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Utilization of standardized local and waste resources is of great importance to the economic development in the world. Besides, application of waste material results in more eco-friendly concrete at the same time. In this study, the effects of two different new fillers, named as sea sand powder (SS), as a local available material and olive waste bottom ash, (OW) as a waste material of different proportions incorporated with two different quantities of superplasticizer (SP), on physical and mechanical properties of SCC were aimed to be investigated and compared to those of limestone powder (LS) as a common filler. For these aimes rheology of fresh concrete, compressive and tensile strengths, initial defects, fracture energy and volume changes during hydration were measured. Results showed that there is no considerable difference in hardened properties of SCC by using SS instead of LS; however, differences in volumetric shrinkage and rheological properties, especially for bleeding and segregation, were more pronounced. On the other hand, OW mixes show different outcomes. OW gives more viscosity to SCC mixes and eliminates segregation and bleeding of the mixes containing this filler. Nevertheless, reduced compressive strength and fracture energy and increased volumetric shrinkage and porosity in these mixes were noticeable compared to LS mixes; however, when 5% OW was used, the results found to be more tolerable. Keywords: Self-consolidated concrete, Olive waste ash, Sea sand powder, Limestone powder, Compressive strengths, Fracture energy
Super resolution (SR) is one of the techniques to enhance image resolution in terms of the number of pixels and noise reduction. In SR techniques, a sequence of low resolution (LR) images captured by moderate camera is used to generate a high resolution (HR) image. In this thesis a new Iterative Back Projection (IBP) based SR technique is proposed. In the proposed techniques, IBP technique is improved by using interpolation. This SR technique is achieved by adding an up-sampling and down sampling in each iteration. First of all, four observed LR images are generated by an observation LR model. One of these LR images is considered as a reference image, then interpolation techniques are used to increase the size of the reference image to the size of the ground truth image. This image is considered as an initial guess image. Then the size of initial image is increased and decreased respectively by using interpolation techniques. The interpolated image is decimated to four LR images. The LR images are registered to generate an HR image, then the HR image is sent back to the first step. This process is repeated iteratively until an error criterion is met. The proposed technique is called Iterative Interpolation and Back Projection (IIBP), since an interpolation (up-sampling followed by down-sampling) module is embedded in each iteration. The embedded interpolation module speeds up the convergence of the standard IBP and generates faster results than the standard IBP. The proposed techniques are tested on various well-known benchmark images. The quantitative Peak Signal-to-Noise Ratio (PSNR) results as well as the visual results show the superiority of the proposed techniques over the standard IBP whenever limited numbers of iterations are allowed. As the number of iterations approach to infinity, generally standard IBP gives better results. Keywords: Super Resolution, Iterative Back Projection, Image Registration
The fuzzy classifier is an algorithm that assigns a class label to an object, based on the object description. It is also said that the classifier predicts the class label. The object description comes in the form of a vector containing values of the features (attributes) deemed to be relevant for the classification task. Typically, the classifier learns to predict class labels using a training algorithm and a training data set. When a training data set is not available, a classifier can be designed from prior knowledge and expertise. Once trained, the classifier is ready for operation on unseen objects.In this thesis, type-1fuzzy classifier, and the type-2 fuzzy classifier are used for the machine learning datasets classification. The Wisconsin breast cancer dataset, Iris Dataset, and Tic-Tac-Toe datasets are classified. Type-2 fuzzy classifiers are able to perform better than type-1 fuzzy classifiers which have additional design parameters. Therefore, type-2 fuzzy classifiers are more attractive than the type-1 classifiers. The essential benefits the type-2 fuzzy logic classifiers are their ability to handle more vagueness. Keywords: Classifier, Type-1fuzzy classifier, Type-2 fuzzy classifier, Machine learning dataset and Uncertainty.
In this thesis, the effects of High Density Polyethylene (HDPE) aggregates are studied on fresh and hardened properties of self-compacted concrete (SCC). Therefore, 5 different replacement levels of HDPE with coarse aggregate namely 0 %, 5 %, 10 %, 20 %, and 30 % by volume. In addition, superplasticizer (Glenium 27) and silica fume were added to SCC mixtures by 1.7 % and 10 % by weight of binder, respectively. Slump flow, L-box, and V-funnel tests were performed on the 5 different mixtures to study the workability of SCC. Compressive strength, splitting tensile strength, flexural strength and toughness tests were utilized to study the mechanical properties of the SCC mixtures, while plastic degradation at 100 and 200 °C temperatures, ultra-sonic pulse velocity, and surface cracks observations to determine the durability of the SCC mixtures. After these tests are performed, the results reveal that it is possible to produce self-compacted concrete using HDPE up to 30% replacement level. However, incorporation of HDPE in self-compacted concrete has negative effects on the properties of SCC, decrement in workability, compressive strength, splitting tensile strength, flexural strength, UPV, and it causes surface cracks. On the hand, adding HDPE in SCC has positive effects as well, since it increases the ductility of SCC, and reduces the self-weight of concrete which is promising to produce light-weight concrete. Keywords: high density polyethylene (HDPE), self-compacting concrete (SCC), silica fume, workability, mechanical properties, compressive strength, splitting tensile strength, ultrasonic pulse velocity (UPV), flexural strength, toughness.
Two matching techniques namely linearly tapered and multistep transition were used to design two dimensional radiators between parallel plate regions and 50 microstrip feed line. Transitions for different aperture widths were designed at 2.45GHz, by using a full wave simulation software. As these radiators are not point radiators, they may cause phase errors. In this study, a simple method is suggested to estimate the phase center of the radiating apertures and reduce the phase errors. The suggested method is based on the phase equally in the broadside direction and at another constant angle. The study has been carried out by using a full wave simulation software. The results show that there is almost no phase error over the range of angles of interest for the estimated phase center at the design frequency. The position of the phase does not vary with the distance from the radiator, which means that there are no phase errors as the distance from the radiator varies. Although there is some phase errors as the frequency is decreased or increased, these errors are not significant over a wide band of frequencies. For the multistep transition it is observed that the position of the phase center is closer to the center of the radiator aperture, for the wide apertures. Keyword: Phase center, parallel plate, two dimensional radiation, far field region
Antakya city is in danger as a result of solid seismic actions happening in the territory, and diverse soil conditions that can create a variety of the ground motion amplification. In recent years, scientists and engineers have started to assess the existing structures and their behaviors in resistance to lateral loading, potential earthquake hazard, and vulnerability. Existing structures can be retrofitted to incorporate new improvements and techniques to oppose quake and seismic burdens, which was the most efficient approach to shield against the financial and social disaster influenced by serious seismic action in urban areas. This thesis presents a study on a five-storey reinforced concrete structure was built in 1988 and located in Antakya, Turkey. This work consists of three phases. The first stage, data collection which includes building plans, material properties, structural condition, and reinforcement details. Material properties are measured using non-destructive testing method called model calibration. The model calibration is obtained from building dominant periods and mode shapes of the existing building, which have been measured using forced vibration tests. In the second stage, the analytical modeling of the structure is made using SAP2000. After model calibration, the nonlinear static pushover analysis for the seismic performance evaluation based on the ATC-40 methods has been obtained. Finally, the existing building, which showed low performance according to code requirements, is strengthened by using two different types of external steel brace frames. They have been attached to Y-direction, which has poor performance for both sides until the second floor, and recommended that this strengthening technique is an appropriate method according to the performance and cost analysis. Keywords: Evaluation earthquake, Pushover analysis, Retrofitting, Forced vibration
Previously, various studies were performed to identify safety and environmentally friendly methods for disposing of plastics. Recently, various forms of plastics have been incorporated in concrete to prevent direct contact of plastics with the environment because concrete has a longer service life. In this thesis, the effects of coarse aggregate replacement of Polypropylene as a waste material on fresh and hardened properties of normal strength concrete (NSC) and high strength concrete (HSC) was investigated. To do so, different percentages of polypropylene were replaced by various volumes (0%, 10%, 20%, 30%, 40% and 50 %) of normal and high strength concretes, with the water to cement ratio of 0.58, 0.34 for normal and high strength concrete, respectively. In addition, Superplasticizer (Glenium 27) was added to the NSC and HSC mixed by 0.3% and 2% cement weight, respectively. Slump and VeBe time tests were done to analyse the physical properties of fresh concrete. Moreover, the influences of PP replacement in the hardened concrete were executed by performing splitting tensile strength (fs), compressive strength (fc) and flexural strength (ff) tests. Rapid chloride permeability (RCP), heat degradation at 200 °C, water absorption, and non-destructive tests such as Ultrasonic Pulse Velocity (Pundit) and Schmidt hammer (rebound) were also conducted. The results showed changes in mechanical properties of normal strength concrete and high strength concrete as the percentages of PP increases. The amount of fs, fc, and ff of normal and high strength concrete decreased with the increase in the amount of polypropylene at 28 days. Furthermore, high water absorption was observed with the increasing of PP. According to the results of the Pundit test the replacement of Polypropylene increased the quality of concrete up to 50% in comparison with the control samples. It is worth noting that negative effects in fc, fs, ultrasonic pulse velocity, and crack development were observed after 200 °C heat exposure. Keywords: Polypropylene (PP), Normal strength concrete, High strength concrete, workability, Mechanical properties, Non-destructive test, Water absorption, Permeability, Heat exposure
A mobile ad hoc network (MANET) is one of the narrowest and most specific of research topics in the field of telecommunications. The growth of this type of network, and the large number of applications with mobility requirements, has led to a wider study and research in the analysis and enhancement of the work in this area. In such networks, nodes are communicating with each other without the need of a centralized administration (This type of network does not contain any type of server or base station). In this topology, the communication between the nodes is done by pair to pair within the coverage area. The routing is managed and organized by a number of routing protocols. A limited coverage area, collision and power consumption for mobile nodes are the main problems occurring in such networks. In this thesis, two important MANET routing protocols were used, AODV and DSR to analyze their behavior with two different voice encoding schemes, Pulse Code Modulation (PCM) and Global System Mobile (GSM). The PCM and the GSM encoding voice schemes are evaluated with a different number of clients using a Random Way Point Mobility (RWPM) model. OPNET simulator version 17.1 was used to build the modeler and to simulate the ad hoc mobile network model. The benefit of this simulation program is the ability to build models for different network topologies and the large number of available choices for node performance statistics. In addition to that, results are more confident and accurate compared to other simulation programs found in the literature. From the analysis of the simulations, it was concluded that, in all cases, the AODV protocol performed better than the DSR protocol. This is because AODV doesn’t save the entire possible path from source to the destination node. It takes the newest and most refreshable one. On the other hand, DSR caches all possible paths to the destination. It is also shown that PCM performance is better and more quality than GSM in most of the performance metrics except end -to- end delay, for both AODV and DSR routing protocols. Keywords: OPNET simulator, Mobile Wireless Ad Hoc Network, AODV, DSR, PCM, GSM.
Passive vibration attenuation of modern mechanical structures is one of the most essential technologies applied to the arsenal of modern mechanical structures. In this thesis, dynamics analysis is performed on viscoelastic (VE) beam and plate sandwich structures. The proposed structures are composed of a VE core and aluminum face sheets as the substrate layers on both sides of the structure. The small-strain VE material is modeled based on the complex constant moduli model. In the modal analysis, the model effective mass analysis is performed to investigate its dominant mode shape and its sweet spot at resonance. Then, in the harmonic analysis, the resonance frequency is obtained to evaluate the performance of the VE sandwich structures via the maximum deformation. A comparison between the results of an analysis of viscoelastic sandwiched structures with subsequent done using FE models. A numerical application is accomplished to develop the integral shear finite element and modal assembly of the stiffness element and mass element established according to strain energy and the Hamilton principle. The harmonic analysis is done using ABAQUS® software with both C3D20RH®, CPS8R where C3D20RH indicates a 3- D element with 20 nodes with reduced integration technique and hybrid formulation and CPS8R indicates 2-D plane strain with eight nodes with reduced integration technique, the results are compared against analytical solutions form the literature, a parametric study is done on the beam’s core thickness to study the effect on the damping characteristics of the beam, the results showed that the modal developed in MATLAB® achieved the least error compared to the analytical solution from the literature and then comes the Abaqus® software solution, also the parametric study showed that the natural frequency of the beam does not change with the increase of the core thickness, however, the loss factor is directly proportional to the thickness of the viscoelastic layer of the beam. Keywords: Viscoelastic, Sandwich Beam/Plate, Dynamics Analysis, Complex Constant Moduli, Finite Element Method, Shear Deformation Theory
Data Envelopment Analysis (DEA) is a methodology to compare efficiency of Decision Making Units (DMUs). DEA is an extension of Charnes, Cooper and Rhodes work by introducing CCR model in 1978. Ranking DMUs is one of the main purposes of DEA in management and engineering. DEA evaluates some DMUs with efficiency score one as efficient DMUs and we therefore need to produce a reliable method for fully ranking DMUs. Some methods have been proposed in this concept and newly Khodabakhshi and Aryavash (2012) ranked DMUs relative to their combined maximum and minimum efficiency scores where efficiency is defined as ratio of weighted sum of outputs to weighted sum of inputs. Due to some obtained weights (multipliers) in DEA may be zero, previous methods have low ability in ranking DMUs because of eliminating the effect of corresponding input and outputs on DEA evaluations. We expand their method by assigning lower bounds on multipliers using facet analysis and then we propose an equitable and precise method for ranking all DMUs based on the modified CCR. Keywords: Data envelopment analysis, decision making unit, rank.