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subgroup Discovery Algorithms： A survey and Empirical Evaluation

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Journal of Computer science & Technology 2016年第3期31卷 561-576页

作者： sumyea helal school of Information Technology and Mathematical sciences University of South Australia Adelaide SA5001 Australia

subgroup discovery is a data mining technique that discovers interesting associations among different variables with respect to a property of interest. Existing subgroup discovery methods employ different strategies for searching, pruning and ranking subgroups. It is very crucial to learn which features of a subgroup discovery algorithm should be considered for generating quality subgroups. In this regard, a number of reviews have been conducted on subgroup discovery. Although they provide a broad overview on some popular subgroup discovery methods, they employ few datasets and measures for subgroup evaluation. In the light of the existing measures, the subgroups cannot be appraised from all perspectives. Our work performs an extensive analysis on some popular subgroup discovery methods by using a wide range of datasets and by defining new measures for subgroup evaluation. The analysis result will help with understanding the major subgroup discovery methods, uncovering the gaps for further improvement and selecting the suitable category of algorithms for specific application domains.

关键词： subgroup discovery searching pruning measure evaluation

electrodeposited Ni and Ni-Co alloys using cysteine and conventional ultrasound waves

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science China Chemistry 2013年第10期56卷 1446-1454页

作者： el-FEKY Hesham NEGEM Mosaad ROY sudipta helal Nadia BARAKA A. Chemistry Department Faculty of Science Fayoum UniversityFayoum 63514 Egypt school of Chemical Engineering and Advanced Materials Newcastle University Newcastle upon TyneNE1 7RU United Kingdom Chemistry Department Faculty of Science Cairo UniversityGiza 12613 Egypt

Ni-Co alloys were electroplated from sulphate electrolyte using addition agents including sodium gluconate, boric acid and eysteine on copper foil by the galvanostatic technique and ultrasound waves. The chemical composition, surface morphologies, crystalline structure and hardness of the Ni-Co alloys were studied using energy dispersive spectroscopy, scanning electron microscope, X-ray diffraction and Vickers testing method, respectively. The effect of current density and addition agents on the microstructure and morphology of Ni-Co alloys were examined. The appropriate concentration of additives and ultrasound waves were found to produce fine and smooth crystals leading to higher hardness of Ni-Co alloys. The microhardness of the Ni-Co alloys was varied between 4860-7530 HV. The surface morphology of coatings was changed from granular to fine due to using of gluconate, boric acid, cysteine and ultrasound waves. The mechanical properties of nanocrystalline Ni-Co alloys showed an increase of the hardness with the growing of Ni content in the alloy. The X-ray diffraction studies indicated that nanocrystalline structure was face-centred cubic for pure Ni and Ni-Co alloys with Co content in the range of 1-75 wt.%. A hexagonal closed-package structure was obtained for pure Co and Ni-Co alloys with the cobalt content with range of 75-99 wt.%.

关键词： electrodeposition nanocrystalline Ni alloys ultrasound microhardness

Applications of Amplitude versus Offset and seismic Attributes for Perceiving Messinian Reservoirs in Nidoco Field, Nile Delta, Egypt

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International Journal of Geosciences 2022年第5期13卷 319-328页

作者： Ahmed abu el-saoud Abd el-Nasser helal Justin Matresu Amir M. s. Lala Belayim Petroleum Company (Petrobel) Cairo Egypt Faculty of science Ain Shams University Cairo Egypt Exploration Team Leader at Eni Cairo Egypt

Nile Delta which covers approximately 60,000 square kilometers represents the most important gas province in Egypt whereas its fields provide two-thirds of the gas production in Egypt. The Nile Delta province begins to display its hydrocarbon potentiality in the early 1960s. Nidoco field is located in the shallow water offshore Nile delta. abu Madi formation (Messinian age) is the most important formation through all the section where it represents the main gas producing reservoirs in the Field. The production of the field is coming from two sand reservoir levels;abu Madi level 2&3 which are characterized by fluvial-deltaic sandstones. The purpose of this paper is to perceive the Messinian gas bearing reservoirs and channelized sand distribution inside abu Madi formation using seismic attributes and amplitude versus offset (AVO) technique. The results indicated that the seismic attributes and AVO aided to give a complete picture about the Messinian reservoirs distribution and characterization in the field. Also the results show that there are still promising locations of prospective abu Madi Level 2&3 which are proposed to be drilled in the field.

关键词： AVO Nidoco Field abu Madi Formation seismic Attributes

Voltage imbalance mitigation in an active distribution network using decentralized current control

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Protection and Control of Modern Power systems 2023年第2期8卷 68-84页

作者： Ahmed M.M.Nour Ahmed A.helal Magdi M.el-saadawi Ahmed Y.Hatata Alexandria Higher Institute of Engineering and Technology(AIET) AlexandriaEgypt Department of electrical and Control Engineering Arab Academy for Science and Technology and Maritime TransportAlexandriaEgypt Department of electrical Engineering Faculty of EngineeringMansoura UniversityMansouraEgypt Department of electrical Engineering College of EngineeringShaqra UniversityShaqraKingdom of Saudi Arabia

Voltage imbalance(VI)is caused by the difference in connected single-phase load or generation in a low voltage distribution network(DN).VI increase in a smart distribution grid is due to the current practice of increasing single-phase distributed generators such as photovoltaic(PV)*** paper proposes a decentralized control method to mitigate VI using distributed batteries included in smart grid interfaced residential PV *** mitigate VI using the batteries in this way,five challenges must be overcome,i.e.,equalizing all battery stress currents within the DN,mitigating VI in abnormal conditions such as signal loss among bus controllers,being immune from the distorted feedback measurements,minimizing the steady-state error at different loads,and overcoming the insufficient number or capacity of the distributed batteries at the same *** fuzzy logic controllers(FLC)are proposed at each bus to overcome these five tasks based on a decentralized control *** proposed decentralized control based on FLC is compared with centralized control based on a PI *** proposed control method is tested and verified using simulations in the MATLAB/simulink software,and the results validate the ability of the scheme to alleviate VI on a smart distribution network under both normal and abnormal conditions.

关键词： Fuzzy controller Distributed batteries Decentralized control Voltage imbalance Distributed PV

Lymphocytic colitis: A clue to bacterial etiology

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World Journal of Gastroenterology 2005年第46期11卷 7266-7271页

作者： Thanaa EA helal Naglaa s Ahmed Osama Abo el Fotoh Department of PathologyFaculty of Medicine Ain Shams UniversityEgypt Department of Internal MedicineFaculty of Medicine Ain Shams UniversityEgypt

AIM： To find out the role of bacteria as a possible etiological factor in lymphocytic colitis. METHODs： Twenty patients with histopathological diagnosis of lymphocytic colitis and 10 normal controls were included in this study. Colonoscopic biopsies were obtained from three sites （hepatic and splenic flexures and rectosigmoid region）. Each biopsy was divided into two parts. A fresh part was incubated on special cultures for bacterial growth. The other part was used for the preparation of histologic tissue sections that were examined for the presence of bacteria with the help of Giemsa stain. REsULTs： Culture of tissue biopsies revealed bacterial growth in 18 out of 20 patients with lymphocytic colitis mostly Escherichia coil （14/18）, which was found in all rectosigmoid specimens （14/14）, but only in 8/14 and 6/14 of splenic and hepatic flexure specimens respectively. In two of these cases, E coli was associated with proteus. Proteus was found only in one case, Klebsiella in two cases, and staphylococcus aureus in one case. In the control group, only 2 out of 10 controls showed the growth of E coli in their biopsy cultures. Histopathology showed rod-shaped bacilli in the tissue sections of 12 out of 14 cases with positive E coli in their specimen＇s culture. None of the controls showed these bacteria in histopathological sections. CONCLUsION： This preliminary study reports an association between E coli and lymphocytic colitis, based on histological and culture observations. serotyping and molecular studies are in process to assess the role of E coli in the pathogenesis of lymphocytic colitis.

关键词： Lymphocytic colitis E coli Histopathology Culture

Dark Energy Explained via the Hawking-Hartle Quantum Wave and the Topology of Cosmic Crystallography

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International Journal of Astronomy and Astrophysics 2013年第3期3卷 318-343页

作者： Mohamed s. el Naschie Atef helal Department of Mathematics University of Cairo Cairo Egypt Department of Physics University of Alexandria Alexandria Egypt

The aim of the present paper is to explain and accurately calculate the missing dark energy density of the cosmos by scaling the Planck scale and using the methodology of the relatively novel discipline of cosmic crystallography and Hawking-Hartle quantum wave solution of Wheeler-DeWitt equation. Following this road we arrive at a modified version of Einstein’s energy mass relation E = mc2 which predicts a cosmological energy density in astonishing accord with the WMAP and supernova measurements and analysis. We develop non-constructively what may be termed super symmetric Penrose fractal tiling and find that the isomorphic length of this tiling is equal to the self affinity radius of a universe which resembles an 11 dimensional Hilbert cube or a fractal M-theory with a Hausdorff dimension where. It then turns out that the correct maximal quantum relativity energy-mass equation for intergalactic scales is a simple relativistic scaling, in the sense of Weyl-Nottale, of Einstein’s classical equation, namely EQR = (1/2)(1/) moc2 = 0.0450849 mc2 and that this energy is the ordinary measurable energy density of the quantum particle. This means that almost 95.5% of the energy of the cosmos is dark energy which by quantum particle-wave duality is the absolute value of the energy of the quantum wave and is proportional to the square of the curvature of the curled dimension of spacetime namely where and is Hardy’s probability of quantum entanglement. Because of the quantum wave collapse on measurement this energy cannot be measured using our current technologies. The same result is obtained by involving all the 17 stein spaces corresponding to 17 types of the wallpaper groups as well as the 230-11=219 three dimensional crystallographic group which gives the number of the first level of massless particle-like states in Heterotic string theory. All these diverse subjects find here a unified view point leading to the same result regarding the missing dark energy of the universe

关键词： Doubly special Relativity Week’s Manifold Experimental Test of Einstein’s Relativity Witten’s M-Theory Ordinary Energy of the Quantum Particle Hawking-Hartle Wave of Cosmos Crystallographic symmetry Groups Revising special Relativity

Propagation of electromagnetic Waves in slab Waveguide structure Consisting of Chiral Nihility Claddings and Negative-Index Material Core Layer

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Photonic sensors 2018年第2期8卷 176-187页

作者： Alaa N. abu helal sofyan A. TAYA Khitam Y. elWAsIFE Physics Department Islamic University of Gaza Gaza 108 Palestine

The dispersion equation of an asymmetric three-layer slab waveguide, in which all layers are chiral materials is presented. Then, the dispersion equation of a symmetric slab waveguide, in which the claddings are chiral materials and the core layer is negative index material, is derived. Normalized cut-off frequencies, field profile, and energies flow of right-handed and left-handed circularly polarized modes are derived and plotted. We consider both odd and even guided modes. Numerical results of guided low-order modes are provided. some novel features, such as abnormal dispersion curves, are found.

关键词： slab waveguides chiral materials left-handed materials

A new approach for fuel injection into a solar receiver/ reactor:Numerical and experimental investigation

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Frontiers of Chemical science and Engineering 2018年第4期12卷 683-696页

作者： M helal Uddin Nesrin Ozalp Jens Heylen Cedric Ophoff Mechanical and Industrial Engineering Department University of Minnesota DuluthDuluthMN 55812-3042USA Mechanical Engineering Department 3001 LeuvenBelgium

An innovative and efficient design of solar receivers/reactors can enhance the production of clean fuels via concentrated solar energy. This study presents a new jet-type burner nozzle for gaseous feedstock injection into a cavity solar receiver inspired from the combustion technology. The nozzle design was adapted from a combustion burner and successfully implemented into a solar receiver and studied the influence of the nozzle design on the fluid mixing and temperature distribution inside the solar receiver using a 7 kW solar simulator and nitrogen as working fluid. Finally, a thorough computational fluid dynamics (CFD) analysis was performed and validated against the experimental results. The CFD results showed a variation of the gas flow pattern and gas mixing after the burner nozzle adaptation, which resulted an intense effect on the heat transfer inside the solar receiver.

关键词： solar reactor nozzle CFD heat transfer mixing and recirculation

Biological and molecular studies on specific immune cells treated with checkpoint inhibitors for the thera-personal approach of breast cancer patients(ex-vivo study)

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Oncology Research 2021年第5期29卷 319-330页

作者： MOTAWA E.el-HOUsEINI MOsTAFA s.ARAFAT AHMED M.el-HUssEINY IsLAM M.KAsEM MAHMOUD M.KAMel AHMED H.el-HABAsHY MEDHAT M.KHAFAGY ENAs M.RADWAN MAHA H.helal MONA s.ABDelLATEIF Medical Biochemistry and Molecular Biology Cancer Biology DepartmentNational Cancer InstituteCairo UniversityCairo11976Egypt Biotechnology Department Faculty of ScienceCairo UniversityGiza12613Egypt Zoology department Faculty of ScienceCairo UniversityGiza12613Egypt Clinical Pathology Department National Cancer InstituteCairo UniversityCairo11976Egypt Department of Pathology National Cancer InstituteCairo UniversityCairo11976Egypt surgical Oncology Department National Cancer InstituteCairo UniversityCairo11976Egypt Radio-Diagnosis Department National Cancer InstituteCairo UniversityCairo11976Egypt

Immunotherapy becomes a promising line of treatment for breast cancer(BC)however,its success rate is still ***:The study was designed to optimize the condition for producing an effective dendritic cell(DCs)based immunotherapy by using DCs and T lymphocytes together with tumor-inﬁltrating lymphocytes(TILs)and tumor-inﬁltrating DCs(TIDCs),treated with anti-PD1 and anti-CTLA4 monoclonal *** mixture of immune cells was co-cultured with autologous breast cancer cells(BCCs)isolated from 26 BC ***:There was a signiﬁcant upregulation of CD86 and CD83 on DCs(p=0.001 and 0.017,respectively),similarly upregulation of CD8,CD4 and CD103 on T cells(p=0.031,0.027,and 0.011,respectively).While there was a signiﬁcant downregulation of FOXP3 and combined ***8 expression on regulatory T cells(p=0.014 for both).Increased CD8/Foxp3 ratio(ps also ***133,CD34 and CD44 were downregulated on BCCs(p=0.01,0.021,and 0.015,respectively).There was a signiﬁcant increase in interferon-γ(IFN-γ,pse(LDH,p=0.02),and a signiﬁcant decrease in vascular endothelial growth factor(VEGF,pssion of FOXP3 and Programmed cell death ligand 1(PDL-1)were downregulated in BCCs(psimilarly cytotoxic T lymphocyte antigen-4(CTLA4,p=0.02),Programmed cell death 1(PD-1,psigniﬁcantly downregulated in T ***:Ex-vivo activation of immune cells(DCs,T cells,TIDCs,and TILs)with immune checkpoint inhibitors could produce a potent and effective BC ***,these data should be validated on an experimental animal model to be transferred to the clinical setting.

关键词： Immunotherapy breast cancer PD1 CTLA4 TIDCs TILs