Search results for: vortex formation length

Authors: Qasem M. Al-Mdallal

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This paper presents results obtained from the numerical solution for the flow past an oscillating circular cylinder at Reynolds number of 200. The frequency of oscillation was fixed to the vortex shedding frequency from a fixed cylinder, f0, while the amplitudes of oscillations were varied from to 1.1a, where a represents the radius of the cylinder. The response of the flow through the fluid forces acting on the surface of the cylinder are investigated. The lock-on phenomenon is captured at low oscillation amplitudes.

Keywords: Lock-on; streamwise oscillation; transverse oscillation; fluid forces, combined motion

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Authors: Kollarama Subramanyam, Nisha Kuruvilla, J. P. Raina

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Novel compact expressions for propagation constant (γ) of SWCNT and bundled SWCNTs interconnect, in terms of physical parameters such as length, operating frequency and diameter of CNTs is proposed in this work. These simplified expressions enable physical insight and accurate estimation of signal attenuation level and its phase change at any length for a particular frequency. The proposed expressions are validated against SPICE simulated results of lumped as well as distributed equivalent electrical RLC nets of CNT interconnect. These expressions also help us to evaluate the cut off frequencies of SWCNTs for different interconnect lengths.

Keywords: Attenuation constant, Bundled SWCNT, CNT interconnects, Propagation Constant.

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Authors: Levan Nadareishvili, Roland Bakuradze, Barbara Kilosanidze, Nona Topuridze, Liana Sharashidze, Ineza Pavlenishvili

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Some regularities of formation of a new structural state of the thermoplastic polymers - gradually oriented (stretched) state (GOS) are discussed. Transition into GOS is realized by the graded oriented stretching - by action of inhomogeneous mechanical field on the isotropic linear polymers or by zone stretching that is implemented on a standard tensile-testing machine with using a specially designed zone stretching device (ZSD). Both technical approaches (especially zone stretching method) allows to manage the such quantitative parameters of gradually oriented polymers as a range of change in relative elongation/orientation degree, length of this change and profile (linear, hyperbolic, parabolic, logarithmic, etc.). The possibility of obtaining functionally graded materials (FGMs) by graded orientation method is briefly discussed. Uniaxial graded stretching method should be considered as an effective technological solution to create polymer materials with a predetermined gradient of physical properties.

Keywords: Controlled graded stretching, gradually oriented state, linear polymers, zone stretching device.

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Authors: Surinder Singh, Adish Bindal

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The effects of the pumping wavelength and their power on the gain flattening of a fiber Raman amplifier (FRA) are investigated. The multi-wavelength pumping scheme is utilized to achieve gain flatness in FRA. It is proposed that gain flatness becomes better with increase in number of pumping wavelengths applied. We have achieved flat gain with 0.27 dB fluctuation in a spectral range of 1475-1600 nm for a Raman fiber length of 10 km by using six pumps with wavelengths with in the 1385-1495 nm interval. The effect of multi-wavelength pumping scheme on gain saturation in FRA is also studied. It is proposed that gain saturation condition gets improved by using this scheme and this scheme is more useful for higher spans of Raman fiber length.

Keywords: FRA, gain, pumping, WDM.

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Authors: A. A. Amer, H. M. Gad, I. A. Ibrahim, S. I. Abdel-Mageed, T. M. Farag

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This paper represents an experimental study of LPG diffusion flame at elevated preheated air temperatures. The flame is stabilized in a vertical water-cooled combustor by using air swirler. An experimental test rig was designed to investigate the different operating conditions. The burner head is designed so that the LPG fuel issued centrally and surrounded by the swirling air issues from an air swirler. There are three air swirlers having the same dimensions but having different blade angles to give different swirl numbers of 0.5, 0.87 and 1.5. The combustion air was heated electrically before entering the combustor up to a temperature about 500 K. Five air to fuel mass ratios of 15, 20, 30, 40 and 50 were also studied. The effect of preheated air temperature, swirl number and air to fuel mass ratios on the temperature maps, visible flame length, high temperature region (size) and exhaust species concentrations are studied. Some results show that as the preheated air temperature increases, the volume of high temperature region also increased but the flame length decreased. Increasing the preheated air temperature, EINOx, EICO2 and EIO2 increased, while EICO decreased. Increasing the preheated air temperature from 300 to 500 K, for all air swirl numbers used, the highest increase in EINOx, EICO2 and EIO2 are 141, 4 and 65%, respectively.

Keywords: Preheated air temperature, air swirler, flame length, emission index.

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Authors: N. G. Margiani, I. G. Kvartskhava, G. A. Mumladze, Z. A. Adamia

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Chemical doping with different elements and compounds at various amounts represents the most suitable approach to improve the superconducting properties of bismuth-based superconductors for technological applications. In this paper, the influence of partial substitution of Sr(BO₂)₂ for SrO on the phase formation kinetics and transport properties of (Bi,Pb)-2223 HTS has been studied for the first time. Samples with nominal composition Bi_1.7Pb_0.3Sr_2-xCa₂Cu₃O_y[Sr(BO₂)₂]_x, x=0, 0.0375, 0.075, 0.15, 0.25, were prepared by the standard solid state processing. The appropriate mixtures were calcined at 845 ^oC for 40 h. The resulting materials were pressed into pellets and annealed at 837 ^oC for 30 h in air. Superconducting properties of undoped (reference) and Sr(BO₂)₂-doped (Bi,Pb)-2223 compounds were investigated through X-ray diffraction (XRD), resistivity (ρ) and transport critical current density (J_c) measurements. The surface morphology changes in the prepared samples were examined by scanning electron microscope (SEM). XRD and J_c studies have shown that the low level Sr(BO₂)₂ doping (x=0.0375-0.075) to the Sr-site promotes the formation of high-T_c phase and leads to the enhancement of current carrying capacity in (Bi,Pb)-2223 HTS. The doped sample with x=0.0375 has the best performance compared to other prepared samples. The estimated volume fraction of (Bi,Pb)-2223 phase increases from ~25 % for reference specimen to ~70 % for x=0.0375. Moreover, strong increase in the self-field J_c value was observed for this dopant amount (J_c=340 A/cm²), compared to an undoped sample (J_c=110 A/cm²). Pronounced enhancement of superconducting properties of (Bi,Pb)-2223 superconductor can be attributed to the acceleration of high-T_c phase formation as well as the improvement of inter-grain connectivity by small amounts of Sr(BO₂)₂ dopant.

Keywords: Bismuth-based superconductor, critical current density, phase formation, Sr(BO2)2 doping.

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Authors: E. Kaygan, A. Gatto

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An investigation of adaptable winglets for morphing aircraft control and performance is described in this paper. The concepts investigated consist of various winglet configurations fundamentally centred on a baseline swept wing. The impetus for the work was to identify and optimize winglets to enhance controllability and the aerodynamic efficiency of a small unmanned aerial vehicle. All computations were performed with Athena Vortex Lattice modelling with varying degrees of twist, swept, and dihedral angle considered. The results from this work indicate that if adaptable winglets were employed on small scale UAV’s improvements in both aircraft control and performance could be achieved.

Keywords: Aircraft, rolling, wing, winglet.

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Authors: Václav Dvořák

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The article deals with numerical investigation of axisymmetric subsonic air to air ejector. An analysis of flow and mixing processes in cylindrical mixing chamber are made. Several modes with different velocity and ejection ratio are presented. The mixing processes are described and differences between flow in the initial region of mixing and the main region of mixing are described. The lengths of both regions are evaluated. Transition point and point where the mixing processes are finished are identified. It was found that the length of the initial region of mixing is strongly dependent on the velocity ratio, while the length of the main region of mixing is dependent on velocity ratio only slightly.

Keywords: Air ejector, mixing chamber, CFD.

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Authors: Е. V. Kutsina, S. A. Tarasova

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In this article we present a methodology which enables preschool and primary school unlanguaged children to remember words, phrases and texts with the help of graphic signs - letters, syllables and words. Reading for a child becomes a support for speech development. Teaching is based on the principle "from simple to complex", "a letter - a syllable - a word - a proposal - a text." Availability of multi-level texts allows using this methodology for working with children who have different levels of speech development.

Keywords: Alalia, analytic-synthetic method, development of coherent speech, formation of vocabulary, learning to read, , sentence formation, three-level stories, unlanguaged children.

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Authors: Hakim Akeb, Mhand Hifi

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In this paper, the use of beam search and look-ahead strategies for solving the strip packing problem (SPP) is investigated. Given a strip of fixed width W, unlimited length L, and a set of n circular pieces of known radii, the objective is to determine the minimum length of the initial strip that packs all the pieces. An augmented algorithm which combines beam search and a look-ahead strategies is proposed. The look-ahead is used in order to evaluate the nodes at each level of the tree search. The best nodes are then retained for branching. The computational investigation showed that the proposed augmented algorithm is able to improve the best known solutions of the literature on most instances used.

Keywords: Combinatorial optimization, cutting and packing, beam search, heuristic, look-ahead strategy.

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Authors: T. N. Janakiraman, J. Janet Lourds Rani

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In practice, wireless networks has the property that the signal strength attenuates with respect to the distance from the base station, it could be better if the nodes at two hop away are considered for better quality of service. In this paper, we propose a procedure to identify delay preserving substructures for a given wireless ad-hoc network using a new graph operation G 2 – E (G) = G* (Edge difference of square graph of a given graph and the original graph). This operation helps to analyze some induced substructures, which preserve delay in communication among them. This operation G* on a given graph will induce a graph, in which 1- hop neighbors of any node are at 2-hop distance in the original network. In this paper, we also identify some delay preserving substructures in G*, which are (i) set of all nodes, which are mutually at 2-hop distance in G that will form a clique in G*, (ii) set of nodes which forms an odd cycle C2k+1 in G, will form an odd cycle in G* and the set of nodes which form a even cycle C2k in G that will form two disjoint companion cycles ( of same parity odd/even) of length k in G*, (iii) every path of length 2k+1 or 2k in G will induce two disjoint paths of length k in G*, and (iv) set of nodes in G*, which induces a maximal connected sub graph with radius 1 (which identifies a substructure with radius equal 2 and diameter at most 4 in G). The above delay preserving sub structures will behave as good clusters in the original network.

Keywords: Clique, cycles, delay preserving substructures, maximal connected sub graph.

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Authors: Jing S. Bai, Li Y. Zou, Tao Wang, Kun Liu, Wen B. Huang, Jin H. Liu, Ping Li, Duo W. Tan, CangL. Liu

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We studied the evolution of elliptic heavy SF6 gas cylinder surrounded by air when accelerated by a planar Mach 1.25 shock. A multiple dynamics imaging technology has been used to obtain one image of the experimental initial conditions and five images of the time evolution of elliptic cylinder. We compared the width and height of the circular and two kinds of elliptic gas cylinders, and analyzed the vortex strength of the elliptic ones. Simulations are in very good agreement with the experiments, but due to the different initial gas cylinder shapes, a certain difference of the initial density peak and distribution exists between the circular and elliptic gas cylinders, and the latter initial state is more sensitive and more inenarrable.

Keywords: About four key words or phrases in alphabeticalorder, separated by commas.

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Authors: M. M. Rashid

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Allah (SWT) bestowed us with the Divine blessing, providing the wonderful source of water as stated in verse 15:22 of Al-Quran. Arabic “Ar-Riaaha Lawaaqiha (ٱلرِّيَـٰحَ لَوَٰقِحَ)” of this verse is translated as “fertilizing winds.” The “fertilizing winds” literally, refer to the winds having the roles: to fertilize something similar to the “zygotes” in humans and animals (formation of clouds in the sky in this case); to produce fertilizers for the plants, crops, etc.; and to pollinate the plants. In this paper, these roles of “fertilizing winds” have been validated by presenting the modern knowledge of science in this regard. Existing interpretations are mostly focused on the “formation of clouds in the sky” while few of them mention about the pollination of trees. The production of fertilizers, in this regard, may also be considered for the interpteration of this verse. It has been observed that the winds contain the necessary components of forming the clouds; the necessary components of producing the fertilizers; and the necessary components to pollinate the plants. The science of meteorology gives us a clear understanding of the formation of clouds. Moreover, we know that the lightning bolts break the nitrogen molecules of winds and the water molecules of vapor to form fertilizers. Pollination is a common role of winds in plant fertilization. All the scientific phenomena presented here give us better interpretations of “fertilizing winds.”

Keywords: Al-Quran, fertilizing winds, meteorology, cloud droplets.

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Authors: Gopalu Karunakaran, Matheswaran Jagathambal, Nguyen Van Minh, Evgeny Kolesnikov, Denis Kuznetsov

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This work investigated the use of Beijerinckia indica extracellular extract for the synthesis of silver nanoparticles using AgNO₃. The formation of nanoparticles was confirmed by different methods, such as UV-Vis absorption spectroscopy, XRD, FTIR, EDX, and TEM analysis. The formation of silver nanoparticles (AgNPs) was confirmed by the change in color from light yellow to dark brown. The absorbance peak obtained at 430 nm confirmed the presence of silver nanoparticles. The XRD analysis showed the cubic crystalline phase of the synthesized nanoparticles. FTIR revealed the presence of groups that acts as stabilizing and reducing agents for silver nanoparticles formation. The synthesized silver nanoparticles were generally found to be spherical in shape with size ranging from 5 to 20 nm, as evident by TEM analysis. These nanoparticles were found to inhibit pathogenic bacterial strains. This work proved that the bacterial extract is a potential eco-friendly candidate for the synthesis of silver nanoparticles with promising antibacterial and antioxidant properties. 

Keywords: Antioxidant activity, antimicrobial activity, Beijerinckia indica, characterisation, extracellular extracts, silver nanoparticles.

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Authors: Togzhan D. Mukasheva, Anel A. Omirbekova, Raikhan S. Sydykbekova, Ramza Zh. Berzhanova, Lyudmila V. Ignatova

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In studying the possibility of using plants as rhizoremediators, barley and grass mixture which showed resistance to various concentrations of oil were selected. The minimum inhibitory effect of oil on these plants by morphological parameters such as survival of plants, length and biomass of shoot and root compared with the control was showed. In determining physiological parameters, a slight decrease in the number of chlorophyll a and b in the leaves of plants was noted. The differences in the ratio of the total surface of the roots to the work surface with the growth of plants in soil with oil in the study of adsorption of the root surface were showed.

Keywords: Length of shoot and root, biomass, chlorophyll a and b, adsorption surface, barley, grass mixture.

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Authors: Patcharin Saechan, Isares Dhuchakallaya

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Thermoacoustic refrigerator is a cooling device which uses the acoustic waves to produce the cooling effect. The aim of this paper is to explore the experimental and numerical feasibility of a standing-wave thermoacoustic refrigerator. The effects of the stack length, position of stack and operating frequency on the cooling performance are carried out. The circular pore stacks are tested under the atmospheric pressure. A low-cost loudspeaker is used as an acoustic driver. The results show that the location of stack installed in resonator tube has a greater effect on the cooling performance, than the stack length and operating frequency, respectively. The temperature difference across the ends of stack can be generated up to 13.7°C, and the temperature of cold-end is dropped down by 5.3°C from the ambient temperature.

Keywords: Cooling performance, Refrigerator, Standing-wave, Thermoacoustics.

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Authors: Aws Al-azawi, John Soraghan

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There is a growing interest in the use of ultrasonic speckle tracking for biomedical image formation of tissue deformation. Speckle tracking is angle independent and has an ability to differentiate soft tissue into benign and malignant regions. In this paper a simulation model for dynamic ultrasound scatterer is presented. The model composes Field-II ultrasonic scatterers and FEM (ANSYS-11) nodes as a regional tissue deformation. A performance evaluation is presented on axial displacement and strain fields estimation of a uniformly elastic model, using speckle tracking based 1D cross-correlation of optimally segmented pre and post-deformation frames. Optimum correlation window length is investigated in terms of highest signal-to-noise ratio (SNR) for a selected region of interest of a smoothed displacement field. Finally, gradient based strain field of both smoothed and non-smoothed displacement fields are compared. Simulation results from the model are shown to compare favorably with FEM results.

Keywords: Speckle tracking, tissue deformation, ultrasonic simulation.

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Authors: Ahmed Amin Mousa, Huda Mazeed, Eman Saad

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The study aims to identify the extent of effectiveness of the artistic formation program using some types of pastes to reduce the hyperactivity of the kindergarten children with learning difficulties. The researchers have discussed the aforesaid topic, where the research sample included 120 children of ages between 5 to 6 years, from five schools for special needs, learning disability section, Cairo Governorate. The study used the quasi-empirical method, which depends on designing one group using the pre& post application measurements for the group to validate both, hypothesis and effectiveness of the program. The variables of the study were specified as follows; artistic formation program using Paper Mache as an independent variable, and its effect on the skills of kindergarten child with learning disabilities, as a dependent variable. The researchers utilized the application of an artistic formation program consisting of artistic and musical skills for kindergarten children with learning disabilities. The tools of the study, designed by the researchers, included: observation card used for recording the culling paper using pulp molding skills for kindergarten children with learning difficulties during practicing the artistic formation activity. Additionally, there was a program utilizing Artistic and Musical Activities for kindergarten children with learning disabilities to acquire educational concepts. The study was composed of 20 lessons for fine art activities and 20 lessons for musical activities, with obligation of giving the musical lesson with art lesson in one session to cast on the kindergarten child some educational concepts.

Keywords: musical activities, developing skills, early childhood, educational concepts, learning difficulties

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Authors: M. Benachour, N. Benachour, M. Benguediab

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In this investigation variation of cyclic loading effect on fatigue crack growth is the studied. This study is performed on 2024 T351 and 7050-T74 aluminum alloys, used in aeronautical structures. The propagation model used in this study is NASGRO model. In constant amplitude loading (CA), effect of stress ratio has been investigated. Fatigue life and fatigue crack growth rate were affected by this factor. Results showed an increasing in fatigue crack growth rates (FCGRs) with increasing stress ratio. Variable amplitude loading (VAL) can take many forms i.e. with a single overload, overload band… etc. The shape of these loads affects strongly the fracture life and FCGRs. The application of a single overload (ORL) decrease the FCGR and increase the delay crack length caused by the formation of a larger plastic zone compared to the plastic zone due without VAL. The fatigue behavior of the both material under single overload has been compared.

Keywords: Fatigue crack growth, overload ratio, stress ratio, generalized willenborg model, retardation, Al-alloys.

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Authors: Wen-Yin Huang, Jia-Jie Liu, Jou-Ming Chang

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Faults in a network may take various forms such as hardware/software errors, vertex/edge faults, etc. Folded hypercube is a well-known variation of the hypercube structure and can be constructed from a hypercube by adding a link to every pair of nodes with complementary addresses. Let FFv (respectively, FFe) be the set of faulty nodes (respectively, faulty links) in an n-dimensional folded hypercube FQn. Hsieh et al. have shown that FQn - FFv - FFe for n ≥ 3 contains a fault-free cycle of length at least 2n -2|FFv|, under the constraints that (1) |FFv| + |FFe| ≤ 2n - 4 and (2) every node in FQn is incident to at least two fault-free links. In this paper, we further consider the constraints |FFv| + |FFe| ≤ 2n - 3. We prove that FQn - FFv - FFe for n ≥ 5 still has a fault-free cycle of length at least 2n - 2|FFv|, under the constraints : (1) |FFv| + |FFe| ≤ 2n - 3, (2) |FFe| ≥ n + 2, and (3) every vertex is still incident with at least two links.

Keywords: Folded hypercubes, interconnection networks, cycle embedding, faulty elements.

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Authors: Saeed Mohammed Baneamoon, Rosalina Abdul Salam

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Robotic system is an important area in artificial intelligence that aims at developing the performance techniques of the robot and making it more efficient and more effective in choosing its correct behavior. In this paper the distributed learning classifier system is used for designing a simulated control system for robot to perform complex behaviors. A set of enhanced approaches that support default hierarchies formation is suggested and compared with each other in order to make the simulated robot more effective in mapping the input to the correct output behavior.

Keywords: Learning Classifier System, Default Hierarchies, Robot Behaviors.

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Authors: R. Pesce Delfino, M. Selvaggi, G. V. Celano, C. Dario

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Data on 657 lactation from 163 Maltese goat, collected over a 5-year period were analyzed by a mixed model to estimate the variance components for heritability. The considered lactation traits were: milk yield (MY) and lactation length (LL). Year, parity and type of birth (single or twin) were significant sources of variation for lactation length; on the other hand milk yield was significantly influenced only by the year. The average MY was 352.34 kg and the average LL was 230 days. Estimates of heritability were 0.21 and 0.15 for MY and LL respectively. These values suggest there is low correlation between genotype and phenotype so it may be difficult to evaluate animals directly on phenotype. So, the genetic improvement of this breed may be quite slow without the support of progeny test aimed to select Maltese breeders.

Keywords: Heritability estimate, lactation traits, Maltese goat

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Authors: Chouvalit Khancome, Veera Boonjing

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This paper proposes a new solution to string matching problem. This solution constructs an inverted list representing a  string pattern to be searched for. It then uses a new algorithm to process an input string in a single pass. The preprocessing phase  takes 1) time complexity O(m) 2) space complexity O(1) where m is  the length of pattern. The searching phase time complexity takes 1)  O(m+α ) in average case 2) O(n/m) in the best case and 3) O(n) in  the worst case, where α is the number of comparing leading to  mismatch and n is the length of input text.

Keywords: String matching, inverted list, inverted index, pattern, algorithm.

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Authors: Bharathi P. T, P. Subashini

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Ice cover County has a significant impact on rivers as it affects with the ice melting capacity which results in flooding, restrict navigation, modify the ecosystem and microclimate. River ices are made up of different ice types with varying ice thickness, so surveillance of river ice plays an important role. River ice types are captured using infrared imaging camera which captures the images even during the night times. In this paper the river ice infrared texture images are analysed using first-order statistical methods and secondorder statistical methods. The second order statistical methods considered are spatial gray level dependence method, gray level run length method and gray level difference method. The performance of the feature extraction methods are evaluated by using Probabilistic Neural Network classifier and it is found that the first-order statistical method and second-order statistical method yields low accuracy. So the features extracted from the first-order statistical method and second-order statistical method are combined and it is observed that the result of these combined features (First order statistical method + gray level run length method) provides higher accuracy when compared with the features from the first-order statistical method and second-order statistical method alone.

Keywords: Gray Level Difference Method, Gray Level Run Length Method, Kurtosis, Probabilistic Neural Network, Skewness, Spatial Gray Level Dependence Method.

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Authors: R. S. A. Nesbitt, J. Macione, A. Debroy, S. P. Kotha

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Bones are dynamic and responsive organs, they regulate their strength and mass according to the loads which they are subjected. Because, the Wnt/β-catenin pathway has profound effects on the regulation of bone mass, we hypothesized that mechanical loading of bone cells stimulates Wnt/β-catenin signaling, which results in the generation of new bone mass. Mechanical loading triggers the secretion of the Wnt molecule, which after binding to transmembrane proteins, causes GSK-3β (Glycogen synthase kinase 3 beta) to cease the phosphorylation of β-catenin. β-catenin accumulation in the cytoplasm, followed by its transport into the nucleus, binding to transcription factors (TCF/LEF) that initiate transcription of genes related to bone formation. To test this hypothesis, we used TOPGAL (Tcf Optimal Promoter β-galactosidase) mice in an experiment in which cyclic loads were applied to the forearm. TOPGAL mice are reporters for cells effected by the Wnt/β-catenin signaling pathway. TOPGAL mice are genetically engineered mice in which transcriptional activation of β- catenin, results in the production of an enzyme, β-galactosidase. The presence of this enzyme allows us to localize transcriptional activation of β-catenin to individual cells, thereby, allowing us to quantify the effects that mechanical loading has on the Wnt/β-catenin pathway and new bone formation. The ulnae of loaded TOPGAL mice were excised and transverse slices along different parts of the ulnar shaft were assayed for the presence of β-galactosidase. Our results indicate that loading increases β-catenin transcriptional activity in regions where this pathway is already primed (i.e. where basal activity is already higher) in a load magnitude dependent manner. Further experiments are needed to determine the temporal and spatial activation of this signaling in relation to bone formation.

Keywords: Bone Resorption and Formation, Mechanical Loading of Bone, Wnt Signaling Pathway & β-catenin.

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Authors: Maha Jameal Balgoon, Gehan A. Raouf, Safaa Y. Qusti, Soad Shaker Ali

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The main cause of Alzheimer disease (AD) was believed to be mainly due to the accumulation of free radicals owing to oxidative stress (OS) in brain tissue. The mechanism of the neurotoxicity of Aluminum chloride (AlCl3) induced AD in hippocampus Albino wister rat brain tissue, the curative & the protective effects of Lipidium sativum group (LS) water extract were assessed after 8 weeks by attenuated total reflection spectroscopy ATR-IR and histologically by light microscope. ATR-IR results revealed that the membrane phospholipid undergo free radical attacks, mediated by AlCl3, primary affects the polyunsaturated fatty acids indicated by the increased of the olefinic -C=CH sub-band area around 3012 cm-1 from the curve fitting analysis. The narrowing in the half band width (HBW) of the sνCH2 sub-band around 2852 cm-1 due to Al intoxication indicates the presence of trans form fatty acids rather than gauch rotomer. The degradation of hydrocarbon chain to shorter chain length, increasing in membrane fluidity, disorder, and decreasing in lipid polarity in AlCl3 group indicated by the detected changes in certain calculated area ratios compared to the control. Administration of LS was greatly improved these parameters compared to the AlCl3 group. Al influences the Aβ aggregation and plaque formation, which in turn interferes to and disrupts the membrane structure. The results also showed a marked increase in the β-parallel and antiparallel structure, that characterize the Aβ formation in Al-induced AD hippocampal brain tissue, indicated by the detected increase in both amide I sub-bands around 1674, 1692 cm-1. This drastic increase in Aβ formation was greatly reduced in the curative and protective groups compared to the AlCl3 group and approached nearly the control values. These results supported too by the light microscope. AlCl3 group showed significant marked degenerative changes in hippocampal neurons. Most cells appeared small, shrieked and deformed. Interestingly, the administration of LS in curative and protective groups markedly decreases the amount of degenerated cells compared to the non-treated group. In addition, the intensity of congo red stained cells was decreased. Hippocampal neurons looked more/or less similar to those of control. This study showed a promising therapeutic effect of Lipidium sativum group (LS) on AD rat model that seriously overcome the signs of oxidative stress on membrane lipid and restore the protein misfolding.

Keywords: Aluminum chloride, Alzheimer’s disease, ATR-IR, Lipidium sativum.

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Authors: Victor E. Gromov, Yurii F. Ivanov, Vadim B. Kosterev, Sergey V. Konovalov, Veronica I. Myasnikova, Guoyi Tang

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A study of the H-beam's nanosize structure phase states after thermomechanical strengthening was carried out by TEM. The following processes were analyzed. 1. The dispersing of the cementite plates by cutting them by moving dislocations. 2. The dissolution of cementite plates and repeated precipitation of the cementite particles on the dislocations, the boundaries, subgrains and grains. 3. The decay of solid solution of carbon in the α-iron after "self-tempering" of martensite. 4. The final transformation of the retained austenite in beinite with α-iron particles and cementite formation. 5. The implementation of the diffusion mechanism of γ ⇒ α transformation.

Keywords: nanosize, phase, steel, strengthening

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Authors: Daniel Badulescu

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Under the difficult access to finance of SMEs, they expect that its relationship with the banks shall constitute a real help to access appropriate financing, at reasonable costs and requirements, given the possibility of mutually beneficial and long lasting relation. The literature, but also the research we have carried on, is centered on such determinants as concentration and the length of the relationship, but at the same time, there is little certainty that banks are responding positively to them. Furthermore, although the trust is considered as being a fundamental element of bank relationship – see the case house bank – SMEs find that the banks finance them looking rather on collaterals and covenants than to trust. Moreover, a positive behavior, such as prompt or advance repayments of loans, doesn-t generate any positive feedback from the banks side. All these show a deep un-satisfaction of the SMEs concerning their relationship banking.

Keywords: Banks' behavior, relationship banking, SMEs.

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Authors: Masaki Ohno, Cervinia Manalo, Tetsuji Okuda, Satoshi Nakai, Wataru Nishijima

Abstract:

Reverse osmosis (RO) membranes have been widely used for desalination to purify water for drinking and other purposes. Although at present most RO membranes have no resistance to chlorine, chlorine-resistant membranes are being developed. Therefore, direct chlorine treatment or chlorine washing will be an option in preventing biofouling on chlorine-resistant membranes. Furthermore, if particle accumulation control is possible by using chlorine washing, expensive pretreatment for particle removal can be removed or simplified. The objective of this study was to determine the effective hypochlorite washing condition required for controlling biofilm formation and inorganic particle accumulation on RO membrane in a continuous flow channel with RO membrane and spacer. In this study, direct chlorine washing was done by soaking fouled RO membranes in hypochlorite solution and fluorescence intensity was used to quantify biofilm on the membrane surface. After 48 h of soaking the membranes in high fouling potential waters, the fluorescence intensity decreased to 0 from 470 using the following washing conditions: 10 mg/L chlorine concentration, 2 times/d washing interval, and 30 min washing time. The chlorine concentration required to control biofilm formation decreased as the chlorine concentration (0.5–10 mg/L), the washing interval (1–4 times/d), or the washing time (1–30 min) increased. For the sample solutions used in the study, 10 mg/L chlorine concentration with 2 times/d interval, and 5 min washing time was required for biofilm control. The optimum chlorine washing conditions obtained from soaking experiments proved to be applicable also in controlling biofilm formation in continuous flow experiments. Moreover, chlorine washing employed in controlling biofilm with suspended particles resulted in lower amounts of organic (0.03 mg/cm²) and inorganic (0.14 mg/cm²) deposits on the membrane than that for sample water without chlorine washing (0.14 mg/cm² and 0.33 mg/cm², respectively). The amount of biofilm formed was 79% controlled by continuous washing with 10 mg/L of free chlorine concentration, and the inorganic accumulation amount decreased by 58% to levels similar to that of pure water with kaolin (0.17 mg/cm²) as feed water. These results confirmed the acceleration of particle accumulation due to biofilm formation, and that the inhibition of biofilm growth can almost completely reduce further particle accumulation. In addition, effective hypochlorite washing condition which can control both biofilm formation and particle accumulation could be achieved.

Keywords: Biofouling control, hypochlorite, reverse osmosis, washing condition optimization.

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Authors: Münüre Tanur Erkoyuncu, Mustafa Yorgancılar

Abstract:

Crop improvement through genetic engineering depends on effective and reproducible plant regeneration systems. Immature embryos are the most widely used explant source for in vitro regeneration in barley (Hordeum vulgare L.). However, immature embryos require the continuous growth of donor plants and the suitable stage for their culture is also certainly limited. On the other hand, mature embryos can be procured and stored easily; they can be studied throughout the year. In this study, an effective callus induction and plant regeneration were aimed to develop from mature embryos of different barley genotypes. The effect of medium (MS₁ and MS₂), auxin type (2,4-D, dicamba, picloram and 2,4,5-T) and concentrations (2, 4, 6 mg/l) on callus formation and effect of cytokinin type (TDZ, BAP) and concentrations (0.2, 0.5, 1.0 mg/l) on green plant regeneration were evaluated in mature embryo culture of barley. Callus and shoot formation was successful for all genotypes. By depending on genotype, MS₁ is the best medium, 4 mg/l dicamba is the best growth regulator in the callus induction and MS₁ is the best medium, 1 mg/l BAP is the best growth regulator in the shoot formation were determined.

Keywords: Barley, callus, embryo culture, mature embryo.

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