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.

The burden and management strategies of hypertensive crisis in adult patients presenting to emergency departments of district and regional hospitals in Sub-Saharan Africa

Said S. Kilindimo,Abdulkarim Ahmed,Alphonce N. Simbila,Raynald Harrison,Lucy Shirima,Farida Abdallah,Aliasghar G. Mukhtar,Juma Mfinanga,Joseph Saika,Kisanga Emanuel,Hendry R. Sawe 대한고혈압학회 2023 Clinical Hypertension Vol.29 No.-

Background Hypertensive crisis is among the causes of morbidity and mortality in adult patients with hypertension in Sub-Saharan Africa. We aimed to determine the burden, risk factors and describe the management strategies of hypertensive crisis among adult patients seen at emergency departments of district and regional hospitals in Tanzania. Methods This was a prospective multicenter longitudinal study which included all 162 district and regional hospitals in Tanzania. It was part of the Tanzania Emergency Care Capacity Survey (TECCS), a large assessment of burden of acute illness and emergency care capacity in Tanzania. Adult patients who presented to emergency departments with blood pressure ≥ 180/110mmHg were enrolled. Demographics, clinical presentation, management, and 24-hours outcomes were recorded using a structured case report form. Descriptive statistics were summarized in frequency and median, while logistic regression was used to evaluate the association between risk factors and presence of hypertensive crisis. Results We screened 2700 patients and enrolled 169 adults, henceforth proportion of adult patients with hypertensive crisis was 63 per 1000. Median age was 62 years (IQR 50–70 years) and predominantly females, 112 (66.3%). Majority 151(89.3%) were self-referred with two-wheel motorcycle being the commonest 46 (27.2%) mode of arrival to the hospital. Hypertensive emergency was found in over half 96 (56.8%) of the patients with hypertensive crisis, with oral medications administered in more than half of them, 71 (74%) as means to control the high blood pressure, and one-third 33 (34.4%) were discharged home. On multivariate analysis increasing age (AOR 4.53, p < 0.001), use of illicit drug (AOR 4.14, p-0.04) and pre-existing hypertension (AOR 8.1, p < 0.001) were independent risk factors for hypertensive crisis occurrence. Conclusion Hypertensive crisis among adult patients attending district and regional hospitals is common (63 patients per every 1000 patients). Increasing age, use of illicit drug and pre-existing hypertension are independent associated factors for developing hypertensive crisis.

DNA barcodes in Egyptian olive cultivars (Olea europaea L.) using the rbcL and matK coding sequences

Said Eglal M.,Hassan M. E. 한국작물학회 2023 Journal of crop science and biotechnology Vol.26 No.4

Olives (Olea europaea L.) are the most well-known trees of the Mediterranean basin. The genetic heritage of olive trees is very rich and characterized by an abundance of varieties, eventually leading to significant genotype mixing. Therefore, the classification and analysis of the genetic diversity of olive cultivars are challenges of high priority. It helps make more efficient use of the olive resources distributed globally and benefits the genetic improvement and breeding of olive varieties. DNA barcoding is a method for evaluating and classifying species that uses short, variable, and uniform DNA regions. This study used DNA sequencing data for the first time for DNA barcoding of Egyptian olive cultivars and assessed the genetic relationship between four local cultivars grown in Egypt and their relation to sequences within the database. PCR amplification and sequence characterization were used to assess the effectiveness of the two barcoding sites, rbcL and matK. Based on multiple alignments of all the sequences obtained from the analyzed regions, matK had the longest sequence (816 bp) and rbcL the shortest (411 bp) of the two barcoding loci. The matK gene region was the least varied, with a variability level of 77%, while the rbcL gene region had the highest amount of variability (98.7%). Because of the presence of unique variable sites, both barcoding loci rbcL and matK efficiencies discriminate the selective Egyptian olive cultivars. The DNA sequences from the individual and combined barcode loci were used in a maximum likelihood tree-based phylogenetic analysis to successfully distinguish the selected olive cultivars.

Selecting reservoir sites considering agricultural water demand and land use under CMIP5 climate change scenarios in Amo basin, Afghanistan

( Said Azim Sadat ),( Won-ho Nam ) 한국농공학회 2018 한국농공학회 학술대회초록집 Vol.2018 No.-

Considering the ongoing climate change and its effects in future on water resources, as it cannot be generated but preserved; selecting proper Dam/Reservoir site remains one of the crucial aspects of water resource management and reservoir construction. A proper site will not only provide the optimum results and benefits but it can also pave the way for generating hydropower, local businesses, and recreational areas. As so, a poor site will cause severe effects on the livelihood of locals and the environment. In this research, a look-ahead criterion was developed and implemented to include both quantitative and qualitative factors in locating potential sites for Dam/Reservoir in the study area. The Modified Penman-Monteith equation was used to determine reference evapotranspiration (ETo), while an MCDM (Multi-Criteria Decision Making) based Analytical Hierarchy Process (AHP) method was used to develop the Landuse map. The future projections were done based on 3 models from CMiP5 scenarios, the data was linearly scaled to remove the bias. A raster-based GIS analysis was implemented to include the criteria to produce the potential sites. The results indicated that the developed criteria were susceptible to environmental, physical and economic settings in the study area. Furthermore, this criterion can be manipulated in handling relevant data layers to produce the optimum outcome to provide management options for decision makers.

Implementation of Multilateral Environmental Agreements in Kazakhstan

Said Tulibayev 이준국제법연구원 2022 Journal of East Asia and International Law Vol.15 No.2

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.

The effects of five plant extracts on Brucella abortus 544 survivability in axenic culture condition and Brucella abortus 544 infection in RAW 264.7 macrophage cell line

Said Abdi Salad,Tran Xuan Ngoc Huy,Trang Thi Nguyen,Ched Nicole Turbela Aguilar,Suk Kim 한국예방수의학회 2023 한국예방수의학회 학술대회자료집 Vol.2023 No.-

Antecedents and Consequences of Employees Empowerment

Said Shaban Hamed KINFORMS 2010 Management Review Vol.5 No.1

This research examines the relationship between role clarity, organizational trust and employees empowerment , the relationship between employees empowerment and job involvement, job satisfaction. The research used a cross-sectional design. A random sample of 862 employees was selected to participate in this research. Self-administered questionnaires were used in data collection .The results show statistically significant positive relationships between role clarity , organizational trust and employees empowerment, and also a statistically significant positive relationships between employees empowerment and job involvement, job satisfaction. The article discusses implications of these findings.