Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
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Master Thesis Lab-on-a-chip devices for drug screening(Izmir Institute of Technology, 2019) Gökçe, Begüm; Pesen Okvur, Devrim; Çağır, AliBreast cancer is one of the cancers with the highest incidence and mortality rates in women in Turkey as well as in the world. Tumor micro environment comprises of cancer and normal cells, extracellular matrix, soluble biological and chemical factors. Research has shown that cell shape, adhesion, migration, response to growth factors and drugs are different in 2D and 3D culture. Today, only 8 out of 100 anti-cancer clinical trial gives effective results. 3D cell culture systems have shown to be a necessary step between in vitro, in vivo and clinical studies. Therefore, it is necessary to better understand the interactions of cancer cells with their micro environment, for which new cell culture setups are required. The most apparent disadvantage of widely used 3D cell culture setups is the lack of stromal cells. The systems to be developed should both provide a 3D environment and comprise multiple cell types. The drug screen in 3D tri-culture method with a lab-on-a-chip device, that will be developed in this study will be able to answer these needs. Cell lines that represent different breast cancer types alone or together with stromal cells were cultured in 3D in the to be developed lab-on-a-chip; by determining the effects of drugs with different targets on the viability and distribution of cells, a drug screening method is developed.Master Thesis Modeling and Analyses of Pretwisted Beams Having Piezoelectric Smart Materials(Izmir Institute of Technology, 2017) Akari, Merve; Yardımoğlu, BülentIn this study, modeling and analyses of pretwisted beams having piezoelectric smart materials are acomplished by using Finite Element Method. A computer program is developed by using APDL (ANSYS Parametric Design Language) in ANSYS with SOLID45 and SOLID5 for pretwisted beam and piezoelectric layer, respectively. The effects of the pretwist angle on electric field are analyzed.Master Thesis Development of Peg and Peg-Peptide Based Drug Delivery Systems(Izmir Institute of Technology, 2016) Balcı, Beste; Top, AybenIn this study, two types of drug delivery systems (DDS) were prepared; mPEG (methoxy polyethylene glycol)-HYD (hydrazide)-DOX and mPEG-peptide-(HYD)-DOX. In the design of the conjugates, mPEG was used to increase the blood circulation time. HYD provided an acid cleavable bond between the carrier molecule and DOX, whereas peptide containing histidines imparted pH responsiveness of the molecule. Doxorubicin (DOX) was selected as a model anti-cancer drug. DDS were synthesized using two steps; hydrazide functionalization of carboxylic acid of the carrier molecule followed by DOX conjugation. Hydrazide form of the carrier molecules denoted as HYD1 and HYD2 were obtained using adipic acid dihydrazide (AADH) and carbohydrazide (CH), respectively. To increase DOX conjugation, trifluoroacetic acid (TFA) and DOX amounts were changed and the reactions were carried out at the conditions giving the highest DOX conjugation (mPEG-HYD:DOX:TFA= 2.5mg:2mg:20μL per 1 mL of DMSO). The peptide (AT1=CGGGHHHHHHGGGE) was synthesized using solid phase peptide synthesis (SPPS) and PEGylated using mPEG-maleimide to obtain mPEG-AT1 conjugate. The purity of AT1 and mPEG-AT1 were confirmed using mass spectroscopy and high performance liquid chromatography (HPLC). DOX conjugation percentages were obtained as 62 7, 60 3 and 35 + 3 for mPEG-HYD1-DOX, mPEG-HYD2-DOX and mPEG-AT1-HYD1-DOX, respectively. Drug release studies indicated modest pH responsiveness of the carrier molecules obtained using AADH. On the other hand, mPEG-HYD2-DOX released 13% of drug at the end of the 72h independent of pH. For mPEG-AT1-DOX, drug release percentage values were obtained as 15% and 30% at pH 7.4 and 5.0 respectively. Cytotoxicity of the conjugates of DDS was determined using lung cancer (A-549) cell lines. DOX equivalent IC50 values were determined as 20, 40 and 5 for mPEG-HYD1-DOX, mPEG-HYD2-DOX and mPEG-AT1-DOX respectively.Master Thesis Energy and Environmental Performance Based Decision Support Process for Early Design Stage of Residential Buildings(İzmir Institute of Technology, 2016) Gerçek, Mümine; Durmuş Arsan, ZeynepDeficiencies in systematic approaches for design decision support to increase energy and environmental performance of buildings in Turkey are projected as the major problem of this study. Rare usage of computational methods for evaluating and improving building performance, need for informational assistance in design, as well as lack of interaction between systematic knowledge and building practice are the secondary problems. This thesis mainly aims to test usability of the decision support process assisting architects in early design stages of residential buildings. Assessing the uncertainties in building performance caused by design parameters and climate change, in terms of determining the most significant parameters on annual energy consumption for heating, cooling and operational CO2 emissions in hot humid climatic region of Turkey is the significant objective of the study. The relation between input parameters and building performance indicators is examined by the uncertainty and global sensitivity analyses for a residential building in İzmir, Turkey. The process is supported by usability testing held with the architect in practice. The results indicate that, the sensitivity between input and output parameters changes according to the projected weather conditions and different floors of the building. The SHGC of windows on south-west, north-east facades, and window U values are the most effective parameters on energy and environmental performance. The proposed decision support process is approved to be applicable for early design stages of the selected building, and helps creating consciousness about the importance of systematic design decision approach for the building professional.Master Thesis Rheological Characterization and Extrusion of Alumina Based Pastes for the Preparation of Tubular Ceramic Membrane Supports(Izmir Institute of Technology, 2016) Yılmaz, Kenan; Çiftçioğlu, MuhsinMembrane applications in the industry currentlyis dominated by polymeric membranes, however, in recent years the development of ceramic membranes gained significant attention because of their superior chemical/thermal stability and corrosion resistance. The separation capacities of ceramic membranes basically depend on the nature of the selective oxide layers formed on the inner surfaces of tubular ceramic supports. Ceramic tubular membrane supports were prepared from alumina pastes, with solid loadings as high as 55 vol. % and water was used as the major liquid phase. Boehmite along with hydroxypropyl cellulose ethers with different molecular weightswere used as binder materials. Glycerol was used as a lubricant in the paste formulations. Extrusion of alumina paste was conductedwith a ram extruder using capillary dies with a series of L/D ratios at different extrusion velocities and the data was analyzed by using Benbow and Bridgwater model. The rheological properties of various pastes were determined according to the 4 and 6-parameter models.The six parameter model was concluded to better represent the experimental data. The viscosities of the paste batches were also determined by using the model parameters o, 1, and exponent n. The pastes were determined to have a shear thinning behaviour Piston extruder was used for shaping of tubular ceramic supports and the pressure varied in the 20-90 bar range with paste composition and rheology. The tubular extruded supports were dried, debinded to burn out organic binders and sintered at 1525ºC for the formation of about 40% porous mechanically strong membrane supports.Master Thesis Development of protective nano-coatings for electro-optical systems(01. Izmir Institute of Technology, 2016) Karabıyık, Merve; Ebil, ÖzgençElectro-optical (EO) systems have wide range of applications and in recent years, especially the use of EO imaging systems in military and civil aviation applications have substantially increased. In these applications, EO systems are exposed to quite harsh and unstable operating conditions like sudden changes in temperature and humidity, dust, fog, physical shock, vibration and radiation. If their optical surfaces such as prisms, lenses and mirrors are damaged due to these conditions, their repair usually is not possible. To overcome these problems, it is necessary to develop special protective coating layers for optical surfaces. The main goal of this study is to produce protective, self-cleaning and super-hydrophobic polymeric thin films for optical surfaces of the electro-optical (EO) systems. Initiated chemical vapor deposition (iCVD) is a novel method for the fabrication of thin film coatings and it has many advantages such as low production cost, very low deposition temperature, 3D geometry coating performance and high deposition rate. Therefore, iCVD was employed to fabricate homopolymers of poly (glycidyl methacrylate) (PGMA) and poly (1H, 1H, 2H, 2H-Perfluorodecyl acrylate) (PPFDA) and P(GMA-PFDA) copolymer thin-films as protective coatings for EO systems. Optical modeling and simulations were performed to determine the effect of film thickness and refractive index on optical performance of substrates to be coated. Optical performance of fabricated coatings was also measured between 400 and 1000 nm range to confirm that protective coatings do not have any measureable impact on optical performance provided that the protective film thickness is kept between 50 nm to 1 μm. The surface morphology of the protective coatings was evaluated using a variety of analytical tools such as Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and Contact Angle measurements. Optical tests were performed by following MIL-F-48616 Military Standard (MIL-STD). The best protective coatings were obtained by using P(GMA-PFDA) copolymer which yields good mechanical properties due to epoxy pendant group and super hydrophobicity due to incorporation of fluoro monomer.Master Thesis Vibration Analysis of Laminated Composite Circular Plates With Radial Slots(Izmir Institute of Technology, 2014) Baltacı, Çetin Özgür; Yardimoğlu, BülentVibration characteristics of laminated composite annular circular plates with radial slots are studied by Finite Element Method (FEM). As theoretical background, vibration analysis of orthotropic annular circular plates, mechanics of laminated composites and finite element modeling are summarized. Laminated composite annular circular plates with radial slots are introduced. The APDL program in ANSYS is developed for the titled problem and verified by the available literature for the annular circular plate. Then, the effects of lamination parameters on natural frequencies are investigated.Master Thesis Vibration Analysis of a Giromill-Type Vertical Axis Wind Turbine(Izmir Institute of Technology, 2013) Akgüneyli, Melih; Yardımoğlu, BülentVibration characteristics such as natural frequencies and mode shapes of Giromill-type vertical axis wind turbines (VAWTs) with different design parameters are studied by Finite Element Method (FEM). As design parameters, length of the blade, thickness of the blade and the support distance of the blade are considered. On the other hand, local wind characteristics are considered for aerodynamic calculations. The well known commercial software package, ANSYS, is used for finite element analysis. Aerodynamic loads and centrifugal forces are taken into account in calculating the natural frequencies. In order to see the interactions of the parameters of the VAWT, seven models are obtained by modification of model I which is a reference model. Vibration characteristics of all models are found. The obtained results are presented in tabular forms.Master Thesis The Metaphor of "curtain Wall" in the Modern Architectural Discourse(Izmir Institute of Technology, 2013) Kutluay, Pınar; Yücel, Şebnem"Curtain wall" is mostly regarded as a direct outcome of the industrial reform in the Nineteenth Century. Following technological determinist approach, most of the studies about curtain wall seek to find an origin for it in the late Nineteenth Century. Different from these studies, this thesis investigates the formation of the discourse of curtain wall in view of its metaphoric background. Instead of focusing only on technology as the main factor, the study unveils different sides of the discourse which remained in the background and deciphers how "curtain," a term borrowed from textile and theatre, has been associated with facade of frame structure. In detail, the study sheds light on how frame structure, one of the main components of a curtain wall system, came to be called as "skeleton" with reference to the theory of organicism. The dressing --Bekleidung-- theory of Gottfried Semper is also examined as an alternative interpretation of the relationship between structure and facade regarding monumentalization through dressing and masking; as skeleton structure led architects to reconsider wall with concern of representation. Furthermore, the study concentrates on the architectural environment of Chicago in the second half of the Nineteenth Century, exploring two mainly different interpretations of frame structure which both arose from a shared concern of representation by some significant architects, including Louis H. Sullivan, who was also interested in monumentalization through ornament. This thesis claims that curtain wall is a metaphor invented to reconcile the emerging technology with the theory of representation which had diverse sides.Master Thesis Scheduling the Turkish Soccer League Using Mathematical Programming(Izmir Institute of Technology, 2013) Güney, Faruk; Aslan, Burak GalipGenerating a fair and feasible schedule is a difficult challenge for sports league organizers because of having various requirements from various involved parties. Some of these requirements are fairness requirements. Turkish Soccer League should be scheduled by according to these requirements especially because of the reduction of the confidence in Turkish Soccer League organizers and authorities due to the case of match fixing in recent years. As scheduling Turkish Soccer League, the prior requirements in our study are the minimization of the total number of break, carry over effect (COE) value of a schedule in addition to meeting the conflicting venue constraints. We decomposed scheduling process in phases to facilitate our solution. We used a different variation of first-break-then-schedule approach, proposed by Rasmussen and Trick (2008), to meet break conditions initially and solved each phase by applying different mathematical programming techniques including Integer Programming (IP) and Constraint Programming (CP). Our study generates a schedule having carry over effect (COE) value which is one of the lowest ones in European soccer competitions, in addition to minimizing total number of breaks.