survey was made in about one year to investigate the type and occurring time of outdoor activities and the visitors' demand difference of Round-City-Park in Xi'an, China. The survey method for collecting data included spatial classification, photographic recording, field observation, questionnaires and interviews. Then a new method of Virtual Typical Day (VTD) was put forward to analyze usage pattern of public space in the daily life. According to our results, laying out more public spaces close to residential area can make a more vigorous city. And the results also reveal that there exist some problems of uneven usage periods in different spaces, various space requirement from different age groups, insufficient support of space and facilities and so on. Based on the survey, an optimizing strategy of adaptive design is proposed such as setting mobile “stage” and providing flexible “props” according to the changing demands. The proposed design approach can encourage people to participate in outdoor activities, improve usage frequency of public spaces, and stimulate vitality of the city. This may also apply to other Chinese cities.

This paper proposes a nonlinear model predictive control (NMPC) method for active front steering (AFS) system to improve vehicle handling and stability performance at handling limits. Nonlinear vehicle and tire models are adopted in this proposed NMPC controller to describe the nonlinear dynamics of vehicle and tire. In addition, the nonlinear optimal problem is solved by nonlinear solver in MATLAB optimization toolbox. Finally, this study explores the effectiveness of the NMPC system through sine and double lane change maneuver. Results corroborate that the proposed NMPC system can enhance the yaw stability at the handling limits.

A high standard of tea quality control is extremely important for the sake of the health protection of consumers. With the fast-growing of Deep Learning, the intelligent and labor-free authentication of the tea quality, becomes a substantially demanded yet unexplored area, with two key problems yet to be solved: (1) sampling of tea data, with a fast and environmentally friendly approach, (2) distinguishment of tea, in terms of building an accurate tea classifier. To solve the above two problems, NIR spectroscopy is used to collect the tea NIR data in a fast, non-invasive, and environmentally friendly manner. And this paper proposed a series of brand new convolutional neural networks(CNNs) for NIR-based tea data, called TeaNet, TeaResnet, and TeaMobilenet. Due to the success of the different network architectures in the classification task, this paper applies the basic convolution block, the residual block, and the inverted residual block into the network architecture designs, corresponding to TeaNet, TeaResnet, and TeaMobilenet. To serve as the input of networks, NIR data is transformed into a pseudo image and then the model exploits the information in NIR data to make a classification. In an extensive experimental study, we compare TeaNet, TeaResnet, and TeaMobilenet with the traditional machine learning algorithms like Support Vector Machine (SVM) and Random Forest. The experimental results indicate that TeaNet, TeaResnet, and TeaMobilenet could break through the accuracy bottleneck of traditional machine learning algorithms and reach up to a 100% accuracy rate. At the same time, the comparative experiments of the four preprocessing methods-Mean Centering (MC), Savitzky-Golay smoothing (SG), Standard Normal Variate (SNV), and Normalization(Norm) indicate that there is a positive correlation between standard deviation and classification performance. SNV is the best preprocessing method for tea near-infrared spectroscopy data with the greatest standard deviation.

This paper presents a nonlinear model predictive path tracking control method based on tire adhesion margin. The proposed method considers a vehicle’s tire adhesion margin and introduces it into an objective function, which can effectively improve the safety of automobiles. Moreover, autonomous vehicles would have increased more maneuverability to enable them to deal with some emergencies when their tire adhesion margin is large. To confirm the feasibility and effectiveness of the controller, Simulation experiments are performed on MATLAB and CarSim/Simulink under diverse scenarios.

In the space optical communication system, the link power loss is large, and the unequal error protection (UEP) scheme can effectively protect more important data in the transmission process and save transmission power. However, the performance of existing unequal error protection LDPC codes used directly in space optical communication systems is not ideal. In this paper, a design scheme of LDPC codes with multilevel unequal error protection performance is proposed for pulse position modulation (PPM) and Low-density parity-check (LDPC) codes iterative demodulation system. The scheme is aimed at maximizing the average variable node degree of each protection level to improve the unequal error protection characteristics of LDPC codes while combining the improved external information in the BICM-ID system extrinsic information transfer(EXIT) method to analyze the convergence threshold of degree distribution and optimize the degree distribution of UEP-LDPC code by iterative linear programming to obtain the minimum threshold and satisfy the unequal error protection characteristics. The simulation results show that the UEP-LDPC code constructed in this paper has improved performance compared with the existing UEP-LDPC code.

In this work, the ultrafine spheroidized carbides were obtained by combining warm deformation with the divorced eutectoid transformation (DET) in GCr15 bearing steel. The results show that the temperature range of DET is approximately 730 °C to 700 °C at a cooling rate of 0.05 °C s−1. It is also found that excellent spheroidized microstructure can be obtained and less deformation resistance can be generated when the deformation is carried out at 720 °C with a strain rate of 0.5 s−1. This result could be ascribed to the fact that deformation provides the driving force for transformation, dynamic recrystallization (DRX) and reduced dislocation density through the coordination of warm deformation and DET. This suggests that the deformation at the initial temperature is more favorable to the spheroidization than that at the intermediate temperature of DET. In addition, it is also proved that the warm rolling forming in the actual production line can shorten the spheroidization time from at least 10 h to 2 h and obtain ultrafine spheroidized carbides with the roundness close to 1. This research may provide a novel pathway to obtain good spheroidization effect with less energy conservation.

Aiming at the state estimation problem of a class of nonlinear systems, a method of Unknown Input Observers which complies with a robust sliding mode control law and an adaptation law is designed in this paper considering that the time delay that may lead to the instability of the system performance is inevitable in the process of modern networked control. Then the convergence of the designed observer is verified by Lyapunov stability criterion. Finally, the observer is applied to realize the estimation of the roll diameter and tension of the bagging station of the automobile airbag production line. The experimental results verify the effectiveness of the proposed scheme.

The non-black-start generator start-up sequence optimization is an essential step for power system restoration. a multi-objective optimization model with consideration of preferences in terms of the relative importance of objectives is built to optimize generator start-up sequence and associated restoration paths simultaneously. The a priori elicitation method is used to solve the multi-objective optimization problem. The preference information is explicated by designing a subset of the whole feasible space. Then, the preferred solutions are searched in the designed region by using DE-EDA. Several Pareto optimal generator start-up sequences and restoration paths which are more desirable for the preferences can be obtained after the model is solved. Finally, a practical power system, the western power system of Shandong province in China is employed to demonstrate the effectiveness of the proposed method.

In order to solve the problem that the following-speed performance of upright vehicle is not strong caused by the conflict between the speed control and the vertical control, the control method of upright vehicle is presented based on fuzzy PI. In the design process of fuzzy PI controller, firstly, the system status of upright vehicle under different working conditions is analyzed. Secondly, the setting principle of fuzzy PI control parameters making the system to get the best response performance is made. Finally, the software simulation of the upright vehicle adopting the fuzzy PI controller and the real vehicle test are implemented respectively. The results of simulation and test show that the upright vehicle can achieve good speed following performance based on fuzzy algorithm, and the stability and robustness of the system is guaranteed.

With the aim of regeneration efficiency and braking effect, this paper focuses on cooperative control of regenerative braking and hydraulic braking for rear-wheel-drive electric vehicle (EV), and designs a model predictive controller to maintain the slip ratio within an optimal range by adjusting the braking torque continuously. Besides, a new braking torque allocation strategy is put forward in view of energy regeneration and the comfort of operation. In these regards, the proposed controller guarantees the optimal braking torque on each wheel by individually controlling the slip ratio of each tire within the stable zone. The control effects and regeneration efficiency of the control strategies in a typical deceleration process are simulated and analysed. Theoretical analyses and simulation show that the proposed controller and allocation strategy are effective for better braking performance.

This paper present a MPC based yaw rate control frame for active front steering vehicle. Firstly, by establishing the yaw rate ideal model, the reference value of the yaw rate of the vehicle is obtained. And the reference yaw rate is constrained by tyre-road friction coefficient and vehicle speed. Then the MPC controller is designed by minimizing the rate of change of the control action and deviation of yaw rate, the steering system constraint is also taken into account. And the optimization problem is solved by quadratic programming (QP) Method. Finally, the Carsim simulation software is used to verify the result, to verify the effectiveness of the proposed controller in different situations.

Shift schedule affects the optimal performance of engine and driving directly. In this paper, the optimal controller of shift schedule for Dual Clutch Transmission (DCT) is designed based on fuzzy algorithm, because there are the problems of the unexpected shift and the frequent shift in some accidental operation conditions. The throttle opening and the change rate of throttle opening are chosen as the inputs of the controller and the correction coefficient of vehicle speed the up-shift and down-shift are the output. The membership function is determined and the corresponding fuzzy control rules are formulated. In order to avoid the unexpected shift and the frequent shift in special working conditions, the controller parameters are tuning through the joint simulation of AMESim and Simulink. At last, the effectiveness of the optimal controller of the schedule is verified in the xPC-Target real-time environment.

China grows and consumes numerous types of tea, which have diverse processing techniques. West Lake Longjing Tea is one of the most famous and popular varieties of tea in China. It is difficult for consumers to assess the quality of Longjing green tea, as it usually requires well-trained experts to make the judgement based on colour, aroma, and taste. To this end, we propose a quality identification system consisting of a self-developed electronic nose and a data analysis algorithm to assess the quality of West Lake Longjing Tea based on its aroma. The equipment was tested extensively in experiments conducted on real-world data. The results show that the proposed system is capable of distinguishing the tea grades accurately. Furthermore, we studied the quality specifications of Longjing tea sold by different brands and found that standard certified brands have more accurate quality identification criteria than non-standard certified brands. Our findings will assist customers and tea factories in evaluating the quality of Longjing Tea and guide the optimisation of quality standards.

Launch control is a complex issue for AMT vehicle which focuses on minimizing clutch lockup time, minimizing friction losses during the slipping phase and ensuring smooth acceleration of the vehicle. According to the diversity and the uncertainty of start-up conditions and the complex control requirements, a nonlinear method for launch control of AMT vehicle is designed by the clutch slip speed control. Moreover, a model of the clutch system is given based on the dynamics of the system, which is a second-order equation. In order to verify the controller's effectiveness, a powertrain model of AMT vehicles is established. The model includes an engine, a clutch, a transmission, a main reducing gear and wheels. And some simulations are carried out in different working conditions according to the actual situation. The results show that the proposed controller provides a good performance in AMT vehicles' start-up progress and shows good adaptability in various working conditions.

Fine aerosol particles in the urban areas of Shanghai and Los Angeles were collected on days that were characterized by their stagnant air and high organic aerosol concentrations. They were analyzed by nanospray-desorption electrospray ionization mass spectrometry with high mass resolution (m/Δm = 100,000). Solvent mixtures of acetonitrile and water and acetonitrile and toluene were used to extract and ionize polar and nonpolar compounds, respectively. A diverse mixture of oxygenated hydrocarbons, organosulfates, organonitrates, and organics with reduced nitrogen were detected in the Los Angeles sample. A majority of the organics in the Shanghai sample were detected as organosulfates. The dominant organosulfates that were detected at two locations have distinctly different molecular characteristics. Specifically, the organosulfates in the Los Angeles sample were dominated by biogenic products, while the organosulfates of a yet unknown origin found in the Shanghai sample had distinctive characteristics of long aliphatic carbon chains and low degrees of oxidation and unsaturation. The use of the acetonitrile and toluene solvent facilitated the observation of this type of organosulfates, which suggests that they could have been missed in previous studies that relied on sample extraction using common polar solvents. The high molecular weight and low degree of unsaturation and oxidization of the uncommon organosulfates suggest that they may act as surfactants and plausibly affect the surface tension and hygroscopicity of atmospheric particles. We propose that direct esterification of carbonyl or hydroxyl compounds by sulfates or sulfuric acid in the liquid phase could be the formation pathway of these special organosulfates. Long-chain alkanes from vehicle emissions might be their precursors.

Based on the sample survey of undergraduates from Tsinghua University, Northwest Sci-Tech University of Agriculture and Forestry, Yunnan University and Yunnan Agricultural University, this paper analyzes their tea consumption and attitude towards tea consumption. Results show that more than 50% undergraduates like drinking tea, especially green tea. They would like to accept lower price tea, prefer quality to brand, and have higher degree of approval of new methods of tea drinking and tea products. However, most undergraduates lack relevant knowledge about identifying tea quality. Finally, it presents recommendations for expanding tea consumption market among undergraduates.

This paper has analyzed the magnetic circuit of three-phase 24-slot 20-pole fault tolerant permanent magnet machine in order to make the machine in electromechanical actuators have fault tolerant capability and large torque. It has been found that large inductance of fault-tolerant permanent magnet machine has been realized by increasing the stator tooth tip leakage inductance. Analytic expression of the tooth tip leakage inductance has been derived by using the flux tube approach. The tooth tip leakage inductance is affected by the slot and tooth dimensions. Sensitivity function of the slot and tooth dimensions has been introduced, some parameters which have remarkable influences on the machine performance have been found, and these parameters have been analyzed by using the finite element method. Finally, the selection zone of the slot and tooth dimensions has been acquired from the finite element results. Therefore, the analytic results can provide a reference for the fault tolerant permanent magnet machine optimization design.