OALib Journal期刊

ISSN: 2333-9721




2018 ( 24 )

2017 ( 715 )

2016 ( 1073 )

2015 ( 14269 )


匹配条件: “ Abbass A. Hashim” ,找到相关结果约460778条。
Flame Retardancy Enhancement of Hybrid Composite Material by Using Inorganic Retardants  [PDF]
Mohammed Al-Maamori, A Al-Mosawi, Abbass Hashim
Materials Sciences and Applications (MSA) , 2011, DOI: 10.4236/msa.2011.28153
Abstract: This study aims to investigate the possibility of improving the flame Retardancy for the hybrid composite material consisting araldite resin (CY223). The hybrid composite was reinforced by hybrid fibers from carbon and Kevlar fibers on woven roving form (45o -0o), by using a surface layer of 4mm thick of Zinc Borate flame retardant. Afterward, the structure was exposed directly to gas flame of 2000oC due to 10 mm and 20mm exposure interval. The retardant layer thermal resistance and protection capability were determined. The study was continued to improve the performance of Zinc Borate layer mixed by 10%, 20% and 30% of Antimony Trioxide. To determine the heat transfer of the composite material the opposite surface temperature method was used. Zinc Borate with (30%) Antimony Trioxide gives the optimized result of the experiment.
Sustainable Procedure for Using Waste of Date Seeds as a Reinforcement Material for Polymeric Composites  [PDF]
Ali I. Al-Mosawi, Shaymaa Abbas Abdulsada, Abbass A. Hashim
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1104384
In this article, particles of date seeds as a natural strengthening of the polyester resin and reinforcing percentages (1, 2, 3) wt% were used. For the purpose of comparison with the properties that were obtained in these composite materials reinforced by date seeds, particles have been manufacturing a composite material of the same resin reinforced particles calcium carbonate industrial, the same reinforcing percentages above. Results showed the samples that contain date seeds have a high resistance strain compared to models that contain calcium carbonate and this increase in tensile strength increases with the amount of particles date seeds, plus a big improvement in impact resistance samples have particles date seeds and increases with increasing reinforcement ratio compared with sample have calcium carbonate particles.
Hybrid-Based Compressed Domain Video Fingerprinting Technique
Abbass S. Abbass,Aliaa A. A. Youssif,Atef Z. Ghalwash
Computer and Information Science , 2012, DOI: 10.5539/cis.v5n5p25
Abstract: Video fingerprinting is a newer research area. It is also called “content-based video copy detection” or “content-based video identification” in literature. The goal is to locate videos with segments substantially identical to segments of a query video while tolerating common artifacts in video processing. Its value as a tool to curb piracy and legally monetize contents becomes more and more apparent in recent years with the wide spread of Internet videos through user generated content (UGC) sites like YouTube. Its practical applications to a certain extent overlap with those of digital watermarking, which requires adding artificial information into the contents. Fingerprints are compact content-based signature that summarizes a video signal or another media signal. Several video fingerprinting methods have been proposed for identifying video, in which fingerprints are extracted by analyzing video in both spatial and temporal dimension. However, these conventional methods have one resemblance, in which video decompression is still required for extracting the fingerprint from a compressed video. In practical, faster computational time can be achieved if fingerprint is extracted directly from the compressed domain. So far, too fewer methods are known to propose video fingerprinting in compressed domain. This paper presents a video fingerprinting technique that works directly in the compressed domain. Experimental results show that the proposed fingerprint is highly robust against most signal processing transformations.
Estimating the Thickness of Sedimentation within Lower Benue Basin and Upper Anambra Basin, Nigeria, Using Both Spectral Depth Determination and Source Parameter Imaging
Adetona A. Abbass,Abu Mallam
ISRN Geophysics , 2013, DOI: 10.1155/2013/124706
Abstract: The Total Aeromagnetic Data covering the study area was subjected to First Vertical Derivative, Spectral Depth Analysis, and Source Parameter Imaging (SPI). The result from the First Vertical Derivative shows that the Northern part of the area is covered by the young biotite granite of Precambrian origin, and the western edge is covered by the old granite, gneisses, and migmatite of Western Nigeria, while the remaining area is covered by the cretaceous sedimentary deposits. The entire area was divided into forty-eight sections. Spectral Depth Analysis was run for each of these forty-eight sections; the result shows that a maximum depth above 7?km was obtained within the cretaceous sediments of Idah, Ankpa, and below Udegi at the middle of the study area. Minimum depth estimates between 188.0 and 452 meters were observed around the basement regions. Results from Source Parameter Imaging show a minimum depth of 76.983 meters and a maximum thickness of sedimentation of 9.847?km, which also occur within Idah, Ankpa, and Udegi axis. The disparity observed in depth obtained by each method is discussed based on the merit and demerit of each method, and the depths obtained were compared with results from previous researchers. Geophysical implication of the result to oil and gas exploration in the area is briefly discussed. 1. Introduction Of all the magnetic minerals that occur in nature, magnetite is the most abundant. Aeromagnetic surveys reflect almost exclusively the distribution of magnetite and pyrrhotite in rocks. On a global basis, the others can probably be ignored [1, 2]. Thus aeromagnetic surveys, in particular terms, map the magnetite in the rocks below the aircraft. While aeromagnetic surveys are extensively used as reconnaissance tools, there has been an increasing recognition of their value for evaluating prospective areas by virtue of the unique information they provide. Outline of the roles of aeromagnetic survey is as follows [3].(i)Delineation of volcano-sedimentary belts under sand or other recent cover, or in strongly metamorphosed terrains when recent lithologies are otherwise unrecognizable. (ii)Recognition and interpretation of faulting, shearing, and fracturing not only as potential hosts for a variety of minerals, but also an indirect guide to epigenetic, stress related mineralization in the surrounding rocks. (iii)Identification and delineation of post-tectonic intrusive. Typical of such targets are zoned syenite or carbonatite complexes, kinerlites, tin-bearing granites, and mafic intrusions. (iv)Direct detection of deposits of
Ali I. Al-Mosawi,Haider K. Ammash,Mohammad H.Al-Maamori,Abbass Hashim
Academic Research International , 2012,
Abstract: Aircraft tire must withstand and a wide range of operational conditions .When on the ground, it must support the weight of the aircraft. During taxi, it must provide a stable cushioned ridewhile resisting heat generation, abrasion and wear. When aircraft down ,the tire may be fired because high friction with ground. So to protect aircrafts tires from fires Magnesium hydroxide was used in various quantities (10%,20%,30%) as a flame retardant toenhancement flame retardancy for tires material. Magnesium hydroxide was added with master batch of tire and then exposed the resulting material to a direct flame generated from gas flame (2000oC) with flame exposure distance (10 mm), and study the range of tireresistance to the flame and the range protected of hydroxide addition . Method of measuring the surface temperature opposite to the flame was used to determine the heat transferred through tire material. The results was obtained from thermal erosion test shows improved flammability resistance for tire by added magnesium hydroxide and this resistance increased by increasing hydroxide percentage .
The Relationship between Using of an Intelligent Tutoring System and Class Achievement in a Basic Mathematics Course
Abbass el Sharif,Ramzi A. Haraty
International Journal of Emerging Technologies in Learning (iJET) , 2008,
Abstract: In this paper, we present a case in which weintegrated an intelligent tutoring system- ITS- in a basicmathematics course. The proposed ITS –PrivateTutor- isdynamic, web-based, adaptive, and interactive. It iscomposed of six different modules; each has a distinctfunction: student, domain, question, communication, expert,and controller modules. The purpose of this system is not toeliminate the role of human teachers, but to complementtheir effort in reaching all students and having one-to-onetutoring approach instead one-to-many. An experiment wasconducted in order to study the effectiveness ofPrivateTutor on class achievement. Students who wereenrolled in a “Basic Mathematics” course in the Fall of2005-2006 and Spring of 2006 at the Lebanese AmericanUniversity were randomly assigned to two groups: controland treatment. The experimental results failed to show anysignificant positive effect.
Internal Auditors’ Characteristics and Audit Fees: Evidence from Egyptian Firms
Dalia A. Abbass,Mahmoud M. Aleqab
International Business Research , 2013, DOI: 10.5539/ibr.v6n4p67
Abstract: Reliance of external auditors on the work of internal auditors is very important but yet, complex decision tasks that require professional judgment as it is influenced by a number of factors, characteristics of internal auditors are of the most important factors to be considered. The paper obtains various criteria relating to the evaluation of internal audit organizational status, work performed, competence, and professional due care as stipulated in Professional Auditing Standards including the Egyptian Auditing Standard (EAS)No.610 “Using the work of internal auditors”. This study revealed that internal auditors’ characteristics assist in increasing external auditors’ reliance on their works and so minimize external auditors’ efforts and so fees. Data on internal audit characteristics are obtained from survey respondents of Egyptian companies and audit fee data are obtained from their annual reports. Results indicate that lower external audit fees are associated with top management support for internal auditors, not imposing constraints on internal auditors works, is ready to act upon internal audit staff findings and recommendations, adequacy of education of internal auditors, good practices for hiring and training internal auditors. Also, lower external audit fees are associated with adequacy of working paper documentation supporting internal auditors’ conclusions, sufficiency of internal auditors’ evidences.
Supersymmetry of the Morse oscillator
Hashim A Yamani,Zouhair Mouayn
Physics , 2015,
Abstract: While dealing in [1] with the supersymmetry of a tridiagonal Hamiltonian H, we have proved that its partner Hamiltonian H(+) also have a tridiagonal matrix representation in the same basis and that the polynomials associated with the eigenstates expansion of H(+) are precisely the kernel polynomials of those associated with H. This formalism is here applied to the case of the Morse oscillator which may have a finite discrete energy spectrum in addition to a continuous one. This completes the treatment of tridiagonal Hamiltonians with pure continuous energy spectrum, a pure discrete one, or a spectrum of mixed discrete and continous parts.
Oiling the Wheels of Change: The Role of Adaptive Automatic Problem Decomposition in Non--Stationary Environments
H. A. Abbass,K. Sastry,D. E. Goldberg
Computer Science , 2005,
Abstract: Genetic algorithms (GAs) that solve hard problems quickly, reliably and accurately are called competent GAs. When the fitness landscape of a problem changes overtime, the problem is called non--stationary, dynamic or time--variant problem. This paper investigates the use of competent GAs for optimizing non--stationary optimization problems. More specifically, we use an information theoretic approach based on the minimum description length principle to adaptively identify regularities and substructures that can be exploited to respond quickly to changes in the environment. We also develop a special type of problems with bounded difficulties to test non--stationary optimization problems. The results provide new insights into non-stationary optimization problems and show that a search algorithm which automatically identifies and exploits possible decompositions is more robust and responds quickly to changes than a simple genetic algorithm.
Visualizing Cognitive Moves for Assessing Information Perception Biases in Decision Making
Antony W. Iorio,Hussein A. Abbass,Svetoslav Gaidow,Axel Bender
Computer Science , 2014,
Abstract: In decision making a key source of uncertainty is people's perception of information which is influenced by their attitudes toward risk. Both, perception of information and risk attitude, affect the interpretation of information and hence the choice of suitable courses of action in a variety of contexts ranging from project planning to military operations. Visualization associated with the dynamics of cognitive states of people processing information and making decision is therefore not only important for analysis but has also significant practical applications, in particular in the military command and control domain. In this paper, we focus on a major concept that affect human cognition in this context: reliability of information. We introduce Cognitive Move Diagrams (CMD)---a simple visualization tool---to represent and evaluate the impact of this concept on decision making. We demonstrate through both a hypothetical example and a subject matter expert based experiment that CMD are effective in visualizing, detecting and qualifying human biases.

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