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In this study, in which the adsorption of Cd(II) ions from aqueous solutions with the carbonization product obtained from the carbonization of paper mill waste sludge at different temperatures for two hours, it was observed that the adsorption efficiency increased with the increase of the carbonization temperature. The adsorption efficiency of Cd(II) ions depends largely on the pH of the environment. By contacting the 100 mg/L solution of Cd(II) with the carbonization product at 300, 400 and 500 °C at a dose of 5 g/L for 240 min at pH 5.5, the current Cd(II) ions were 45.3%, 52.4% and 61% removed. These values increased to 56%, 65.3% and 73.4% when the initial concentration of Cd(II) ions was taken as 50 Mg/L. When the dose was applied as 20 g/L for the initial concentration of 100 mg/L, all of the existing Cd (II) ions (except the carbonization product at 300 °C) were adsorbed. The results obtained for each carbonization product were applied to the Langmuir and Freundlich isotherms. The cadmium adsorption kinetics were defined with a second order model and the cadmium adsorption isotherm was determined to fit the Langmuir model better. The applicability of the results to the isotherm equations and the changes in the value of the isotherm constants depending on the carbonization temperature were examined. [ABSTRACT FROM AUTHOR]

In this study, paper processing residues containing a large extent cellulosic fibrous with inorganic filler such as calcite and clay minerals were used in the manufacturing of high density polyethylene (HDPE) composite. The residues ranging from 10 to 60wt% were loaded into HDPE in order to evaluate the effect of the paper processing residue filler on mechanical properties of HDPE. The composites were produced using mixing process by a high-speed thermo-kinetic mixer and molding process. Mechanical properties of the produced composites were analyzed using standard test methods. According to results, it was observed that the flexural modulus of composites increased with increasing filler contents. Especially, the flexural strength was increased by 26.3% for the 40wt% filler content. The tensile strength of paper industry mill residues filled HDPE composites exhibited an increase of 10-20% compared to that of HDPE matrix. Consequently, in the present study, paper processing residues filler without any modifying agent was used for the production of HDPE composites having better mechanical properties compared to HDPE. Thus, paper processing residues which have no economic value and cause an environmental problem have served as a filler material for HDPE. [ABSTRACT FROM AUTHOR]

In this study operating pressure driven systems which is known their efficiency in literature, for paper and pulp industry wastewaters in batch conditions were executed by using NFloose/NFtight membrane combination. The batch NFloose/NFtight experiments were respectively applied at 12 and 20 bars by conventional membrane filtration process, at a stirring rate of 300 cycle/min, at pH 10 and at a temperature of 25 °C. Determination of most suitable membrane at batch operating conditions were made by using 8 different membranes (for NFloose NP010, NFG, MPF36 and CK3001 and for NFtight NP030, NF270, DS-5DK, ESNA) through organic matter removal and filtrate flux values. In NFloose membranes at a filtrate flux of 4.12 L/m² h removal of 61.0% TOC and 76.9% COD and MPF36 membrane was determined to be best NFloose membrane. The filtrate water obtained by MPF36 were later passed through NFtight membranes. In all NFtight membranes generally the organic matter removal efficiency was good and ESNA was selected to be the best membrane in terms of effluent quality by obtaining organic matter removal at rates of 93.9% TOC and 94.2% COD with 10.05 L/m² h filtrate flux. From this point of view, in short term operation of paper wastewaters by pressure driven NFloose/NFtight integrated membrane system, it was seen that good quality of outlet water with 7.15 pH and a conductivity coefficient of 144 μS/cm and at 13 mg/L TOC and 28 mg/L COD concentrations could be obtained also that good quality of reuse water could be produced in terms of aimed effluent water. [ABSTRACT FROM AUTHOR]

Finite element analysis and computer-aided engineering methods have an essential role in modern research and development projects. Although proper element selection for the modeling type is critical for the accuracy of simulations, the selection process might be difficult for researchers in some cases where geometric conditions are challenging. The main objective of this paper is to present the differences in simulation results when three-dimensional cubic and two-dimensional quadrilateral elements are used for the modeling of spot-welded components. Following the modeling of shear specimens having two spot welds with different element types, static analysis, and high cycle fatigue simulations at three different dynamic load cases have been run within the context of this study. Displacement, stress values and tensors, as well as high cycle fatigue life have been evaluated as the output of analysis, and deviations due to different element types have been reported. Accuracy levels of different element types have been determined by comparing the life obtained by simulations with high cycle fatigue tests. The studies conducted within the content of this paper indicate that the rigid spot weld modeling with two dimensional quadrilateral elements give better consistency with the fatigue tests in comparison with the modeling with three dimensional cubical elements. The modeling procedures of correlated high cycle fatigue simulations have been detailed for spot welding, which is one of the most applied methods in aviation, automotive and marine industry. [ABSTRACT FROM AUTHOR]

Recently, researchers have started to be interested in population-based swarm-based algorithms in optimization due to their simple structure, high optimization performance, and ease of adaptation. Although swarm-based algorithms solve continuous optimization problems, they can also be used to solve binary optimization problems. In continuous optimization, the search space variables try to approach the optimal value, while in discrete optimization, the search space variables are fixed and expressed with real values. In binary optimization, the decision variables take values of 0 and 1 and are basically in the discrete optimization class. In this paper, the proposed Rat Swarm Algorithm (RSA) to solve continuous optimization problems is examined. RSA is an algorithm based on swarm intelligence. RSA was developed by imitating the chasing and attacking behaviors of rats. In this study, the original RSA was updated again to solve binary optimization problems and Binary RSA (BinRSA) was proposed. In BinRSA, four U-shaped and four T-shaped transfer functions are used while converting the continuous search field values to binary values. Thus, eight variants of BinRSA were obtained. These are named as BinRSA1, BinRSA2, BinRSA3, BinRSA4, BinRSA5, BinRSA6, BinRSA7 and BinRSA8. Among these variants, the most successful variant of BinRSA was determined as BinRSA6. Then the BinRSA6 variant was developed by adding crossover and mutation operators and was named GBinRSA. GBinRSA's performance has been tested in knapsack problems. In addition, the success of GBinRSA was compared with different heuristic algorithms selected from the literature. According to the results obtained, it has been seen that the solution quality of the proposed algorithm is effective and comparable. The results showed that GBinRSA is a preferred heuristic for binary optimization problems. [ABSTRACT FROM AUTHOR]

In this paper, membrane-based tubular liquid desiccant dehumidification system was designed, and its dehumidification performance was investigated. In the manufactured system, two different membranes, synthetic sausage casing and Tyvek® Solid were used. The air Reynolds number (Re) was varied during the experiments to investigate effect of air velocity on the system performance. In addition, temperature changes in the membrane were observed by images taken with thermal camera. According to the experimental data obtained, the dehumidification efficiency of the system was calculated in between 4.5-6% at 200 Re number for synthetic sausage casing and approximately 18.5% at the same Re number for Tyvek® Solid. [ABSTRACT FROM AUTHOR]

Recent studies show that the performance of Evolutionary Algorithms often depends on choosing appropriate parameter configurations. Thus, researchers have generally tuned these parameters either looking at the similar research areas in the literature or manually, e.g. Grid Search. However, searching the parameter manually is laborious and timeconsuming; therefore, meta-optimization techniques have become commonly used methods to adjust parameters of an algorithm. These techniques can be classified in two widespread manners: off-line, tuning parameters of an algorithm before the algorithm initiates, and on-line, tuning the parameters while it is working. In this paper, Bipolar Matching Tendency (BMT) algorithm has been chosen as the selection method of a Genetic Algorithm (GA). The new obtained algorithm is named GA-BMT and has been used for the first time as an online metaoptimizer. In addition, the paper utilizes two search algorithms (Grid Search, Coarse to Fine Search) with three meta-optimization methods (Standard GA, Particle Swarm Optimization, GA-BMT) to investigate the best parameter settings of the Standard GA for 17 test functions, and offers a comparative work by comparing their results. Furthermore, non-parametric statistical tests, Friedman and Wilcoxon Signed Rank, were performed to demonstrate the significance of the results. Based on the all results that achieved, GA-BMT presents a reasonable achievement. [ABSTRACT FROM AUTHOR]

Pedestrian traffic has less priority than vehicle traffic in Turkey’s transportation system. In recent years, there has been a growing interest in understanding pedestrians’ behavior. This paper investigates high school students’ (15-18 age range) gap acceptance behavior at unsignalized midblock crossings by designing a before and after study. The midblock crossing is conventional in the first situation. But after, the midblock crossing is raised. This paper aims to find the effect of raised midblock crossing on pedestrians’ acceptable gap behavior. In this study, a midblock crossing near a high school in Izmir City was chosen. Data was gathered by using two video cameras in the morning (7.00-8.00 AM). The obtained data were extracted from the footage. The data were analyzed by performing two-way and one-way analysis of variance (ANOVA). The legal crossing rate of the students increased with the installation of the raised midblock crossing. Also, average vehicle speed and 85th percentile speed determined for both situations. Thus, the number of acceptable gaps increased as well as the waiting time decreased significantly. [ABSTRACT FROM AUTHOR]

The importance and need for respirators has once again shown itself due to the coronavirus (Covid-19) epidemic, which has recently spread around the world and has been declared as a Pandemic (epidemic worldwide) by the world health organization. Monitoring respiratory activity plays a vital role in detecting respiratory diseases such as Chronic Obstructive Pulmonary Disease (COPD). In this study, a working group of 6 participants was formed to measure respiratory parameters. Each individual was provided to perform FVC, VC, MVV, RR and TV performance. The measurements were carried out simultaneously with the medical spirometer device. A total of 1860 data (1500 data for VC, 360 data for MVV) were sampled and all data were analyzed in Matlab program. It was observed that the results obtained were quite similar to each other (RMVV=0.998 for MVV; RVC=0.997 for VC). One of the most important contributions of this study is that the measured data can be sent to the computer and saved to the SD card. Thus, with the thermal printers in standard spirometers, paper wastage was prevented and the data was stored in digital environment. The developed system offers a practical and low cost solution. The developed device is expected to take an important place in biomedical device technology with its ability to measure COPD parameters. [ABSTRACT FROM AUTHOR]

This paper presents an analytical method to design proportional integral controllers for the stability, performance and robustness of third order plus time delay system models. Controller design is focused on providing desired gain and phase specifications of the controlled system by considering the frequency responses of an ideal system. Equations that give the parameters of the proportional integral controller which satisfy the mentioned properties are built step by step. These include the generalized equations for such systems. With the help of this method, the researcher can provide desired gain crossover frequency and the phase margin for third order plus time delay systems. Therefore, the Bode diagram can be relatively tuned and system performance and robustness can be improved. At the same time, stability of the system can be achieved with the proposed equations. Proposed controller parameters in this paper are applied on two different models. All results are shown graphically and on tables. [ABSTRACT FROM AUTHOR]

In this paper we classified 4 skin lesions (Melanoma, Melanocytic Nevus, Basal Cell Carcinoma, Benign keratosis) from ISIC 2019 dataset which was published by International Skin Imaging Collabration in 2019. We used InceptionV3 convolutional neural network model for classification. We applied two preprocessing methods: High Dimensional Model Representation (HDMR) and Hilbert Transform. In conclusion we obtained 89% accuracy on classification of Basal Cell Carcinoma using Hilbert Transform. Moreover, we obtained 78% accuracy on classification of Melanoma using Contrast Enhancement High Dimensional Model Representation (HDMR). [ABSTRACT FROM AUTHOR]

Spare parts inventory management is of vital importance in maintaining high equipment availability at minimum cost, especially for industries utilizing fully mechanized systems and aiming mass and continuous production such as mining. In this paper, it is intended to solve the spare parts inventory problem of a large-scale mining company operating in Turkey, by proposing a mathematical model to optimize the spare parts provisioning strategy in such a way that the total inventory related cost is minimized. Based on the current system analyzed and the real data provided by the company, a case study is conducted on inventory management problem of industrial lubricants, having a great importance in fully-mechanized systems to provide mass and continuous production. The optimization results show that the company's current lubricating oil inventory policy can be improved financially by yielding an annual saving up to ?18,566. [ABSTRACT FROM AUTHOR]

Today, engineers make efforts for post-graduate programs far more than before. The main reasons can be increasing awareness of firms about education, decreasing job opportunities for undergraduate degrees, the increasing demand for being an academician or scholarship opportunities by government. Some firms want their postgraduate student engineers to solve the firm's problems in their master or doctoral thesis as case studies. In this regard industrial engineering is a field that adjusts almost with every sector because of its multidisciplinary nature. Thus, there are many post-graduate theses written in this area. The aim of this paper is to analyze 2,122 postgraduate theses (master & doctoral) which are carried out in the department of industrial engineering in Turkish universities. The data is obtained from the website of Council of Higher Education of Turkey. The time period is determined as 2010-2017 and only the 1780 "permission" theses are analyzed in order to reach keywords for solution approaches and keywords analysis. Nine different indicators are used to analyze the thesis such as; university status, page numbers, language, keywords etc. As a result, this study shows how the theses are clustered according to different indicators and which topics are studied more frequently in recent years. The inference of the paper is important because the results give an insight about the road map of industrial engineering thesis completed in 56 different Turkish universities. [ABSTRACT FROM AUTHOR]

Austenitic 316LVM stainless are widely used in biomedical industry in particular medical surgical applications, and implant materials. In biomedical applications, especially implants used in the body are exposed to tribological conditions that cause wear behavior. Wear behavior of Implants fabricated by using these materials related to the surface conditions. One of the important processes influencing the surface properties used in fabricating process of implant is machining operation. For this reason, the effect of machining parameters and condition on the surface properties of this material and eventually altering the wear response is the focus of this current research. In this paper, dry milling operations of Austenitic 316LVM under various parameters were presented. The surface roughness, microhardness, microstructure are the examined surface integrity characteristics in this study. The effect of generated characteristics resulting from machining on wear resistance is measured using pin-on-disc test. It was revealed that cutting speed and feed has notable effect on surface roughness and strain hardening of the specimen. Increased strain hardening generally results in decreased wear resistance while increased surface roughness results in increased wear resistance. [ABSTRACT FROM AUTHOR]

Masonry historical monuments that connecting the past and the present are of major importance in terms of reflecting the knowledge and property of different cultures. This explains that why the protection of historic monuments is so important. The preservation of the historical monuments that constitute our historical and cultural heritage is only possible if they are examined in detail, their problems are solved and their solution methods and techniques are improved. One historical masonry mosque was selected to study in this paper. The mosque is modeled and analyzed by using SAP2000 finite element software in accordance with the dimensions of an architectural building survey. Seismic assessment of the monument was carried out via three-dimensional time-history dynamic analyses of the structure. Minimum and maximum values of displacements, base shear, and stress were interpreted, and the results were displayed graphically and discussed the earthquake motion was applied in two different directions which is X and Y. The seismic capacity of this building has been determined for varied earthquake grade. As a result of the analysis, displacements, stresses (tensile and compressive), base shear force were calculated under the effect of earthquakes. The Structural safety of the mosque was evaluated, and three-dimensional finite element analysis gave a general idea about the structural performance of the mosque. [ABSTRACT FROM AUTHOR]

Wind energy, which is a clean energy source and does not disrupt the natural balance, is today's one of the most popular renewable energy sources. In this paper, the factors which are utilized to determine a suitable site for wind farms have been analyzed by using the FUCOM (Full Consistency Method) method which is a relatively new subjective weighting method. FUCOM is a linear programming-based method and needs less pairwise comparisons than other weighting methods. The evaluation model in the study takes three main dimensions and twelve factors into consideration. The findings showed that the preference of a wind farm site depends largely on the wind potential and distance from residential areas. Furthermore, a sensitivity analysis was performed to demonstrate the consistency and usefulness of the suggested method. The results of this study could be used to determine the wind energy policy. [ABSTRACT FROM AUTHOR]

In this study, an air filter was manufactured and variation of temperature and vibration magnitude on filter paper were investigated experimentally by inverse pulse cleaning. For this purpose, compressed clean and dried air was released throughout in the inverse direction of the flow for 10 msec under 827 kPa constant pressure. The effect of nozzle and pulse distance for pulse cleaning of filter paper were observed experimentally under different nozzle-filter distance and different nozzle positions. The magnitude of vibrations and variation of temperature obtained using accelerometers and thermal camera respectively. The usage of nozzle within the different positions and distance effect vibration and temperature patterns. As a result of experimental study, it was determined the most homogeneous vibration and temperature distributions were at vertical position of nozzle. [ABSTRACT FROM AUTHOR]

Supply chain risk management (SCRM) is crucial for a long-term profitable, competitive and sustainable supply chain. Many destructive risk incidents that have affected the global scale have come into play in the historical process. The losses, occurred due to these risk incidents, revealed how the supply chains are fragile against the risks. In this study, a comprehensive supply-side literature review has been conducted on SCRM. In order to define the conceptual framework of SCRM, 59 studies from the years 1999-2016, and 137 supply-side studies from the years between 2003 and 2016, in which quantitative methods had been utilized, have been determined. All 196 studies have been reviewed, and analyses and suggestions have been provided. This study, in general terms, differs from the previous review studies by outlining all aspects of the conceptual framework of SCRM, surplus of the reviewed paper, including papers published after 2013, and extend of review coverage. [ABSTRACT FROM AUTHOR]

In recently, the design of modulator algorithms for wireless communication systems by using digital circuits is widely realized. Moreover, it is crucial that resource utilization of the selected algorithm is reduced. In this paper, a modulator architecture which has lower RAM bit that of conventional BPSK is proposed for BPSK (Binary Phase Shift Keying) modulation technique that is used widely in wireless communication systems. The architecture can achieve to save RAM bit utilization by up to 87.5% with respect to conventional BPSK. In addition, a real-time message signal is applied on ADC (Analog to Digital Converter) which is integrated on Altera DE-0 Nano FPGA (Field Programmable Gate Array) in the paper. It is shown that proposed structure is practically realizable by achieving of message signal in output of DAC (Digital to Analog Converter) after modulation and demodulation processes. [ABSTRACT FROM AUTHOR]

Fossil fuels generally meet the energy demand of internal combustion engines. Due to the run out fossil fuels day by day, renewable energy sources catch the researchers' attentions. Biogas is a renewable alternative fuel produced from organic wastes. In this paper, the effect of diesel fuel amount on the exhaust emissions of the biogas-diesel dual fuel engine was investigated. Experiments were carried out on a four stroke, four cylinder, water cooled, turbocharged, common-rail diesel engine. No changes were made on original settings of electronic control unit of the engine. The energy demands of dual fuel engine were supplied by diesel fuel about 20%, 30%, 40% and 50%. All tests were conducted at 1750 rpm constant speed, 40 Nm, 60 Nm and 80 Nm engine loads. Depending on increasing diesel fuel amount, HC, CO2 and NOx emissions decreased but soot emissions raised. The increase in the amount of biogas sent to the cylinders increased both the amount of fuel burned in the premixed combustion phase and the NOx emissions. The CO2 contained in the biogas increased HC and soot emissions by diluting the fuel-air mixture. [ABSTRACT FROM AUTHOR]

This research covers investigation of mode-I fracture toughness of the recycled waste mussel shell particles reinforced epoxy composites. Vacuum assisted resin infusion molding (VARIM) method was applied to produce composites. The aim of the research is to use recycled waste shells to reduce production cost and to prevent environmental pollution. VARIM was applied to produce fiber reinforced composite. Therefore, as reinforcement particles mussel shell, and as particle reinforced composite production method VARIM are both two new points of the research. Mode-I fracture toughness experiments conducted according to ASTM D 5045 standards with single-edge-notch bending specimens for six repeats. According to mode-I tests, the fracture toughness of the mussel shell particle reinforced epoxy composites is 2.44 MPa∙m1/2. The failure region from one of the tested specimen was investigated by scanning electron microscope (SEM) in the next section of the paper. After the test results are given by diagrams, they are discussed according to other particle-reinforced composites to show the new material place in the literature by means of fracture toughness. [ABSTRACT FROM AUTHOR]

Treatment of arsenate from groundwater by electrocoagulation (EC) reactor with air supply unit using Al ball electrodes were studied in this paper. Influence of some operating variables, for instance, applied current (0.075-0.3 A), initial pH (5.5-8.5), air flow rate (0-6 L/min), size of Al ball electrodes (5-10 mm), and height of electrode in EC reactor (2-8 cm) on the As(V) removal efficiency were evaluated. The As (V) removal efficiency increased with the increment of applied current, air flow, electrode altitude in EC reactor, and EC time while its removal efficiency decreased with the increment of size of Al ball electrodes. The maximum As(V) removal percentage, minimum operating cost and energy consumption were found as 98.68%, 0.609 $/m3 and 3.7694 kWh/m3 at pH of 7.5, current density of 0.30 A, size of Al balls of 7.5 mm, height of electrode in EC of 5 cm, and air flow rate of 6 L/min, respectively. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the nonlinear behavior of space truss roofs subject to different load accumulation forms considering the effect of initial imperfection and slenderness ratio of the truss members. For this, a typical space truss roof using MERO-connection type with flat double-layer was selected as a sample. 3D model of the roof was developed and analyzed by using OpenSEES. Nonlinear behavior of each typical bar of the space truss roof, which, was mainly composed of particular sub-elements such as a tubular element, bolts, sleeves and spheres was represented by a single truss bar. Axial load-displacement relationship of each single truss bar was obtained from nonlinear analysis performed under reversal cyclic loading. Besides, three different types of load distribution that simulates accumulation of rainwater or drifted snow were taken into account as an external load acting on upper layer of the roof system. Analyses results showed that load carrying capacity of the space truss roofs was susceptible to the form of accumulation and reduces abnormally when the accumulation, in particular, occurred locally. Furthermore, failure mode of the system designed with optimal solution was dominated by buckled truss bars and brittle failure occurred. Also initial imperfection had a negative effect on the members in compression. [ABSTRACT FROM AUTHOR]

In this paper, solid particle erosion behaviors of AISI 1020 steel and Ti-6Al-4V titanium alloy materials were experimentally and numerically investigated. Experiments and numerical simulations were carried out for the conditions of different particle impact velocities (100, 127, 170, 210, 250 m/s) and angles (20, 30, 45, 60, 90‹). Moreover, erosion performances on the erosion shield of a helicopter rotor blade of aforementioned materials were numerically determined for the condition of angle of attack of 0. and impact velocity of 230 m/s. Numerical erosion analyzes were performed with ANSYS_Fluent 15.0 package program using discrete phase method with Eulerian- Lagrangian approach and an empirical erosion equation while experimental erosion tests were conducted by MIL-STD-3033 standard. As a result, numerical results were in good agreement with the experimental data, and it was obtained that erosion performance on the shield surface of AISI 1020 steel material is better than Ti-6Al-4V titanium alloy material. [ABSTRACT FROM AUTHOR]

In a Wireless Sensor Network (WSN), system resources, such as the total node energy, need to be utilized effectively while executing the task of interest. Since a number of sensor nodes may be needed in various type of applications, it is also important to develop each sensor node in a cost effective manner. The purpose of this paper is to develop a custom made, low power, cost-effective wireless sensor node based on a MSP430G2553 microprocessor and nRf24l01+ wireless transceiver module. Then, using these nodes, we form a simple WSN testbed, and locate the position of a light emitting source. [ABSTRACT FROM AUTHOR]

In recent years, the research on activity recognition has gained speed especially with the development of smart phones and wearable devices. Activities could be categorized into two main groups. simple activities such as walking, running and complex activities such as eating, sleeping, brushing teeth. In this survey paper, articles about activity recognition are examined thoroughly. Sensors and devices used in activity recognition, types of daily activities, application areas, data collection process, training methods, classification algorithms and resource consumption are mentioned in details. The state of the art is elaborated and the existing methods are compared to each other. Later, open data sets are mentioned and studies offering innovative solutions using latest approaches such as deep learning methods are introduced. Finally, still open issues on this area are presented and future work has been discussed. [ABSTRACT FROM AUTHOR]

Time delay is a control system design factor, which reduces the performance of the system and makes the system unstable in the worst case. Many methods have been proposed in the literature for time delay compensation and the Smith predictor is the most widely used. Although the Smith predictor is easy to implement, the delay compensation performance degrades as the time delay model used by the predictor differs from the actual time delay in the system. Communication disturbance observer has been proposed as an alternative method to the Smith predictor and it has been applied to the bilateral teleoperation systems, robotic manipulators and network-based gait rehabilitation systems. This paper deals with the application of communication disturbance observer to the vehicle yaw stability control. The performance of communication disturbance observer is tested for time varying delays by using several simulations and the results are compared with the Smith predictor results. [ABSTRACT FROM AUTHOR]

Nowadays, an approximate mathematical model of the brain cortex has been used for the treatment of the first epilepsy and Parkinson, and several diseases. It is assumed that the mathematical model of the cortex is an exact model. However, due to the time-varying parameters, noise and other disturbances, this model is not always valid. Moreover, since it is difficult and expensive to measure some states, software based solution is aimed here. Consequently, in this paper, state and parameter estimation of the brain cortex model are jointly achieved using nonlinear observers of different characteristics. The state estimation of the model was merely performed in [1]. As the nonlinear observers, extended-Kalman filter (EKF), sliding-mode observer (SMO) and discretization based gradient observer (DBGO) approaches are designed. The estimation of unmeasurable states and parameters are performed both for the epileptic and normal state of the mathematical model since the cortex model has normally nonlinear dynamics but it exhibits chaotic behavior in epileptic state. Therefore, the estimations are provided for first normal state, then epileptic state. In computational results, it is observed that the designed nonlinear observers resulted successful estimations for unmearuable states and parameters. The estimation results and estimation performances are given to compare the nonlinear observers for noisy and noiseless cases. [ABSTRACT FROM AUTHOR]

In this paper, an adaptive backstepping controller is designed where the road disturbance is assumed that it is not measured. Therefore, the disturbance is modelled as a sum of sinusoidals where amplitude, phase and frequency are considered as unknown. Then, the observer is parametrized. After the design of the observer, an adaptive controller is designed with using backstepping technique. It is proven that the closed loop system is stable and the acceleration of the body is attenuated under the effect of the road disturbance. To reveal the performance of the controller, a simulation is illustrated with road test. [ABSTRACT FROM AUTHOR]

In this paper, kinetics of extraction of total polyphenols from Zingiber officinale was investigated. Samples were extracted using water at different temperatures and the extraction was realized under mixed and unmixed medium to observe the changes in the kinetics. Four different models, namely Peleg, Mass Transfer, Logarithmic and Page's Models, were used for mathematically describing the physical behavior of the extraction. The yields of polyphenols determined as gallic acid equivalents ranged between 2.29-5.23 mg/g depending on the temperature and mixing conditions. Peleg's model, having the highest regression coefficients at all conditions investigated for steady-state conditions, and Mass transfer model for unsteady-state conditions were found as the best fit to the experimental data. Also, molecular and convective diffusivities and activation energy of extraction were evaluated in this study. It was found that increase in temperature and mixing rate increased the diffusion coefficients because they decreased the activation energy of extraction. It has been found that temperature was much more effective than mixing rate, on the process. [ABSTRACT FROM AUTHOR]

Biogenic amines mainly occur by microbial activity in high-protein foods and fermented foods and have important health effects, but may cause toxicological effects at high concentrations. For this reason, the factors influencing microbial growth also affects production of biogenic amines. The factors that affect the formation of biogenic amines are carbohydrate concentration, pH, temperature, sodium chloride concentration, types of microorganisms in the foods, starter cultures, oxygen and so on. While biogenic amines can react with nitrosating reagents such as nitrite and nitrogen oxides to form carcinogenic nitrosamines, they are also able to transform from one biogenic amine form to another. In addition, some polyamines could produce toxic acrolein by their catabolism with polyamine oxidase. The aim of this paper is to give information about the occurrence and formation mechanisms of biogenic amines, factors influencing their formation, and transformation of biogenic amines to other compounds. [ABSTRACT FROM AUTHOR]

In this paper, a wideband microstrip bandstop filter design having a compact size is proposed. The proposed filter is designed by making a capacitive loading to the bottom side of a meandered open loop resonator formed by folded microstrip transmission lines. Input-output ports are connected to each other with a high impedance transmission line and capacitive loading is achieved by interdigital capacitors to this transmission line. In the designed filter, high selectivity can be obtained by means of reflection zeros occurred at the upper and lower frequencies of the stopband. Control of those reflection zeros is achieved by the changes in various parameters of the circuit. Besides, there are two transmission zeros inside the stopband. Bandwidth and center frequency of the stopband can also be controlled. In order to prove the validity of the proposed study, the designed filter was fabricated on an RT/Duroid substrate having a dielectric constant of 10.2 and a thickness of 1.27 mm. Measured results of the filter with a center frequency of approximately 2.57 GHz and a bandwidth of 1.22 GHz have been observed in a very good agreement with the simulated results. In the measurements, return loss and in-band insertion loss have been obtained as -0.3 dB and better than -20 dB, respectively. [ABSTRACT FROM AUTHOR]

In this paper, flow changes were observed via Particulate Image Velocimetry (PIV) technique in shallow water flow for two side by side circular cylinders which a vertically placed splitter plate (VSP) was placed between them. The circular cylinders made of acrylic material have a diameter of H = 40 mm. Throughout the experiments water height was hw= 20 mm and flow images were taken at the elevation of ℎL= 10 mm. The free stream velocity was U∞ = 125 mm/sec and Reynolds Number wasReD = 5000 based on diameters of circular cylinders. Five different VSPs varied from heights of H= 2 mm to 10 mm with an increment 2 mm were used to control unsteady flow. The gap/diameter ratio was G/D= 1.25 for all cases. Dimensionless Turbulence Kinetic Energy values and time-averaged velocity vectors were acquired by processing experimentally obtained data on a computer. As a result, the usage of splitter plate has shown its effectiveness on flow control. After the plate height of H = 6 mm, TKE values were decreased significantly. The most effective plate height onthe flow control was seen as H= 10 mm. [ABSTRACT FROM AUTHOR]

Electrical-electronic waste (WEEE) is generated from electric and electronic devices at the end of their lifecycles. When WEEEs are disposed, burned or disassembled for recycling, they are transformed into products containing hazardous substances and harm the environment and human health. Therefore WEEEs should be collected, transported and processed properly during their recycling operations by municipality authority in order to minimize their damage and maximize their economic benefit. In this paper, a study is carried out for the WEEE management of Çankaya Municipality by the cooperation of Environmental Conservation and Control Department of Çankaya. For this purpose first WEEE with a focus on television, refrigerator, washing machine, oven and vacuum cleaner are estimated based on the electronic device usage behavior of residents in Çankaya. Secondly, the WEEE collection points' location problem is solved considering set covering problem. [ABSTRACT FROM AUTHOR]

The intense competition in the production of particleboard in the world requires minimization of process times which is one of the important parameters effective on costs. In this study, it is aimed to minimize the press time in order to increase the production speed by using the mathematical sub-structure of the response surface method (RSM) which is one of the well-known design of experiments techniques. For this purpose, optimum levels of the factors those have effect on press time namely humidity of the particleboard, bath gel time, gravure gel time for the bottom of the particleboard, gravure gel time for the top of the particleboard, flow, final weight, humidity of the paper, amount of urea-formaldehyde (UF), amount of melamine formaldehyde (MF), press density, press pressure and press temperature were investigated. In this case, It is aimed to increase the production amount and productivity of the line while decreasing the press time. For the purpose of modeling, the mathematical relationship between the factors and the press time was determined by using 56 observation values of 5 repetitions each and then optimization was performed. At the end of the study, the press time is reduced to 11 seconds from 13.57 seconds-which is the lowest press time observed for the currently selected item type. [ABSTRACT FROM AUTHOR]

The most significant disadvantage of membrane processes is considered to be concentrated flow. In classical membrane processes where the driving force is pressure, a concentrated flow of 10-35% occurs. Similarly, in electrodeionization processes, where the driving force is electricity current, a concentrated flow of 10% is known to occur in practice. In this paper, studies were conducted on the reutilization of the concentrated part. Thus, the concentrated part was reduced to 0.5% and 1% in the classical electrodialysis and bipolar membrane electrodialysis processes, respectively. Furthermore, considering that the concentrated flow in the process is acidic and alkaline solutions, these solutions were concentrated. In consequence of the acid concentration process carried out in relation to the contaminant ion 0.01 M H and 0.01 M OH ion concentrations, an ion concentration of 0.72 M H could be achieved. Similarly, OH ion concentration rose to 0.5M. Thus, minimization of the concentrated part, one of the most important problems encountered in membrane processes, could be ensured simultaneously. Moreover, quite acidic and alkaline solutions were obtained simultaneously. [ABSTRACT FROM AUTHOR]

Nonlinear dynamical model and its physical quantities have to be known exactly in order to obtain a high performance in the speed control of brushless direct current (BLDC) motors. However this may not be possible due to the lack of knowledge on the model parameters, the change of some physical characteristics during the operation and uncertainty on the load torque. An adaptive backstepping controller design is proposed in this paper to provide the speed control under parametric uncertainties. Model uncertainties have been considered in the design process of the controller and the convergence of the speed error to zero has been ensured via Lyapunov stability analysis. The designed controller has been tested for various reference trajectories considering all the practical issues in a simulation environment and satisfactory results have been obtained. [ABSTRACT FROM AUTHOR]

Microorganisms are small organisms as we cannot see with the naked eye. Microorganisms that play a role in the ecological balance are mainly composed of bacteria, fungi, algae, viruses and protozoa. The medium and petri dish are used in order to provide the growth medium to microorganism by mixing agar and other nutrients for performing operations such as isolating from the environment, growth, counting of microorganisms. The number of microorganisms may reach the million or even more by reproductively, in this way they form structures called colony which can be seen with the naked eye. In terminology, this structure expressed as colony forming units (cfu). Mold on the cheese, bread, fruit or yogurt, yeast on the sugar-containing foods such as chocolate, marmalade are colonies formed by grown microorganism. Colonies formed on the agar, create images of different morphological characteristics depending on the microorganism and growth media. In this paper, classification of microorganism is performed from the colony images by image processing and pattern recognition techniques. [ABSTRACT FROM AUTHOR]

Landfilling is the most widely used method for the waste treatment. As experienced in other solid-waste landfills, leachates are generated during the decomposition of the garbage buried and as a result of the percolation of rainfall through the landfill. Landfill leachates consist of a complex mixture of organic and inorganic components which can contain toxic and hazardous contaminants. Due to the wide variation in the characteristics of the leachates, there is no unique way for their treatment. Therefore, the effective treatment of landfill leachate usually requires a combination of various physical, chemical and biological technologies. Up to now, electrochemical process has been proved to be promising for wastewater treatment mainly due to its high effectiveness and easy operation. This study investigated the efficiency of electrocoagulation in removing total nitrogen (TN), chemical oxygen demand (COD), total organic carbon (TOC) from leachate. The paper studies the factors affecting the efficiency of removing these parameters of leachate, such as amount of electrode material, current density, electrolysis time. The sample of leachate was supplied from Aksaray Landfill Site in Aksaray. In experimental studies the optimal duration was determined to be 30 minutes for COD. The removal efficiencies of COD %83, with two electrodes for 5 V at 30 minutes. 120 minutes were accepted as the most suitable reaction time for total organic carbon. The increase in the operating time was found to have a lesser effect on the total nitrogen recovery efficiency. All the findings of the study revealed that treatment of leachate by electrochemical process can be used as a step of a joint treatment. [ABSTRACT FROM AUTHOR]

With the developments in the construction sector, the use of fiber in concrete technology has gained great importance due to the developments of the spread of high rise concrete buildings, the increasing importance given to infrastructure, investments in nuclear energy field. Therefore, it is clear that this fiber reinforced composite especially should have also ductility properties. Fiber reinforced composites are designed in order to prevent extremely structural collapse by absorbing massive amount of energy during extreme loaddisplacement events such as earthquakes, projectile impacts and explosions. It will be much more possible with using this composite in the construction sector to construct much higher concrete building, increase the economic life and strength of important infrastructure members, construct more secure containment buildings which is important for the safety of nuclear power plant, reduce the section and reinforcement ratios in reinforced concrete structural members. In this regard, in the concrete technology in order to provide the above mentioned composite properties, the significance of fiber usage has increased. It was found from studies made that it is possible to produce more developed composites using hybrid fiber having different properties with single or different fiber combinations. In this paper, the significance of the use of fiber for producing the cementitious composite, fiber types and the using forms (single or hybrid) and the effects of micro and macro fiber types on the engineering properties of the hybrid fiber reinforced composites are investigated. Finally, at construction sector the use of hybrid reinforced composites has gained great importance due to the formation of multiple crack and high tensile strength. [ABSTRACT FROM AUTHOR]

One of the most important issues of studies that have been done on the power systems is loss reduction. Flexible A. C. transmission systems (FACTS) give significant opportunities to realize this aim. Static Synchronous Compensators (STATCOMs) are the most flexible and sophisticated structure as compared to the other FACTS devices in terms of operation. Total losses of a power system change according to the location and reactive power output of STATCOM. In this work, it is aimed to find optimum location and output value of a STATCOM that provide minimum losses of power system by using four different heuristic algorithms and to compare these algorithms. Heuristic algorithms that are used in this paper are Gravitational Search Algorithm (GSA), Particle Swarm Optimization (PSO), Artificial Bee Colony (ABC) and Ant Colony Algorithm (ACA) respectively. These methods were applied to IEEE-14 bus test system, and optimum locations and output values of STATCOMs that provide minimum losses have been found. Also, results of all methods are compared and discussed in terms of finding proper value and convergence speed. [ABSTRACT FROM AUTHOR]

In this paper, an object detection approach suitable for mobile augmented reality is presented. The baseline approach is based on matching keypoint descriptors and verifying these matches with geometric constraints. The performance optimizations necessary for speeding up matching are detailed. It is also demonstrated that it is possible to increase the performance of the Locality Sensitive Hashing by exploiting approaches from the information retrieval field. [ABSTRACT FROM AUTHOR]

Today's newly constructed buildings are being turned into intelligent homes, by the addition of embedded systems into them. In order to provide advantages similar to intelligent home users in our country, relatively lower cost intelligent entry door solutions are being offered to middle class consumers, as in other countries. In present work, a new intelligent door accessory is proposed which increases the security and functionality of both new and already installed doors. Our work involves embedded system hardware and software components. The proposal is supported by a prototype design based on the Arduino platform and a concrete pilot application. The software part contains both a server and a client application. In brief, the system provides the house owner with the opportunity to remotely meet the person knocking at the door and the advantages of obtaining in advance information about visitors, by sharing preferred information reciprocally with other social group members. The presented design is not only a concrete example for Internet of Things technology, but it also turns the social media frenzy into an advantage. In this paper, the tests conducted on a system produced according to the proposed design and the test results are also presented. The proposed solution is compared with similar solutions. The comparison results are discussed and the planned future work is put forward, after the conclusion. [ABSTRACT FROM AUTHOR]

In this paper, effectiveness of heated tube with conical baffles was studied experimentally as a function of various inclination angles. By using inclined conical baffles vortex of the flow was increased thereby giving rise to heat transfer and the best inclination angle was determined. Experiments were performed for three different inclination angles (45°, 60° ve 80°). Water as hot fluid and air as cold fluid were used as working fluids in the experiments. Water temperature was fixed as 65 °C. Air flow velocities were taken at 8 distinct levels between 2-20 m/s. The results indicated that for NTU>1, 45° and 80° were more effective compared to 60°. In addition for NTU<1, all three angles were found to be similarly effective. [ABSTRACT FROM AUTHOR]

In this paper, wind energy potential of Sakarya University was evaluated. In the study of wind energy potential assessment for Sakarya University, topography, obstacles, roughness data of the region with wind data obtained from Esentepe wind measurement station were used. Calculations were made by using WAsP (Wind Atlas Analysis and Application Program) software and other wind energy analysis software. Some advices were given to possible wind energy investors by evaluating the results obtained for different heights. [ABSTRACT FROM AUTHOR]

The timetabling of courses and examinations is a challenging and time consuming activity for all educational institutions, especially universities. The course scheduling problem is a type of timetabling problem that is concerned with assigning a number of courses and instructors to the most suitable classrooms and time-slots, subject to some constraint structures on characteristics of the problem and institutions. In this paper, we analyze the main points of the outstanding studies that have conducted on the problem since 1960. In addition, solution approaches that have been applied by researchers to solve the problem, including operations research based methods, metaheuristicbased methods and some novel methods are analyzed. [ABSTRACT FROM AUTHOR]

This paper presents a design method for Two Degrees of Freedom control structure with Fractional Order PID controller using stochastic multi parameter divergence optimization algorithm. This control structure is applied to feedback, feed-forward and component separated type control loops and controller parameters are obtained with the optimization algorithm. Then, the performance of the three various control loops are compared. [ABSTRACT FROM AUTHOR]

In this paper, we examine the multi-equilibrium consensus problem for a network of n agents having fixed or time-varying communication links. We introduce necessary and sufficient conditions on networks modeled with undirected graphs such that multi-equilibrium consensus states are achieved, thus extending the classical convergence results in the literature. Spectral graph theory and switched systems theory are used to analyze the continuous-time algorithm. Theoretical results are verified by simulation studies. [ABSTRACT FROM AUTHOR]

In this paper, position control application of DC servo motor is investigated by using conventional model reference adaptive control structure with fractional order integrator. Modification of the controller is achieved by fractional order integrator in adaptation rule. Object position for reference input of control system is updated in real time by the values obtained from camera of object tracking system. Results obtained for integer order integrator and fractionalorder integrator for model reference adaptive control system are compared and it is observed that the fractional-order integrator can provide faster adaptation for the system. [ABSTRACT FROM AUTHOR]

The effect of the unmodeled dynamics and unknown disturbances prevent the accurate control of the real-time systems. The designed controllers must undertake the effect of these undesired uncertainties. In this paper, adaptive uncertainty modeling based model predictive controller is proposed for the control of uncertain linear systems. The uncertainty modeling structure uses an artificial neural network with adaptive learning rate for fast approximation. The stability of the proposed adaptive uncertainty modeling based model predictive control (UMPC) is shown using Lyapunov candidate function. Conventional MPC and proposed UMPC are applied to the control of a real-time DC/DC buck power converter. The conventional MPC cannot accurately control the DC/DC converter due to the unknown parameters and unmodeled dynamics. However, the proposed UMPC controller can accurately control the system with modeling the uncertainties in controller dynamics. The proposed controller is promising to control uncertain systems in future applications. [ABSTRACT FROM AUTHOR]