Search results for: fractional edge domination number

Authors: El-Ghalia Filali, Cherif Gadouche, Mohamed Tahar

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A three-dimensional numerical simulation of flow through mini and microchannels with designed roughness is conducted here. The effect of the roughness height (surface roughness), geometry, Reynolds number on the friction factor and the Nusselt number is investigated. The study is carried out by employing CFD software, CFX. Our work focuses on a water flow inside a circular mini-channel of 1 mm and microchannels of 500 and 100 μm in diameter. The speed entry varies from 0.1 m/s to 20 m/s. The general trend can be observed that bigger sizes of roughness element lead to higher flow resistance. It is found that the friction factor increases in a nonlinear fashion with the increase in obstruction height. Particularly, the effect of roughness can no longer be ignored at relative roughness height higher than 3%. A significant increase in Poiseuille number is detected for all configurations considered. The same observation can be done for Nusselt number. The transition zone between laminar and turbulent flow depends on the channel diameter.

Keywords: hydrodynamics, heat transfer, minichannel, microchannel, roughness

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Authors: Arun Kumar R. K. Gothra, Hasan Alhakamy

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With increasing expectations and demands for warehousing and distribution, Warehouse Solution Incorporated in Victoria has been looking at ways to improve on its business processes to maintain the competitive edge. To maintain the provision of high quality service standards at competitive and affordable prices, improvements in the logistics management are necessary. One such avenue is to make efficient use of space available in the warehouse. This paper is based on a study of the collaboration of Warehouse Solution Inc with Dandenong Distribution Centre (DDC) to solve congestion problem and enhance efficiency of the whole warehouse activities.

Keywords: space optimization, optimal utilization, warehouse, DDC

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Authors: Dia I. Abu-Al-Nadi, M. J. Mismar, T. H. Ismail

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A technique for estimating the direction-of-arrival (DOA) of unknown number of source signals is presented using the eigen-approach. The eigenvector corresponding to the minimum eigenvalue of the autocorrelation matrix yields the minimum output power of the array. Also, the array polynomial with this eigenvector possesses roots on the unit circle. Therefore, the pseudo-spectrum is found by perturbing the phases of the roots one by one and calculating the corresponding array output power. The results indicate that the DOAs and the number of source signals are estimated accurately in the presence of a wide range of input noise levels.

Keywords: array signal processing, direction-of-arrival, antenna arrays, Eigenvalues, Eigenvectors, Lagrange multiplier

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Authors: Nirmal Kant Singh, Anshuman Pratap Singh

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In this study the augmentation of heat transfer in a channel with delta winglet type vortex generators is evaluated. Three-dimensional numerical simulations are performed in a rectangular channel with longitudinal triangular vortex generators (LVGs). The span wise averaged Nusselt number and mean temperature are compared with and without vortex generators in the channel. The effect of variation of blade angle (15°, 30°, 45°, and 60°) is studied at a Reynolds number of 10000. The numerical results indicate that the application of LVGs effectively enhances heat transfer in the channel. The Nusselt number and mean outlet temperature were found to be greater using LVGs than in the channel without LVGs. It is observed that heat transfer increases with increase in blade angle at the same Reynolds number.

Keywords: heat transfer, rectangular channel, longitudinal vortex generators, effect of blade angle

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Authors: Hilly Moodrick-Even Khen

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This study analyzes the legal regulation of the use of force in international law in the context of three emerging Palestinian forms of struggle against Israeli occupation: the Knife Intifada, Gaza border disturbances, and the launching of incendiary kites. It discusses what legal paradigms or concepts should regulate the type and level of force used in each situation—a question that is complicated by various dilemmas—and appraises the Israel Defence Forces policies tailored in response. Methodologically, the study is based on analysis of scholarship on the conceptual legal issues as well as dicta of the courts. It evaluates the applicability of two legal paradigms regulating the use of force in military operations—(i) the conduct of hostilities and (ii) law enforcement—as well as the concept of self-defense in international law and the escalation of force procedure. While the “Knife Intifada” clearly falls under the law enforcement paradigm, the disturbances at the border and the launching of incendiary kites raise more difficult questions, as applying law enforcement, especially in the latter case, can have undesirable ramifications for safeguarding humanitarian interests. The use of force in the cases of the border disturbances and the incendiary kites should thus be regulated, mutatis mutandis, by the concept of self-defense and escalation of force procedures; and in the latter case, the hostilities paradigm can also be applied. The study provides a factual description and analysis of the background and nature of the forms of struggle in Gaza and the West Bank—in each case surveying the geo-political developments since operation Protective Edge, contextualizing how the organized and unorganized violent activities evolved, and analyzing them in terms of level of organization and intensity. It then presents the two paradigms of the use of force—law enforcement and conduct of hostilities—and the concept of self-defense. Lastly, it uses the factual findings as the basis for legally analyzing which paradigm or concept regulating the use of force applies for each form of struggle. The study concludes that in most cases, the concept of self-defense is preferable to the hostilities or the law enforcement paradigms, as it best safeguards humanitarian interests and ensures the least loss of civilian lives.

Keywords: Israeli-Palestinian conflict, self defense, terrorism, use of force

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Authors: H. E. M. W. G. M. K. Ekanayake, J. Dharmasena

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Natural Landscape fragmentation and habitat loss are emerging issues in Sri Lanka, which is due to rapid urban development and inadequate concern of managing Landscape connectivity. Urban Wetlands are the most vulnerable ecosystem effects from the fragmentation. Therefore, management of landscape connectivity with proper analysis and understanding has become a most important measure for urban wetland habitats. This study aimed to introduce spatial planning strategy to identify and locate landscape developments appropriately in order to restore landscape connectivity. Therefore, the study focuses on understanding the relationship between habitat patch metrics and landscape connectivity with reference to Colombo wetlands. Geographic Information Systems (GIS) was used to measure the wetland patch metrics; Patch area, Total edge, Perimeter-area ratio, Core area index and Inter-patch distances. Further, GIS-enabled least-cost path tool was used to measure the Landscape connectivity and calculate the number of species flow paths per wetland patch. According to the research findings; increasing the patch area, maintaining a mean perimeter-area ratio and core area index also reducing the inter-patch distances could enhance the landscape connectivity. Further, this study introduces three patch typologies; ‘active patches,' ‘open patches’ and ‘closed patches’ that severs to landscape connectivity in different levels. In the end, the study proposes a strategy for Landscape Architects to select most suitable locations to implement ecological based landscape developments with adjacent to the existing urban habitat in order to enhance habitat patch metrics and to restore the landscape connectivity.

Keywords: landscape fragmentation, urban wetlands, landscape connectivity, patch metrics

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Authors: Mohammed Abdullah Alrajhi

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The rapid growth in the number of mobile phone subscribers has resulted in an increased number of mobile base stations all over the world. Generally, mobile base stations are existing in huge numbers in populated areas than in non-populated ones to serve the largest number of users. The total number of mobile subscriptions in the Kingdom of Saudi Arabia reached around 50 million at the end of 2014, with a penetration rate of 165.1% according to the quarterly electronic newsletter issued by the Communications and Information Technology Commission. The current investigation was conducted primarily to measure the level of electromagnetic fields emitted from 400 mobile base stations for the purpose of environmental safety and radiation protection in light of national guidelines for public exposure as well as the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The outcomes of this investigation provide valuable comments and recommendation for safety and protection of electromagnetic fields emitted from mobile base stations.

Keywords: electromagnetic fields, mobile, safety, protection, ICNIRP

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Authors: Wesam Ali

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This paper provides useful guidelines to the circuit designers on the magnitude of fabrication errors in multilayer millimeter-wave components that are acceptable and presents data not previously reported in the literature. A particularly significant error that was quantified was that of skew between conductors on different layers, where it was found that a skew angle of only 0.1° resulted in very significant changes in bandwidth and insertion loss. The work was supported by a detailed investigation on a 35GHz, multilayer edge-coupled band-pass filter, which was fabricated on alumina substrates using photoimageable thick film process.

Keywords: fabrication errors, multilayer, high frequency band, photoimagable technology

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Authors: D. Srinivasacharya, G. Madhava Rao

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In this article, the pulsatile flow of blood flow in bifurcated artery with mild stenosis is investigated. Blood is treated to be a micropolar fluid with constant density. The arteries forming bifurcation are assumed to be symmetric about its axes and straight cylinders of restricted length. As the geometry of the stenosed bifurcated artery is irregular, it is changed to regular geometry utilizing the appropriate transformations. The numerical solutions, using the finite difference method, are computed for the flow rate, the shear stress, and the impedance. The influence of time, coupling number, half of the bifurcated angle and Womersley number on shear stress, flow rate and impedance (resistance to the flow) on both sides of the flow divider is shown graphically. It has been observed that the shear stress and flow rate are increasing with increase in the values of Womersley number and bifurcation angle on both sides of the apex. The shear stress is increasing along the inner wall and decreasing along the outer wall of the daughter artery with an increase in the value of coupling number. Further, it has been noticed that the shear stress, flow rate, and impedance are perturbed largely near to the apex in the parent artery due to the presence of backflow near the apex.

Keywords: micropolar fluid, bifurcated artery, stenosis, back flow, secondary flow, pulsatile flow, Womersley number

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Authors: Rossana Taravella, Gilberto M. Cellura, Giuseppe Cirrincione, Salvatore Asciutto, Marco Caruso, Massimo Benedetto, Renato Ciofalo, Giuliana Pace, Salvatore Novo

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Objectives: This retrospective analysis sought to evaluate 1-month outcomes and therapy effectiveness of a population of patients treated with MitraClip therapy. We describe in this article the preliminary results of primary effectiveness endpoint. Background: Percutaneous Mitral Repair is being developed to treat severe mitral regurgitation (MR), with increasing real-world cases of functional MR (FMR). In the EVEREST (Endovascular Valve Edge-to-Edge Repair Study)II trial, the percutaneous device showed superior safety but less reduction in MR at 1year. 4-year outcomes from EVEREST II trial showed no difference in the prevalence of moderate-severe and severe MR or mortality at 4years between surgical mitral repair and percutaneous approach. Methods: We analysed retrospectively collected data from one center experience in Italy enrolled from January 2011 to December 2016. The study included 62 patients [mean age 74±11years, 43 men (69%)] with MR of at least grade3+. Most of the patients had functional MR, were in New York Heart Association (NYHA) functional class III or IV, with a large portion (78%) of mild-to-moderate Tricuspid Regurgitation (TR). One or more clips were implanted in 67 procedures (62 patients). Results and Conclusions: Severity of MR was reduced in all successfully treated patients,54(90%) were discharged with MR≤2+ (primary effectiveness endpoint). Clinical 1-month follow-up data showed an improvement in NYHA functional class (42 patients (70%) in NYHA class I-II). 60 of 62 (97 %) successfully treated patients were free from death and mitral valve surgery at 1-month follow-up. MitraClip therapy reduces functional MR with acute MR reduction to <2+ in the great majority of patients, with a large freedom from death, surgery or recurrent MR in a great portion of patients.

Keywords: MitraClip, mitral regurgitation, heart valves, catheter-based therapy

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Authors: Jasvinder Singh, Manjinder Singh

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Welding of dissimilar materials is a complicated process due to the difference in melting point of two materials. Thermal conductivity and coefficient of thermal expansion of dissimilar materials also different; therefore, residual stresses produced in the weldment and base metal are the most critical problem associated with the joining of dissimilar materials. Tensile strength and impact toughness also reduced due to the residual stresses. In the present research work, an attempt has been made to weld SS304 and MS1018 dissimilar materials by submerged arc welding (SAW). By conducting trail, runs most effective parameters welding current, Arc voltage, welding speed and nozzle to plate distance were selected to weld these materials. The fractional factorial technique was used to optimize the welding parameters. Effect on tensile strength (TS), fracture toughness (FT) and microhardness of weldment were studied. It was concluded that by optimizing welding current, voltage and welding speed the properties of weldment can be enhanced.

Keywords: SAW, Tensile Strength (TS), fracture toughness, micro hardness

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Authors: Abdulatif Abdulsalam Mohamed Shaban

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A.C motors, in general, have superior performance characteristics to their d.c. counterparts. However, despite these advantage a.c. motors lack the controllability and simplicity and so d.c. motors retain a competitive edge where precise control is required. As part of an overall project to develop an improved cycloconverter control strategy for induction motors. Simulation and modelling techniques have been developed. This contribution describes a method used to simulate an induction motor drive using the SIMULINK toolbox within MATLAB software. The cycloconverter fed induction motor is principally modelled using the d-q axis equations. Results of the simulation for a given set of induction motor parameters are also presented.

Keywords: simulation, converter, motor, cycloconverter

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Authors: Thaline Maira P. Cruz, Debora B. Moretti, Wiolene M. Nordi, José Eurico P. Cyrino, Raul Machado-Neto

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The aim of this study was to evaluate the effect of lyophilized bovine colostrum (LBC) used as partial source of dietary protein on the histological characteristics of the intestinal epithelium of juvenile dourado (Salminus brasiliensis). Juveniles were fed with diets containing 0, 10 or 20% of lyophilized bovine colostrum (LBC) inclusion for either 30 or 60 days. For the histological study, the intestine was divided into three segments, S1, S2 and posterior intestine. In the S1 segment, interaction between treatment and period was observed in the number of goblet cells containing sialomucin, effect of treatment in the total number of goblet cells and effect of period in the number of goblet cells containing sulphomucins (P<0.05). In the S2 segment, effect of period was observed in the number of goblet cells containing acid, neutral and total mucins, sialomucins and Vv (P<0.05). In the posterior intestine, effect of period was observed in the thickness of muscle layer and number of goblet cells containing sialomucins and sulphomucins (P<0.05). Considering the aspects studied, the presence of lyophilized bovine colostrum in the diet did not significantly influence the enteric histological characteristics of juvenile dourado during the period of the study.

Keywords: carnivorous fish, goblet cells, mucins, teleost

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Authors: Erwin San Juan Martinez, Miguel Angel Aguilar Mendez, Manuel Sandoval Villa, Libia Iris Trejo Tellez

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Some nanomaterials may improve the vegetal growth in certain concentration intervals, and could be used as nanofertilizers in order to increase crops yield, and decreasing the environmental pollution due to non-controlled use of conventional fertilizers, therefore the present investigation’s objective was to synthetize and characterize gelatin nanoparticles loaded with calcium generated through pulverization technique and be used as nanofertilizers. To obtain these materials, a fractional factorial design 27-4 was used in order to evaluate the largest number of factors (concentration of Ca2+, temperature and agitation time of the solution and calcium concentration, drying temperature, and % spray) with a possible effect on the size, distribution and morphology of nanoparticles. For the formation of nanoparticles, a Nano Spray-Dryer B - 90® (Buchi, Flawil, Switzerland), equipped with a spray cap of 4 µm was used. Size and morphology of the obtained nanoparticles were evaluated using a scanning electron microscope (JOEL JSM-6390LV model; Tokyo, Japan) equipped with an energy dispersive x-ray X (EDS) detector. The total quantification of Ca2+ as well as its release by the nanoparticles was carried out in an equipment of induction atomic emission spectroscopy coupled plasma (ICP-ES 725, Agilent, Mulgrave, Australia). Of the seven factors evaluated, only the concentration of fertilizer, % spray and concentration of polymer presented a statistically significant effect on particle size. Micrographs of SEM from six of the eight conditions evaluated in this research showed particles separated and with a good degree of sphericity, while in the other two particles had amorphous morphology and aggregation. In all treatments, most of the particles showed smooth surfaces. The average size of smallest particle obtained was 492 nm, while EDS results showed an even distribution of Ca2+ in the polymer matrix. The largest concentration of Ca2+ in ICP was 10.5%, which agrees with the theoretical value calculated, while the release kinetics showed an upward trend within 24 h. Using the technique employed in this research, it was possible to obtain nanoparticles loaded with calcium, of good size, sphericity and with release controlled properties. The characteristics of nanoparticles resulted from manipulation of the conditions of synthesis which allow control of the size and shape of the particles, and provides the means to adapt the properties of the materials to an specific application.

Keywords: calcium, controlled release, gelatin, nano spraydryer, nanofertilizer

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Authors: Rasha Ali Dheyab, Edurad Vlad

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Migration is associated with other important global issues, including development, poverty, and human rights. Migrants are often the most dynamic members of society; historically, migration has supported economic development and the rise of nations and enriched cultures. It also presents significant challenges. The word ‘racism’ is not just about beliefs or statements; it also contains the ability to force those beliefs or world views as hegemonic and as a basis for the refusal of rights or equality. For this reason, racism is embedded in power relations of different types. Racism is not only an awareness of distinction and groups, but it also has extremely practical roles in maintaining: First, inequitable social power arrangements; and second, racist behavioral manifestations such as verbal rejection, avoidance, discrimination, physical attack, and elimination. The focus is on aspects of racism in the media to deal with the migration phenomenon. The reproduction and promotion of racism by certain areas of the media is not a simple and straightforward process. It is important to see how the media serves in the reproduction of racism. This article shows attitudes to migration as they have appeared in British periodicals over the last few years. One might conclude that the reproduction of racism by the media is not a simple and straightforward process. It has become obvious that the role of the media in the reproduction of racism is inextricably linked to the general characteristics of racism and white domination in society, particularly the structural and ideological structuring of that kind of group power. This highlights the press's function as a business, social, and cultural institution. The press has to be examined in connection to the institutions of the economic and political as well.

Keywords: British periodicals, culture studies, migration, racism

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Authors: Shih-Yan Chen, Shin-Shin Kao

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In this paper, a thorough review about dual-cubes, DCn, the related studies and their variations are given. DCn was introduced to be a network which retains the pleasing properties of hypercube Qn but has a much smaller diameter. In fact, it is so constructed that the number of vertices of DCn is equal to the number of vertices of Q2n +1. However, each vertex in DCn is adjacent to n + 1 neighbors and so DCn has (n + 1) × 2^2n edges in total, which is roughly half the number of edges of Q2n+1. In addition, the diameter of any DCn is 2n +2, which is of the same order of that of Q2n+1. For selfcompleteness, basic definitions, construction rules and symbols are provided. We chronicle the results, where eleven significant theorems are presented, and include some open problems at the end.

Keywords: dual-cubes, dual-cube extensive networks, dual-cube-like networks, hypercubes, fault-tolerant hamiltonian property

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Authors: T. T. Naas, Y. Lasbet, C. Kezrane

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The thermal control in many systems is widely accomplished applying mixed convection process due to its low cost, reliability and easy maintenance. Typical applications include the aircraft electronic equipment, rotating-disc heat exchangers, turbo machinery, and nuclear reactors, etc. Natural convection in an inclined square enclosure heated via wall heater has been studied numerically. Finite volume method is used for solving momentum and energy equations in the form of stream function–vorticity. The right and left walls are kept at a constant temperature, while the other parts are adiabatic. The range of the inclination angle covers a whole revolution. The method is validated for a vertical cavity. A general power law dependence of the Nusselt number with respect to the Rayleigh number with the coefficient and exponent as functions of the inclination angle is presented. For a fixed Rayleigh number, the inclination angle increases or decreases is found.

Keywords: natural convection in enclosure, inclined enclosure, Nusselt number, entropy generation analyze

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Authors: Feyza Eda Akyurek, Bayram Sahin, Kadir Gelis, Eyuphan Manay, Murat Ceylan

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Turbulent forced convection heat transfer and pressure drop characteristics of Al₂O₃–water nanofluid flowing through a concentric tube heat exchanger with and without coiled wire turbulators were studied experimentally. The experiments were conducted in the Reynolds number ranging from 4000 to 20000, particle volume concentrations of 0.8 vol.% and 1.6 vol.%. Two turbulators with the pitches of 25 mm and 39 mm were used. The results of nanofluids indicated that average Nusselt number increased much more with increasing Reynolds number compared to that of pure water. Thermal conductivity enhancement by the nanofluids resulted in heat transfer enhancement. Once the pressure drop of the alumina/water nanofluid was analyzed, it was nearly equal to that of pure water at the same Reynolds number range. It was concluded that nanofluids with the volume fractions of 0.8 and 1.6 did not have a significant effect on pressure drop change. However, the use of wire coils in heat exchanger enhanced heat transfer as well as the pressure drop.

Keywords: turbulators, heat exchanger, nanofluids, heat transfer enhancement

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Authors: Hamidreza Bayat, Arash Mirabdolah Lavasani, Meysam Bolhasani, Sajad Moosavi

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Heat transfer from flat tube is studied numerically. Reynolds number is defined base on equivalent circular tube which is varied in range of 100 to 300. In these range of Reynolds number flow is considered to be laminar, unsteady, and incompressible. Equations are solved by using finite volume method. Results show that increasing l/D from 1 to 2 has insignificant effect on heat transfer and Nusselt number of flat tube is slightly lower than circular tube. However, thermal-hydraulic performance of flat tube is up to 2.7 times greater than circular tube.

Keywords: laminar flow, flat tube, convective heat transfer, heat exchanger

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Authors: Pratibha, Jyoti Kori

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Particles in industry, harvesting, coal mines, etc. may not necessarily be spherical in shape. In general, it is difficult to find perfectly spherical particle. The prediction of movement and deposition of non spherical particle in distinct airway generation is much more difficult as compared to spherical particles. Moreover, there is extensive inflexibility in deposition between ducts of a particular generation and inside every alveolar duct since particle concentrations can be much bigger than the mean acinar concentration. Consequently, a large number of particles fail to be exhaled during expiration. This study presents a mathematical model for the movement and deposition of those non-spherical particles by using particle aspect ratio and shape factor. We analyse the pulsatile behavior underneath sinusoidal wall oscillation due to periodic breathing condition through a non-Darcian porous medium or inside pulmonary region. Since the fluid is viscous and Newtonian, the generalized Navier-Stokes equation in two-dimensional coordinate system (r, z) is used with boundary-layer theory. Results are obtained for various values of Reynolds number, Womersley number, Forchsheimer number, particle aspect ratio and shape factor. Numerical computation is done by using finite difference scheme for very fine mesh in MATLAB. It is found that the overall air velocity is significantly increased by changes in aerodynamic diameter, aspect ratio, alveoli size, Reynolds number and the pulse rate; while velocity is decreased by increasing Forchheimer number.

Keywords: deposition, interstitial lung diseases, non-Darcian medium, numerical simulation, shape factor

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Authors: Tanapon Suklim, Prachaya Intaphrom, Noppadol Poomvises, Anchalee Kongsuk

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The relationship between shear wave velocity (Vs30) and blow count Number from Standard Penetration Tests (NSPT) was investigated on specified embankment dam to find the solution which can be used to estimate the value of N. Shear wave velocity, Vs30 and blow count number, NSPT were performed at three specified dam sites. At each site, Vs30 measurement was recorded by using seismic survey of MASW technique and NSPT were measured by field Standard Penetration Test. Regression analysis was used to derive statistical relation. The relation is giving a final solution to applicable calculated N-value with other earthen dam. Dam engineer can use the statistical relation to convert field Vs30 to estimated N-value instead of absolute N-value from field Standard Penetration Test. It can be noted that the formulae can be applied only in the earthen dam of specified material.

Keywords: blow count number, earthen dam, embankment, shear wave velocity

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Authors: Krishnendra Shekhawat

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Given a graph G = (V, E), a rectangular dual of G represents the vertices of G by a set of interior-disjoint rectangles such that two rectangles touch if and only if there is an edge between the two corresponding vertices in G. Rectangular duals do not exist for every graph, so we can define maximal rectangular duals. A maximal rectangular dual is a rectangular dual of a graph G such that there exists no graph G ′ with a rectangular dual where G is a subgraph of G ′. In this paper, we enumerate all maximal rectangular duals (or, to be precise, the corresponding planar graphs) up to six nodes and presents a necessary condition for the existence of a rectangular dual. This work allegedly has applications in integrated circuit design and architectural floor plans.

Keywords: adjacency, degree sequence, dual graph, rectangular dual

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Authors: R. M. Kashim

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The study investigated primary school teachers’ conceptual and procedural knowledge of rational numbers and its effects on pupil’s achievement in rational numbers. Specifically, primary school teachers’ level of conceptual knowledge about rational numbers, primary school teachers’ level of procedural knowledge about rational numbers, and the effects of teachers conceptual and procedural knowledge on their pupils understanding of rational numbers in primary schools is investigated. The study was carried out in Bauchi metropolis in the Bauchi state of Nigeria. The design of the study was a multi-stage design. The first stage was a descriptive design. The second stage involves a pre-test, post-test only quasi-experimental design. Two instruments were used for the data collection in the study. These were Conceptual and Procedural knowledge test (CPKT) and Rational number achievement test (RAT), the population of the study comprises of three (3) mathematics teachers’ holders of Nigerian Certificate in Education (NCE) teaching primary six and 210 pupils in their intact classes were used for the study. The data collected were analyzed using mean, standard deviation, analysis of variance, analysis of covariance and t- test. The findings indicated that the pupils taught rational number by a teacher that has high conceptual and procedural knowledge understand and perform better than the pupil taught by a teacher who has low conceptual and procedural knowledge of rational number. It is, therefore, recommended that teachers in primary schools should be encouraged to enrich their conceptual knowledge of rational numbers. Also, the superiority performance of teachers in procedural knowledge in rational number should not become an obstruction of understanding. Teachers Conceptual and procedural knowledge of rational numbers should be balanced so that primary school pupils will have a view of better teaching and learning of rational number in our contemporary schools.

Keywords: conceptual, procedural knowledge, rational number, pupils

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Authors: Souhir Ben Amor, Heni Boubaker, Lotfi Belkacem

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This aims of this paper is to forecast the electricity spot prices. First, we focus on modeling the conditional mean of the series so we adopt a generalized fractional -factor Gegenbauer process (k-factor GARMA). Secondly, the residual from the -factor GARMA model has used as a proxy for the conditional variance; these residuals were predicted using two different approaches. In the first approach, a local linear wavelet neural network model (LLWNN) has developed to predict the conditional variance using the Back Propagation learning algorithms. In the second approach, the Gegenbauer generalized autoregressive conditional heteroscedasticity process (G-GARCH) has adopted, and the parameters of the k-factor GARMA-G-GARCH model has estimated using the wavelet methodology based on the discrete wavelet packet transform (DWPT) approach. The empirical results have shown that the k-factor GARMA-G-GARCH model outperform the hybrid k-factor GARMA-LLWNN model, and find it is more appropriate for forecasts.

Keywords: electricity price, k-factor GARMA, LLWNN, G-GARCH, forecasting

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Authors: Hamed K. Arzani, Hamid K. Arzani, S.N. Kazi, A. Badarudin

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Numerical investigation into convective heat transfer of CuO-Water based nanofluid in a pipe with return bend under laminar flow conditions has been done. The impacts of Reynolds number and the volume concentration of nanoparticles on the flow and the convective heat transfer behaviour are investigated. The results indicate that the increase in Reynolds number leads to the enhancement of average Nusselt number, and the increase in specific heat in the presence of the nanofluid results in improvement in heat transfer. Also, the presence of the secondary flow in the curve plays a key role in increasing the average Nusselt number and it appears higher than the inlet and outlet tubes. However, the pressure drop curve increases significantly in the tubes with the increase in nanoparticles concentration.

Keywords: laminar forced convection, curve pipe, return bend, nanufluid, CFD

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Authors: Qiong Hu, Ming Yue

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Language variation signals the newest usage of language community, which might become the developmental trend of that language. However, language textbooks cannot keep up with these emergent usages. Most Chinese English learners nowadays are still exposed to traditional grammar prescribed in the textbook so that some variational usages cannot be acquired. The personal pronoun we is prescribed as a plural pronoun in the textbook grammar, but its number value is more flexible in actual use. Based on the Chinese Learner English Corpus (CLEC), and with the homemade Friends corpus as reference, the present research explores the number value of the first person pronoun we used by Chinese English learners. With consideration of the subjectivity of we, this paper annotated the number value of all the wes in “we+ PCU (Perception-cognation-utterance) verbs” collocations. Results show that though exposed to traditional textbooks which prescribe the plural reference of we, there still exists some unconventional usage (singular or vague in reference) in the writings of Chinese English learners, which is less frequent than that of the native speeches. Corpus data and results from manual semantic annotation show that this could be due to the impact of formulaic sequence on the learners and the positive transfer from their native language. An improved SLA model of native language, target language and interlanguage is put forward to recognize the existence of variation in second language acquisition, which should be given more attention during teaching.

Keywords: Chinese English learners, number, PCU verbs, Personal pronoun we

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Authors: Narges Solaymani

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medical training of patients. Nursing is a very important profession in the societies of the world. Although in the past, all caregivers of the sick and disabled were called nurses, nowadays, a nurse is a person who has a university education in this field. There are nurses in bachelor's, master's, and doctoral degrees in nursing. New courses have been launched in the master's degree based on duty-oriented nurses. A nurse cannot have an independent treatment center but is a member of the treatment team in established treatment centers such as hospitals, clinics, or offices. Nurses can establish counseling centers and provide nursing services at home. According to the standards, the number of nurses should be three times the number of doctors or twice the number of hospital beds, or there should be three nurses for every thousand people. Also, international standards show that in the internal and surgical department, every 4 to 6 patients should have a nurse.

Keywords: Nurse, Intensive Care, CPR, Bandage

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Authors: Ali M. Alakeel

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Assertion-based software testing has been shown to be a promising tool for generating test cases that reveal program faults. Because the number of assertions may be very large for industry-size programs, one of the main concerns to the applicability of assertion-based testing is the amount of search time required to explore a large number of assertions. This paper presents a new approach for assertions exploration during the process of Assertion-Based software testing. Our initial exterminations with the proposed approach show that the performance of Assertion-Based testing may be improved, therefore, making this approach more efficient when applied on programs with large number of assertions.

Keywords: software testing, assertion-based testing, program assertions, generating test

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Authors: Mai Anh Pham Ho

Abstract:

Scarf products today is a symbol of fashion to decorate, to make our life more beautiful and bring new features to our living space. It also shows the cultural identity by using the traditional patterns that make easily to introduce the image of Vietnam to other nations all over the world. Therefore, the purpose of this research is to classify Vietnamese traditional patterns according to the era and dynasties. Vietnamese traditional patterns through the dynasties of Vietnamese history are done and classified by five groups of patterns including the geometric patterns, the natural patterns, the animal patterns, the floral patterns, and the character patterns in the Prehistoric times, the Bronze and Iron age, the Chinese domination, the Ngo-Dinh-TienLe-Ly-Tran-Ho dynasty, and the LeSo-Mac-LeTrinh-TaySon-Nguyen dynasty. Besides, there are some special kinds of Vietnamese traditional patterns like buffalo, lotus, bronze-drum, Phuc Loc Tho character, and so on. Extensive research was conducted for modernizing scarf collection applied Vietnamese traditional patterns which the fashion trend is used on creating works. The concept, target, image map, lifestyle map, motif, colours, arrangement and completion of patterns on scarf were set up. The scarf collection is designed and developed by the Adobe Illustrator program with three colour ways for each scarf. Upon completion of the research, digital printing technology is chosen for using on scarf collection which Vietnamese traditional patterns were researched deeply and widely with the purpose of establishment the basic background for Vietnamese culture in order to identify Vietnamese national personality as well as establish and preserve the cultural heritage.

Keywords: scarf collection, Vietnamese traditional patterns, printing methods, fabric design

Procedia PDF Downloads 342

Authors: Mochamad Beta Auditama, Yusuf Kurniawan

Abstract:

A smartphone or tablet require a strong randomness to establish secure encrypted communication, encrypt files, etc. Therefore, random number generation is one of the main keys to provide secrecy. Android devices are equipped with hardware-based sensors, such as accelerometer, gyroscope, etc. Each of these sensors provides a stochastic process which has a potential to be used as an extra randomness source, in addition to /dev/random and /dev/urandom pseudorandom number generators. Android sensors can provide randomness automatically. To obtain randomness from Android sensors, each one of Android sensors shall be used to construct an entropy source. After all entropy sources are constructed, output from these entropy sources are combined to provide more entropy. Then, a deterministic process is used to produces a sequence of random bits from the combined output. All of these processes are done in accordance with NIST SP 800-22 and the series of NIST SP 800-90. The operation conditions are done 1) on Android user-space, and 2) the Android device is placed motionless on a desk.

Keywords: Android hardware-based sensor, deterministic process, entropy source, random number generation/generators

Procedia PDF Downloads 374