System Identification and Parameter Self-Tuning Controller on Deep-Sea Mining Vehicle

System identification is a quintessential measure for real-time analysis on kinematic characteristics for deep-sea mining vehicle, and thus to enhance the control performance and testing efficiency. In this study, the system identification algorithm, recursive least square method with instrumental variables(IV-RLS), is tailored to model ‘Pioneer I’, a deep-sea mining vehicle which recently completed a 1305-meter-deep sea trial in the Xisha area of the South China Sea in August, 2021. The algorithm operates on the sensor data collected from the trial to obtain the vehicle’s kinematic model and accordingly design the parameter self-tuning controller. The performances demonstrate the accuracy of the model, and prove its generalization capability. With this model, the optimal controller has been designed, the control parameters have been self-tuned, and the response time and robustness of the system have been optimized,which validates the high efficiency on digital modelling for precision control of deep-sea mining vehicles.

Evaluation of controlled attenuation parameter in assessing hepatic steatosis in patients with autoimmune liver diseases

BACKGROUND Hepatic steatosis commonly occurs in some chronic liver diseases and may affect disease progression.AIM To investigate the performance of controlled attenuation parameter(CAP)for the diagnosis of hepatic steatosis in patients with autoimmune liver diseases(AILDs).METHODS Patients who were suspected of having AILDs and underwent liver biopsy were consistently enrolled.Liver stiffness measurement(LSM)and CAP were performed by transient elastography.The area under the receiver operating characteristic(AUROC)curve was used to evaluate the performance of CAP for diagnosing hepatic steatosis compared with biopsy.RESULTS Among 190 patients with biopsy-proven hepatic steatosis,69 were diagnosed with autoimmune hepatitis(AIH),18 with primary biliary cholangitis(PBC),and 27 with AIH-PBC overlap syndrome.The AUROCs of CAP for the diagnosis of steatosis in AILDS were 0.878(0.791-0.965)for S1,0.764(0.676-0.853)for S2,and 0.821(0.716-0.926)for S3.The CAP value was significantly related to hepatic steatosis grade(P<0.001).Among 69 patients with AIH,the median CAP score was 205.63±47.36 dB/m for S0,258.41±42.83 dB/m for S1,293.00±37.18 dB/m for S2,and 313.60±27.89 dB/m for S3.Compared with patients with nonalcoholic fatty liver disease(NAFLD)presenting with autoimmune markers,patients with AIH concomitant with NAFLD were much older and had higher serum IgG levels and LSM values.CONCLUSION CAP can be used as a noninvasive diagnostic method to evaluate hepatic steatosis in patients with AILDs.Determination of LSM combined with CAP may help to identify patients with AIH concomitant with NAFLD from those with NAFLD with autoimmune phenomena.

Control for Underactuated Reentry Aircraft in Small Angle of Attack

The control problem for under-actuated reentry vehicle like HTV-2 is considered with small angle of attack.The control strategy for an aircraft with positive lateral control departure parameter relies on strong lateral stability,which declines with the decrease of the angle of attack.Thus,to control the lateral-directional motion in a stable state is hard and even impossible in some scenarios where the under-actuated reentry vehicle,like HTV-2,flies in a low angle of attack.To address this problem,the lateral-directional open-loop motion characteristics are analyzed.The results show that in an uncontrolled state,the lateral-directional motion can automatically converge to stabilization thanks to the aerodynamic damping effect.Therefore,a method of turning-off the lateral-directional control and inviting aerodynamic damping to control can achieve stability.The six-degree-of-freedom simulation show that the lateral-directional motion can be stabilized by the aerodynamic damping,and the lateral position error caused by the bank angle deviation is limited near the zero-rise angle of attack.The control strategy is effective.

INTELLIGENT INTEGRATION CONTROL OF ROTATING DISK VIBRATION

The rotating disk is a basic machine part that is u sed widely in industry. The motion equation is transformed into the dynamic equa tion in real modal space. The personating intelligent integration is introduced to improve the existing control method. These modes that affect the transverse vibration mainly are included to simulate the vibration of rotating disk, and two methods are applied separately on condition that the sensor and the ac tuator are collocated and non collocated. The results obtained by all sided si mulations show that the new method can obtain better control effect, especially when the sensor and the actuator are non collocated.

Prospective study comparing hepatic steatosis assessment by magnetic resonance imaging and four ultrasound methods in 105 successive patients

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is becoming a major health problem,resulting in hepatic,metabolic and cardio-vascular morbidity.AIM To evaluate new ultrasonographic tools to detect and measure hepatic steatosis.METHODS We prospectively included 105 patients referred to our liver unit for NAFLD suspicion or follow-up.They underwent ultrasonographic measurement of liver sound speed estimation(SSE)and attenuation coefficient(AC)using Aixplorer MACH 30(Supersonic Imagine,France),continuous controlled attenuation parameter(cCAP)using Fibroscan(Echosens,France)and standard liver ultrasound with hepato-renal index(HRI)calculation.Hepatic steatosis was then classified according to magnetic resonance imaging proton density fat fraction(PDFF).Receiver operating curve(ROC)analysis was performed to evaluate the diagnostic performance in the diagnosis of steatosis.RESULTS Most patients were overweight or obese(90%)and had metabolic syndrome(70%).One third suffered from diabetes.Steatosis was identified in 85 patients(81%)according to PDFF.Twenty-one patients(20%)had advanced liver disease.SSE,AC,cCAP and HRI correlated with PDFF,with respective Spearman correlation coefficient of-0.39,0.42,0.54 and 0.59(P<0.01).Area under the receiver operating characteristic curve(AUROC)for detection of steatosis with HRI was 0.91(0.83-0.99),with the best cut-off value being 1.3(Se=83%,Sp=98%).The optimal cCAP threshold of 275 dB/m,corresponding to the recent EASL-suggested threshold,had a sensitivity of 72%and a specificity of 80%.Corresponding AUROC was 0.79(0.66-0.92).The diagnostic accuracy of cCAP was more reliable when standard deviation was<15 dB/m with an AUC of 0.91(0.83-0.98).An AC threshold of 0.42 dB/cm/MHz had an AUROC was 0.82(0.70-0.93).SSE performed moderately with an AUROC of 0.73(0.62-0.84).CONCLUSION Among all ultrasonographic tools evaluated in this study,including new-generation tools such as cCAP and SSE,HRI had the best performance.It is also the simplest and most available method as most ultrasound scans are equipped with this module.

Prevalence and predictors of nonalcoholic fatty liver disease in South Asian women with polycystic ovary syndrome

BACKGROUND Polycystic ovary disease(PCOS)may be a risk factor for nonalcoholic fatty liver disease(NAFLD)due to common pathogenetic pathways,including insulin resistance and obesity.Both PCOS and NAFLD are more severe in South Asian women.Data on NAFLD in South Asian women with PCOS are lacking.AIM To investigate prevalence and predictors of NAFLD and liver fibrosis in PCOS patients from South Asia.METHODS We conducted an observational routine screening program by means of transient elastography(TE)with associated controlled attenuation parameter(CAP).NAFLD was defined as CAP≥288 decibels per meter.Significant liver fibrosis(stage 2 and higher out of 4)was defined as TE measurement≥8.0 kilopascals.Elevated alanine aminotransferase(ALT)was defined as ALT>24 IU/L,as per upper limit of normal reported in South Asian women.Biochemical hyperandrogenism was defined as free androgen index>5.Predictors of NAFLD were determined by logistic regression analysis.RESULTS 101 PCOS patients(mean age 36.3 years)with no significant alcohol intake or viral hepatitis were included.Prevalence of NAFLD and significant liver fibrosis was 39.6% and 6.9%,respectively.Elevated ALT was observed in 40%and 11.5%of patients with and without NAFLD,respectively.After adjusting for duration of PCOS and insulin resistance measured by homeostasis model for assessment of insulin resistance,independent predictors of NAFLD were higher body mass index[adjusted odds ratio(aOR)1.30,95% confidence interval(CI):1.13-1.52],hyperandrogenism(aOR:5.32,95%CI:1.56-18.17)and elevated ALT(aOR:3.54,95%CI:1.10-11.47).Lifetime cardiovascular risk was higher in patients with NAFLD compared to those without NAFLD(0.31±0.11 vs 0.26±0.13).CONCLUSION Despite their young age,NAFLD diagnosed by TE with CAP is a frequent comorbidity in South Asian women with PCOS and is strongly associated with higher body mass index and hyperandrogenism.Non-invasive screening strategies could help early diagnosis and initiation of interventions,including counselling on weight loss,cardiovascular risk stratification and linkage to hepatology care where appropriate.

Solution and Analysis of the Fuzzy Volterra Integral Equations viaHomotopy Analysis Method

Homotopy Analysis Method(HAM)is semi-analytic method to solve the linear and nonlinear mathematical models which can be used to obtain the approximate solution.The HAM includes an auxiliary parameter,which is an efficient way to examine and analyze the accuracy of linear and nonlinear problems.The main aim of this work is to explore the approximate solutions of fuzzy Volterra integral equations(both linear and nonlinear)with a separable kernel via HAM.This method provides a reliable way to ensure the convergence of the approximation series.A new general form of HAM is presented and analyzed in the fuzzy domain.A qualitative convergence analysis based on the graphical method of a fuzzy HAM is discussed.The solutions sought by the proposed method show that the HAM is easy to implement and computationally quite attractive.Some solutions of fuzzy second kind Volterra integral equations are solved as numerical examples to show the potential of the method.The results also show that HAM provides an easy way to control and modify the convergence area in order to obtain accurate solutions.

Non-alcoholic steatohepatitis in liver transplant recipients diagnosed by serum cytokeratin 18 and transient elastography:A prospective study

BACKGROUND Nonalcoholic fatty liver disease(NAFLD)and nonalcoholic steatohepatitis(NASH)seem common after liver transplantation.AIM To investigate incidence and predictors of NAFLD and NASH by employing noninvasive testing in liver transplant recipients,namely controlled attenuation parameter(CAP)and the serum biomarker cytokeratin 18(CK-18).We also evaluated the diagnostic accuracy of CK-18 and CAP compared to liver histology.METHODS We prospectively recruited consecutive adult patients who received liver transplant at the McGill University Health Centre between 2015-2018.Serial measurements of CK-18 and CAP were recorded.NAFLD and NASH were diagnosed by CAP≥270 dB/m,and a combination of CAP≥270 dB/m with CK-18>130.5 U/L,respectively.Incidences and predictors of NAFLD and NASH were investigated using survival analysis and Cox proportional hazards.RESULTS Overall,40 liver transplant recipients(mean age 57 years;70%males)were included.During a median follow-up of 16.8 mo(interquartile range 15.6-18.0),63.0%and 48.5%of patients developed NAFLD and NASH,respectively.On multivariable analysis,after adjusting for sex and alanine aminotransferase,body mass index was an independent predictor of development of NAFLD[adjusted hazard ratio(aHR):1.21,95%confidence interval(CI):1.04-1.41;P=0.01]and NASH(aHR:1.26,95%CI:1.06-1.49;P<0.01).Compared to liver histology,CAP had a 76%accuracy to diagnose NAFLD,while the accuracy of CAP plus CK-18 to diagnose NASH was 82%.CONCLUSION NAFLD and NASH diagnosed non-invasively are frequent in liver transplant recipients within the first 18 mo.Close follow-up and nutritional counselling should be planned in overweight patients.

High Frequency Stability Constraints Based MMC Controller Design Using NSGA-III Algorithm

The occurrence of high frequency resonances(HFRs)has been frequently observed in several MMC-HVDC projects.To avoid these HFRs,the controller design of an MMC must satisfy two requirements:1)The controller should remain stable while in the high frequency range,and 2)MMC impedance should not possess a negative real part in the high frequency range.So far,majority of the related studies on MMC controller design have been unable to address these requirements precisely.This paper first describes the simplified high frequency MMC impedance model developed indigenously by the authors.Subsequently,the driving mechanism of two kinds of HFRs is revealed using the said developed model,including:1)MMC controller instability,and 2)Interaction instability between MMC and AC cables.Furthermore,the mathematical expressions outlining the controller stability constraint and positive damping constraint are proposed.Additionally,NSGA-III based multi-objective optimization algorithm is adopted,to identify the region most suitable for satisfying the proposed stability constraints under the MMC controller parameters.The proposed controller design method is capable of effectively evading the HFRs triggered by the incompatible MMC.The detailed time-domain simulations generated using PSCAD/EMTDC software validate the proposed designed method and endorse the improved results.

QPSO-ILF-ANN-based optimization of TBM control parameters considering tunneling energy efficiency

In recent years, tunnel boring machines (TBMs) have been widely used in tunnel construction. However, the TBM control parameters set based on operator experience may not necessarily be suitable for certain geological conditions. Hence, a method to optimize TBM control parameters using an improved loss function-based artificial neural network (ILF-ANN) combined with quantum particle swarm optimization (QPSO) is proposed herein. The purpose of this method is to improve the TBM performance by optimizing the penetration and cutterhead rotation speeds. Inspired by the regularization technique, a custom artificial neural network (ANN) loss function based on the penetration rate and rock-breaking specific energy as TBM performance indicators is developed in the form of a penalty function to adjust the output of the network. In addition, to overcome the disadvantage of classical error backpropagation ANNs, i.e., the ease of falling into a local optimum, QPSO is adopted to train the ANN hyperparameters (weight and bias). Rock mass classes and tunneling parameters obtained in real time are used as the input of the QPSO-ILF-ANN, whereas the cutterhead rotation speed and penetration are specified as the output. The proposed method is validated using construction data from the Songhua River water conveyance tunnel project. Results show that, compared with the TBM operator and QPSO-ANN, the QPSO-ILF-ANN effectively increases the TBM penetration rate by 14.85% and 13.71%, respectively, and reduces the rock-breaking specific energy by 9.41% and 9.18%, respectively.

On the Quantum Mechanical Treatment of the Bateman-Morse-Feshbach Damped Oscillator with Variable Mass

The harmonic oscillator with time-dependent (indefinite and variable) mass subject to the force proportional to velocity is studied by extending Bateman’s dual Lagrangian and Hamiltonian formalism. To study the quantum analog of such a dissipative system, the Batemann-Morse-Feshback classical Hamiltonian of the damped harmonic oscillator with varying (time-dependent) mass is canonically quantized. In order to discuss the stability of the quantum dissipative system due to the influence of varying mass and the dissipative force, we derived a formula for the vacuum state of the dissipative system with the help of quantum field theoretical framework. It is shown that the formula based on this simple model could be used to study the influence of dissipation such as the instability due to the dissipative force and/or the variable mass. It is understood that the change in the oscillator mass corresponds to a control parameter in quantum dissipative systems.

Optimization and Configuration of Control Parameters to Enhance Small-signal Stability of Hybrid LCC-MMC HVDC System

This paper investigates the small-signal stability of the hybrid high-voltage direct current(HVDC)transmission system.The system is composed of line commutated converter(LCC)as rectifier and modular multi-level converter(MMC)as inverter under weak AC grid condition.Firstly,the impact of short-circuit ratio(SCR)at inverter side on the system stability is investigated by eigen-analysis,and the key control parameters which have major impact on the dominant mode are identified by the participation factor and sensitivity analysis.Then,considering the quadratic index and damping ratio characteristic,an objective function for evaluating the system stability is developed,and an optimization and configuration method for control parameters is presented by the utilization of Monte Carlo method.The eigenvalue results and the electromagnetic transient(EMT)simulation results show that,with the optimized control parameters,the small-signal stability and the dynamic responses of the hybrid system are greatly improved,and the hybrid system can even operate under weak AC grid condition.

Screen printing process control for coating high throughput titanium dioxide films toward printable mesoscopic perovskite solar cells

Screen printing technique has been widely applied for the manufacturing of both traditional silicon solar cells and emerging photovoltaics such as dyesensitized solar cells(DSSCs)and perovskite solar cells(PSCs).Particularly,we have developed a printable mesoscopic PSC based on a triple layer scaffold of TiO2/ZrO2/carbon.The deposition of the scaftold is entirely based on screen printing process,which provides a promising prospect for low-cost photovoltaics.However,the optimal thickness of the TiO2 layer for fabricating efficient printable PSCs is much smaller than the typical thickness of screen printed films.Here,we tune the concentration of the pastes and the printing parameters for coating TiO?films,and successfully print TiO2 films with the thickness of 500-550 nm.The correlation between the thickness of the films and printing parameters such as the solid content and viscosity of the pastes,the printing speed and pressure,and the temperature has been investigated.Besides,the edge effect that the edge of the TiO2 films possesses a much larger thickness and printing positional accuracy have been studied.This work will significantly benefit the further development of printable mesoscopic PSCs.

Association between NAFLD and Risk of Colorectal Adenoma in Chinese Han Population

Background and Aims:Colorectal cancer is associated with non-alcoholic fatty liver disease(NAFLD)and other metabolic syndromes,such as obesity,abnormal blood glucose,and dyslipidemia.The relationship of NAFLD and colorectal adenoma,which is the precursor of colorectal cancer,is worthy of discussion.The aim of this study was to investigate the association between colorectal adenoma and NAFLD,colorectal adenoma and metabolic syndrome in a Chinese Han population.Methods:This retrospective study analyzed the relationship between NAFLD and colorectal adenoma in 1089 patients in Qingdao municipal hospital.Subjects were divided into a colorectal adenoma group(n=267)and a control group(n=822).NAFLD and the controlled attenuation parameter(CAP)value were determined by abdominal ultrasound and FibroScan.Results:Patients with NAFLD in the colorectal adenoma group and the control group represented 142 cases(53.2%)and 360 cases(43.8%),respectively.The mean CAP value in the colorectal adenoma group was significantly higher than that in the control group.The values of body mass index,triglyceride,high-density lipoprotein cholesterol,aspartate aminotransferase,fasting plasma glucose,and uric acid were also significantly higher in the colorectal adenoma group than in the control group.Multifactor logistic regression analysis showed that the sex,NAFLD,CAP,body mass index,triglyceride,aspartate aminotransferase,and fasting plasma glucose were significant risk factors for colorectal adenoma.Besides,NAFLD and CAP value were significant risk factors for colorectal adenoma in males but not in females.Conclusions:NAFLD and metabolic syndrome were tightly associated with the risk of colorectal adenoma in this Chinese Han population.The effect of NAFLD on colorectal adenoma was prominent in males rather than in females.

幽门螺杆菌根除治疗对非酒精性脂肪肝病患者肝脂肪变化的影响:一项随机对照先导研究

背景:幽门螺杆菌(Hp)感染可导致胰岛素抵抗和非酒精性脂肪肝病(NAFLD)。本研究旨在评估Hp根除治疗(HPET)与标准治疗(SMT)对NAFLD患者的影响。方法:80例伴有Hp感染的NAFLD患者随机分入SMT组(36例,饮食和锻炼)和HPET组(44例,除饮食和锻炼标准治疗外,予以阿莫西林+克拉红霉素+泮托拉唑三联疗法对Hp进行根除治疗)。检测受控衰减参数(CAP)、体脂参数、肝酶、血脂及包括稳态模型胰岛素抵抗指数(HOMA-IR)在内的血糖参数,比较治疗前及治疗后24周两组患者上述指标的差异。结果:64例患者纳入改良意向性分析,其中SMT组28例,HPET组36例。治疗后24周,SMT组和HPET组患者CAP评分均显著下降(P=0.002和P<0.001),但CAP变化值两组差异无统计学意义(P=0.213)。24周时,HPET组有68%的患者成功根除Hp,与治疗无应答者及SMT组患者相比,Hp根除者HOMA-IR显著改善(P=0.007)。治疗后24周,两组患者肝酶水平均显著下降,但变化值两组差异无统计学意义;血脂水平在治疗前后无显著改变,且两组间差异亦无统计学意义。HPET组患者谷胱甘肽显著下降,但变化值两组差异无统计学意义。结论:与标准治疗相比,辅以Hp根除治疗并不能进一步减轻NAFLD患者的肝脂肪变性和进一步降低肝酶水平,但成功根除Hp可以使HOMA-IR获得显著改善(临床注册号:CTRI/2017/05/008608)。

MSSSA:a multi-strategy enhanced sparrow search algorithm for global optimization

The sparrow search algorithm(SSA) is a recent meta-heuristic optimization approach with the advantages of simplicity and flexibility. However, SSA still faces challenges of premature convergence and imbalance between exploration and exploitation, especially when tackling multimodal optimization problems. Aiming to deal with the above problems, we propose an enhanced variant of SSA called the multi-strategy enhanced sparrow search algorithm(MSSSA) in this paper. First, a chaotic map is introduced to obtain a high-quality initial population for SSA, and the opposition-based learning strategy is employed to increase the population diversity. Then, an adaptive parameter control strategy is designed to accommodate an adequate balance between exploration and exploitation. Finally, a hybrid disturbance mechanism is embedded in the individual update stage to avoid falling into local optima. To validate the effectiveness of the proposed MSSSA, a large number of experiments are implemented, including 40 complex functions from the IEEE CEC2014 and IEEE CEC2019 test suites and 10 classical functions with different dimensions. Experimental results show that the MSSSA achieves competitive performance compared with several state-of-the-art optimization algorithms. The proposed MSSSA is also successfully applied to solve two engineering optimization problems. The results demonstrate the superiority of the MSSSA in addressing practical problems.

Effect of the Mixing Structure Parameters of a Self-reflux Burner on Combustion Characteristics and NO_(x)Emission

To solve the problem of low efficiency of NO_(x)emission reduction in self-reflux burners,this study is based on the concept of coordinated control of self-reflux burner structural and thermal parameters.After completing the structural design and optimization of thermal parameters,we continue to adjust the two key structural parameters:the nozzle axis distance and the length of the cylindrical section,to minimize NO_(x)emissions.These are the two parameters that chiefly affect the mixing of flue gas and fuel gas.The results show that increasing nozzle axis distance can delay the mixing of gas and air and create a more uniform oxygen concentration field for the combustion process.The maximum combustion temperature is reduced from 1973.65 K to 1935.88 K and the volume fraction of NO_(x)in the flue gas is reduced from 188.08×10^(–6)to 143.47×10^(–6).However,compared with the nozzle axis distance,the length of the cylindrical section of the burner has little effect on the mixing of the flow field.Under different cylindrical section lengths,the maximum combustion temperature does not change more than 3 K,and the volume fraction of NO_(x)in the flue gas changes within 5×10~(–6).

Discrepancies between Nonalcoholic and Metabolic-associated Fatty Liver Disease by Multiple Steatosis Assessment

Background and Aims:The redefinition of metabolic-as-sociated fatty liver disease(MAFLD)from nonalcoholic fat-ty liver disease(NAFLD)has caused a revolution in clinical practice,and the characteristics of patients with steatosis but not MAFLD remain unclear.The aims were to compare the diagnosis rate of MAFLD in NAFLD using different steato-sis methods and explore the features of non-MAFLD-NAFLD and MAFLD-non-NAFLD.Methods:A cross-sectional study enrolling consecutive individuals was conducted at three medical centers in southern China from January 2015 to September 2020.Steatosis was evaluated by liver biopsy or magnetic resonance imaging-based proton density fat frac-tion(MRI-PDFF),ultrasound,controlled attenuation param-eter(CAP),and fatty liver index(FLI).Fibrosis was assessed by the NAFLD fibrosis score,transient elastography,or shear wave elastography.Results:The study enrolled 14,985 Chi-nese adults.The agreement of MAFLD and NAFLD diagnoses were 83%for FLI,95%for ultrasound,94%for both CAP and MRI-PDFF,and 95%for liver biopsy.The body mass index,blood pressure and lipid levels among non-MAFLD-NAFLD pa-tients were similar metabolic parameters(p>0.05 for all),but not the alanine aminotransferase and the proportion of pa-tients with insulin resistance,which were significantly higher in non-MAFLD-NAFLD with significant fibrosis.Conclusions:The new MAFLD definition ruled out 5-17%of NAFLD cases.NAFLD and MAFLD-NAFLD involved more severe metabolic abnormalities than MAFLD and MAFLD-non-NAFLD.Non-MAFLD-NAFLD patients with significant fibrosis had more se-vere liver injury and increased glycemic dysregulation within the normal range.Attention should be paid to its progression.

Accuracy of non-invasive liver stiffness measurement and steatosis quantification in patients with severe and morbid obesity

Background:Vibration controlled transient elastography(VCTE)and controlled attenuation parameter(CAP™)have shown reliable performance predicting fibrosis and steatosis in normal-to overweight patients but have not been validated in severe to morbid obesity.This study aimed at determining the accuracy of VCTE,CAP™and the composite score FibroScan-AST(FAST)in patients with a body mass index(BMI)of≥35 kg/m^(2).Methods:Patients scheduled for bariatric-metabolic surgery underwent preoperative VCTE/CAP™measurement,and intraoperative liver biopsy.The feasibility and accuracy of VCTE,CAP™and the composite score FAST were retrospectively analysed to evaluate fibrosis,steatosis and active fibrotic non-alcoholic steatohepatitis[NASH+non-alcoholic fatty liver disease(NAFLD)activity score≥4+fibrosis grade≥2]using per protocol(PP)and intent to diagnose(ITD)calculation.Results:In total,170 patients(median BMI 44.4 kg/m²)were included in the study.Liver biopsy showed NASH,simple steatosis,and normal livers in 60.6%(n=103),28.8%(n=49),and 10.6%(n=18),respectively.VCTE and CAP™delivered reliable results in 90.6%(n=154/170)and 90.5%(n=134/148).The AUC(PP)of VCTE,CAP™,and FAST were 0.687(≥F2),0.786(≥F3),0.703(≥S2),0.738(S3),and 0.780(active fibrotic NASH).The AUC increased to 0.742(≥F2),0.842(≥F3),0.712(≥S2),0.780(S3),and 0.836(active fibrotic NASH)in patients below the median BMI of 44.4 kg/m².Conclusions:VCTE,CAP™and FAST show acceptable accuracy for the detection of fibrosis,steatosis and NASH in a real-life cohort of patients with obesity.Accuracy improves in patients with a BMI<44.4 kg/m^(2).