An Approximate High Gain Observer for Speed-sensorless Estimation of Induction Motors

Rotor speed estimation for induction motors is a key problem in speed-sensorless motor drives. This paper performs nonlinear high gain observer design based on the full-order model of the induction motor. Such an effort appears nontrivial due to the fact that the full-model at best admits locally a non-triangular observable form(NTOF), and its analytical representation in the NTOF can not be obtained. This paper proposes an approximate high gain estimation algorithm, which enjoys a constructive design, ease of tuning, and improved speed estimation and tracking performance. Experiments demonstrate the effectiveness of the proposed algorithm.

Asynchronous Learning-Based Output Feedback Sliding Mode Control for Semi-Markov Jump Systems: A Descriptor Approach

This paper presents an asynchronous output-feed-back control strategy of semi-Markovian systems via sliding mode-based learning technique.Compared with most literature results that require exact prior knowledge of system state and mode information,an asynchronous output-feedback sliding sur-face is adopted in the case of incompletely available state and non-synchronization phenomenon.The holonomic dynamics of the sliding mode are characterized by a descriptor system in which the switching surface is regarded as the fast subsystem and the system dynamics are viewed as the slow subsystem.Based upon the co-occurrence of two subsystems,the sufficient stochastic admissibility criterion of the holonomic dynamics is derived by utilizing the characteristics of cumulative distribution functions.Furthermore,a recursive learning controller is formulated to guarantee the reachability of the sliding manifold and realize the chattering reduction of the asynchronous switching and sliding motion.Finally,the proposed theoretical method is substantia-ted through two numerical simulations with the practical contin-uous stirred tank reactor and F-404 aircraft engine model,respectively.

异步电机无速度传感器控制的Holtz型磁链观测器性能分析

针对异步电机无速度传感器控制中,电压型磁链观测器低速性能较差的问题,研究一种具有较好低速性能的电压型磁链观测器——Holtz型磁链观测器.基于线性化理论建立该观测器的小信号模型,得出观测器反馈系数与观测器稳定性和动态响应之间的关系.进一步分析观测器输入存在误差的情况下,反馈系数对磁链观测结果的影响.基于对观测器综合性能的分析,提出一种自适应的反馈系数设计方法.针对2.2kW的异步电机,分别在Matlab仿真平台和基于Dspace的实验平台上进行了观测器输入存在误差的仿真和实验.结果表明:当观测器阻尼系数取在1.0附近,也即反馈系数按同步角频率的2倍取值时,可以获得最佳的观测效果,并且在高速和低速下均能获得良好的动态和稳态性能.

Key Techniques of an Ecological Pattern“Planting Rice in One Season and Breeding Red Swamp Crawfish in Three Seasons” for Green Production in Lixiahe Region of Jiangsu Province

Three big field projects, independent irrigation and drainage facilities, and a blocking net, which are auxiliary projects of a green planting and breeding pattern composed of rice and red swamp crawfish （Procambarus clarkii）, spatial and temporal coupling technology of ＂planting rice in one season and breeding red swamp crawfish in three seasons＂, green fertilization technology, green prevention and control technology, control technology of water level, and throwing technology of bait in Lixiahe region of Jiangsu Province were introduced successively, which can provide technical support for the development of ecological planting and breeding patterns and realization of green production in paddy fields.

冷却肉辐照保鲜HACCP体系的建立

通过分析冷却肉辐照保鲜过程中相关环节可能出现的潜在危害,制定了冷却肉辐照保鲜过程HACCP计划,确定了关键控制点及其关键限值,构建了冷却肉辐照保鲜HACCP质量管理体系。

Stable Control of Influence Factor during Two-phase Anaerobic Digestion for Agricultural Organic Waste

Two-phase anaerobic digestion process is influenced by acid control for hydrogen production, reaction temperature, substrate detention time, sludge activity, and granular formation. Al of these technological parameters are directly related to success or failure of the system operation and treatment effect.

基于MRAS的永磁同步电机无传感器控制

针对传统机械式编码器对永磁同步电机(PMSM)交流调速系统带来的高成本、易受干扰、可靠性低且难以在复杂环境中应用等问题,对永磁同步电机数学模型、速度闭环控制方法以及目前的无传感器控制技术进行了研究,提出了一种新型的基于模型参考自适应理论(MRAS)的速度估计方法。以永磁同步电机本身作为参考模型,以含有转速变量的定子电流方程作为可调模型,以波波夫稳定性理论为基础设计了自适应律,根据自适应律判断当两个模型等效时,输出的估计转速收敛于真实值,再对转速积分得到了转子位置,实现了无速度传感器的电机控制。研究结果表明,应用该无传感器控制策略的交流调速系统避免了机械式编码器带来的限制,能够在宽调速范围内准确估计转速,动态、静态性能良好,鲁棒性强。

A Model Predictive Scheduling Algorithm inReal-Time Control Systems

Abstract-The ineffective utilization of power resources has attracted much attention in current years. This paper proposes a real-time distributed load scheduling algorithm considering constraints of power supply. Firstly, an objective function is designed based on the constraint, and a base load forecasting model is established when aggregating renewable generation and non-deferrable load into a power system, which aims to transform the problem of deferrable loads scheduling into a distributed optimal control problem. Then, to optimize the objective function, a real-time scheduling algorithm is presented to solve the proposed control problem. At every time step, the purpose is to minimize the variance of differences between power supply and aggregate load, which can thus ensure the effective utilization of power resources. Finally, simulation examples are provided to illustrate the effectiveness of the proposed algorithm.

草原畜牧业在我国国民经济和社会发展中的地位和作用

草原畜牧业在我国国民经济和社会发展中的地位和作用巴图巴根一、草原畜牧业在我国国民经济和社会发展中的地位和作用畜牧业是我国国民经济的重要组成部分，它的发展关系到国计民生，关系到牧区人民生活达小康。它所具有的经济、社会、环境三个效益的特性，决定了它的地位...

EXACT CONTROLLABILITY FOR FIRST ORDER QUASILINEAR HYPERBOLIC SYSTEMS WITH VERTICAL CHARACTERISTICS

We consider first order quasilinear hyperbolic systems with vertical characteristics. It was shown in [4] that such systems can be exactly controllable with the help of internal controls applied to the equations corresponding to zero eigenvalues. However, it is possible that, for physical or engineering reasons, we can not put any control on the equations corresponding to zero eigenvalues. In this paper, we will establish the exact controllability only by means of physically meaningfnl internal controls applied to the equations corresponding to non-zero eigenvalues. We also show the exact controllability for a very simplified model by means of switching controls.

Optimizing control of a two-span rotor system with magnetorheological fluid dampers

A control system aims at vibration reduction in a two-span rotor system with two shear mode magnetorheological （MRF） dampers is designed. A finite element model of the MRF damper- rotor system is built and used to analyze the rotor vibration characteristics. Based on Hooke and Jeeves algorithm and the numerical simulation analysis, an optimal appropriate controller is proposed and designed. Experimental results show that rotor vibration caused by unbalance is well controlled （ first critical speed region 37% , second critical speed region 42% ）. To reflect advantages of optimi- zing strategy presented and validate the intelligent optimization control technology, detailed experi- ments were developed on a two-span rotor-vibration-control platform. The influence on accuracy, rapidity and stability of optimizing control for rotor vibration are analyzed. It provides a powerful technical support for the extension and application in target and control for shafting vibration.

Cluster projective synchronization of complex networks with nonidentical dynamical nodes

We investigate a new cluster projective synchronization （CPS） scheme in time-varying delay coupled complex dynamical networks with nonidentical nodes. Based on the community structure of the networks, the controllers are designed differently for the nodes in one community, which have direct connections to the nodes in the other communities and the nodes without direct connections to the nodes in the other communities. Some sufficient criteria are derived to ensure the nodes in the same group projectively synchronize and there is also projective synchronization between nodes in different groups. Particularly, the weight configuration matrix is not assumed to be symmetric or irreducible. The numerical simulations are performed to verify the effectiveness of the theoretical results.

Modeling and Control of a Biodiesel Transesterification Reactor

Dynamic Models for predicting the concentration profiles of the reactants and product in a Continuous Stirred Tank Reactor for the transesterification of used cooking oil (triglyceride) to biodiesel has been developed using the principle of conservation of mass. The developed system of differential equations were integrated numerically using fourth order Runge-Kutta algorithm embedded in ode 45 solver of 7.5 Mathlab program. The models were validated by solving the model equations with kinetic data and other relevant data from literatures. The results and trends were similar and in agreement with those from these literatures. Simulations of the reactor to (±) step changes in the inlet flowrates of the reactants (used cooking oil and methanol) showed great effect on biodiesel production, (instability—oscillations and reduction in output concentration of biodiesel). A feedback control strategy was developed with a Proportional-Integral (PI) Controller and a close loop model was developed for control studies. The closed loop response of the reactor output (biodiesel concentration) showed continuous oscillatory response with offset. Hence the controller parameters (proportional gain Kc and integral time ) were tuned using the “On-Line Trial and Error Method” implemented using MathLab Simulink to obtain optimum values that ensured quick stability of the closed-loop system, reduced or no oscillatory response and no offset. The optimum controller parameters were: proportional gain Kc =8.306 and integral time = 17.157 minutes.

Design of the flame retardant form-stable composite phase change materials for battery thermal management system

Phase change materials have attracted significant attention owing to their promising applications in many aspects.However,it is seriously restricted by some drawbacks such as obvious leakage,relatively low thermal conductivity,and easily flame properties.Herein,a novel flame retardant form-stable composite phase change material(CPCM)with polyethylene glycol/epoxy resin/expanded graphite/magnesium hydroxide/zinc hydroxide(PEG/ER/EG/MH/ZH)has been successfully prepared and utilized in the battery module.The addition of MH and ZH(MH:ZH=1:2)as flame retardant additions can not only greatly improve the flame retardant effect but also maintain the physical and mechanical properties of the polymer.Further,the EG(5%)can provide the graphitization degree of residual char which is beneficial to building a more protective barrier.This designation of CPCM can exhibit leakage-proof,high thermal conductivity(increasing 400%-500%)and prominent flammable retardant performance.Especially at 3C discharge rate,the maximum temperature is controlled below 54.2℃and the temperature difference is maintained within 2.2℃in the battery module,which presents a superior thermal management effect.This work suggests an efficient and feasible approach toward exploiting a multifunctional phase change material for thermal management systems for electric vehicles and energy storage fields.

Indirect Output Voltage Control in Negative Output Elementary Super Lift Luo Converter Using PIC plus FLC in Discontinuous Conduction Mode

In this paper, the design of a proportional integral controller (PIC) plus fuzzy logic controller (FLC) for the negative output elementary super lift Luo converter (NOESLLC) operated in discontinuous conduction mode (DCM) is presented. In spite of the many benefits viz. the high voltage transfer gain, the high efficiency, and the reduced inductor current and the capacitor voltage ripples, it natured with non-minimum phase. This characteristic makes the control of NOESLLC cumbersome. Any attempt of direct controlling the output voltage may erupt to instability. To overcome this problem, indirect regulation of the output voltage based on the two-loop controller is devised. The savvy in the inductor current control improves the dynamic response of the output voltage. The FLC is designed for the outer (voltage) loop while the inner (current) loop is controlled by the PIC. For the developed ?19.6 V NOESLLC, the dynamic performances for different perturbations (line, load and component variations) are obtained for PIC plus FLC and compared with PIC plus PIC. The study of two cases is performed at various operating regions by developing the MATLAB/Simulink model.

Efficacy and safety of Xinglouchengqi decoction for acute ischemic stroke with constipation:study protocol for a randomized con-trolled trial

OBJECTIVE: To investigate the efficacy and safety of Xinglouchengqi(XLCQ) decoction in treatment of acute ischemic stroke with constipation.METHODS: In this prospective, multicenter, assessor-blinded, randomized controlled trial, 360 eligible participants will be randomized to the XLCQ group or the control group. Participants in the XLCQ group will receive XLCQ decoction, while those in the control group will undergo clysis therapy using glycerin enemas or oral administration of lactulose solution. Both groups will undergo a treatment period of(5 ± 2) d and a 1-month follow-up.The primary outcome measure will be the Constipation Scale score. The secondary outcome measures will include scores on the National Institutes of Health Stroke Scale, the Traditional Chinese Medicine(TCM) Stroke Scale, the Diagnostic Scale for TCM Syndromes of Ischemic Stroke and TCM Scale for Syndrome of Phlegm-heat and Fu-organ Excess.Therapeutic mechanism outcomes and safety outcomes will also be assessed. Assessments will be conducted at baseline, at the end of the treatment period, and at the follow-up. Moreover, daily visits will be scheduled to grade the status of constipation during the treatment period.DISCUSSION: The results of this study will provide scientific and objective data with which to assess the efficacy and safety of XLCQ decoction for patients with acute ischemic stroke and constipation.

Effect of Taijiquan practice versus wellness education on knee pro-prioception in patients with knee osteoarthritis:a randomized con-trolled trial

OBJECTIVE: To determine the effects of Taijiquan practice on knee proprioception in patients with knee osteoarthritis(OA).METHODS: We conducted a randomized controlled trial comparing Taijiquan with a control condition(wellness education) in patients with knee OA. The patients participated in either a 60-min Taijiquan session three times weekly or a 60-min weekly educational session, for 24 consecutive weeks. The primary outcomes were changes in knee proprioception. Secondary outcomes were changes in the Western Ontario and Mc Master University Osteoarthritis Index(WOMAC).RESULTS: After 24 weeks, compared with the control group, the Taijiquan group demonstrated better improvements in the joint position sense in knee flexion(left:-2.12°; right:-2.02°), and knee extension(left:-2.22°; right:-1.54°). In addition,the Taijiquan group showed significantly greater improvements in the WOMAC scores(P < 0.05) for knee pain(left:-3.17 points; right:-3.74 points),stiffness(left:-2.43 points; right:-2.13 points),and physical function(left:-10.99 points; right:-8.00 points), compared with the control group.CONCLUSION: A 24-week Taijiquan practice resulted in a significant improvement in knee proprioception in patients with knee OA. The present findings add increasing evidence regarding the clinical benefits of Taijiquan as a therapeutic modality for patients to improve the reflex protection of knee joints against potentially harmful forces.

Comparison of the effect and safety of Kuntai capsule and hormone replacement therapy in patients with perimenopausal syndrome:a systematic review and Meta-analysis

OBJECTIVE: To assess the effectiveness and safety of Kuntai capsule and hormone replacement therapy in treatment of perimenopausal syndrome.METHODS: Articles were retrieved from the databases Cochrane Database of Systematic Reviews,Pub Med, Chinese National Knowledge Infrastructure, China Science and Technology Journal Database, and Wanfang Database. Only randomized controlled trials were included; 15 trials involving1243 patients were identified from January 2005 to April 2015. A systemic review and Meta-analysis of publications was performed. The review was limit-ed to randomized controlled trials that compared Kuntai capsule and hormone replacement therapy to treat perimenopausal syndrome for at least 3months. The primary outcome assessed was the treatment efficacy at 3 months, including effective rate of Kupperman menopausal scores, Kupperman menopausal scores, and blood estradiol(E2) or blood follicle stimulating hormone(FSH) levels.Other outcomes assessed were safety or adverse events, such as gastrointestinal complaints, breast distending pain, or vaginal bleeding.RESULTS: Kupperman menopausal scores showed no significant difference in effective rate [odds ratio(OR): 1.05, 95% confidence intervals(CI): 0.71 to1.55] and changes in FSH level [mean difference(MD): 2.14, 95% CI:-2.36 to 6.65]. There was a significant statistical difference in Kupperman menopausal scores(MD:-1.14, 95% CI:-2.03 to-0.25)and changes in E2level(MD:-16.41, 95% CI:-18.83to-13.69). There were fewer adverse events in the Kuntai capsule group than in the hormone replacement therapy group(OR: = 0.35, 95% CI: 0.25 to0.48, P < 0.01).CONCLUSION: Compared with hormone replacement therapy, Kuntai capsule can improve perimenopausal symptoms and blood E2 levels, and reduce the incidence of adverse events.

CONTROL OF VEHICLE PLATOONS FOR HIGHWAY SAFETY AND EFFICIENT UTILITY:CONSENSUS WITH COMMUNICATIONS AND VEHICLE DYNAMICS

Platoon formation of highway vehicles is a critical foundation for autonomous or semiautonomous vehicle control for enhanced safety,improved highway utility,increased fuel economy,and reduced emission toward intelligent transportation systems.Platoon control encounters great challenges from vehicle control,communications,team coordination,and uncertainties.This paper introduces a new method for coordinated control of platoons by using integrated network consensus decisions and vehicle control.To achieve suitable coordination of the team vehicles based on terrain and environmental conditions,the emerging technology of network consensus control is modified to a weighted and constrained consensus-seeking framework.Algorithms are introduced and their convergence properties are established.The methodology employs neighborhood information through on-board sensors and V2 V or V2 I communications,but achieves global coordination of the entire platoon.The ability of the methods in terms of robustness,disturbance rejection,noise attenuation,and cyber-physical interaction is analyzed and demonstrated with simulated case studies.

Effectiveness and safety of Shenmai injection in treatment of shock:a Meta-analysis

OBJECTIVE:To evaluate the effectiveness and safety of Shenmai injection for shock.METHODS: Randomized controlled trials(RCTs)that evaluated the therapeutic effect of Shenmai injection on shock(including septic shock, cardiogenic shock, hypovolemic shock, neurogenic shock and anaphylactic shock) were included in this analysis. The major electronic databases were searched until May 2015. The methodological quality of the trials was assessed according to the Cochrane Handbook. Review Manager 5.3 and Stata 12.0 software were applied for data analysis.RESULTS: Thirty RCTs involving 2038 participants were included. The methodological quality of the trials was generally passable. The combined use of Shenmai injection and conventional medicine was significantly more effective at managing shock compared to conventional medicine alone in the outcomes of total effective rate [risk ratio(RR 1.25,95% confidence interval(CI) 1.18 to 1.31] and mortality rate [risk difference(RD)-0.10, 95% CI-0.17 to-0.02]. Likewise, improvements were observed in other metrics. Three trials reported adverse events, but no trial reported serious adverse effects.CONCLUSION: Our results indicated the potential effectiveness of Shenmai injection combined with conventional medicine treatment for shock. However, further rigorously designed trials are needed to collect and weigh up all the evidence for the use of Shenmai injection.