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Improved CBIR through Combined Indexing Techniques
No full textMultimedia databases get larger and larger in our days. There are various aspects that affect the demand for efficient database techniques to manage the flood of
multimedia data, namely the increasing number of objects, the increasing complexity of objects. Whereas traditional indexing structures cope with large numbers of simple objects, complex multimedia objects require more sophisticated indexing
techniques. In this paper we discuss the current state-of-theart of various indexing technique as seen from content-based image retrieval point of view and proposed a novel approach named Hierarchical Hash Grid Indexing structure which has excellent performance and capable of handling huge number of images with less response time
Towards Software Engineering Process for C4I Systems
No full textCommand Control, Communication Computer and Intelligence (C4I) systems enables modern military forces to achieve information superiority in the battlefield. C4I are complex System of systems (SOS) where individual systems interact locally to achieve global SOS behaviors. To build software for C4I systems conventional software engineering SwE process and practices have shortcomings and are not capable to support certain aspect of these systems. If C4I systems fail to operate as required due to the fact that SwE process was unable to fulfill its requirements, the consequences may not be tolerated because of the criticality of the mission of these systems in information warfare (IW). This paper highlights the distinguished characteristics and operational requirements of C4I systems which poses challenges to SwE process and practices. This paper also discuss the possible future research areas in order to enhance SwE process so that better software could drive these complex systems as required
Tackling the Problem of Invariant Image Retrieval Using Multiple Representations and Multiple Queries - Application to Textures
No full textWe present in this paper an approach based on multiple strategies to tackle the problem of invariance in the framework of texture-based image retrieval. This approach, rather than to consider invariance at the representation level, considers it at the query level. We use two models to represent the visual content of textures, namely, the autoregressive model and a perceptual model based on a set of perceptual features. The perceptual model is used with two viewpoints: the original image's viewpoint and the autocovariance function viewpoint. After a brief presentation and discussion of these multiple representation models/viewpoints, we present the invariant texture retrieval algorithm. This algorithm considers results fusion (merging) at two different levels: (1) the first level consists in merging results returned by different models/viewpoints (representations) for the same query in one results list using a linear results fusion model; (2) the second level consists in merging each fused list of different queries into a unique fused list using a round robin fusion scheme. Experimental retrieval results and benchmarking based on the precision/recall measures applied on a large image database show interesting results
Computational Perceptual Features for Texture Representation and Retrieval
No full textA perception-based approach to content-based image representation and retrieval is proposed in this paper. We consider textured images and propose to model their textural content by a set of features having a perceptual meaning and their application to content-based image retrieval. We present a new method to estimate a set of perceptual textural features, namely coarseness, directionality, contrast, and busyness. The proposed computational measures can be based upon two representations: the original images representation and the autocorrelation function (associated with original images) representation. The set of computational measures proposed is applied to content-based image retrieval on a large image data set, the well-known Brodatz database. Experimental results and benchmarking show interesting performance of our approach. First, the correspondence of the proposed computational measures to human judgments is shown using a psychometric method based upon the Spearman rank-correlation coefficient. Second, the application of the proposed computational measures in texture retrieval shows interesting results, especially when using results fusion returned by each of the two representations. Comparison is also given with related works and show excellent performance of our approach compared to related approaches on both sides: correspondence of the proposed computational measures with human judgments as well as the retrieval effectiveness
Forced convection heat transfer over horizontal triangular cylinder in cross flow
No full textExperimental investigations have been reported on steady state forced convection heat transfer from the outer surface of horizontal triangular surface cylinders in cross flow of air. Two different horizontal positions are considered; one when the vertex of the triangle faces the flow and the other when the flat surface faces the flow. Four equilateral triangular cylinders have been used with cross section side length of 0.03, 0.05, 0.08 and 0.12 m, corresponding to blockage ratios 0.066, 0.110, 0.175 and 0.263 respectively. The cylinders are heated using internal constant heat flux heating elements. The temperatures along the surface and peripheral directions of the cylinder wall are measured. Local Nusselt numbers at the middle of the cylinder are obtained around the perimeter for the larger cylinders 0.12 and 0.08 m for various Reynolds numbers. Total overall averaged Nusselt numbers are obtained for transition to turbulent regime and these critical points are tabulated. Empirical correlations are obtained for the overall averaged Nusselt numbers and Reynolds number using the equilateral side length as a characteristic length for the two positions of the cylinders. Furthermore, other general correlations are obtained for the overall averaged Nusselt number using the cylinder length as a characteristic length and the blockage ratio as a parameter.King Saud Universit
The effect of topically applied 1.23% acidulated phosphate fluoride on zinc phosphate cement
No full textTopically applied fluoride preparations play an important role in reduction of caries incidence. It was found that the commonly used 1.23% acidulated phosphate fluoride (APF) gel has a deleterious effect on different dental materials. The effect of the gel on zinc phosphate cement is still not known. It is expected that 1.23% APF gel may affect the microstructure of the zinc phosphate cement. Thirty Teflon rings were prepared. Zinc phosphate cement was mixed and loaded into the rings. Excess cement material was removed and samples were stored in 20 ml of distilled water at 37°C for 24 hours. They were then equally divided into five groups. Samples of the control group were stored in 20 ml of distilled water at 37°C for 24 hours. The other four groups received four times application of 1.23% APF gel for 1, 4, 6 and 10 minutes at each application with an intermediate washing and immersion in 20 ml of distilled water at 37°C for one hour between applications. Samples were prepared for examination under the scanning electron microscope. Results showed that as the application time of the gel is increased, more reaction products are formed on the surface of the set zinc phosphate cement. These products mask and may protect the surface from erosion by the acidic APF gel. However, more surface roughness is produced that may accumulate bacteria and affect the gingival health.King Saud Universit
Space Maintainers Utilization by 6-7 Years Old Girls in Riyadh – Saudi Arabia
No full textThis cross-sectional study aimed to report utilization of space maintainers by first and second grade female (6 & 7 year old) students in Riyadh Saudi Arabia.
Materials & Methods: A total of 609 school girls were included in the study. The schools were randomly selected from a list of all public elementary girls' schools to represent the five different educational zones of Riyadh city. Dental examination was conducted in schools by one examiner visually using penlight, individually wrapped and sterilized mouth mirrors and gloves.
Results: Out of the 609 children examined, {337 (55.3%) were 6 year old and 272 (44.7%) were 7 year old}, 156 (25.6%) had premature loss of teeth. All the prematurely missing teeth were primary molars and or canines except for two children where each of them had one of the permanent incisors prematurely missing. Only 6 children (1.3%) utilized space maintainers in the place of tooth loss. A total of 8 space maintainers were utilized by the 6 children replacing missing primary molars. No space maintainer was utilized in place of missing primary canines or permanent incisors. Fifty percent of the children (24) having primary canines prematurely missing had their midline shifted to the affected side.
Conclusions: From the present study we can conclude that only very few (1.3%) of the examined children utilized space maintainers after premature tooth loss. Increasing the parent's knowledge about the consequences of premature loss of primary teeth, the importance of maintaining the space of a lost tooth, and encouraging dental practitioners to use the space maintainers whenever indicated are all needed to reduce the expected malocclusion.King Saud Universit
Consensus building and recommendations based on the available epidemiology of meningococcal disease in Gulf Cooperation Council States.
No full textThe Gulf Cooperation Council (GCC) States share concerns about meningococcal disease, particularly in association with the Hajj and Umrah pilgrimages, which have been connected with outbreaks within the Kingdom of Saudi Arabia and among contacts of the pilgrims in their countries of origin. Currently, the most prevalent meningococcal serogroup in the GCC States is W-135. Although vaccination with polysaccharide vaccines has protected pilgrims and their close contacts from invasive disease, the potential availability of novel conjugate vaccines, such as the one currently used for vaccination of military personnel in the Kingdom of Saudi Arabia, prompted an evaluation of disease epidemiology in the region. For several countries, published data on recent epidemiology are not available. We report findings from a meeting of the GCC States Meningitis Study Group, which comprised experts from the Kingdom of Saudi Arabia, the Kingdom of Bahrain, Kuwait, Qatar, the Sultanate of Oman, and the United Arab Emirates. These experts provided an update on epidemiology and current vaccination practices in the GCC States, and discussed new approaches to more effective disease prevention. Copyright © 2011 Elsevier Ltd. All rights reserved
Oil components modulate the skin delivery of 5-aminolevulinic acid and its ester prodrug from oil-in-water and water-in-oil nanoemulsions
No full textThe study evaluated the potential of nanoemulsions for the topical delivery of 5-aminolevulinic acid (ALA) and methyl ALA (mALA). The drugs were incorporated in oil-in-water (O/W) and water-in-oil (W/O) formulations obtained by using soybean oil or squalene as the oil phase. The droplet size, zeta potential, and environmental polarity of the nanocarriers were assessed as physicochemical properties. The O/W and W/O emulsions showed diameters of 216-256 and 18-125 nm, which, respectively, were within the range of submicron- and nano-sized dispersions. In vitro diffusion experiments using Franz-type cells and porcine skin were performed. Nude mice were used, and skin fluorescence derived from protoporphyrin IX was documented by confocal laser scanning microscopy (CLSM). The loading of ALA or mALA into the emulsions resulted in slower release across cellulose membranes. The release rate and skin flux of topical drug application were adjusted by changing the type of nanocarrier, the soybean oil O/W systems showing the highest skin permeation. This formulation increased ALA flux via porcine skin to 180 nmol/cm(2)/h, which was 2.6-fold that of the aqueous control. The CLSM results showed that soybean oil systems promoted mALA permeation to deeper layers of the skin from ∼100 μm to ∼140 μm, which would be beneficial for treating subepidermal and subcutaneous lesions. Drug permeation from W/O systems did not surpass that from the aqueous solution. An in vivo dermal irritation test indicated that the emulsions were safe for topical administration of ALA and mALA.
DOI: 10.2147/IJN.S1752
Anti-breast cancer activity of some novel 1,2-dihydropyridine, thiophene and thiazole derivatives.
No full textA variety of novel 1,2-dihydropyridines 10-17, thiophenes 18-21 and thiazole 22 having a biologically active sulfone moiety were obtained via the reaction of 2-cyano-N'-[1-(4-(piperidin-1-ylsulfonyl) phenyl) ethylidene] acetohydrazide 3 with a variety of reagents. The structures of the newly synthesized compounds were confirmed by elemental analysis, IR, (1)H NMR, (13)C NMR and mass spectral data. All the newly synthesized compounds were evaluated for their in-vitro anticancer activity against human breast cancer cell line (MCF7). Compounds 15 and 11 with IC(50) values (20.6, 25.5 μM) exhibited better activity than Doxorubicin as a reference drug with IC(50) value (32.02 μM), while compound 14 is nearly as active as Doxorubicin as positive control. Copyright © 2010 Elsevier Masson SAS. All rights reserved.
DOI: 10.1016/j.ejmech.2010.10.02