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Clinico-pathological study and treatment results of 1009 operable breast cancer cases:Experience of NCI Cairo University,Egypt

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The Chinese-German Journal of Clinical Oncology 2010年第7期9卷 409-415页

作者： Magda el Mongy hesham el Hossieny Farouk Haggag Rania Fathy Department of Radiation Oncology National Cancer InstituteCairo University Department of Clinical Oncology Kasr El-Aini Centre Cairo University

Objective： This retrospective study was designed to evaluate ciinico-pathological data including stage, results of treatment, and prognostic factors which affect the overall survival ＆ disease free survival. Methods： This was a retrospective study carried out at the Radiotherapy Department, National Cancer Institute, Cairo University, Egypt on 1009 patients treated for primary breast cancer between 1999-2003. Results： The median follow-up was 68 months. Loco regional relapse occurred in 23 patients （2.3%） and distant relapse occurred in 203 patients （20.1%）. Both Ioco regional and distant relapse were reported in 32 patients （3.2%）. The disease free survival （DFS） at 3 and 5 years were 87% and 78% respectively, while OAS at 3 and 5 years were 96.4% and 91.4% respectively. Multivariate analysis of different prognostic factors showed that the independent bad prognostic factors in the study for disease relapse were positive lymph nodes （LNs, more than 10）, tumor size T3, T4 with significance of 0.0001 for each, and pathologic grade with significance of 0.003. Conclusion： The most important independent bad prognostic factors for relapse are positive LNs more than 10, tumor size T3, T4 and pathologic grade. The timing of radiotherapy affects the disease free survival significantly also it is recommended to analyze the group of patients with LNs negative using well designed randomized trials.

关键词： Clinico-pathological study breast cancer retrospective

Analysis of Different Call Admission Control Strategies and Its Impact on the Performance of LTE-Advanced Networks

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Communications and Network 2014年第2期6卷 137-154页

作者： Mahammad A. Safwat hesham M. el-Badawy Ahmad Yehya Hosni el-Motaafy Department of electrical Engineering Al-Azhar University Cairo Egypt Department of electronics and Computer Engineering HIT Tenth of Ramdan City Egypt Network Planning Department National Telecommunication Institute Cairo Egypt

The call admission control (CAC) optimizes the use of allocated channels against offered traffic maintaining the required quality of service (QoS). Provisioning QoS to user at cell-edge is a challenge where there is limitation in cell resources due to inter-cell interference (ICI). Soft Frequency Reuse is ICI mitigation scheme that controls the distribution of resources between users. In this paper, the Impact of four CAC schemes (Cutoff Priority scheme (CP), Uniform Fractional Guard Channel (UFGC), Limited Fractional Guard Channel (LFGC), New Call Bounding (NCB) scheme) at cell-edge have investigated using queuing analysis in a comparative manner. The comparison is based on two criteria. The first criterion guarantees a particular level of service to already admitted users while trying to optimize the revenue obtained. The second criterion determines the minimum of number of radio resources that provides hard constraints in both of blocking and dropping probabilities. The four schemes are compared at different scenarios of new and handover call arrival rates.

关键词： Call Admission Control Soft Frequency Reuse QoS

Performance of Analysis Cognitive Radio with Cooperative Sensing under Malicious Attacks over Nakagami Faded Channels

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Wireless Engineering and Technology 2016年第2期7卷 67-74页

作者： Hagar O. Shazly Asmaa Saafan hesham el Badawy Hadia M. el Hennawy Faculty of Engineering Ain Shams University Cairo Egypt National Telecommunication Institute (NTI) Cairo Egypt

The different realistic propagation channels are faced frequently the multipath fading environments. The main goal of this system design (cognitive radio network) is to improve the efficiency of spectrum access on a non-interfering basis. This system achieves high utilization for the limited spectrum in order to fulfill needs for all users’ demands which are considered as a problem in wireless communications due to rapidly increasing in wireless applications and service. This system is exposed to attack due to the vulnerabilities existence in this system. So, the main outcome of this paper is to investigate the performance of the cooperative sensing in cognitive radio networks under malicious attacks over different channel impairments, and to illustrate the most suitable individual probability of detection in real faded channel by using Nakagami model. This paper illustrates the effectiveness of the attacks and fading on the performance of spectrum sensing process.

关键词： Cognitive Radio Cooperative Sensing Malicious Attacks Nakagami Faded Channels

Performance Assessment for LTE-Advanced Networks with Uniform Fractional Guard Channel over Soft Frequency Reuse Scheme

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Wireless Engineering and Technology 2013年第4期4卷 161-170页

作者： Mahammad A. Safwat hesham M. el-Badawy Ahmad Yehya Hosni el-Motaafy Department of electrical Engineering Alazhar University Cairo Egypt Department of electronics and Computer Engineering HIT Egypt Network Planning Department National Telecommunication Institute Cairo Egypt

Dropping probability of handoff calls and blocking probability of new calls are two important Quality of Service (QoS) measures for LTE-Advanced networks. Applying QoS for Cell edge users in soft frequency reuse scheme in LTE system is a challenge as they already suffer from limited resources. Assigning some resources for handover calls may enhance dropping probability but this is in price of degradation in the blocking probability for new calls in cell-edge. Uniform Fractional Guard Channel (UFGC) is a call admission policy that provides QoS without reserving resources for handover calls. In this paper, the performance of Soft Frequency Reuse (SFR) in presence of Uniform Fractional Guard Channel (UFGC) will be investigated using queuing analysis. The mathematical model and performance metrics will be deduced in this assessment. The impact of UFGC will be evaluated in edge and core part separately. Then the optimal value for the parameter of UFGC will be obtained to minimize the blocking probability of new calls with the constraint on the upper bound on the dropping probability of handoff calls.

关键词： Soft Frequency Reuse Queuing Uniform Fractional Guard Channel

Novel Optimized Cross-Layer Design with Maximum Weighted Capacity Based Resource Allocation for AMC/HARQ Wireless Networks

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Wireless Engineering and Technology 2013年第2期4卷 77-86页

作者： Reham A. el-Mayet hesham M. el-Badawy Salwa H. elramly electronic and Communication Department Ain Shams University Cairo Egypt National Telecommunication Institute Cairo Egypt

To provide quality-of service (QoS) guarantees for heterogeneous applications, most recent wireless communications technologies and standards combine the error-correcting capability of hybrid automatic repeat request (HARQ) schemes at the data link layer (DLL) with the adaptation ability of the adaptive modulation and coding (AMC) modes at the physical layer (PHY) layer. This paper aims to investigate the aggregated system capacity as well as the breakdown of this capacity for different ACM modes in each HARQ scheme. This investigation was done by using maximum weighted capacity (MWC) resource allocation at the PHY layer in conjunction with a novel packet error rate (PER)-based scheduling at the medium access control (MAC) layer. As a result, the dominant AMC mode corresponding to channel SNR was available.

关键词： AMC Cross-Layer Design HARQ Nakagami-m Fading Channel QoS

Attacks on Anonymization-Based Privacy-Preserving: A Survey for Data Mining and Data Publishing

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Journal of Information Security 2013年第2期4卷 101-112页

作者： Abou-el-ela Abdou Hussien Nermin Hamza hesham A. Hefny Department of Computer and Information Sciences Institute of Statistical Studies and Research Cairo University Giza Egypt Department of Computer Science Faculty of Science and Humanities Shaqra University Shaqra KSA

Data mining is the extraction of vast interesting patterns or knowledge from huge amount of data. The initial idea of privacy-preserving data mining PPDM was to extend traditional data mining techniques to work with the data modified to mask sensitive information. The key issues were how to modify the data and how to recover the data mining result from the modified data. Privacy-preserving data mining considers the problem of running data mining algorithms on confidential data that is not supposed to be revealed even to the party running the algorithm. In contrast, privacy-preserving data publishing (PPDP) may not necessarily be tied to a specific data mining task, and the data mining task may be unknown at the time of data publishing. PPDP studies how to transform raw data into a version that is immunized against privacy attacks but that still supports effective data mining tasks. Privacy-preserving for both data mining (PPDM) and data publishing (PPDP) has become increasingly popular because it allows sharing of privacy sensitive data for analysis purposes. One well studied approach is the k-anonymity model [1] which in turn led to other models such as confidence bounding, l-diversity, t-closeness, (α,k)-anonymity, etc. In particular, all known mechanisms try to minimize information loss and such an attempt provides a loophole for attacks. The aim of this paper is to present a survey for most of the common attacks techniques for anonymization-based PPDM & PPDP and explain their effects on Data Privacy.

关键词： Privacy k-Anonymity Data Mining Privacy-Preserving Data Publishing Privacy-Preserving Data Mining

A Modified Cold Molybdenum Cathode Penning Ion Source

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Journal of Physical Science and Application 2013年第4期3卷 229-237页

作者： Adel Gomah Helal hesham el-Khabeary Tawfik Samah Ibrihem Radwan Accelerators & Ion Sources Department Basic Nuclear Science Division Nuclear Research Center Atomic Energy AuthorityP.N. 13759 Cairo Egypt

In this paper, design and construction of a modified cold molybdenum cathode Penning ion source was described. It consists of copper cylindrical anode with two cone ends and two movable cold molybdenum cathodes. The two cathodes were placed symmetrically at two ends of the anode. The modifications were decrease the length of the cylindrical anode to 4 cm instead of 6 cm, transform the copper emission electrode shape from plate of 40 mm length, 25 mm width and 2 mm thickness to disc of 20 mm diameter and 2 mm thickness and transform the inner uncovered area of the emission electrode from slit of 30 mm length and 10 mm width to disc of 5 mm diameter. The copper emission electrode was placed in the middle of the cylindrical anode and has aperture in the center of different diameters. Faraday cup was placed at different distances from the emission electrode aperture. The electrical discharge and the output ion beam characteristics of the modified ion source were measured at different pressures using argon gas. It was found that the optimum operating conditions of the modified ion source are; anode-cathode distance equal to 6 mm, emission electrode aperture diameter equal to 2.5 mm and emission electrode aperture, Faraday cup distance equals 3 cm. The effect of axial samarium cobalt permanent magnet of intensity equal to 300 Gauss on the discharge characteristics of the ion source was determined.

关键词： Penning ion source cold molybdenum cathode samarium cobalt permanent magnet.

Foliar Application of Phosphorus Enhances Photosynthesis and Biochemical Characteristics of Maize under Drought Stress

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Phyton-International Journal of Experimental Botany 2021年第2期90卷 503-514页

作者： Zahoor Ahmad Ejaz Ahmad Waraich Muhammad Zia ur Rehman Muhammad Ashar Ayub Muhammad Usman hesham Alharby Atif Bamagoos Celaleddin Barutçular Muhammad Ali Raza FatihÇiğ Ayman el Sabagh Department of Field Crops Faculty of AgricultureÇukurova UniversityAdana01330Turkey Department of Botany University of Central Punjab(UCP)Punjab Group of CollegesBahawalpur63100Pakistan Department of Agronomy University of AgricultureFaisalabad38000Pakistan Institute of Soil and Environmental Science University of AgricultureFaisalabad38000Pakistan Department of Biological Sciences Faculty of ScienceKing Abdulaziz UniversityJeddah21577Saudi Arabia College of Agronomy Sichuan Agricultural UniversityChengdu611130China Department of Field Crops Faculty of AgricultureSiirt UniversitySiirt56100Turkey Department of Agronomy Faculty of AgricultureUniversity of KafrelsheikhKafrelsheikh33516Egypt

Water is essential for the growth period of crops;however,water unavailability badly affects the growth and physiological attributes of crops,which considerably reduced the yield and yield components in ***,a pot experiment was conducted to investigate the effect of foliar phosphorus(P)on morphological,gas exchange,biochemical traits,and phosphorus use efficiency(PUE)of maize(Zea mays L.)hybrids grown under normal as well as water deficit situations at the Department of Agronomy,University of Agriculture Faisalabad,Pakistan in *** different treatments(control and P@8 kg ha^(−1))and four hybrids(Hycorn,31P41,65625,and 32B33)of maize were tested by using a randomized complete block design(RCBD)with three *** showed that the water stress caused a remarkable decline in total soluble protein(9.7%),photosynthetic rate(9.4%)and transpiration rate(13.4%),stomatal conductance(10.2%),and internal CO_(2)rate(20.4%)comparative to well-watered *** increase of 37.1%,36.8%,and 24.5%were recorded for proline,total soluble sugar,and total free amino acid,***,foliar P application minimized the negative impact of drought by improving plant growth,physio-biochemical attributes,and PUE in maize plants under water stress *** the hybrids tested,the hybrid 6525 performed better both under stress and non-stress *** outcomes confirmed that the exogenous application of P improved drought stress tolerance by modulating growth,physio-biochemical attributes,and PUE of maize hybrids.

关键词： Photosynthetic attributes biochemical characters water stress foliar P Maize

Utility-Based Anonymization Using Generalization Boundaries to Protect Sensitive Attributes

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Journal of Information Security 2015年第3期6卷 179-196页

作者： Abou-el-ela Abdou Hussien Nagy Ramadan Darwish hesham A. Hefny Department of Computer Science Faculty of Science and Arts Shaqra University Shaqra KSA Department of Computer and Information Sciences Institute of Statistical Studies and Research Cairo University Cairo Egypt

Privacy preserving data mining (PPDM) has become more and more important because it allows sharing of privacy sensitive data for analytical purposes. A big number of privacy techniques were developed most of which used the k-anonymity property which have many shortcomings, so other privacy techniques were introduced (l-diversity, p-sensitive k-anonymity, (α, k)-anonymity, t-closeness, etc.). While they are different in their methods and quality of their results, they all focus first on masking the data, and then protecting the quality of the data. This paper is concerned with providing an enhanced privacy technique that combines some anonymity techniques to maintain both privacy and data utility by considering the sensitivity values of attributes in queries using sensitivity weights which determine taking in account utility-based anonymization and then only queries having sensitive attributes whose values exceed threshold are to be changed using generalization boundaries. The threshold value is calculated depending on the different weights assigned to individual attributes which take into account the utility of each attribute and those particular attributes whose total weights exceed the threshold values is changed using generalization boundaries and the other queries can be directly published. Experiment results using UT dallas anonymization toolbox on real data set adult database from the UC machine learning repository show that although the proposed technique preserves privacy, it also can maintain the utility of the publishing data.

关键词： Privacy Privacy Preserving Data Mining K-Anonymity Generalization Boundaries Suppression