Blind Channel Estimation and Equalization

Said Elkassimi,Said Safi,B. Manaut 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.12

This paper presents the problem of blind channel estimation of a non-minimum phase system using three algorithms. These algorithms play an important role for blindly estimate the parameters of radio mobile channel. Thus studying the problem of blind channel equalization based on, the proposed algorithm, CMA and SKMAA algorithms. The simulation results in noisy environment and for different SNR values demonstrate that the proposed algorithm is more performing than other algorithms. In addition the Sign Kurtosis Maximization Adaptive Algorithm (SKMAA) is more powerful in comparison to constant modulus algorithm (CMA) at the blind channel equalization, that is to say gives the right equalization.

Highly Efficient Control of the Doubly Fed Induction Motor

Said Drid,Abdesslam Makouf,Mohamed-Said Nait-Said,Mohamed Tadjine 대한전기학회 2007 Journal of Electrical Engineering & Technology Vol.2 No.4

This paper deals with the high efficient vector control for the reduction of copper losses of the doubly fed motor. Firstly, the feedback linearization control based on Lyapunov approach is employed to design the underlying controller achieving the double fluxes orientation. The fluxes' controllers are designed independently of the speed. The speed controller is designed using the Lyapunov method especially employed to the unknown load torques. The global asymptotic stability of the overall system is theoretically proven. Secondly, a new Torque Copper Losses Factor is proposed to deal with the problem of the machine copper losses. Its main function is to optimize the torque in keeping the machine saturation at an acceptable level. This leads to a reduction in machine currents and therefore their accompanied copper losses guaranteeing improved machine efficiency. The simulation and experimental results in comparative presentation confirm largely the effectiveness of the proposed DFIM control with a very interesting energy saving contribution.

Highly Efficient Control of the Doubly Fed Induction Motor

Drid, Said,Makouf, Abdesslam,Nait-Said, Mohamed-Said,Tadjine, Mohamed The Korean Institute of Electrical Engineers 2007 Journal of Electrical Engineering & Technology Vol.2 No.4

This paper deals with the high efficient vector control for the reduction of copper losses of the doubly fed motor. Firstly, the feedback linearization control based on Lyapunov approach is employed to design the underlying controller achieving the double fluxes orientation. The fluxes# controllers are designed independently of the speed. The speed controller is designed using the Lyapunov method especially employed to the unknown load torques. The global asymptotic stability of the overall system is theoretically proven. Secondly, a new Torque Copper Losses Factor is proposed to deal with the problem of the machine copper losses. Its main function is to optimize the torque in keeping the machine saturation at an acceptable level. This leads to a reduction in machine currents and therefore their accompanied copper losses guaranteeing improved machine efficiency. The simulation and experimental results in comparative presentation confirm largely the effectiveness of the proposed DFIM control with a very interesting energy saving contribution.

New Delay Dependent Robust Stability Criteria for T–S Fuzzy Systems with Constant Delay

Said Idrissi,El Houssaine Tissir,Ismail Boumhidi,Noreddine Chaibi 제어·로봇·시스템학회 2013 International Journal of Control, Automation, and Vol.11 No.5

This paper deals with the problem of delay dependent robust stability for T–S fuzzy time delay systems. The approach based on constructing a new Lyapunov-Krasovskii functional by dividing uniformly the delay interval into N segment with N is positive integer, and using Finsler’s lemma. This new Lyapunov-Krasovskii functional is chosen with different weighted matrices corresponding to dif-ferent segments. The perturbations considered are norm bounded, and the results are expressed in terms of linear matrix inequality (LMIs). Numerical examples are provided to show the effectiveness of the present method, compared with some recent previous ones.

Clump interpolation error for the identification of damage using decentralized sensor networks

Said Quqa,Pier Francesco Giordano,Maria Pina Limongelli,Luca Landi,Pier Paolo Diotallevi 국제구조공학회 2021 Smart Structures and Systems, An International Jou Vol.27 No.2

Recent developments in the field of smart sensing systems enable performing simple onboard operations which are increasingly used for the decentralization of complex procedures in the context of vibration-based structural health monitoring (SHM). Vibration data collected by multiple sensors are traditionally used to identify damage-sensitive features (DSFs) in a centralized topology. However, dealing with large infrastructures and wireless systems may be challenging due to their limited transmission range and to the energy consumption that increases with the complexity of the sensing network. Local DSFs based on data collected in the vicinity of inspection locations are the key to overcome geometric limits and easily design scalable wireless sensing systems. Furthermore, the onboard pre-processing of the raw data is necessary to reduce the transmission rate and improve the overall efficiency of the network. In this study, an effective method for real-time modal identification is used together with a local approximation of a damage feature, the interpolation error, to detect and localize damage due to a loss of stiffness. The DSF is evaluated using the responses recorded at small groups of sensors organized in a decentralized topology. This enables the onboard damage identification in real time thereby reducing computational effort and memory allocation requirements. Experimental tests conducted using real data confirm the robustness of the proposed method and the potential of its implementation onboard decentralized sensor networks.

Analysis of mixed convection in an inclined lid-driven cavity with a wavy wall

Said Mekroussi,Driss Nehari,Mohamed Bouzit,Nord-Eddine Sad Chemloul 대한기계학회 2013 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.27 No.7

A numerical study is performed to analyze the mixed convection flow and heat transfer in a lid-driven cavity with sinusoidal wavy bottom surface. The cavity vertical walls are insulated while the wavy bottom surface is maintained at a uniform temperature higher than the top lid. A finite volume method is used to solve numerically the non-dimensional governing equations. The tests were carried out for various inclination angles ranging to 0° from 180° and number of undulation varied from 4 to 6, while the Prandtl number was kept constant Pr = 0.71. Three geometrical configurations were used namely four, five and six. The distributions of streamlines and isotherms,and the variations of local and average Nusselt numbers with the inclination angle are presented. The results of this investigation illustrate that the average Nusselt number at the heated surface increases with an increase of the number of undulations as well as the angle of inclination.

Effects of Anthropogenic Interventions on the Entisols of Al-Khoud Dam Area in a Dry Region of Oman

Said Al-Ismaily,Ali Al-Maktoumi,Anvar Kacimov,Hamad Al-Busaidi,Said Al-Saqri 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Investigating the Public Spending and Economical Growth on the Poverty Reduction in Indonesia

Said Muhammad,T. Zulham,Diana Sapha,Fitriyani,Jumadil Saputra 대한산업공학회 2019 Industrial Engineeering & Management Systems Vol.18 No.3

Poverty and income inequality are being one of the most challenging issues in many developing countries, including Indonesia. Considering the higher level of the poverty rate in Indonesia, the study about poverty reduction is crucial and currently under discussion in previous studies. Thus, this study is written to examine what is education and health budgets could be reducing the poverty rate in Indonesia. The study utilizes annual data gathered from the Central Bureau of Statistics over the 2007–2017 period and analyzed using panel data by assisting the Eviews-10. The empirical result finds that the budget allocated for education and health significantly reduce the poverty rate in Indonesia. Therefore, it is suggested that to further reduce the poverty level, the government should allocate more budget of education and health for the poor and there is a need to monitor the public service performance with the aim the allocation of expenditure can be more efficient and effective. Besides, it is necessary to increase the number of pro-poor programs such as free public health and education insurance to fulfill the basic needs of the poor.

2D Inverse Problem in a Distributed Parameter System

Said Rachidi,Rafik Channa,Asma Karama 제어·로봇·시스템학회 2013 International Journal of Control, Automation, and Vol.11 No.6

In this paper, we present a numerical solution for an inverse heat problem to estimate 2D space-wise coefficient in a parabolic system describing heat transfer. The inverse problem is recast into an optimization problem solved with a conjugate gradient method. This approach use the non linear optimization formulation by minimizing a cost function taking into account both the measured outputs of the system and the outputs calculated by means of the model. The solution is performed by using the free finite element software FreeFem. Numerical example is carried out to check the validity of the proposed method.

New Open Channel with Elliptic Sides and Horizontal Bottom

Said M. Easa,Ali R. Vatankhah 대한토목학회 2014 KSCE JOURNAL OF CIVIL ENGINEERING Vol.18 No.4

This paper presents a new general open channel section with elliptic sides and horizontal bottom. The proposed section producesspecial channel forms, such as a circular section with a horizontal bottom, a circular section, and a rectangular section. Exact andapproximate formulas for the area and perimeter of the channel are derived. These formulas are then used to develop an optimizationmodel for determining the optimal section design that minimizes the total construction cost for excavation and composite linings. Inaddition, the most hydraulically efficient elliptic section was derived. The constraints of the optimization model include channeldischarge and physical requirements, such as flow depth, top width, and side slope with fixed or depth-dependent freeboard. The costperformance of the proposed section was compared with another general open channel section (power-law) and the trapezoidalsection using different design scenarios. The results show that the new section is substantially more economical and more flexiblethan the existing power-law section, and is generally superior to the trapezoidal section.