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Classical state feedback controller for nonlinear systems using mean value theorem: closed loop-FOC of

Abrar ALLAG,Abdelhamid BENAKCHA,Meriem ALLAG,Ismail ZEIN,Mohamed Yacine AYAD

《能源前沿(英文)》 2015年 第9卷 第4期   页码 413-425 doi: 10.1007/s11708-015-0379-1

摘要: The problem of state feedback controllers for a class of Takagi-Sugeno (T-S) Lipschitz nonlinear systems is investigated. A simple systematic and useful synthesis method is proposed based on the use of the differential mean value theorem (DMVT) and convex theory. The proposed design approach is based on the mean value theorem (MVT) to express the nonlinear error dynamics as a convex combination of known matrices with time varying coefficients as linear parameter varying (LPV) systems. Using the Lyapunov theory, stability conditions are obtained and expressed in terms of linear matrix inequalities (LMIs). The controller gains are then obtained by solving linear matrix inequalities. The effectiveness of the proposed approach for closed loop-field oriented control (CL-FOC) of permanent magnet synchronous machine (PMSM) drives is demonstrated through an illustrative simulation for the proof of these approaches. Furthermore, an extension for controller design with parameter uncertainties and perturbation performance is discussed.

关键词: Takagi-Sugeno (T-S) fuzzy systems     sector nonlinearity     nonlinear controller     linear matrix inequality (LMI) approach     differential mean value theorem (DMVT)     field oriented control (FOC)     linear parameter varying (LPV)    

HVAC系统的模糊预测函数控制器设计

吕红丽,贾磊,王雷,高瑞

《中国工程科学》 2006年 第8卷 第9期   页码 65-68

摘要:

针对暖通空调HVAC系统中由于存在高度非线性、时变特征以及扰动和不确定性等因素而难以控制的特点,提出基于Takagi-Sugeno(T-S)模糊模型的预测函数控制器设计方法。该方法通过最小二乘辨识算法建立系统的模糊T-S模型,然后基于模糊全局线性化预测模型,采用预测函数控制算法设计系统控制律。仿真实验结果表明该算法是一种跟踪性能好、鲁棒性强的有效控制方法。

关键词: T-S模糊模型     预测函数控制     最小二乘算法     HVAC系统    

A novel approach for remanufacturing process planning considering uncertain and fuzzy information

《机械工程前沿(英文)》 2021年 第16卷 第3期   页码 546-558 doi: 10.1007/s11465-021-0639-1

摘要: Remanufacturing, as one of the optimal disposals of end-of-life products, can bring tremendous economic and ecological benefits. Remanufacturing process planning is facing an immense challenge due to uncertainties and fuzziness of recoverable products in damage conditions and remanufacturing quality requirements. Although researchers have studied the influence of uncertainties on remanufacturing process planning, very few of them comprehensively studied the interactions among damage conditions and quality requirements that involve uncertain, fuzzy information. Hence, this challenge in the context of uncertain, fuzzy information is undertaken in this paper, and a method for remanufacturing process planning is presented to maximize remanufacturing efficiency and minimize cost. In particular, the characteristics of uncertainties and fuzziness involved in the remanufacturing processes are explicitly analyzed. An optimization model is then developed to minimize remanufacturing time and cost. The solution is provided through an improved Takagi–Sugeno fuzzy neural network (T-S FNN) method. The effectiveness of the proposed approach is exemplified and elucidated by a case study. Results show that the training speed and accuracy of the improved T-S FNN method are 23.5% and 82.5% higher on average than those of the original method, respectively.

关键词: remanufacturing     uncertain and fuzzy information     process planning     T-S FNN    

Application of metal oxides-based nanofluids in PV/T systems: a review

《能源前沿(英文)》 2022年 第16卷 第3期   页码 397-428 doi: 10.1007/s11708-021-0758-8

摘要: Having the wide application of metal oxides in energy technologies, in recent years, many researchers tried to increase the performance of the PV/T system by using metal oxide-based nanofluids (NFs) as coolants or optical filters or both at the same time. This paper summarizes recent research activities on various metal oxides (Al2O3, TiO2, SiO2, Fe3O4, CuO, ZnO, MgO)-based NFs performance in the PV/T system regarding different significant parameters, e.g., thermal conductivity, volume fraction, mass flowrate, electrical, thermal and overall efficiency, etc. By conducting a comparative study among the metal oxide-based NFs, Al2O3/SiO2-water NFs are mostly used to achieve maximum performance. The Al2O3-water NF has a prominent heat transfer feature with a maximum electrical efficiency of 17%, and a maximum temperature reduction of PV module of up to 36.9°C can be achieved by using the Al2O3-water NF as a coolant. Additionally, studies suggest that the PV cell’s efficiency of up to 30% can be enhanced by using a solar tracking system. Besides, TiO2-water NFs have been proved to have the highest thermal efficiency of 86% in the PV/T system, but TiO2 nanoparticles could be hazardous for human health. As a spectral filter, SiO2-water NF at a size of 5 nm and a volume fraction of 2% seems to be very favorable for PV/T systems. Studies show that the combined use of NFs as coolants and spectral filters in the PV/T system could provide a higher overall efficiency at a cheaper rate. Finally, the opportunities and challenges of using NFs in PV/T systems are also discussed.

关键词: metal oxide     nanofluids (NFs)     nanoparticles (NPs)     optical filter     PV/T systems     solar energy    

先进城市与社会的高性能抗震结构

Jiro Takagi, Akira Wada

《工程(英文)》 2019年 第5卷 第2期   页码 184-189 doi: 10.1016/j.eng.2018.11.023

Unified power quality conditioner based on a three-level NPC inverter using fuzzy control techniques

Salim CHENNAI,M-T BENCHOUIA

《能源前沿(英文)》 2014年 第8卷 第2期   页码 221-239 doi: 10.1007/s11708-014-0317-7

摘要: This paper presents a novel and efficient control scheme for unified power quality conditioner (UPQC) based on three-level neutral point clamped (NPC) inverter using fuzzy logic techniques. The proposed UPQC is capable of mitigating source current harmonics and compensate all voltage disturbances such as voltage sags, swells, unbalances and harmonics. It is designed by the integration of series and shunt active filters (AFs) sharing a common DC bus capacitor. The DC voltage is maintained constant using proportional integral voltage controller. The synchronous reference frame (SRF) theory is used to get the reference signals for shunt active power filters (APFs) and the power reactive theory (p-q theory) for series APFs. The shunt and series APF reference signals derived from the control algorithm and sensed signals are injected in two controllers to generate switching signals. To improve the UPQC capability, fuzzy logic techniques are introduced to control the series APF. The performances of the proposed UPQC system are evaluated in terms of power factor correction, mitigation of voltage or current harmonics and all other voltage disturbances compensation using Matlab-Simulink software and SimPowerSystem toolbox. The simulation results illustrate the performance of the proposed UPQC at the common connection point of the nonlinear load to improve the power energy quality.

关键词: three-level neutral point clamped (NPC) inverter     unified power quality conditioner (UPQC)     current harmonics mitigation     fuzzy logic controller     voltage disturbance compensation     shunt active filter     series active filter     power quality energy improvement    

Requirements in performance measurement systems of construction projects from the lean production perspective

BARTH, Carlos T. FORMOSO

《工程管理前沿(英文)》 2021年 第8卷 第3期   页码 442-455 doi: 10.1007/s42524-020-0108-2

摘要: Performance measurement (PM) generates useful data for process control, facilitates communication between different sectors, and helps to align efforts on the most important aspects of the business. Thus, PM plays a key role in the management of projects and organizations. PM is also important in the implementation of lean production principles and methods, such as reducing the share of nonvalue-adding activities, increasing process transparency, building continuous improvement into the process, and benchmarking. Moreover, the adoption of the lean production philosophy requires changes in PM. Despite its importance, limited studies have been conducted on the use of PM systems for assessing the impact of lean production programs in construction projects. In addition, studies on how lean companies (or projects) use performance measurement and to what extent the indicators adopted reflect the result of actions that have been undertaken are limited. This study proposes a set of requirements in PM systems of construction projects from the perspective of lean production and a taxonomy of performance metrics for lean production systems. Five empirical studies have been carried out on construction companies from South America involved in the implementation of lean production systems. The scope of this investigation is limited to the construction projects as production systems rather than PM at the level of construction organizations.

关键词: performance measurement     lean construction     production management     continuous improvement     metrics    

Resiliency of steel and composite structures

Roberto T. LEON,Yu GAO

《结构与土木工程前沿(英文)》 2016年 第10卷 第3期   页码 239-253 doi: 10.1007/s11709-016-0349-7

摘要: This paper is divided into two parts. The first part addresses the resiliency and sustainability of steel and composite structures from a fundamental standpoint, and it is intended as an introduction to the other six papers that form part of this issue related to resiliency of steel structural systems in seismic areas. The paper posits the idea that resiliency is a characteristic that embodies sustainability rather than the traditional opposite point of view. The second part of the paper is divided into two sections, with the first section describing a number of retrofit technologies with recentering characteristics that have been developed for small, seismically deficient buildings in developing countries. The second section describes an innovative connection between circular concrete filled tubes and conventional beams with reduced flange sections consisting of steel and shape memory alloy bars and end plates. The connection has partial restraint behavior and strong recentering properties. This connection is used to demonstrate that some creative thinking can lead to innovative ways of addressing issues related to robustness, resiliency and sustainability of steel structures.

关键词: steel structures     resiliency     sustainability     recentering systems     shape memory alloys    

Finite element analysis and structural design of pretensioned inverted T-beams with web openings

Hock Tian CHENG, Bashar S. MOHAMMED, Kamal Nasharuddin MUSTAPHA

《结构与土木工程前沿(英文)》 2009年 第3卷 第2期   页码 148-157 doi: 10.1007/s11709-009-0030-5

摘要: This paper presents the results of a research project aimed at providing standard circular web openings to the popular precast pretensioned inverted T-beam. Opening size and placement and required materials strengths were investigated. In this paper the nonlinear analysis and design of simply supported pretensioned inverted T-beam with circular web openings are presented. Two design parameters are varied: opening location and number of openings. The results from nonlinear finite element analysis were substantiated by test results from five pretensioned inverted T-beams with web opening and one solid beam. Good agreement is shown between the theoretical and the experimental results. The test results obtained from this investigation show that the performance of the specimens with web openings is almost identical to that of the specimen without web openings. A simple design method for pretensioned inverted T-beam with circular web openings is proposed.

关键词: prestressed concrete     inverted-T beam     web opening    

Fault classification and reconfiguration of distribution systems using equivalent capacity margin method

Sathish KUMAR, T. JAYABARATHI

《能源前沿(英文)》 2012年 第6卷 第4期   页码 394-402 doi: 10.1007/s11708-012-0211-0

摘要: This paper investigates the capability of support vector machines (SVM) for prediction of fault classification and the use of the concept of equivalent capacity margin (ECM) for restoration of the power system. The SVM, as a novel type of machine learning based on statistical learning theory, achieves good generalization ability by adopting a structural risk minimization (SRM) induction principle aimed at minimizing a bound on the generalization error of a model rather than the minimization of the error on the training data only. Here, the SVM has been used as a classification. The inputs of the SVM model are power and voltage values. An equation has been developed for the prediction of the fault in the power system based on the developed SVM model. The next steps of this paper are the restoration and reconfiguration by using the ECM concept, the development of a code, and the testing of the results with various load outages, which have been executed for a 12 load system.

关键词: support vector machines (SVM)     structural risk minimization (SRM)     equivalent capacity margin (ECM)     restoration     fault classification    

Life cycle cost savings analysis on traditional drainage systems from low impact development strategies

Pengfei ZHANG, Samuel T. ARIARATNAM

《工程管理前沿(英文)》 2021年 第8卷 第1期   页码 88-97 doi: 10.1007/s42524-020-0063-y

摘要: Areas that are covered with natural vegetation have been converted into asphalt, concrete, or roofed structures and have increased surface impermeability and decreased natural drainage capability. Conventional drainage systems were built to mimic natural drainage patterns to prevent the occurrence of waterlogging in developed sites. These drainage systems consist of two major components: 1) a stormwater conduit system, and 2) a runoff storage system. Runoff storage systems contain retention basins and drywells that are used to store and percolate runoff, whereas conduit systems are combination of catch basins and conduit pipes used to collect and transport runoff. The construction of these drainage systems is costly and may cause significant environmental disturbance. In this study, low impact development (LID) methods that consist of extensive green roofs (GRs) and permeable interlocking concrete pavements (PICPs) are applied in real-world construction projects. Construction project documents were reviewed, and related cost information was gathered through the accepted bidding proposals and interviews of specialty contractors in the metropolitan area of Phoenix, Arizona. Results indicate that the application of both LID methods to existing projects can save an average of 27.2% in life cycle costs (LCC) for a 50-year service life and 18.7% in LCC for a 25-year service life on the proposed drainage system, respectively.

关键词: low impact development     traditional drainage system     hydraulic benefits     life-cycle cost    

Ultimate load analysis of pretensioned inverted T-beams with circular web openings

Hock Tian CHENG , Bashar S. MOHAMMED , Kamal Nasharuddin MUSTAPHA ,

《结构与土木工程前沿(英文)》 2009年 第3卷 第3期   页码 262-271 doi: 10.1007/s11709-009-0031-4

摘要: The provision of transverse openings in floor beams to facilitate the passage of utility pipes and service ducts not only results in a more systematic layout of pipes and ducts, it also translates into substantial economic savings in the construction of a multi-storey building. In this paper, ultimate load analysis of statically loaded simply supported pretensioned inverted T-beams with circular web openings is presented. Major findings relevant to ultimate load analysis of pretensioned beams with circular web openings are summarized. An attempt has been made to answer the frequently asked questions related to ultimate load analysis on multiple circular web openings. It has been shown that the analysis method for pretensioned beams with multiple large circular web openings can be further simplified without sacrificing rationality.

关键词: pretensioned inverted T-beam     web opening    

Performance design of a cryogenic air separation unit for variable working conditions using the lumped parameter model

Jinghua XU, Tiantian WANG, Qianyong CHEN, Shuyou ZHANG, Jianrong TAN

《机械工程前沿(英文)》 2020年 第15卷 第1期   页码 24-42 doi: 10.1007/s11465-019-0558-6

摘要: Large-scale cryogenic air separation units (ASUs), which are widely used in global petrochemical and semiconductor industries, are being developed with high operating elasticity under variable working conditions. Different from discrete processes in traditional machinery manufacturing, the ASU process is continuous and involves the compression, adsorption, cooling, condensation, liquefaction, evaporation, and distillation of multiple streams. This feature indicates that thousands of technical parameters in adsorption, heat transfer, and distillation processes are correlated and merged into a large-scale complex system. A lumped parameter model (LPM) of ASU is proposed by lumping the main factors together and simplifying the secondary ones to achieve accurate and fast performance design. On the basis of material and energy conservation laws, the piecewise-lumped parameters are extracted under variable working conditions by using LPM. Takagi–Sugeno (T–S) fuzzy interval detection is recursively utilized to determine whether the critical point is detected or not by using different thresholds. Compared with the traditional method, LPM is particularly suitable for “rough first then precise” modeling by expanding the feasible domain using fuzzy intervals. With LPM, the performance of the air compressor, molecular sieve adsorber, turbo expander, main plate-fin heat exchangers, and packing column of a 100000 Nm O /h large-scale ASU is enhanced to adapt to variable working conditions. The designed value of net power consumption per unit of oxygen production (kW/(Nm O )) is reduced by 6.45%.

关键词: performance design     air separation unit (ASU)     lumped parameter model (LPM)     variable working conditions     T–S fuzzy interval detection    

Gained switching-based fuzzy sliding mode control for a discrete-time underactuated robotic system with

Hui LI, Ruiqin LI, Jianwei ZHANG

《机械工程前沿(英文)》 2021年 第16卷 第2期   页码 353-362 doi: 10.1007/s11465-020-0620-4

摘要: This study proposes a gained switching-based discrete-time sliding mode control method to address the chattering issue in disturbed discrete-time systems, which suffer from various unknown uncertainties. Through the new structure of the designed reaching law, the proposed method can effectively increase the convergence speed while guaranteeing chattering-free control. The performance of controlling underactuated robotic systems can be further improved by the adoption of fuzzy logic to perform adaptive online hyper-parameter tuning. In addition, an underactuated robotic system with uncertainties is studied to validate the effectiveness of the proposed reaching law. Results reveal the dynamic performance and robustness of the proposed reaching law in the studied system and prove the proposed method’s superiority over other state-of-the-art methods.

关键词: sliding-mode control     robot control     discrete-time uncertain systems     fuzzy logic    

任意隶属度函数模糊系统的逼近特性

张钊,裴燕玲,郑爱红

《中国工程科学》 2005年 第7卷 第8期   页码 47-50

摘要:

以四边形隶属函数作为一般的隶属函数,利用Stone-Weierstrass定理对任意隶属函数的模糊系统任意逼近紧集上的任意连续实函数进行证明,是对基本模糊系统逼近任意连续非线性函数理论的推广,模糊系统对任意非线性函数的逼近性能,是模糊系统用于系统辩识的理论依据。

关键词: 模糊系统     隶属函数     逼近    

标题 作者 时间 类型 操作

Classical state feedback controller for nonlinear systems using mean value theorem: closed loop-FOC of

Abrar ALLAG,Abdelhamid BENAKCHA,Meriem ALLAG,Ismail ZEIN,Mohamed Yacine AYAD

期刊论文

HVAC系统的模糊预测函数控制器设计

吕红丽,贾磊,王雷,高瑞

期刊论文

A novel approach for remanufacturing process planning considering uncertain and fuzzy information

期刊论文

Application of metal oxides-based nanofluids in PV/T systems: a review

期刊论文

先进城市与社会的高性能抗震结构

Jiro Takagi, Akira Wada

期刊论文

Unified power quality conditioner based on a three-level NPC inverter using fuzzy control techniques

Salim CHENNAI,M-T BENCHOUIA

期刊论文

Requirements in performance measurement systems of construction projects from the lean production perspective

BARTH, Carlos T. FORMOSO

期刊论文

Resiliency of steel and composite structures

Roberto T. LEON,Yu GAO

期刊论文

Finite element analysis and structural design of pretensioned inverted T-beams with web openings

Hock Tian CHENG, Bashar S. MOHAMMED, Kamal Nasharuddin MUSTAPHA

期刊论文

Fault classification and reconfiguration of distribution systems using equivalent capacity margin method

Sathish KUMAR, T. JAYABARATHI

期刊论文

Life cycle cost savings analysis on traditional drainage systems from low impact development strategies

Pengfei ZHANG, Samuel T. ARIARATNAM

期刊论文

Ultimate load analysis of pretensioned inverted T-beams with circular web openings

Hock Tian CHENG , Bashar S. MOHAMMED , Kamal Nasharuddin MUSTAPHA ,

期刊论文

Performance design of a cryogenic air separation unit for variable working conditions using the lumped parameter model

Jinghua XU, Tiantian WANG, Qianyong CHEN, Shuyou ZHANG, Jianrong TAN

期刊论文

Gained switching-based fuzzy sliding mode control for a discrete-time underactuated robotic system with

Hui LI, Ruiqin LI, Jianwei ZHANG

期刊论文

任意隶属度函数模糊系统的逼近特性

张钊,裴燕玲,郑爱红

期刊论文