On Fuzzy Subspaces

A. M. Zahran KYUNGPOOK UNIVERSITY 2001 Kyungpook mathematical journal Vol.41 No.2

In 1993, M. Macho Stadler and M.A. Prada Vicente have introduced a new concept of fuzzy topological subspace over from the fuzzy topology δ, which coincides with the usual definition in the case that μ = χ_(y), Y ⊂ X. Also, them gave characterization for some fuzzy topological concepts in this sense. In this paper we introduce some concepts such as q-nbd systems, separation axioms, continuity, almost continuity, compactness and connectedness in this sense.

Phytotherapeutic effects of Echinacea purpurea in gamma-irradiated mice

Yasser E. Shahein,Amira M. K. Abouelella,Sameh S. Tawfik,Ahmed M. Zahran1 대한수의학회 2007 Journal of Veterinary Science Vol.8 No.4

Echinacea (E.) purpurea herb is commonly known as the purple coneflower, red sunflower and rudbeckia. In this paper, we report the curative efficacy of an Echinacea extract in γ-irradiated mice. E. purpurea was given to male mice that were divided into five groups (control, treated, irradiated, treated before irradiation & treated after irradiation) at a dose of 30 mg/kg body weight for 2 weeks before and after irradiation with 3 Gy of γ-rays. The results reflected the detrimental reduction effects of γ-rays on peripheral blood hemoglobin and the levels of red blood cells, differential white blood cells, and bone marrow cells. The thiobarbituric acid-reactive substances (TBARs) level, Superoxide dismutase (SOD) and glutathione peroxidase (GSPx) activities and DNA fragmentation were also investigated. FT-Raman spectroscopy was used to explore the structural changes in liver tissues. Significant changes were observed in the microenvironment of the major constituents, including tyrosine and protein secondary structures. E. purpurea administration significantly ameliorated all estimated parameters. The radio-protection effectiveness was similar to the radio-recovery curativeness in comparison to the control group in most of the tested parameters. The radio-protection efficiency was greater than the radio-recovery in hemoglobin level during the first two weeks, in lymphoid cell count and TBARs level at the fourth week and in SOD activity during the first two weeks, as compared to the levels of these parameters in the control group

Low Cost Alcoholic Breath Sensor Based on SnO2 Modified with CNTs and Graphene

M. Morsy,I. S. Yahia,H. Y. Zahran,M. Ibrahim 한국물리학회 2018 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.73 No.10

In this work, SnO2 modified with reduced graphene oxide (rGO) and carbon nanotubes (CNTs) separately and combined sensitized by using the co-precipitation method and their sensing behavior toward ethanol vapor at room temperature were investigated. An interdigitated electrode (IDE) gold substrate is very expensive compared to a uorine doped tin oxide (FTO) substrate; hence, we used the latter to reduce the fabrication cost. The structure and the morphology of the studied materials were characterized by using differential thermal analyses (DTA) and thermogravimetric analysis (TGA), transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Brunauer-Emmett-Teller surface area and Barrett-Joyner- Halenda (BJH) pore size measurements. The studied composites were subjected to ethanol in its gas phase at concentrations from 10 to 200 ppm. The present composites showed high-performance sensitivity for many reasons: the incorporation of SnO2 and CNTs which prevents the agglomeration of rGO sheets, the formation of a 3D mesopourus structure and an increase in the surface area. The decoration with rGO and CNTs led to more active sites, such as vacancies, which increased the adsorption of ethanol gas. In addition, the mesopore structure and the nano size of the SnO2 particles allowed an ecient diffusion of gases to the active sites. Based on these results, the present composites should be considered as ecient and low-cost sensors for alcohol.

Assessment of Earth Remote Sensing Microsatellite Power Subsystem Capability during Detumbling and Nominal Modes

Zahran M.,Okasha M.,Ivanova Galina A. The Korean Institute of Power Electronics 2006 JOURNAL OF POWER ELECTRONICS Vol.6 No.1

The Electric Power Subsystem (EPS) is one of the most critical systems on any satellite because nearly every subsystem requires power. This makes the choice of power systems the most important task facing satellite designers. The main purpose of the Satellite EPS is to provide continuous, regulated and conditioned power to all the satellite subsystems. It has to withstand radiation, thermal cycling and vacuums in hostile space environments, as well as subsystem degradation over time. The EPS power characteristics are determined by both the parameters of the system itself and by the satellite orbit. After satellite separation from the launch vehicle (LV) to its orbit, in almost all situations, the satellite subsystems (attitude determination and control, communication and onboard computer and data handling (OBC&DH)), take their needed power from a storage battery (SB) and solar arrays (SA) besides the consumed power in the EPS management device. At this point (separation point, detumbling mode), the satellite's angular motion is high and the orientation of the solar arrays, with respect to the Sun, will change in a non-uniform way, so the amount of power generated by the solar arrays will be affected. The objective of this research is to select satellite EPS component types, to estimate solar array illumination parameters and to determine the efficiency of solar arrays during both detumbling and normal operation modes.

Assessment of Earth Remote Sensing Microsatellite Power Subsystem Capability during Detumbling and Nominal Modes

M. Zahran,M. Okasha,Galina A. Ivanova 전력전자학회 2006 JOURNAL OF POWER ELECTRONICS Vol.6 No.1

The Electric Power Subsystem (EPS) is one of the most critical systems on any satellite because nearly every subsystem requires power. This makes the choice of power systems the most important task facing satellite designers. The main purpose of the Satellite EPS is to provide continuous, regulated and conditioned power to all the satellite subsystems. It has to withstand radiation, thermal cycling and vacuums in hostile space environments, as well as subsystem degradation over time [1]. The EPS power characteristics are determined by both the parameters of the system itself and by the satellite orbit [2]. After satellite separation from the launch vehicle (LV) to its orbit, in almost all situations, the satellite subsystems (attitude determination and control, communication and onboard computer and data handling (OBC&DH)), take their needed power from a storage battery (SB) and solar arrays (SA) besides the consumed power in the EPS management device. At this point (separation point, detumbling mode), the satellite's angular motion is high and the orientation of the solar arrays, with respect to the Sun, will change in a non-uniform way, so the amount of power generated by the solar arrays will be affected.<br/> The objective of this research is to select satellite EPS component types, to estimate solar array illumination parameters and to determine the efficiency of solar arrays during both detumbling and normal operation modes.

L.E.O. Satellite Power Subsystem Reliability Analysis

M. Zahran,S. Tawfik,Gennady Dyakov 전력전자학회 2006 JOURNAL OF POWER ELECTRONICS Vol.6 No.2

Satellites have provided the impetus for the orderly development of reliability engineering research and analysis because they tend to have complex systems and hence acute problems. They were instrumental in developing mathematical models for reliability, as well as design techniques to permit quantitative specification, prediction and measurement of reliability. Reliability engineering is based on implementing measures which insure an item will perform its mission successfully. The discipline of reliability engineering consists of two fundamental aspects; (1<SUP>st</SUP>) paying attention to details, and (2<SUP>nd</SUP>) handling uncertainties. This paper uses some of the basic concepts, formulas and examples of reliability theory in application.<br/> This paper emphasizes the practical reliability analysis of a Low Earth Orbit (LEO) Micro-satellite power subsystem. Approaches for specifying and allocating the reliability of each element of the power system so as to meet the overall power system reliability requirements, as well as to give detailed modeling and predicting of equipment/system reliability are introduced. The results are handled and analyzed to form the final reliability results for the satellite power system. The results show that the Electric Power Subsystem (EPS) reliability meets the requirements with quad microcontrollers (MC), two boards working as main and cold redundant while each board contains two MCs in a hot redundant.

Real-Time Implementation of On-Line Trained Neuro-Controller For a BLDC Motor

M.M.Salem,M.B.Zahran,Yousry Atia,A.M.Zaki 전력전자학회 2003 JOURNAL OF POWER ELECTRONICS Vol.3 No.1

Implementation and experimental verification of a simple neuro-controller (SNC) as a speed controller for a brush less DC (BLDC) motor is presented The SNC with one weight and a linear hard limit activation function is trained on-line using the back propagation algorithm. A modified error function is used to ensure good performance during the on-line training, which has been used without previous off-line training. The SNC has been Implemented using a computer-interface card mounted on a PC The driving system performance has been investigated by a number of experimental tests for a variety of input reference speed trajectories.<br/>

Decomposition of fuzzy ideal continuity via fuzzy idealization

Zahran, Ahmed M.,El-Baki, S. Ahmed Abd,Saber, Yaser Mohammed Korean Institute of Intelligent Systems 2009 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.9 No.2

Recently, El-Naschie has shown that the notion of fuzzy topology may be relevant to quantum paretical physics in connection with string theory and E-infinity space time theory. In this paper, we study the concepts of r-fuzzy semi-I-open, r-fuzzy pre-I-open, r-fuzzy $\alpha$-I-open and r-fuzzy $\beta$-I-open sets, which is properly placed between r-fuzzy openness and r-fuzzy $\alpha$-I-openness (r-fuzzy pre-I-openness) sets regardless the fuzzy ideal topological space in Sostak sense. Moreover, we give a decomposition of fuzzy continuity, fuzzy ideal continuity and fuzzy ideal $\alpha$-continuity, and obtain several characterization and some properties of these functions. Also, we investigate their relationship with other types of function.

An (r,s)-derived sets and double fuzzy closure operators

Zahran, Ahmed M.,Abd-Allah, M. Azab,EI-Saady, Kamal,EI-Rahman, Abd EI-Nasser G. Abd Korean Institute of Intelligent Systems 2008 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.8 No.1

In this paper, we introduce the concept of fuzzy (r, s)-adherence points, fuzzy (r, s)-accumulation points and fuzzy (r, s)-derived sets in double fuzzy topology. We investigate some of their properties. The relationship with double fuzzy closure operator was studied.

On Fuzzifying Nearly Compact Spaces

Zahran, A.M.,Sayed, O.R.,Abd-Allah, M. Azab,Mousa, A.K. Korean Institute of Intelligent Systems 2010 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.10 No.4

This paper considers fuzzifying topologies, a special case of I-fuzzy topologies (bifuzzy topologies) introduced by Ying [16, (I)]. It investigates topological notions defined by means of regular open sets when these are planted into the frame-work of Ying's fuzzifying topological spaces (in ${\L}$ukasiewwicz fuzzy logic). The concept of fuzzifying nearly compact spaces is introduced and some of its properties are obtained. We use the finite intersection property to give a characterization of fuzzifying nearly compact spaces. Furthermore, we study the image of fuzzifying nearly compact spaces under fuzzifying completely continuous functions, fuzzifying almost continuity and fuzzifying R-map.