Background:In this study,TiO2 layer was thermally grown as a diffusion barrier on CP Ti substrate prior to electrophoretic deposition of HA coatings, to improve the coating’s compatibility also macro and micro pores in nano Hydroxyapatite dual coatings were created and their effect on the bond strength between the bone and implant was evaluated. Materials and methods: Electrophoretic Deposition technique (EPD) was used to obtain coatings for each one of four types of Hydroxyapatite(HA)on CP Ti screws (micro HA, nano HA, dual nano HA with micro pores, dual nano HA with macro pores) where carbon particles used as fugitive material to be removed by thermal treatment to create porosity.For examination of the changes occurred on the substrate, SEM, SPM and XRD used, coatings characterized by XRD, SEM and interfacial shear strength measurements. Results:The results mentioned the formation of rutilenano TiO2 with, SEM showed that the size of pores in HA coatings corresponded to the size of carbon particles. Statistical analysis of the removal torque tests showed highest means of the single nano HA coating at 2 and 4 weeks implantation intervals. Histological analysisrevealed a faster reaction of bone and higher osteoblasts activity towards thermally oxidized CP Ti implants coated with single nano HA coating. Conclusion:Carbon particles as a fugitive material within nano HA coat produced porosity.Presence of pores ˃ 1µ in nano HA coats did not achieve highest removal torque values nor highest osteoblasts activity in 2 and 4 weeks implantation intervals. Keywords:Titanium, Thermal oxidization, Nano Hydroxyapatite, Coatings, porosity.
This paper proposed to build an authentication system between business partners on e-commerce application to prevent the frauds operations based on visual cryptography shares encapsulated by chen’s hyperchaotic key sequence. The proposed system consist of three phases, the first phase based on the color visual cryptography without complex computations, the second phase included generate sequence of DNA rules numbers and finally encapsulation phase is implemented based on use the unique initial value that generate in second phase as initial condition with Piecewise Linear Chaotic Maps to generate sequences of DNA rules numbers. The experimental results demonstrate the proposed able to overcome on cheating a
... Show MoreThis work is concerned with the design and performance evaluation of a shell and double concentric tubes heat exchanger using Solid Works and ANSY (Computational Fluid Dynamics).
Computational fluid dynamics technique which is a computer-based analysis is used to simulate the heat exchanger involving fluid flow, heat transfer. CFD resolve the entire heat exchanger in discrete elements to find: (1) the temperature gradients, (2) pressure distribution, and (3) velocity vectors. The RNG k-ε model of turbulence is used to determining the accurate results from CFD.
The heat exchanger design for this work consisted of a shell and eight double concentric tubes. The number of inlets are three and that of o
... Show MoreThe Non-Photorealistic Rendering (NPR) demands are increased with the development of electronic devices. This paper presents a new model for a cartooning system, as an essential category of the NPR. It is used the concept of vector quantization and Logarithmic Image Processing (LIP). An enhancement of Kekre Median Codebook Generation (KMCG) algorithm has been proposed and used by the system. Several metrics utilized to evaluate the time and quality of the system. The results showed that the proposed system reduced the time of cartoon production. Additionally, it enhanced the quality of several aspects like smoothing, color reduction, and brightness.
Hiding secret information in the image is a challenging and painstaking task in computer security and steganography system. Certainly, the absolute intricacy of attacks to security system makes it more attractive.in this research on steganography system involving information hiding,Huffman codding used to compress the secret code before embedding which provide high capacity and some security. Fibonacci decomposition used to represent the pixels in the cover image, which increase the robustness of the system. One byte used for mapping all the pixels properties. This makes the PSNR of the system higher due to random distribution of embedded bits. Finally, three kinds of evaluation are applied such as PSNR, chi-square attack, a
... Show MoreNew data on jumping spiders (Salticidae) and tangle-web spiders (Theridiidae) of Armenia are provided on the basis of recently collected specimens in various regions of Armenia. One species, Ballus rufipes (Simon, 1868) is recorded as new to the Caucasus Region, in addition to the following species: Neon reticulatus (Blackwall, 1853), Pellenes brevis (Simon, 1868), Salticus scenicus (Clerck, 1757) and Synageles dalmaticus (Keyserling, 1863) that belong to a family Salticidae, are recorded in Armenia for the first time.
A further 7 species of Theridiidae are recorded in Armenia for the first time Kochiura aulica (C. L. Koch, 1838), Steatoda albomaculata (De Geer, 1778), Steatoda bipunctata (Linnaeus, 1758), Steatoda castanea Clerk, 175
The fact that the signature is widely used as a means of personal verification
emphasizes the need for an automatic verification system. Verification can be
performed either Offline or Online based on the application. Offline systems work on
the scanned image of a signature. In this paper an Offline Verification of handwritten
signatures which use set of simple shape based geometric features. The features used
are Mean, Occupancy Ratio, Normalized Area, Center of Gravity, Pixel density,
Standard Deviation and the Density Ratio. Before extracting the features,
preprocessing of a scanned image is necessary to isolate the signature part and to
remove any spurious noise present. Features Extracted for whole signature
The research aims to determine the role of functional alienation and its impact on Job Satisfaction in General Motors Company, that were selected to apply the field side being an important company in Iraq, the problem was research with difficulty in employees adapt and their sense of alienation in their work which is reflected negatively on the level of satisfaction with work in company searched. A questionnaire was adopted as the main tool for data collection research which included (31) items distributed on (50) employees in the company selected, on a randomly chosen and based on the statistical program ready by (SPSS). Sample of this study was the most important findings of the research are the weak management of the company i
... Show MoreIn this paper we define and study new concepts of fibrewise topological spaces over B namely, fibrewise Lindelöf and locally Lindelöf topological spaces, which are generalizations of will-known concepts: Lindelöf topological space (1) "A topological space X is called a Lindelöf space if for every open cover of X has a countable subcover" and locally Lindelöf topological space (1) "A topological space X is called a locally Lindelöf space if for every point x in X, there exist a nbd U of x such that the closure of U in X is Lindelöf space". Either the new concepts are: "A fibrewise topological space X over B is called a fibrewise Lindelöf if the projection function p : X→B is Lindelöf" and "The fibrewise topological space X over B
... Show MoreAutomatic recognition of individuals is very important in modern eras. Biometric techniques have emerged as an answer to the matter of automatic individual recognition. This paper tends to give a technique to detect pupil which is a mixture of easy morphological operations and Hough Transform (HT) is presented in this paper. The circular area of the eye and pupil is divided by the morphological filter as well as the Hough Transform (HT) where the local Iris area has been converted into a rectangular block for the purpose of calculating inconsistencies in the image. This method is implemented and tested on the Chinese Academy of Sciences (CASIA V4) iris image database 249 person and the IIT Delhi (IITD) iris
... Show MoreImage content verification is to confirm the validity of the images, i.e. . To test if the image has experienced any alteration since it was made. Computerized watermarking has turned into a promising procedure for image content verification in light of its exceptional execution and capacity of altering identification.
In this study, a new scheme for image verification reliant on two dimensional chaotic maps and Discrete Wavelet Transform (DWT) is introduced. Arnold transforms is first applied to Host image (H) for scrambling as a pretreatment stage, then the scrambled host image is partitioned into sub-blocks of size 2×2 in which a 2D DWT is utilized on ea
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