An adaptive neuro-fuzzy sliding mode controller for MIMO systems with disturbance

This paper introduces the mathematical model of ammonia and urea reactors and suggested three methods for designing a special purpose controller. The first proposed method is Adaptive model predictive controller, the second is Adaptive Neural Network Model Predictive Control, and the third is Adaptive neuro-fuzzy sliding mode controller. These methods are applied to a multivariable nonlinear system as an ammonia–urea reactor system. The main target of these controllers is to achieve stabilization of the outlet concentration of ammonia and urea, a stable reaction rate, an increase in the conversion of carbon monoxide(CO) into carbon dioxide(CO_2) to reduce the pollution effect, and an increase in the ammonia and urea productions, keeping the NH_3/CO_2 ratio equal to 3 to reduce the unreacted CO_2 and NH_3, and the two reactors' temperature in the suitable operating ranges due to the change in reactor parameters or external disturbance. Simulation results of the three controllers are compared. Comparative analysis proves the effectiveness of the suggested Adaptive neurofuzzy sliding mode controller than the two other controllers according to external disturbance and the change of parameters. Moreover, the suggested methods when compared with other controllers in the literature show great success in overcoming the external disturbance and the change of parameters.

Re-adhesion control strategy based on the optimal slip velocity seeking method

In the railway industry, re-adhesion control plays an important role in attenuating the slip occurrence due to the low adhesion condition in the wheel-rail inter- action. Braking and traction forces depend on the normal force and adhesion coefficient at the wheel-rail contact area. Due to the restrictions on controlling normal force, the only way to increase the tractive or braking effect is to maximize the adhesion coefficient. Through efficient uti- lization of adhesion, it is also possible to avoid wheel-rail wear and minimize the energy consumption. The adhesion between wheel and rail is a highly nonlinear function of many parameters like environmental conditions, railway vehicle speed and slip velocity. To estimate these unknown parameters accurately is a very hard and competitive challenge. The robust adaptive control strategy presented in this paper is not only able to suppress the wheel slip in time, but also maximize the adhesion utilization perfor- mance after re-adhesion process even if the wheel-rail contact mechanism exhibits significant adhesion uncer- tainties and/or nonlinearities. Using an optimal slip velocity seeking algorithm, the proposed strategy provides a satisfactory slip velocity tracking ability, which was demonstrated able to realize the desired slip velocity without experiencing any instability problem. The control torque of the traction motor was regulated continuously to drive the railway vehicle in the neighborhood of the opti- mal adhesion point and guarantee the best traction capacity after re-adhesion process by making the railway vehicle operate away from the unstable region. The results obtained from the adaptive approach based on the second- order sliding mode observer have been confirmed through theoretical analysis and numerical simulation conducted in MATLAB and Simulink with a full traction model under various wheel-rail conditions.

Comparative Study of Different Decoupling Schemes for TITO Binary Distillation Column via PI Controller

This paper presents a comparative study of different decoupling control schemes for a two-input, two-output(TITO) binary distillation column via proportional-integral(PI)controller. The key idea behind this paper is designing two novel fuzzy decoupling schemes that depend on human knowledge,instead of the system mathematical model used in conventional decoupling schemes. Based on conventional and inverted decoupling schemes, fuzzy and inverted fuzzy decoupling schemes are developed. The control effect is compared using simulation results for the proposed two schemes with conventional decoupling and inverted decoupling. The proposed fuzzy decoupling schemes are easy to realize and simple to design, besides they have a good decoupling capability. Two methods are used to prove asymptotic stability of each loop and the entire closed-loop system by applying the proposed fuzzy decoupling-based PI controller.The Wood and Berry model of a binary distillation column is used to illustrate the applicability of the proposed schemes.

A Novel Scheduling Strategy for Crude Oil Blending

For those refineries which have to deal with different types of crude oil, blending is an attractive solution to obtain a quality feedstock. In this paper, a novel scheduling strategy is proposed for a practical crude oil blending process. The objective is to keep the property of feedstock, mainly described by the true boiling point (TBP) data, consistent and suitable. Firstly, the mathematical model is established. Then, a heuristically initialized hybrid iterative (HIHI) algorithm based on a two-level optimization structure, in which tabu search (TS) and differential evolution (DE) are used for upper-level and lower-level optimization, respectively, is proposed to get the model solution. Finally, the effectiveness and efficiency of the scheduling strategy is validated via real data from a certain refinery.

Autonomous process collaboration framework for C4ISR system interoperation

Interoperability plays an important role in the joint command, control, communication, computer, intelligence, surveillance, reconnaissance(C4 ISR) operations. Coordinating and integrating operational processes to fulfill a common mission are challenged by the ever-changing battlefield and hence requires a cross-organizational process management that produces an autonomous, flexible and adaptable architecture for collaborative process evolution. The traditional business process collaboration pattern is based on the predefined "public-view" perspective and cannot meet the requirement of the joint task operations. This paper proposes a flexible visibility control mechanism and a dynamic collaboration framework for modeling and generating collaborative processes. The mechanism allows collaborators to define a set of visibility rules to generate different views of the private processes for different collaborations, which gives a great flexibility for the collaboration initiator to decide on an appropriate collaboration pattern. The framework supports collaborators to dynamically and recursively add a new process or even a new organization to an existing collaboration. Moreover, a formal representation of the processes and a set of generation algorithms are provided to consolidate the proposed theory.

Restoration of space-variant blurred image based on motion-blurred target segmentation

In imaging on moving target, it is easy to get space- variant blurred image. In order to recover the image and gain recognizable target, an approach to recover the space-variant blurred image is presented based on image segmentation. Be- cause of motion blur＇s convolution process, the pixels of observed image＇s target and background will be displaced and piled up to produce two superposition regions. As a result, the neighbor- ing pixels in the superposition regions will have similar grey level change. According to the pixel＇s motion-blur character, the target＇s blurred edge of superposition region could be detected. Canny operator can be recurred to detect the target edge which parallels the motion blur direction. Then in the segmentation process, the whole target image which has the character of integral convolution between motion blur and real target image can be obtained. At last, the target image is restored by deconvolution algorithms with adding zeros. The restoration result indicates that the approach can effectively solve the kind of problem of space-variant motion blurred image restoration.

一种新颖的解决包含模式切换过渡过程的炼油厂生产调度问题的两阶段拉格朗日分解算法（英文）

To address large scale industrial processes,a novel Lagrangian scheme is proposed to decompose a refinery scheduling problem with operational transitions in mode switching into a production subproblem and a blending and delivery subproblem.To accelerate the convergence of Lagrange multipliers,some auxiliary constraints are added in the blending and delivery subproblem.A speed-up scheme is presented to increase the efficiency for solving the production subproblem.An initialization scheme of Lagrange multipliers and a heuristic algorithm to find feasible solutions are designed.Computational results on three cases with different lengths of time horizons and different numbers of orders show that the proposed Lagrangian scheme is effective and efficient.

Anti-windup Compensator Gain Design for Time-delay Systems with Constraints

Systems that are subject to both time-delay in state and input saturation are considered. We synthesize the anti-windup gain to enlarge the estimation of domain of attraction while guaranteeing the stability of the closed-loop system. An ellipsoid and a polyhedral set are used to bound the state of the system, which make a new sector condition valid. Other than an iterative algorithm, a direct designing algorithm is derived to compute the anti-windup compensator gain, which reduces the conservatism greatly. We analyze the delay-independent and delay-dependent cases, respectively. Finally, an optimization algorithm in the form of LMIs is constructed to compute the compensator gain which maximizes the estimation of domain of attraction. Numerical examples are presented to demonstrate the effectiveness of our approach.

The effect of different crystal conditions of filler metal on vacuum brazing of TiAl alloy and 42CrMo

Ti-based filler metals made by transient solidification and normal crystallization were selected for the vacuum brazing of the TiAl alloy and 42CrMo under different processing parameters. The results show that the tensile strength of the joint of transient solidified filler metal is higher than that of normal crystallized filler metal under the same processing parameters. By the analysis of scanning electron microscope（SEM） and X-ray diffracting （XRD） , it is found that the higher strength maybe caused by the generating of TiAl , TiNi and TiCu at the interface of joint made by transient solidified filler metal.

Curriculum Development and Instructional Design for “Industrial Robot Simulation Technology Training”based on Robot Studio

Taking the application of virtual simulation technology of industrial robot in teaching as the researchobject, a detailed research is conducted on the importance of course, principles of curriculum development,curriculum objectives, teaching content, teaching methods, teaching process and assessment methods in severalaspects. And the actual teaching for a semester according to this research, through the virtual simulationteaching, improved teaching efficiency, improved the industrial robot application level and ability of thestudents, reduced the equipment failure rate, and laid a solid foundation for the subsequent course.

利用声场双耳互相关函数和声源自相关函数计算音乐信号与脉冲响应卷积信号的IACC(英文)

双耳脉冲响应(BIRs)是用以表征音乐厅和歌剧院声场特征的参量.由于BIRs是表征声场的转移函数,因此,在消声室中录制的声源信号与BIRs卷积,就代表在实际声场中听到的信号.为了探究原信号的声学特征,一种有效的方法是计算其自相关函数(ACF),因为从ACF中导出的参量能与听者的主观优选良好相关.因此可以说,卷积与相关是室内声学中最重要的计算方法.文中通过将BIRs导出的双耳互相关函数(IACF)和将干信号与BIRs卷积后的IACF作比较,探讨了声源信号与声场之间的关系.在特定条件下,卷积与相关是等同的,此时,干信号与BIRs卷积后的IACC可直接由BIRs导出的IACC与干信号的ACF的有效时间τ_e来表示.

意大利歌剧院的体形、体量及材料对声场的影响(英文)

针对意大利歌剧院进行研究,着重研究建筑设计对厅堂音质的影响.对两个剧院的常规音质参量进行了测量.这两座剧院是由同一建筑师Antonio Galli Bibiena设计的,分别是波仑亚的市立剧院和曼图亚的科学剧院.二者具有相当近似的形式,但尺寸不同,所用的材料也各异,前者是用砖石建成,后者是用木料建成,因此在整修前采用了许多预应力钢筋混凝土结构.文中提供了不少数据并给出了对这些数据加以比较和分析的结果,特别是关于某些特征尺寸与扫频信号各可闻频率产生的空间听觉感受之间相关性的分析,以及若干有关材料和体型对IACC和EDT等音质参量的影响的思考.

在脉冲响应频率分析比较中对客观声学参数EDT的新认识(英文)

对于客观参量EDT,或者更确切地说,对于稳态声场衰变曲线的初始斜率与包括所有简正模式在内的平均阻尼常数之间关系的研究工作,已有一些研究者做过,如H.库特鲁夫就曾指出此参量与所测试环境的几何细节有密切关系.因此,文中选择它作为分析工具,以一种较为深入的方式,通过对一个歌剧院的研究,来检验这种关系.通过对脉冲响应在频域上进行分析,这在前人的工作中也采用过.文中对EDT从倍频程以及1/3倍频程加以研究,并利用在Matlab环境下开发的一些工具来探讨乐池的简正模式与从频带中心频率导出的最大的时间值之间的相关关系.研究表明,在所考察的环境中简正模式与衰变曲线的初始斜率之间有良好的相关关系,与自相关系数(ACF)也有良好的相关关系;研究还证实,用于分析的参量本身既是时间的函数,也是脉冲响应频率变化的函数.

Improving Date Fruit Classification Using Cycle GAN-Generated Dataset

Dates are an important part of human nutrition.Dates are high in essential nutrients and provide a number of health benefits.Date fruits are also known to protect against a number of diseases,including cancer and heart disease.Date fruits have several sizes,colors,tastes,and values.There are a lot of challenges facing the date producers.One of the most significant challenges is the classification and sorting of dates.But there is no public dataset for date fruits,which is a major limitation in order to improve the performance of convolutional neural networks(CNN)models and avoid the overfitting problem.In this paper,an augmented date fruits dataset was developed using Deep Convolutional Generative Adversarial Networks(DCGAN)and CycleGAN approach to augment our collected date fruit datasets.This augmentation is required to address the issue of a restricted number of images in our datasets,as well as to establish a balanced dataset.There are three types of dates in our proposed dataset:Sukkari,Ajwa,and Suggai.After dataset augmentation,we train our created dataset using ResNet152V2 and CNN models to assess the classification process for our three categories in the dataset.To train these two models,we start with the original dataset.Thereafter,the models were trained using the DCGAN-generated dataset,followed by the CycleGAN-generated dataset.The resulting results demonstrated that when using the ResNet152V2model,the CycleGAN-generated dataset had the highest classification performance with 96.8%accuracy,followed by the CNN model with 94.3%accuracy.

A continuous-time formulation for refinery production scheduling problems involving operational transitions in mode switching

In the refinery scheduling, operational transitions in mode switching are of great significance to formulate dynamic nature of production and obtain efficient schedules. The discrete-time formulation meets two main challenges in modeling: discrete approximation of time and large size of mixed-integer linear problem(MILP).In this article, a continuous-time refinery scheduling model, which involves transitions of mode switching, is presented due to these challenges. To reduce the difficulty in solving large scale MILPs resulting from the sequencing constraints, the global event-based formulation is chosen. Both transition constraints and production transitions are introduced and the numbers of key variables and constraints in both of the discrete-time and continuous-time formulations are analyzed and compared. Three cases with different lengths of time horizons and different numbers of orders are studied to show the efficiency of the proposed model.

Predicting Drying Performance of Osmotically Treated Heat Sensitive Products Using Artificial Intelligence

The main goal of this research is to develop and apply a robust Artificial Neural Networks(ANNs)model for predicting the characteristics of the osmotically drying treated potato and apple samples as a model heat-sensitive product in vacuum contact dryer.Concentrated salt and sugar solutions were used as the osmotic solutions at 27◦C.Series of experiments were performed at various temperatures of 35◦C,40◦C,and 55◦C for conduction heat input under vacuum(−760 mm Hg)condition.Some experiments were also performed in a pure vacuum without heat addition.Dimensionless moisture content(DMC),effective moisture diffusivity,and mass flux were considered as the performance parameters in this study.Results revealed that the osmotic dehydration using a concentrated sugar solution shows a higher reduction in the initial moisture loss of 19.87%compared to 5.3%in the salt solution.Furthermore,a significant enhancement of drying performance of about 27%in DMC was observed for both samples at vacuum and 40◦C compared to pure vacuum drying conditions.Using the experimental data,a robust artificial neural network(ANN)was proposed to describe the osmotic dehydration’s behavior on the drying process.The ANN model outputs are the dimensionless moisture contents(DMC),the diffusivity,and the mass flux.Whereas the ANN inputs were the drying time,the percent of sugar solution,and the percent of salt solution.For the ANN apple’s model,the minimum root mean square error(RMSE)values were 0.0261,0.0349 and 0.0406,for DMC,diffusivity,and mass flux,respectively.Whereas the best correlation coefficients of the above three parameters’determination values were 0.9909,0.9867 and 0.9744,respectively.For the ANN potato’s model,the minimum RMSE values were 0.0124,0.0140 and 0.0333,for DMC,diffusivity,and mass flux,respectively.And the best correlation coefficients of the parameters’values were found 0.9969,0.9968 and 0.9736,respectively.Accordingly,the ANN model’s prediction has a perfect agreement with the experimental dataset,which confirmed the ANN model’s accuracy.

Application of metaheuristic algorithms in interval type-2 fractional order fuzzy TID controller for nonlinear level control process under actuator and system component faults

Purpose–The two-tank level control system is one of the real-world’s second-order system(SOS)widely used as the process control in industries.It is normally operated under the Proportional integral and derivative(PID)feedback control loop.The conventional PID controller performance degrades significantly in the existence of modeling uncertainty,faults and process disturbances.To overcome these limitations,the paper suggests an interval type-2 fuzzy logic based Tilt-Integral-Derivative Controller(IT2TID)which is modified structure of PID controller.Design/methodology/approach–In this paper,an optimization IT2TID controller design for the conical,noninteracting level control system is presented.Regarding to modern optimization context,the flower pollination algorithm(FPA),among the most coherent population-based metaheuristic optimization techniques is applied to search for the appropriate IT2FTID’s and IT2FPID’s parameters.The proposed FPA-based IT2FTID/IT2FPID design framework is considered as the constrained optimization problem.System responses obtained by the IT2FTID controller designed by the FPA will be differentiated with those acquired by the IT2FPID controller also designed by the FPA.Findings–As the results,it was found that the IT2FTID can provide the very satisfactory tracking and regulating responses of the conical two-tank noninteracting level control system superior as compared to IT2FPID significantly under the actuator and system component faults.Additionally,statistical Z-test carried out for both the controllers and an effectiveness of the proposed IT2FTID controller is proven as compared to IT2FPID and existing passive fault tolerant controller in recent literature.Originality/value–Application of new metaheuristic algorithm to optimize interval type-2 fractional order TID controller for nonlinear level control system with two type of faults.Also,proposed method will compare with other method and statistical analysis will be presented.

Stable fuzzy controllers via LMI approach for non-linear systems described by type-2 T-S fuzzy model

Purpose-The purpose of this paper is to stabilize the type-2 Takagi-Sugeno(T-S)fuzzy systems with the sufficient and guaranteed stability conditions.The given conditions efficaciously handle parameter uncertainties by the upper and lower membership functions of the type-2 fuzzy sets(FSs).Design/methodology/approach-This paper reports on a relevant study of stable fuzzy controllers and type-2 T-S fuzzy systems and reported that the synthesis of controller for nonlinear systems described by the type-2 T-S fuzzy model is a key problem and it can be resolve to convex problems via linear matrix inequalities(LMIs).Findings-The multigain fuzzy controllers are established to improve the solvability of the stability conditions,and the authors design multigain fuzzy controllers which have extensive information of upper and lower membership grades.Consequently,the authors derive the traditional stability condition in terms of LMIs.One simulation examples illustrate the effectiveness and robustness of the derived stabilization conditions.Originality/value-The uncertain MIMO nonlinear system described by Type-2 Takagi-Sugeno(T-S)fuzzy model,and successively LMI approach used to determine the system stability conditions.The proposed control approach will give superior fault-tolerant control permanence under the actuator fault[partial loss of effectiveness(LOE)].Also the controller robust against the unmeasurable process disturbances.Additionally,the statistical z-test are carried out to validate the proposed control approach against the control approach proposed by Himanshukumar and Vipul(2019a).

A novel design of optimal intelligent fuzzy TID controller employing GA for nonlinear level control problem subject to actuator and system component fault

Purpose–The purpose of this article is about the design of controllers for conical two-tank noninteracting level(CTTNL)system in simulation.Local linearization around the equilibrium point has been done for the nonlinear CTTNL system to obtain a linearized model transfer function.Design/methodology/approach–This article deals with the design of novel optimal fractional-order tiltintegral-derivative(TID)controller using type-1 fuzzy set for the CTTNL prototype system.In this study,type-1 fuzzy TID controller parameters have been optimized through genetic algorithm(GA)and those set of values have been employed for the design of proportional-integral-derivative(PID)controller.Findings–A performance comparison between FTID and PID controller is then investigated.The analysis shows the superiority of FTID controller over PID controller in terms of integral absolute error(IAE),integral square error(ISE),integral of time multiplied absolute error(ITAE)and integral of time multiplied squared error(ITSE)integral errors.The transient and steady state performance of the FTID controller are superior as compared to conventional PID controller.In future,the FTID controller fault-tolerance capability tested on CTTNL system subject to actuator and system component(leak)faults.The detailed study of robustness in presence of model uncertainties will be incorporated as a scope of further research.Originality/value–A performance comparison between FTID and PID controller is then investigated.The analysis shows the superiority of FTID controller over PID controller in terms of IAE,ISE,ITAE and ITSE integral errors.Additionally,fault-tolerant performance of the proposed controller evaluated with fault-recovery time(F_(rt))parameter.The transient and steady state performance of the FTID controller are superior as compared to conventional PID controller.

Review of sub-synchronous interaction in wind integrated power systems: classification, challenges, and mitigation techniques

Emerging sub-synchronous interactions(SSI)in wind-integrated power systems have added intense attention after numerous incidents in the US and China due to the involvement of series compensated transmission lines and power electronics devices.SSI phenomenon occurs when two power system elements exchange energy below the synchro-nous frequency.SSI phenomenon related to wind power plants is one of the most significant challenges to main-taining stability,while SSI phenomenon in practical wind farms,which has been observed recently,has not yet been described on the source of conventional SSI literature.This paper first explains the traditional development of SSI and its classification as given by the IEEE,and then it proposes a classification of SSI according to the current research status,reviews several mitigation techniques and challenges,and discusses analysis techniques for SSI.The paper also describes the effect of the active damping controllers,control scheme parameters,degree of series compensation,and various techniques used in wind power plants(WPPs).In particular,a supplementary damping controller with converter controllers in Doubly Fed Induction Generator based WPPs is briefly pronounced.This paper provides a real-istic viewpoint and a potential outlook for the readers to properly deal with SSI and its mitigation techniques,which can help power engineers for the planning,economical operation,and future expansion of sustainable development.