Manuscripts have an essential importance as being irreplaceable parts of our cultural heritage. It has long been known that these works have been suffered from serious damages due to the corrosive effects of the inks. In this study, the influence of inks prepared according to historical recipes on the degradation of model paper has been investigated. Totally, sixteen ink solutions were prepared and applied on Whatman No. 41 filter papers. The mostly examined ink is the iron-gall-ink which is known as very corrosive. Changing the ratios of the ingredients in the ink, it is aimed to understand the degradation mechanism of the cellulose caused by the iron-gall-ink. Influence of iron to gallic acid ratio, copper to iron ratio and the effect of saffron on ink corrosion were examined. Also the influence of colored inks (red and green) / prepared according to the historical recipes on cellulose degradation was studied. In order to determine the changes in the cellulose in time, dry heat accelerated ageing was performed on the paper samples. UV-Vis spectroscopy, FTIR-ATR and Color spectrophotometry were used to investigate the changes in the chemical composition of the cellulose after accelerated ageing.

In this study, effect of surface roughness on convective heat transfer and fluid flow in two dimensional parallel plate microchannels is analyzed by numerically. For this purpose, single-phase, developing, laminar fluid flow at steady state and in the slip flow regime is considered. The continuity, momentum, and energy equations for Newtonian fluids are solved numerically for constant wall temperature boundary condition. Slip velocity and temperature jump at wall boundaries are imposed to observe the rarefaction effect. Effect of axial conduction inside the fluid and viscous dissipation also considered separately. Roughness elements on the surfaces are simulated by triangular geometrical obstructions. Then, the effect of these roughness elements on the velocity field and Nusselt number are compared to the results obtained from the analyses of flows in microchannels with smooth surfaces. It is found that increasing surface roughness reduces the heat transfer at continuum conditions. However in slip flow regime, increase in Nusselt number with increasing roughness height is observed. Moreover, this increase is found to be more obvious at low rarefied flows. It is also found that presence of axial conduction and viscous dissipation has increasing effect on heat transfer in smooth and rough channels.

Deterministic scour prediction equations for bridge abutments do not involve uncertainties coming from scouring parameters and they only consider effects of hydraulic parameters. However, in order to safely design bridge abutments, treatment of these uncertainties and evaluation of possible risks are required. Two artificial neural network (ANN) models are constructed to describe scouring phenomenon using the parameters of two different equations. The equation to be used in the reliability analysis is then determined according to ANN modeling results. To conduct reliability analysis, Monte Carlo simulation technique is used in which different distributions and coefficients of variations are used for random variables to examine their effects on reliability. It is observed that probability distributions of governing variables have no impact on reliability. However, coefficients of variations of these variables influence reliability.

Mini unmanned Air Vehicles (UAV) have high significance among other UAV&#039 / s, in different categories, due to their ease of production, flexibility of maintenance, decrease in weight due to the elimination of landing gear system and simplicity of use. They are usually built to meet &#039 / hand launching&#039 / and &#039 / belly landing&#039 / criteria in order to have easy flight and easy landing features. Due to the hand take-off and belly landing features there is no need to have a runway and this feature is a very significant advantage in operational use. In an operation, belly landing mini UAV&#039 / s may encounter tough landing areas like gravel, concrete or hard soil. Such landing areas may create landing loads which are impulsive in character. The effect of the landing loads on the airframe of the mini unmanned air vehicle must be completely understood and the mini UAV be designed accordingly in order not to damage the mini UAV during belly landing. Typical impact speeds during belly landing is relatively low (&lt / 10 m/s) and in general belly landing phenomenon can be treated as low velocity impact. The purpose of this study is to analyze the impact loads on the composite substructures of a mini UAV due to the belly landing. &#039 / G&uuml / vent&uuml / rk&#039 / Mini UAV which is designed and built in METU Aerospace Engineering Department, is used as the analysis platform. This study is limited to the calculation of stresses and deformation that is caused by the low velocity impact forces encountered during belly landing. The main purpose of this work is to help the designer in making design decisions for a mini UAV that is tolerable to low velocity impact loads. Initial part of the thesis includes analytical treatment of low velocity impact phenomenon. In the simplified analytical approach the loading is assumed as quasistatic and comparisons of such a simplified method of analysis is made with explicit finite element solutions on isotropic and composite plate structures to investigate the applicability of simplified analytical method of analysis. Belly landing analyses of the mini UAV are done by MSC.Dytran, which is an explicit finite element solver. Model building and post processing are done via MSC.Patran. Stress and deformation response of the mini UAV is investigated by performing low velocity impact analysis using sub-structure built-up approach.

Zeolite membranes are attractive materials to separate gas and liquid mixtures. MFI is a widely studied zeolite type due to its ease of preparation and comparable pore size with the molecular size of many substances. In this study MFI type membranes were synthesized over porous &amp / #945 / -Al2O3 supports and characterized with XRD, SEM and gas permeation measurements. In the first part of this study the effect of soda concentration of the synthesis solution on the membrane morphology and crystal orientation was investigated. The synthesis was carried out from solutions with a molar composition of (0- 6.5)Na2O:25SiO2:6.9TPABr:1136H2O at 150oC. At soda concentrations between 0.45 and 1.8 the membrane layers with (h0h)/c-directed orientation were obtained. At lower and higher soda concentrations membrane layer formed from randomly oriented crystals. The (h0h)/c-oriented membranes showed H2/n-C4H10 ideal selectivities of 478 and 36 at 25&deg / C and 150&deg / C, respectively.In the second part, MFI membranes were synthesized from mixtures with different concentrations of template molecules. Tetrapropylammonium hydroxide, tetrapropylammonium bromide or mixture of both types were used as template. The nucleation period, the size of MFI crystals, membrane thickness decreased as the tetrapropylammonium hydroxide concentration increased. Besides conversion of SiO2 in the synthesis solution to MFI passed through a maximum with increasing concentration of tetrapropylammonium hydroxide in the synthesis solution. When tetrapropylammonium bromide was used as template thicker membranes were obtained. In the third part MFI type membranes with a thickness of 1.5-2 &amp / #956 / m were synthesized by mid-synthesis addition of silica to the synthesis medium. The membranes synthesized with and without mid-synthesis addition of silica have n-C4H10/i-C4H10 ideal selectivities of 47 and 8 at 100oC, respectively. The change of composition during the synthesis increases the crystal growth rate and the size of the crystals forming the membrane, thus better quality membranes can be obtained by mid-synthesis addition of silica to the synthesis medium. In the last part of this study, thin MFI type zeolite membranes were synthesized in a recirculating flow system at 95&deg / C on the inner side of the tubular &amp / #945 / - alumina supports. A membrane synthesized by two consecutive synthesis steps had a separation selectivity of 38 and 86 for equimolar mixtures of n- C4H10/CH4 and n-C4H10/N2 at 25oC, respectively. The membrane selectively permeated large n-C4H10 over small CH4 and N2, suggesting that the separation is essentially adsorption-based and the membrane has few nonselective intercrystalline pores.

The purpose of this work is indicating System Dynamics Approach to be an appropriate tool for analysis of policies suggested for local sectors. Local sectors are very important for stability of the country&rsquo / s economy as well as welfare of the local community. Therefore, feasible and effective policies should be created and implemented in order to contribute to the local sectoral development. But before any policy implementation, policy analysis is required on to evaluate whether effectiveness and feasibility would be ensured in alternative policies. In this study, firstly the issues of Local Sectoral Dynamics and Policies are examined and specifically, the situation in Alanya Tourism Sector is studied. Afterwards, in accordance with policy analysis steps, problems of Alanya Tourism Sector are detailed and alternative policies that would aid in solution of the problem are idenfined. For evaluation of alternative policies, Dynamics of Alanya Tourism Sector are modeled by System Dynamics approach and the &lsquo / Formal Model&rsquo / is implemented in Stella 9.0.1. The model is simulated for all policy alternatives and the policy outcomes of each alternative are forecasted. Finally the performance of each policy are evaluated using the previously established criteria and combined policies having more superior outcomes than the present ones are created.

Roads are significant objects of an infrastructure and the extraction of roads from aerial and satellite images are important for different applications such as automated map generation and change detection. Roads are also important to detect other structures such as buildings and urban areas. In this thesis, the road extraction approach is based on Active Contour Models for 1- meter resolution gray level images. Active Contour Models contains Snake Approach. During applications, the road structure was separated as salient-roads, non-salient roads and crossings and extraction of these is provided by using Ribbon Snake and Ziplock Snake methods. These methods are derived from traditional snake model. Finally, various experimental results were presented. Ribbon and Ziplock Snake methods were compared for both salient and non-salient roads. Also these methods were used to extract roads in an image. While Ribbon snake is described for extraction of salient roads in an image, Ziplock snake is applied for extraction of non-salient roads. Beside these, some constant variables in literature were redefined and expressed in a formula as depending on snake approach and a new approach for extraction of crossroads were described and tried.

ABSTRACT FLEXIBLE ASSEMBLY LINE DESIGN PROBLEM WITH FIXED NUMBER OF WORKSTATIONS Barut&ccedil / uoglu, Sirin M.S. Department of Industrial Engineering Supervisor: Prof. Dr. Meral Azizoglu July 2009, 70 pages In this thesis, we study a Flexible Assembly Line Design problem. We assume the task times and equipment costs are correlated in the sense that for all tasks the cheaper equipment gives no smaller task time. Given the cycle time and number of workstations we aim to find the assignment of tasks and equipments to the workstations that minimizes the total equipment cost. We study a special case of the problem with identical task times. For the general case, we develop a branch and bound algorithm that uses powerful lower bounds and reduction mechanisms. We test the performance of our branch and bound algorithm on randomly generated test problems. The results of our experiments have revealed that we are able to solve large-sized problem instances in reasonable times.

The main objective of this study was to investigate the removal and recovery of nutrients from anaerobic digestion residues of poultry manure through struvite (MgNH4PO4.6H2O, MAP) precipitation. To this purpose, three sets of laboratory experiments were conducted. In the first set, separate and co-digestion of poultry manure and sewage sludge were studied in laboratory-scale mesophilic anaerobic batch reactors and subsequent struvite precipitation experiments were conducted with the reactors effluents. The effects of important parameters on struvite precipitation were investigated and it is illustrated that up to 89 % of NH4-N, 84 % PO4-P and 42 % COD removals were possible. In the second set, the effluents of a full-scale co-digestion plant utilizing poultry manure and maize silage were subjected to struvite precipitation experiments. Acidic phosphorus-dissolution process was successfully applied to the solid phase effluents to obtain phosphorus-enriched solution. By the addition of external Mg and P more than 90% of NH4-N and PO4-P were recovered from phosphorus-enriched solution, whereas the addition of only Mg led to partial recovery of NH4-N. In the third set, the effluents of a full-scale poultry manure digester were subjected to struvite precipitation experiments. The findings illustrated that Ca has inhibitory effects on the struvite reaction and lead to formation of hydroxlyapatite and amorphous calcium phosphates together with struvite. Based on the results obtained in this study, it is postulated that, struvite precipitation is a viable option for the recovery of the nutrients in the anaerobically digested poultry manure. This study illustrated that, poultry manure, if managed properly, could meet one-fourth of Turkey&amp / #8217 / s domestic fertilizer demand.

We aim to classify alternatives evaluated in multiple criteria among preference ordered classes assuming an underlying additive utility function. We develop a probabilistic classification method by calculating the probability of an alternative being in each class. We assign alternatives to classes based on threshold probabilities. We require the decision maker to place an alternative to a class when no alternatives satisfy the required thresholds. We find new probabilities for unassigned alternatives in the light of new information and repeat the procedure until all alternatives are classified. We implemented our algorithm to classify MBA programs among preference ordered groups. We evaluate our algorithm based on the number of misclassified alternatives and the number of alternatives placed by the decision maker.