The Existence Solution to the Development Wave Equation With Arbitrary Conditions

We study the development wave equation with some conditions and proving theexistence and uniqueness solution by using the reflection method .Keywords: Wave equation, Mathematica, reflection method

The effects of using variable lengths for degraded signal acquisition in GPS receivers

The signal acquisition in GPS receivers is the first and very crucial process that may affect the overall performance of a navigation receiver. Acquisition program initiates a searching operation on received navigation signals to detect and identify the visible satellites. However, signal acquisition becomes a very challenging task in a degraded environment (i.e, dense urban) and the receiver may not be able to detect the satellites present in radio-vicinity, thus cannot estimate an accurate position solution. In such environments, satellite signals are attenuated and fluctuated due to fading introduced by Multipath and NLOS reception. To perform signal acquisition in such degraded environments, larger data accumulation can be effective in enhancing SNR, which tradeoff huge computational load, prolonged acquisition time and high cost of receiver. This paper highlights the effects of fading on satellite signal acquisition in GPS receiver through variable data lengths and SNR comparison, and then develops a statistical relationship between satellite visibility and SNR. Furthermore it also analyzes/investigates the tradeoff between computation load and signal data length

Fabrication of a new photo-sensitized solar cell using TiO2\ZnO Nanocomposite synthesized via a modified sol-gel Technique

The current research synthesized was carried out using a modified solgel Technique for titanium dioxide ( TiO2) and zinc oxide (ZnO) nanocomposite. The morphology and optical properties of the synthesized nanocomposite were examined using a transmission electron microscope ( TEM) and UV-Visible spectroscopy. The structure of the synthesized nanocomposite was proved using X-ray Diffraction(XRD). The particle size of the ZnO/TiO2 nanocomposites was found to be range between 11 to 27.37 nm. The product of TEM has proof of the inclusion in the ZnO matrix of spherical TiO2particles. Also found were TiO2 sections attached to the ZnO-like rodlike particles., the ZnO/TiO2 Nanocomposites had better optical absorbing properties. The nanocomposite has been used to create a new photosensitizer solar cell with the efficiency of energy conversion of approximately 4.6%, using (E)-ethyl 4- ((4-nitrobenzylidene)) aminobenzoate as organic photo-sensitized (OPS) by (ITO/TiO2\ZnO nanocomposite/POS/iodine/silver (Ag) nanofilm/ITO)

The Issues in Which Sibawayh Made a Mistake in the Book ``Ea'arab of the Qur'an'' for An-Nahas/A Grammar Study

This study sheds light on the issues in which Sibawayh made a mistake in the book ``Ea'arab of the Qur'an'' for An-Nahas, a grammatical study, where I enumerated these issues and edited them by presenting and discussing the evidence and then concluded them with the opinion of the researchers, with a clear statement of misleading. All this stems from justice and truth, far from fanaticism or inclination toward one scholar without another. The research was divided into an introduction and a preface that included a brief translation of Mark Al-Nahas and a definition of confusion both linguistically and idiomatically, then the issues that Al-Nahas made mistakes in Sibawayh and the issues in which other scholars were mistakenly transferred to Sibawayh. Finally, a conclusion that included the most important results extracted from the research and a list of the most essential approved sources. Keywords: Al-Nahas, Sibawayh, mistake, mubrad, Basroun, Kufi

Natural convection in a square inclined enclosure with vee-corrugated sidewalls subjected to constant flux heating from below

Two-dimensional steady natural convective flow in a square inclined enclosure with vertical vee-corrugated sidewalls and horizontal top and bottom surfaces has been numerically studied. A discrete heat flux strip of 24% of the total length is flush-mounted on the bottom wall, while the other non-heated parts of the bottom wall and the top wall are considered adiabatic. The two vee-corrugated sidewalls are maintained at constant cold temperature. Grashof number is varied from 103 to 106, corrugation frequency is varied from 0.5 to 2.0, corrugation amplitude has been fixed at 10% of the enclosure height and the enclosure inclination angle is varied to 0◦, 10◦, 20◦ and 30◦ respectively. The enclosure is filled with air (Pr = 0.71). The flow has been assumed to be steady and laminar. Fluid properties have been assumed constant except for the density change with temperature that gives rise to the buoyancy forces. The solution has been obtained using the governing equations written in terms of dimensionless variables. The dimensionless governing equations are solved using finite volume method. Results are presented in the form of streamline and isotherm plots. The results of the present work show that the natural convection phenomenon is greatly affected by increasing the enclosure inclination angle. The variation in the average Nusselt number at the bottom wall, where the heat source exists and the maximum dimensionless temperature are also presented. The results are compared and found to be in a good agreement with other published results

Strategic Agility and its Impact on Organizational Supply Chain Success: Applied Research in a Sample of the Faculties of the University of Babylon

The current research aims to answer the following questions: Is there a relationship between strategic agility and organizational supply chain success? Is there an impact of strategic agility on organizational supply chain success? Through the theoretical philosophy and the intellectual implications of these variables and through the practical application of the research sample, which represented the faculties of the University of Babylon, (15) faculty, the questionnaire was distributed to the actors in these colleges and the deans of the faculties and assistants deans and heads of departments, The research came out with the most important conclusions were the existence of a relationship of significant significance and the existence of a significant effect of the strategic agility in organizational supply chain success

Numerical Simulation of Buoyancy- Driven Laminar Flow Through An Air –Filled Isosceles Triangular Enclosure With A Differentially Heated Side Walls And An Adiabatic Bottom Wall

Thermal And Flow Fields Due To Laminar Free Convection In An IsoscelesTriangular Enclosure Having Thick Conducting Sidewalls Have Been InvestigatedComputationally. Inclined Left And Right Side Walls Are Maintained AtIsothermal Hot And Cold Temperatures Respectively While The Bottom Wall IsConsidered Adiabatic. Problem Has Been Analyzed And The Non-DimensionalGoverning Equations Are Solved Using Finite Volume Approach And EmployingMore Nodes At The Fluid–Solid Interface. Triangular Enclosure Is Assumed ToBe Filled With An Air With A Prandtl Number Of 0.7. Rayleigh Number VariesFrom 103 To 106 Where The Flow And Thermal Fields Are Computed For VariousRayleigh Numbers. Consequently, It Was Observed That The Stream FunctionAnd Temperature Contours Strongly Change With High Rayleigh Number. TheStreamline And Isotherm Plots And The Variations Of The Average NusseltNumber At The Hot Left And The Cold Right Side Walls Are Also Presented. TheResults Explained A Good Agreement With Another Published Results

Studying the effects of a longitudinal magnetic field and discrete isoflux heat source size on natural convection inside a tilted sinusoidal corrugated enclosure

AbstractIn the present work, the effects of the longitudinal magnetic field and the heat source size on natural convection heat transfer through a tilted sinusoidal corrugated enclosure for different values of enclosure inclination angles are analyzed and solved numerically by using the finite volume technique based on body fitted control volumes with a collected variable arrangement. A constant heat flux source is discretely embedded at the central part of the bottom wall whereas the remaining parts of the bottom wall and the upper wall are assumed adiabatic, and two vertical sinusoidal corrugated walls are maintained at a constant low temperature. The range of the variable parameters considered in the present analysis is as follows: the enclosure inclination angle is varied from 0° to 135°, the ratio of the size of the heating element to enclosure width varied from 20 to 80% of enclosure reference length, Hartmann number is varied from 0 to 100, and Rayleigh number varied from 103 to 106. Liquid gallium with constant Prandtl number (0.02) is used as a working fluid with constant properties except the density. The obtained results indicated that streamlines are affected strongly by the magnetic field especially for small values of inclination angle (Φ=0°) and Rayleigh number (Ra=103–106). The magnetic field effect decreases with an increase in the enclosure inclination angle (Φ>0°) especially for large values of Rayleigh number. The increase in Hartmann number will cause the temperature lines to become symmetrical in shape for large values of Rayleigh number (Ra=105–106). The results also explain that the temperature lines are very little affected by the inclination angle especially for small values of (ε=0.4) and (Ra=104), but this effect will increase especially for (ε=0.8) and (Ra=106). The Nusselt number increases first with an increase in inclination angle (0°≤Φ≤45°), then is slightly affected for (45°<Φ≤90°), and finally decreases for (90°<Φ≤135°). An empirical correlation is developed by using Nusselt number versus Hartmann and Rayleigh numbers, and enclosure inclination angle. The increase in Hartmann number and the ratio of heating element to enclosure width will decrease the Nusselt number. Furthermore, four mathematical correlations are extracted from the results and presented, which can be used to accurately predict the average Nusselt number in terms of enclosure inclination angle, Hartmann, and Rayleigh numbers

Power Generation from Utilizing Thermal Energy of Hazardous Waste Incinerators

A large amount of thermal energy is generated from burning hazardous chemical wastes, and the temperature of the flue gases in hazardous waste incinerators reaches up to (1200 °C). The flue gases are cooled to (40°C) and are treated before emission. This thermal energy can be utilized to produce electrical power by designing a system suitable for dangerous flue gases in the future depending on the results of much research about using a proto-type small steam power plant that uses safe fuel to study and develop the electricity generation process with water tube boiler which is manufactured experimentally with theoretical development for some of its parts which are inefficient in experimental work. The studied system generates theoretically (120 kg steam /h at 8 bars) with dry wood as fuel and preheating for the air of combustion and feed water and a diesel engine of (8 hp) four-stroke with single piston converted to steam engine coupled with the electrical generator of (3 kVA). The results are compared with practical values valid in the literature about small power plants of steam capacity (0.1-1) ton/h and operating pressure up to 10 bars. Experimentally, the generated electrical power is little and sufficient to operate a small fan and lump. The current converted steam engine is better than a conventional steam engine in auto lubrication with some operational problems. The boiler efficiency is 63.28%

Challenges And Solutions In Radiation Protection For X-Ray Procedures

Chapter 1 introduces the basic concepts and quantities used in radiation protection. Depending on the type of imaging procedure, the radiation dose given to the patient has the potential to cause harmful biological effects. Understanding these effects requires knowledge of radiation physics, the interaction of X-rays with human tissue, and the biological changes at the cellular and molecular levels. This chapter provides radiologists and other clinicians with the information needed to make informed decisions about how much radiation is acceptable for a given imaging task and the potential benefit to the patient. This information is also important for researchers developing and testing new imaging methods who must weigh the benefits of improved diagnostics or therapy with any potential risks to the patient. An understanding of radiation physics and biology is also essential for epidemiologic studies aiming to assess health risks from medical radiation at the population level. Radiation exposure from X-ray procedures has been identified as a public health problem. Increased utilization of X-ray examinations and the high radiation doses associated with computed tomography (CT) scans have raised concerns about the long-term effects of ionizing radiation on the population. In response to these concerns, the U.S. National Institutes of Health formed the Biomedical Imaging Program in 2004 to investigate and develop novel imaging methods that reduce the radiation dose to patients. This dissertation supports the objectives of the NIH program and presents original research addressing radiation protection for X-ray and CT procedures. The specific aims of this work are: (1) to investigate the radiation dose and potential biological effects from current and novel X-ray imaging procedures; (2) to develop and validate methods for estimating, monitoring, and reducing patient radiation dose; and (3) to investigate the effectiveness and implications of reducing radiation dose in terms of image quality and patient outcomes. These aims are addressed using specific research projects involving exposure assessment and epidemiology, physics and engineering, clinical image interpretation, and image-guided intervention