ISSN Number

ISSN: 2147-9690

Turkish Journal of Engineering, Sciences and Technology

2015 Volume 3 Issue 3

 

Exponential Practical Observer Design without Lipschitz Condition for Induction Machine under Stator Resistance Variation 

Omar Naifara, Mouna Errebiib and Ines Ellouzeb  

a University of Sfax, National School of Engineering, Department of Electrical Engineering Control and energy management laboratory (CEM lab) - BP W, Sfax 3038 - Tunisia

b University of Sfax, Faculty of sciences of Sfax Department of Mathematics - BP 1171, Sfax 3000 - Tunisia

Abstract

In this paper, a new observer design for the induction machine (IM) without requirements of the global Lipschitz condition is developed. The perturbation theory is used to get a simple design of the observer ensuring its exponential practical stability in the sense of the Lyapunov. In literature, the observer robustness analysis under IM stator resistance variation did not take into account variation in transitional regime. i.e, for the prove of the observer robustness, stator resistance value is changed by the final value that is reached in continuous operation. In this work, the variation of stator resistance in transitional regime is taken into account and the proposed observer is tested under this variation.

Keywords: Nonlinear system, Lyapunov function, observer, practical exponential stability, perturbation theory, induction machine, sensorless control, Lipschitz condition.

Download PDF

 

 

A new method for choosing Cluster head in hierarchical wireless sensor networks clustering algorithms in terms of optimizing Overlapping

Amin Shahrakia, Marjan Kuchaki Rafsanjanib, Arsham Borumand Saeidc

a Science and Research Branch, Islamic Azad University, Tehran, Iran

b Department of Computer Science, Faculty of Mathematics and Computer,  Shahid Bahonar University of Kerman, Kerman, Iran

cDepartment of Mathematics, Faculty of Mathematics and Computer,  Shahid Bahonar University of Kerman, Kerman, Iran

Abstract

In recent years, Using Wireless Sensor Networks in different environments such as crisis areas, military operations, environment management systems and so on are on the increase.Lacking any fixed infrastructure, they are a popular choice for highly dynamic environments.Clustering is a subfield of topology management which has key role in the fields of energy optimization, QoS and etc. Reducing overlapping is a key factor for choosing cluster heads in terms of decreasing energy consumption, increasing Network coverage and etc. Although by using cluster heads as a router in hierarchical clustering protocols,overlapping in not preventable, reducing overlapping can help nodes for having better performance. By using proposed method networks can choose suitable cluster heads in optimum distance between each other in different layer. The consequences of using this method are increasing network coverage and optimizing energy consumption.

Keywords: Wireless Sensor Networks (WSNs), Clustering, Overlapping, Energy consumption, Network coverage.

Download PDF

 

 

 

Artificial Cooperative Search Algorithm Applied To Reliability Redundancy Optimization

Oguz Emrah Turguta

aEge University, İzmir, Bornova, Turkiye 35040

Abstract

System reliability optimization plays an important role in industrial applications. Many designers devote themselves to improve reliability of manufacturing systems and product components. Since system reliability optimization is a nonlinear mixed-integer programming problem, it is difficult to solve and requires considerable amount of computational effort. Artificial Cooperative Search (ACS) is a new population based metaheuristic algorithm which is constructed on prey/predator interaction of two artificial superorganisms.  In this paper,in order  to test the effectiveness and accuracy of the ACS algorithm, it’s applied on  seven well-known reliability optimization problems, namely, series system, series parallel system, complex bridge system, overspeed protection system, life support system in a space capsule, N-stage mixed system and 10 and 15 unit structure system. Finally, the results are compared with some other algorithms’ results in the literature. Simulation results show that ACS algorithm outperforms other algorithms in terms of best solution.

Keywords:  Artificial Cooperative Search, Mixed Integer Programming, Optimization, Reliability Problem 

Download PDF

 

 

A Comparative Study Of The Implementation Wind Farms Integration Based On Maximization Of Voltage Stability And System Loadability

Mehrdad Ahmadi Kamarposhtia, Soodabeh Soleymania , Seyed Babak Mozafaria  and Seyed Mehdi Hosseinib

aDepartment of Electrical Engineering, Science and Research Branch, Islamic Azad University, IRAN

bDepartment of Electrical Engineering, Babol Noshirvani University of Technology, IRAN

Abstract

This paper presents voltage stability in power systems which are connected to the wind farm generators. Two steady state models of wind generators, squirrel cage and doubly feed induction generators have been used. P-V curve that is used shows the maximum loading factor when the wind farm was installed. A modified IEEE 14 bus system has been selected to show the performance. For improvement of voltage stability, parallel FACTS devices are selected. Results show that STATCOM can improve the maximum loading factor of both wind generators better than SVC.

Keywords: FACTS devices, voltage stability, squirrel cage induction generator, doubly fed induction generator

Download PDF

 

 

Paper Mobile Patient Monitoring: an NFC-based Proposal for Family Practice

Bülent Çobanoğlua, O.İbrahim Fırat Atmacab and Neziha Akalınc

a Sakarya University, Mechatronic Engineering, Sakarya, Turkey

b Sakarya University, Mechatronic Engineering, Sakarya, Turkey

c Istanbul Technical University, Computer Engineering, Istanbul/Turkey

Abstract

Health services are one of the most important needs in human life. To give more qualified services to their patients’ health services use the innovative IT solutions to improve health care systems and to give better service. Near Field Communication (NFC) is a technology for contact-less short-range communication via Radio Frequency Identification (RFID) by using magnetic field induction for communication between electronic devices.  Mobile phones are the most promising target devices to act as an NFC reader. Usage of NFC in patient monitoring systems aims to accelerate medical respond to patients in medically compromised like the elderly patients with requirement medical care, patients with tension and diabetic patients. Our study reveals that NFC enabled mobile phones in telemedicine services make improvement in emergent medical respond which provides early diagnosis and cure, correct evaluation with collected instantaneously data and direct communication with responsible persons for family practice.

Keywords: Family practice, Near Field Communication (NFC), Patient monitoring systems, Telemedicine

Download PDF

 

 

Land Use Changes Analysis Using GIS, Remote Sensing And Landscape Metrics, Case Study: Golpayegan City, IRAN

M. Mirzaeia and K.Shayestehb

aPhd student in environmental science, Malayer University

bAssistant Professor, Department of Environmental Sciences, Malayer University

Abstract

Today, human development and greater mastery over the environment has caused environmental changes occur faster and wider than before. Thus having information about these changes is essential for management and restoration of ecosystem`s sustainable normal order. Landscape metrics are quantitative tools of landscape situation. These metrics can give us a lot of information about the structure and changes of landscape components. This study has been performed to investigate the landscape changes in Golpayegan city located in Isfahan province in central Iran. In order to preparation of land cover maps and change analysis, satellite imagery 1972 (TM) and 2010 (ETM +) and class area, patch density, number of patches, mean patch size, edge density and mean shape index metrics were used. For analysis of landscape fragmentation, various metrics of landscape pattern in class level were calculated using the Fragstats software. Landscape metrics analysis shows that medium ranges have been replaced by agricultural lands, poor ranges, residential lands and bare lands. According to the results, increasing in the number of patches and decreasing in the area average are important indicators of decomposition that indicate the destruction and fragmentation of the landscape. The results of this study can be used in land evaluation, environmental studies and planning and integrated management for rational utilization of natural resources and reducing of resource degradation.

Keywords: land use, landscape metrics, Golpayegan city, Fragstats software.

Download PDF

 

 

 

Optimization Of Iron Leaching For Upgradation Of High Grade Quartz Sample Of India By Using Central Composite Rotatable Design

T. Laxmia and R. Bhima Raoa

a CSIR –Institute of Minerals and Materials Technology,  Bhubaneswar-751 013, Odisha, India

Abstract

In this study, a Central Composite Rotatable Design (CCRD) combined with Response Surface Methodology (RSM) used for modeling and optimizing of some process parameters of leaching for the dissolution of iron from high grade quartz sample. The five significant operational parameters of leaching, which are particle size, acid concentration, solid/liquid ratio, time of agitation and temperature, are varied and the results evaluated with the CCRD design, Response Surface Methodology and also Quadratic Programming (QP). Second-order response functions were produced for percentage of iron extraction from high grade quartz sample. Predicted values of response (iron removal, %) obtained using model equation was in good agreement with the experimental values (R2 value of 0.94). Based on Central composite Rotatable Design (CCRD), three dimensional plots and the contour plots, the optimal leaching conditions of iron from quartz sample are,particle size, 75 micron; acid concentration, 60 mol/l; solid/liquid ratio, 0.3125 g/l; temperature, 80 Degree C and time of agitation, 17.5 min. At these optimum process variables the analysed silica percentage of leached sample contains 99.8% SiO2. This process of iron leaching is one of the best processes to obtain 99.8% SiO2, which is a suitable raw material for electronic industries.

Keywords: Optimization; Leaching; Upgradation; Central Composite Rotatable Design; Response surface Methodology

Download PDF

 

Online Submission

You need to register in order to add your article to the article tracking system. Please register and submit your manuscript electronically via online submission systems.

Free business joomla templates