The buildup of ice on lifting devices during flight manifests a risk to any aircraft safety. A major rolling parameter in the criteria of aircraft icing is the ice roughness which indicates surface roughness induced with the initial stages of in-flight ice accumulations. Icing type classification was related to the structure and appearance of the ice may vary based on the atmospheric and flight conditions in which it forms. Present work utilizes rime layer since icing type frequency of occurrence would reach a percentage of (71.7%) for this layer. Present work will focus on studying the effect of ice accretion layers on drag and lift coefficients in addition to some of aerodynamics coefficients with respect to different angles of attack range between (-20o to 20o) for different flight speed velocities having a range of (15, 31, 40, 47, & 54 m/s) through using of (F-16) aircraft prototype that has a 1:48th scale where the accretion layer was simulated on both wing and tail area. Wind tunnel data was corrected for the reason related to the streamlines that was guided in straight manner by the side walls of the wind tunnel but also they are curved at specific distances from the full scale airplane, in comparison to the wind tunnel wall correction. Correction related to the wing shape and its sweep in addition to its span in accordance to the width of the test section therefore it is essential to conduct some corrections for the angle of attack and the drag coefficient. It was concluded that the trend of drag coefficient tend to be increased for both positive and negative magnitudes of the angle of attack where the lowest value of the drag coefficient occurs at an angle of attack equal to (0o) with a value of (0.05) while the maximum value for the drag coefficient almost equal to (0.48) while for the case of ice accretion a higher values for drag coefficients appeared at higher values for the angles of attack but with a new behavior represented by the range of drag coefficient that entirely increased with a maximum value of (0.38). It was found that the most efficient angle of attack in the ordinary case of study with no ice accretion appeared to have a value of (5o) while when ice accretion was adopted, the lift/drag ratio start to decrease with the increase of the angle of attack confirming the foreseen behavior of lift force reduction related to aggressive increase in drag forces exerted on the aircraft results from ice simulated layer.

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Breakwater is a structure made parallel to the shore line and placed at certain distance from the coastline. The structure has function to protect the coast from the attack waves. The division of the energy waves reflected, destroyed, and passed on depends on the characteristics of the wave coming, shapes and dimensions of the breakwater. To find out the value of the transmission coefficient (KT), reflection coefficient (KR), and dissipation coefficient (KD) that occurs in breakwater type cube, and the influence wide the top breakwater (B) then carried out experiments at Hydraulic Laboratory, Faculty of Engineering, Tadulako University. Scale models used were 1: 30 with five variations wide the top breakwater and five frequency variation with two conditions of surface water. The results showed that the model of the breakwater that obtain the value of transmission coefficient (KT) and reflection coefficient (KR) smallest, largest dissipation coefficient (KD) is a model five submerged condition with the interval value of KT 0,333-0,366, interval value of KR 0,111-0,213, interval value of KD 0, 443-0, 556, merged condition with the interval value of KT 0,083-0,220, interval value of KR 0,171-0,333, interval value of KD 0, 500-0, 671 with a wide of the top breakwater 10 cm. The parameters that affect the transmission, reflection, and wave dissipation in breakwater were wide the top breakwater (B), high waves coming (Hi), wave length (L), and the depth of the water.

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Like an earthquake, sinkhole subsidence can strike with little or no warning and can result in damage to infrastructure and loss of human life without admonition. Sinkhole subsidence is sudden and abrupt fall of the surface into the void created due to mining activity. It cannot stop, but can be controlled in different ways where complete strata deformation may be dangerous or costly effects. In recent years at South Eastern Coalfields Limited (SECL) several sinkholes have been reported and to study the various influencing parameters which triggering the sinkhole, this study has taken up. The parameters which are causing to sinkhole have been collected & compiled based on parametric analysis to this parameters model was developed in Artifical Neural Network (ANN) by using EasyNN-plus software for sinkhole depth prediction. The same developed model has been validated by randomly selected four different mines with model results matching to ± 10 % of error.

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This theoretical model mathematically analyses the steady flow of blood in a tapered narrow artery with mild stenos is and dilation, treating the blood as non-Newtonian Casson fluid model. The resulting nonlinear boundary value problem is solved to obtain the analytic expressions to the velocity profile, volumetric flow rate, pressure gradient, wall shear stress and longitudinal impedance to flow. The influence of various flow parameters on the aforesaid rheological quantities are analyzed through appropriate graphical and tabular representation of data. It is noted that the pressure gradient and wall shear stress increases with the increase of the maximum depth of stenos is, yield stress and consistency index of blood and, it decreases with the increase of the angle of tapering, flow rate and maximum height of dilatation. It is also found that the blood velocity decreases considerably with the increase of the yield stress of blood and it decreases significantly with the increase of the consistency index. The percentage of increase in the frictional resistance to flow increases rapidly with the increase of the maximum depth of stenos is and maximum height of dilatation and, it increases marginally with the increase of the yield stress of blood.

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A bibliometric study was developed based publications of investigation in electric vehicle from 2007 to 2016 available in the science citation Index-expanded database from Web of science, the information was identified in the version on line of SCI-Expanded, Web Thomson Reuters of Science, supported in addition on a powerful tools of information processing like Hitscite. The extracted files were analyzed to determine the number of citations, including publications by year, language, country or region, Journals, articles and authors in order to determine the evolution of this field of study.

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Cold-formed steel (CFS) sections are lightweight material that are made by rolling or pressing thin gauges of sheet steel into goods in a room temperature environment that are usually manufactured into channel sections, Z-sections, hat sections and some other open sections. CFS usage has increased in the recent years as a structural frame not only for residential buildings but also for multi-storey commercial buildings. Therefore, the understanding of the behavior of CFS sections especially in its connection are important to be studied. This paper describes the behavior of CFS sections by reviewing the previous studies specifically on bolted connection of cold-formed steel sections, emphasizing on the design guidelines from Euro code 3: BS EN 1993-1-3 and Euro code 3: BS EN 1993-1-8. The findings from previous studies are discussed in this paper.

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This study investigates the influence of incorporating bioactive ceramic particles on the mechanical performance of acrylic bone cement. The formulated composites contain certain weight fractions of hydroxyapatite (3,8,16) wt%, magnesia (2,3.5,5) wt% and a fixed amount of titania (2 wt% ). Vacuum mixing technique was adopted in order to reduce porosity and stress concentration. The microstructure of fabricated composites was characterized through Scanning Electron Microscopy (SEM) and the mechanical properties were evaluated through tensile and michrohardness tests. Results showed deterioration in tensile strength with increasing amount of fillers which is attributable to the agglomeration of reinforcement phase which represented weak points in the matrix for crack initiation and propagation. Moreover, the strength results are consistent with the SEM images that showed significantly increased agglomerates with increasing amount of fillers. Results showed an enhancement in modulus of elasticity with the incorporation of strong fillers. However, the results of microhardness test did not reveal significant changes, where hardness can be affected by content of residual monomer, porosity and other material properties in addition to composition.

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The further development of civilization is decelerated by lack of energy resources. This is especially significant for the construction industry. Considerable energy savings can be achieved by using specially prepared raw materials. Examples of these raw materials are volcanic rocks of the Republic of Buryatia. The modern complex approach to solving problems also requires additional development of resource-saving technologies, which imply the widespread use of associated industrial products, designed to significantly reduce the energy intensity of cement and concrete production without a fundamental change in technology. The paper deals with the use of natural pearlite and fly ash of Gusinoozersk thermal power plant (TPP) to obtain composite binders. It was investigated that natural pearlite and fly ash can be used as part of a multi-component fine cement and low water requirement binder (LWB). Compositions of binders were obtained with super plasticizers based on sulphonated naphthalene-formaldehyde polycondensates - C-3 and based on polycarboxylates - Sika Viscocrete. It is shown that the mechanism of action of these additives on the properties of the composite binders appears in the range up to 15 nm.

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Cross Site Scripting (XSS) attacks are most popular web application attacks. In XSS attacks, the attacker injects malicious code into a web application and execution of that malicious code at the browser side may steal session tokens, web cookies, or other sensitive information of the user. In this paper, we analyzed a large collection of XSS attacks to find XSS attack patterns. Based on this analysis, we are able to find XSS attacks effects on different programming languages, domain extensions, and common web pages. Furthermore able to find script tags frequency, keywords frequency, and special characters frequency in XSS attacks. We also reviewed different prevention techniques of XSS attacks.

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Contaminants flow through compacted soil liners and covers are usually considered under saturated conditions during design stage. Whereas, the compacted soil barriers in reality are neither completely saturated nor completely dry, rather they are in an unsaturated state. Thus, unsaturated flow principles need to be properly simulated to determine the contaminant flow through compacted soil barriers in order to protect groundwater. Soil water characteristic curve (SWCC) which is the relationship between soil suction and water content is the main modeling parameter of unsaturated soil. This paper evaluates the SWCC data of a tropical laterite soil used as a liner material in sanitary landfill. The effect of gradation with respect to fines content on the dry of optimum, optimum and wet of optimum moisture contents on SWCC were investigated. Laboratory tests using pressure plate apparatus were conducted to determine the variation of volumetric water content with soil suction for a pressure range of 1 kPa to 1000 kPa. The experimental SWCC data were fit to the Brooks and Corey parametric equation to compute the unsaturated hydraulic conductivity. Based on the SWCC data, greater air entry suctions were obtained for specimens with higher fines contents when compacted wet of optimum moisture content and the water retention capacity increased with increase in fines content. Using the SWCC, the unsaturated hydraulic conductivities of the soil liner used in simulating leachate migration were computed.

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This paper offers applicable method to control the AC three-phase induction motor squirrel-cage by using the microprocessor TMS320F (manufactured by Texas Instrument, USA). This new version of Digital Signal Processing (DSP) controllers permits project of smart controllers for AC and DC electric motors which can yield improved task, a smaller amount system device, lesser system price and bigger effectiveness. Most of the controls methods on the inverter-fed AC induction motor derive with different schemes are classified into two main methods: scalar and vector methods. The V/f method is considered as scalar method while the Direct Torque Control (DTC) and Field Oriented Control (FOC) methods are presented under the vector methods. The different mentioned methods are also developed to subdivide into more specified methods such as direct and indirect FOC, speed sensor and speed sensor less FOC. In addition, DTC contains two techniques: Direct Self–Control (DSC) and Space Vector Modulation (SVC). All these methods share in their work mainly by using the software algorithm full speed verification of F28335 code which is created by using directly microprocessor such as TMS320F indirect by microcontroller (micro-computer as example). This present study introduces the design and implementation of high performance microprocessor TMS320F controller for operating three-phase induction motor via DC to AC inverter-fed. The inverter used is consisted of three arms- two levels of IGBs type G4PC50UD. The Pulse Modulation Unit is fabricated in the laboratory using eight ICs type SN74LS14N, 14 pins and six ICs type A3120, eight pins. The tests have been conducted in University of Diyala, College of Engineering, AC machine Laboratory which complemented with the expected results.

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Abstract:

The main objective of this paper is to show the design of an electromechanical lock controlled by a Bluetooth communications module, the description of the two main structural blocks is made, which are: Mechanical structure based on an endless screw and the electronic control unit based on an embedded 32-bit microcontroller system. The proposed design also establishes the use of a Bluetooth Low Energy (BLE) communication module associated with the operation of an application for smart phones that allows activating or deactivating the electromechanical mechanism designed. Likewise, emphasis is placed on the description of the communication frame used, describing its operational structure byte by byte.

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Steganography is the hidden communication, concealing the existence of secret information. Steganography hides the secret messages with high security by obscurity. This technique is mainly used in image processing to maintain its confidentiality, provides authentication and improves the medical image security. This paper provides a state-of-the-art review of the steganographic techniques such as Spatial and Transform domain embedding schemes, the different algorithm utilized to implement the embedding and extracting process in steganographic system. Implementation of steganography yields high Imperceptibility, Robustness, embedding capacity, security with PSNR.

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Underwater acoustic sensor networks (UASN) have fascinated in recent years and grown rapidly with the longing to monitor the enormous portion of the world, wrapped up by the oceans. The acoustic wave has been used as a physical layer technology for monitoring the long-range applications in underwater with a few drawbacks. These networks deal with variable propagation delay, energy constraints and limited bandwidth that is strenuous for designing a substantial Medium Access Control (MAC) protocol for underwater sensor networks. In this paper, we have illustrated the applications of UASN and deliberately pointed out the advantages of using sensor technologies in deep oceans. On another fold, we have developed a hybrid based MAC protocol for time-critical applications. The proposed MAC is a cluster based protocol which helps to increase the lifetime of sensor nodes. To reinforce the channel efficiency, the multilevel scheduling in data phase is initiated with two queues depending on the priorities fixed by the cluster head. With this promising scheduling, we could eliminate the waiting time of the sensor nodes and achieves the higher throughput. The simulation results indicate that hybrid based MAC protocol increases network throughput, and reduces the end to end delay.

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The article represents methods of evaluation of stress distributions in casing supports of wells and elements of foundation caused by local loads and compacting in soil base. Conditions of load’s origin were identified. Main methods and equations are given and proved by conducted experiments. Model of stress-strain state in casing support as an applicable result is created and shown. Impact of compression on absolute value of durability is presented.

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The main applications of computers today is working with large massive of data, where are all sorts of searches and sort the most labor-intensive operations. Existing computer systems used address memory architecture. In such an arrangement, to effect retrieval of data in the memory, it is necessary to make the reading of each memory module address and compare it with the search argument, resulting in finding the desired information in the memory takes a lot of computer time. This fact negatively affects the speed of a computer system as a whole. The paper considers the possibility of implementing a coprocessor module association on modern element base for specialized computer systems. The aim of this work is the development and research of associative co-processor module on PLDs, for specialized computing, for example, multi-processor, systems, performing associative function and data storage functions. The object of the development and research of this article is an associative co-processor based on PLD. In order to achieve the objectives used CAD Web pack ISE from Xilinx with the ability to create and simulate the operation of a device using the schematic editor, and in using VHDL language, which greatly facilitates the synthesis of projects for use on modern components - PLDs. Developed and debugged VHDL-code co-processor module association and its individual units. Functional and performance testing of devices tested in the CAD, obtained by the timing charts. The results of the study are obtained VHDL-code module of the associative co-processor, which is synthesized from broaching the file to configure the PLD.

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CRDID (Common Rail Direct Injection Diesel), automotive derived engine, main advantage is the enormous amount of experimental data. These engines are produced in millions of units and reliability data based trillions of hours are available. It is also possible to run automotive CRDIDs with jet fuel. It is also possible to mix the two fuels with a proper ECU (Electronic Central Unit) mapping. Therefore, the necessity to refuel in airports can be eliminated. Moreover, the additional mass of CRDIDs is largely compensated by the reduced fuel amount necessary to exploit the same mission/flight. However, an additional cooling system duct should be added. For this purpose, fans are replaced by ejector exhaust (augmenter) that does not need fan additional power. Solid Works Flow Simulation confirmed the feasibility of an ejector-exhaust-powered cooling. However, pressure fields around the helicopter varies in a very significant way in the different flight conditions. High cooling duct efficiency requires pressure and clean air at the intake port and negative pressure at the duct nozzle. Therefore, a optimization of the cooling duct positioning has been carried out on a common light helicopter (Eurocopter EC 120). Several different solutions have been simulated with Solid Works Flow Simulation. CFD confirms the ejector choice and the design criteria. The best configuration is a derivation of a Formula 1 intake duct. This solution proved to be the most effective for the CRDID-exhaust powered cooling duct. The result is that the ejector exhaust (augmenter) is extremely effective. With two small intakes at the side of the mast, the pressure differential between the intake and the nozzle of the duct proved to be extremely stable in every flight condition, even with crosswind.

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Contrast change is a special type of image distortion; it is a very important for visual perception of image quality. Most No-Reference Image Quality Assessment (NR-IQA) metrics are designed for the quality assessment of images distorted by compression, noise and blurring. Few NR-IQA metrics exist for Contrast-Distorted Images (CDI). Existing approaches rely on global statistics to estimate contrast quality. The current No Reference Image Quality Assessment for Contrast-Distorted Images (NR-IQACDI) uses global statistics features. Room for improvement exists, especially for the assessment results using the image database called TID2013 which has poor correlation with Human Visual Perception (HVP); Pearson Correlation Coefficient (PLCC) < 0.7. In this work, instead of relying on the global statistics features, NRIQACDI is presented based on the hypothesis that image distortions may alter the local region statistics (Local patches features). Our experiments are conducted to assess the effect of using local patches features with natural scene statistics (NSS). The experiment results are based on K-fold cross validation with K range from (2 to 10). The statistical tests indicate that the performance using local statistical features are better than that of the NRIQACDI. The use of other statistical features and selection methods should be further investigated to increase the quality of prediction performance.

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CPVA (Cantilever piezoelectric vibration absorber) is a mechanism consisting of masses, springs, dampers and piezoelectric cantilever. In this study; CPVA acts as a vibration absorber and can generate electrical energy. CPVA is able to reduce the vibration of the damped system that vibrates translations and rotations due to the shift in position of excitation force on the main mass. At the first natural frequency the damped system is 7.56 rad/s, the CPVA mechanism reduction value with distance ß =0.4m from the center of main mass, capable of damping the maximum translational vibration by 98% and the maximum rotational vibration of 67%.Furthermore, the number of piezoelectric cantilever as many as 1400 pieces produce electrical energy for 8.6 e-05 W.

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In this paper, we study the Maximum Likelihood Estimation (MLE) and Ordinary Least Squares Estimator (OLSE) methods for estimation of the unknown parameters of the modified Weibull distribution. A comparison between these estimators is provided by using extensive simulation and mean squared error criteria to select the best method. Computational experiments on the presented methods are reported.

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