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Sensitive skin (SS) is a clinical syndrome defined by the occurrence of unpleasant sensations (such as stinging, burning, pain, pruritus, and tingling) in response to stimuli that normally should not provoke them. According to growing evidence, transient receptor potential vanilloid subtype 1 (TRPV1) has elevated expression in individuals with SS and is linked with the severity of SS symptoms. However, its pathogenesis is still unknown.Herein, Citrus reticulata (Tangerine) fruit extract (CR) was obtained and examined for its effect on SS with a focus on TRPV1 stimulation and expression.A recombinant hTRPV1 over-expression cell line (HaCaT-TRPV1-OE cell) was constructed to screen substances and extracts from several plants. Intracellular calcium mobilization was monitored by Flexstation 3 and a fluorescence microscope using Fluo 8 AM fluorophore. Next, immunofluorescence was used to detect the TRPV1 expression under different stimulants treated for 24 h. To investigate the relief and increased tolerance of CR to lactic acid-induced skin discomfort, clinical tests were carried out on the nasolabial folds or cheek areas.According to the obtained results, compared to HaCaT cells, HaCaT-TRPV1-OE cells showed a higher expression of TRPV1. Neuronal hyperresponsiveness in SS triggered by capsaicin (CAP), lactic acid, phenoxyethanol or nicotinamide may be through activation of TRPV1 and increased TRPV1 expression. CAP activates TRPV1 in HaCaT-TRPV1-OE cells, and more than 100 plants or chemicals were tested for their inhibitory effects before being screened for CR. CR (1%-4%) inhibited TRPV1 activation induced by CAP or phenoxyethanol or nicotinamide. Meanwhile, CR (0.25%) suppressed TRPV1 protein expression induced by phenoxyethanol or lactic acid. In vivo results showed that CR not only instantly relieved lactic acid-induced skin discomfort under 5 min but also enhanced skin tolerance to lactic acid after 7 days of continuous use.Topical application of CR showed an instant and long-lasting improvement in SS by modulating the activation and expression of TRPV1. Moreover, it has been suggested that CR might act as a TRPV1 inhibitor to reduce skin irritation or sensitivity.

The epithelial–mesenchymal transition (EMT) is a multifunctional cell process involved in the pathogenesis of numerous conditions, including fibrosis and cancer. Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal disease characterized by fibroblast accumulation and collagen deposition in the lungs. The fibroblasts involved in this process partially originate from lung epithelial cells via the EMT. Evidence suggests that the EMT contributes to progression, invasion, and metastasis of various types of cancer. We screened a series of 80 compounds for the ability to interfere with the EMT and potentially be applied as a therapeutic for IPF and/or lung cancer. We identified 2-aminopurine (2-AP), a fluorescent analog of guanosine and adenosine, as a candidate in this screen. Herein, we demonstrate that 2-AP can restore E-cadherin expression and inhibit fibronectin and vimentin expression in TGF-β1–treated A549 lung cancer cells. Moreover, 2-AP can inhibit TGF-β1-induced metastasis of A549 cells. This compound significantly attenuated bleomycin (BLM)-induced pulmonary inflammation, the EMT, and fibrosis. In addition, 2-AP treatment significantly decreased mortality in a mouse model of pulmonary fibrosis. Collectively, we determined that 2-AP could inhibit metastasis in vitro by suppressing the TGF-β1-induced EMT and could attenuate BLM-induced pulmonary fibrosis in vivo. Results of this study suggest that 2-AP may have utility as a treatment for lung cancer and pulmonary fibrosis.

Background Mindfulness-based relapse prevention (MBRP) is a method that combines cognitive behavioral relapse prevention with mindfulness practice. Research suggests that MBRP can effectively reduce withdrawal/craving in people with substance use disorder (SUD). An important part of MBRP is to practice mindfulness meditation to cope with high-risk situations for relapse, such as stimuli and situations associated with drug taking. Virtual reality cue exposure (VRCE) may be a complementary approach to MBRP as it allows for controlled and graded presentations of various high-risk situations with distal and proximal drug cues. The aim of the study is to investigate the effects of MBRP combined with VRCE, in comparison to MBRP alone or treatment as usual, on craving and emotional responses in people with methamphetamine use disorders. Method/design The study is a parallel randomized controlled study including 180 participants with methamphetamine use disorder. Three parallel groups will receive 8 weeks of MBRP combined with VRCE, MBRP alone, or treatment as usual, respectively. Craving, virtual cue reactivity, anxiety, depression, emotion regulation, mindfulness and drug-related attention bias will be assessed at pre-treatment, post-treatment, and 3 and 6 months of follow-up. Discussion This innovative study aims at investigating the effects of MBRP combined with VRCE in people with SUD. The combined intervention may have important clinical implications for relapse prevention due to its ease of application and high cost-effectiveness. This study may also stimulate research on the neuronal and psychological mechanisms of MBRP in substance use disorder. Trial registration number ChiCTR-INR-17013041.

The reliability of power transformer is very important to the safe operation of the power system. So a new method for power transformer risk assessment based on FTA, FAHP and GA is proposed. The method firstly establishes the power transformer fault tree; Secondly, it analyzes the fault tree through Fuzzy Analytic Hierarchy Process and constructs the fuzzy judgment matrix on transformer fault factors; Finally, it changes the question of solving the weight coefficients of each factor into a mathematical programming problem, and uses Genetic Algorithms to get the result so as to obtain the transformer reliability. In addition, the application result shows the effectiveness of the method above.

In this paper, a novel method based on FRA is proposed to detect both the fault and the deformation type. Firstly, a model of the transformer winding is established based on the electrical properties of winding. Secondly, as the winding frequency response curve change in accordance with the change of the parameters of winding model, the rule of the variation of winding frequency response curve is drawn out based on the model above. Thirdly, the effect of various types of winding deformation on the changes of the parameters of transformer winding model is summarized. Finally, an experimental example of the diagnosis of deformation type is conducted on a testing transformer based on the analysis of frequency response curves, hence the validation of the correctness of the simulation results.

In order to improve the rate and accuracy of wind power forecasting, the Least-Square Support Vector Machine method (LSSVM) is presented. LSSVM adopts equality constraints and defines the least-square system as the objective function, which can simplify the forecasting method to a large extent, as well as accelerate the rate of wind power forecasting. Through the analysis of the original load data, a reasonable choice on training set and test sample set is made in the simulation. Besides, many factors, such as, the temperature, wind direction, wind speed and power previous, are taken into consideration. The result shows that LSSVM is more effective than that of SVM.

In order to lower the switching losses and harmonic ratio, improve the precision of the STATCOM in the same time, the adaptive inverse control based on PAM+PWM method is proposed in this paper. The combination of PAM+PWM method is presented to enable the system to achieve the quality of low switching losses and good harmonic elimination effect. Furthermore, considering the nonlinear and time-varying characteristics which are caused by the introduction of the PAM and PWM method, an adaptive inverse control method is designed to adjust the parameters of the nonlinear mathematic model constantly to improve the precision of the control system. The results of simulation show the correctness of the proposed method.

Nowadays, the diesel engine is commonly used in industry and automobile because of its high efficiency. But there are still some problems like the emission and CO2 product need be paid more attention on. In research field people try to use advance control methods to improve diesel engine performance. Simulation becomes important in engine research which is time saving and can observe the inside reaction and parameters. This paper uses two common simulation methods: one is the three dimensional computational fluid dynamics (CFD) model and the other is the MATLAB program for engine control. PSO algorithm is used to find the optimal value and can be verified by KIVA-3V. Simulation result verify that optimal method improved MATLAB program speed and optimal value by PSO can do computational fluid dynamics analysis to let diesel engine run in better condition.

Nowadays Static Synchronous Compensator (STATCOM) has gradually become one of the representative techniques in the field of dynamic reactive power compensation in the power distribution system. This paper analyzed the topology and the voltage imbalance problem of the up and down capacitors on DC side of the three-phase four-wire STATCOM. In allusion to the imbalance problem of neutral point, a novel control strategy based on the control of zero-sequence current was proposed. By the triple close-loop control strategy, the STATCOM can achieve great control accuracy and dynamic performance. Simulation result proves that the proposed control method is effective.

Nonlinear loads generate a large amount of characteristic harmonics , deteriorate the power quality of power distribution systems in Advanced manufacturing enterprises. In this paper a novel hybrid active power filter is proposed which consists of a series thyristor switched filter (TSF) and small rated shunt active power filter(APF). TSF is tuned at fifth and seventh order harmonic frequencies. Consequently APF compensates for third and other order harmonics, unbalance current and reactive power. A new control method based on PHC strategy is presented for APF. The device has already got an application in one of the transformer substations of a automobile factory. It’s revealed that the proposed device can improve the power factor , reduce the harmonics injection and enhancement power quality of the power distribution systems.

A novel hybrid active power filter (HAPF) topology is proposed, which shows advantages of the conventional HAPF and the LCL filter in terms of reduced dc-link voltage, lower switching ripples, and less electromagnetic interference injection. To enhance the noise rejection capability of the digital controller, the resetting filters (RFs) are utilized as prefilters before the analog/digital sampling stage. A robust deadbeat current control law is derived based on the average current tracking scheme, where the effect of the RFs is favorably incorporated. To alleviate the difficulties in current controller design, the ac-side capacitor voltage of the HAPF is estimated by using the adaptive linear neural network identifier in the load current feedforward loop. Hence, a simple proportional controller is utilized in the inner current loop. Moreover, the grid current feedback and load current feedforward strategies are used to achieve precise current tracking and fast dynamic response. A 75-kVA prototype system is built for verification. The validity of the proposed HAPF and its control algorithms are confirmed by the experimental results.

The optical surface defects have a significant impact on functions and reliability of the whole optical system. In recent years, with the great attention on research of large-scale high-power solid-state laser device at home and abroad, the detection of optical surface defect has also been highly valued. Through continuous exploration, defect detection technology has made some achievements, but there are still some urgent technical problems to be solved. In this paper, the technology situation of optical surface defect will be summarized in two aspects: the surface cleanliness and surface flaws. Moreover, the technical difficulties and the problems which are currently facing will be analysis.

Inertial confinement fusion has been concerned in the year 1963. It was from the 1970s that China began to study inertial confinement fusion devices, and got lots of achievements in recent decades. The development of Inertial Confinement Fusion has an important and special meaning, whether to the national economy, military applications or for basic research. This paper comprehensively discussed the process of several large-scale ICF laser devices, the major technical indicators and the main experiment related to the devices.

The cascaded H-bridge (CHB) multilevel inverter is being recognized as the most suitable topology for high-power medium-voltage power quality conditioning applications. This paper presents mathematical modeling and effective controller design methodology for the CHB-based active power filters (APFs), which achieves dynamic reactive power and harmonic compensation. The most crucial problems in CHB-APF control are the simultaneous requirements of both accurate harmonic current compensation and the dc-link voltage stabilization among the H-bridges, which is the prerequisite for the stable operation of CHB-APF. To achieve dc-link stabilization, a novel voltage balancing algorithm is proposed by splitting the dc-link voltage control task into two parts, namely, the average voltage control and the voltage balancing control, where the sine and cosine functions of the phase angle of the fundamental component of the grid voltage are used, respectively. To ensure accurate phase tracking, a novel phase-locked loop (PLL) is proposed by using the adaptive linear neural network (ADALINE), where the grid voltage background distortion is also taken into account. The superior performance of the ADALINE-PLL is validated by comparison with the existing PLLs in literatures. Furthermore, the proportional-resonant (PR) controller is used for the reference current tracking. A separate ADALINE algorithm is applied for reference current generation (RCG) for the CHB-APF. The excellent performance of the ADALINE-based RCG scheme is verified by comparison with the existing RCG schemes, namely, the low-pass filter approach and the single-phase p − qmethod. The experimental results on the three modules CHB-APF are presented, which verifies the effectiveness of the proposed control algorithms. Copyright © 2011 John Wiley & Sons, Ltd.

This paper proposes an effective control scheme for three-phase three-wire (3P3W) active power filter using neural-based harmonic identification scheme. To achieve excellent steady state and dynamic response, the feedback control plus feed-forward control structures is utilized in the proposed control algorithms. The steady-state error minimization is achieved by the feedback loop, where the proportional integral regulators were adopted in d-axis and q-axis of the synchronous rotating reference frame synchronized with grid voltages by using the phase-locked loop. The adaptive linear combiners are utilized in the feed-forward loop, which serves the purpose of load disturbance rejection, and it significantly enhances dynamic performance of active power filter (APF). The modeling of the APF is based on the state-space modeling technique and the decoupled state-space model in synchronous d–q frame is also presented. Moreover, the mathematical formulation of the neural harmonic identification scheme and the selection of learning rate are discussed. It is found that the optimal learning rate is a compromise between the steady-state accuracy and the requirement of dynamic response. To verify the theoretical analysis, extensive simulation results are presented under both the balanced and unbalanced load conditions. The validity and effectiveness of the presented scheme is substantially confirmed by the simulation and experimental results, and it can be easily extended to applications of single-phase and three-phase four-wire APFs.

This paper proposes a novel grid synchronization scheme using a new phase-locked loop (PLL) scheme based on the adaptive linear optimal filtering (ALOF) technique. The problem formulation of the proposed ALOF is based on decomposing grid voltage signal into inner product of two vectors, namely, the vector of trigonometric functions and the vector of coefficients, corresponding to the input vector and the weight vector of the closed-loop adaptation algorithm by using least-mean-square (LMS) optimization algorithm. The coefficient of the fundamental component of the grid voltage is used as input signal for the PLL and the phase angles of the trigonometric functions are obtained from the output of the PLL recursively. The mathematical derivation of the weights updating law and the stability analysis of the ALOF–PLL are presented. Besides, the parameter selection for optimal performance is also discussed in terms of continuous domain (s-domain) analysis, discrete domain (z-domain) analysis and time domain simulations. The proposed ALOF–PLL shows the characteristic of band-pass filter at fundamental frequency and a notch filter at the harmonic frequencies. Finally, a detailed comparison with the existing single-phase and three-phase grid synchronization methods is also presented, and the proposed ALOF–PLL is found to have overwhelming advantages over the existing grid synchronization methods in terms of tracking accuracy, dynamic response and immunity to grid voltage disturbances, such as voltage sag/swell, phase-angle jump, harmonics, unbalance, random noises and frequency jump, etc. The validity and effectiveness of the ALOF–PLL is substantially confirmed by the extensive simulation results obtained from Matlab/Simulink.

A novel power factor corrector (PFC) topology based on T-type active power filter (APF) is proposed in this paper. The control scheme is based on a decoupled state-space equations of the T-type APF using proportional-integral (PI) controllers in the synchronous reference frame. The fundamental components of load currents are feed-forwarded in the current-loop controller by using synchronous frame adaptive linear neural networks to ensure a fast dynamic response. A separate PI controller is adopted in the outer voltage-loop for balancing the active power flow of the APF DC-side capacitor. The simulation and experimental results are presented, which demonstrate the validity and effectiveness of the proposed system.

A novel harmonic-free power factor correction (PFC) topology based on T-type active power filter (APF) is proposed in this paper. The proposed system has better stability characteristics compared to conventional shunt APF topologies and it is a natural filter for the non-linear load harmonic disturbances. The tuned passive filters are connected at the ac-side of the rectifier load, which are designed to provide fundamental reactive power compensation and eliminate majority of load harmonics in order to minimize the power rating and heat dissipation of the voltage source inverter (VSI). The control scheme is based on a decoupled state-space equations of the T-type APF using separate proportional-integral controllers in d-axis and q-axis of rotating reference frame synchronized with grid voltages, respectively. The fundamental components of load-side currents are feed-forwarded in the current control loop using two groups of synchronous frame adaptive linear neural networks (ADALINEs) to ensure a fast dynamic response. A proportional-integral controller is adopted in the outer voltage loop for balancing the active power flow of the dc-side capacitor of the VSI. The proposed power factor corrector topology is studied analytically and by simulation under various scenarios using Matlab/Simulink. The validity and effectiveness of the proposed topology as well as its control schemes are substantially confirmed by the simulation results.

Among linear control techniques, deadbeat control has been widely accepted as a feasible current control technique as far as the digital signal processor (DSP) implementation of active power filter (APF) is concerned. This control technique uses high gain on the error measured at one sample, to control the error ideally to zero by the next sample. The high gain makes the control very sensitive to any error or noise in the measurements, which is always there in electrical systems. Especially, the periodic noise in parallel implementation of an inverter or APF demands a higher order filter at the current transducer output, which affects the dynamic response of the system. Recently, few papers have reported the results about the use of linear periodically resetting integrators (LPRI) as filter in some electronic applications. This paper is an attempt to generalize the idea of LPRI and here we introduce the notion of linear periodically resetting filter (LPRF). The frequency characteristics of an LPRF are analyzed. Possible application of these filters in current control is studied. It is shown that these filters can be adopted to improve the performances of a current loop in APF.

A novel static synchronous compensator for reactive power compensation of distribution system (DSTATCOM) is proposed, based on the cascaded H-bridge multilevel inverter configuration. The mathematical formulation of the multilevel DSTATCOM is presented using state-space representations. A new software phase-locked loop (SPLL) is presented for grid synchronization and the obtained phase angle of the fundamental component of the grid voltage is utilized for deriving the active and reactive power balancing equations of the multilevel DSTATCOM. The proportional-resonant (PR) controller scheme is adopted for the current tracking control of the inverter, and the average dc-link voltage is controlled using a proportional-integral (PI) controller to regulate the active power flow of the DSTATCOM. Besides, the voltage balancing (VB) control among individual H-bridges is achieved by using separate PI regulators to control the difference voltage between the individual dc-link voltage and the average dc-link voltage. The validity of the proposed multilevel DSTATCOM and its control strategies is substantially confirmed by the extensive simulation results and the experimental results from the prototype system., Predložen je novi statički sinkroni kompenzator za kompenzaciju jalove snage distribucijskog sustava (DSTATCOM) zasnovan na konfiguraciji višestupanjskog pretvarača s ulančenim H-mostovima. Matematički model višerazinskog DSTATCOM-a prikazan je u prostoru stanja. Predstavljena je nova programski izvedena petlja sa zaključanom fazom namijenjena sinkronizaciji s mrežom, a dobiveni fazni kut osnovne komponente mrežnog napona koristi se za izvod jednadžbi ravnoteže aktivne i jalove snage višerazinskog DSTATCOM-a. Usvojen je koncept proporcionalno-rezonantnog regulatora za slijeđenje trajektorije struje pretvarača, a srednji napon istosmjernog međukruga upravlja se korištenjem proporcionalno-integracijskog (PI) regulatora u svrhu regulacije toka radne snage DSTATCOM-a. Osim toga, upravljanje uravnoteženjem napona među pojedinim H-mostovima ostvareno je korištenjem odvojenih PI regulatora za upravljanje razlikom napona među pojedinim istosmjernim međukrugovima te srednjim naponom istosmjernih međukrugova. Valjanost predloženog višestupanjskog DSTATCOM-a i primijenjenih upravljačkih strategija potvrđena je brojnim simulacijskim i eksperimentalnim rezultatima na prototipskoj izvedbi ovog sustava.

The conventional passive filtering has been outdated since it detune with age and the performance of passive filters is affected by the grid impedance, which may cause resonance problems. Active power filters (APFs) are attractive solutions to solve harmonics-related power quality problems due to the development of power semiconductors, control theory and digital signal processors (DSP), and they have become the first choice for power quality solutions. This paper systematically investigated 3-phase 3-wire active filter in 3-phase 3-wire and 3-phase 4-wire systems, and both the balanced and unbalanced situations are considered. It was found by various experiments, that 3-phase 3-wire active filter works quite well in 3-phase 3-wire system, however, its performance in 3-phase 4-wire system is unsatisfactory, and it may even inject unwanted harmonics to the grid under certain situations, which deteriorates power quality at the point of common coupling (PCC).

This paper proposes an LCL-filter-based hybrid active power filter for harmonic mitigation of a 10/0.4 kV residential distribution system. Adaptive linear neuron network (ADALINE) is applied for individual harmonic component extraction from distorted nonlinear load currents, and the estimated signals are used for the selective harmonic elimination (SHE) purpose in the current-loop controller. A robust deadbeat current control law is derived based on the low frequency model of the presented topology. By using the ADALINE based SHE strategy, the current-loop controller bandwidth is significantly reduced thus the stability of whole system is ensured. Both the laboratory experiments and field tests are implemented. The feasibility and effectiveness of the proposed system have been substantially confirmed by the experimental results.

A novel static synchronous compensator for reactive power compensation of distribution system (DSTATCOM) is proposed, based on the cascaded H-bridge multilevel inverter configuration. The mathemati...

Current control loops is the key element in the control structure of active power filter systems. Among linear control techniques, deadbeat control has widely been accepted as a feasible current control technique as far the DSP implementation of APF is concerned. This control technique that uses high gains on the errors measured at one sample is very sensitive to any error or noise in the measurements, which is always there in electrical systems. Especially, the periodic noise in parallel implementation of an inverter or APF demands a higher order filter at the current transducer output, which affects the system dynamic response. Recently few papers have reported the results about the use of resetting integrators as filter in some electronic applications. This paper is an attempt to show possible application of resetting integrator as filter to current control for APF, where linear control methods have better frequency characteristics and current response than general deadbeat control. Simulation and experiment verify that these filters can be adopted to improve the performances of a current loop in APF