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Shape memory alloys’ characteristics are different from ordinary materials because they can memorize their pre-determined shape, thus they are excellent candidates for different applications. In this review article, the most interesting parameters that researchers are using in their investigation have been highlighted. Also, the popular techniques used for the characterization of shape memory alloys have been described. The diagrams and sketches can show a clear view of metallurgies and related research areas.

In this paper, a remotely controllable, differentially driven wheeled mobile robot was developed in order to build 2D maps of unknown indoor environments; this system would eliminate the need to pre-explore such environments. Main aim of the study is to develop a system with high accuracy by using minimum number of sensors and a processor with low cost especially for comparatively small indoor areas. The distance traveled was calculated using the wheel odometry method. Obstacles surrounding the robot, the distance traveled, and the robot’s orientation were obtained using an ultrasonic distance sensor, optical encoder, and a 3D orientation sensor (also known as an Attitude and Heading Reference System –AHRS), respectively. In addition, the characteristics of the system hardware components were empirically explored, and the errors resulting from the sensors were evaluated. The non-linearity percentage error arising from the encoder was defined and then compensated for. The hysteresis behavior of the ultrasonic distance sensors was also empirically tested. All of the tasks were conducted by using a low-cost FPGA (Field Programmable Gate Arrays) board. This study used the graphical development platform, National Instruments (NI) LabVIEW, and it’s FPGA Module which is used for programming of embedded systems instead of the text-based HDLs (Hardware Description Languages). This distinguishes the proposed system from similar prior studies.

Power Quality problems, which have become an important consumer issue in recent years, are defined as changes in voltage, current, or frequency in the power system. Among the factors affecting energy quality in grid-connected PV systems are island mode operation, current and voltage harmonics, transients, flicker, interruption, DC offset, notches, frequency changes, voltage sag / swell, voltage imbalances in the system and power factor. Because of the power quality problems, several transmission and distribution losses can occur due to both the consumers and the generators. Also, the integration of PV power plants to the main grid will cause several power quality problems, and a reliable operation of the grid with PV power plants is a significant issue for distributed generation. Thus, the first step in preparing a reliable algorithm for detecting power quality events occurring in the current grid is to model a power system in which power quality impairments can be analyzed. In this work, the power quality disturbances that occur in the low-voltage grid that is fed through both the main grid and the grid-connected PV system are modeled and investigated. Developed electric power distribution model includes simulation of voltage sags caused by three phase fault, transformer energization and asynchronous motor switching, voltage swells caused by three phase fault, transients due to large capacitor bank switching, harmonics and notches caused by the load connected via the power converter. Examination of the power quality disturbances with simulation clearly revealed the resulting waveforms, the response of the electrical power system to the fault conditions. Another advantage of the realized study is that the developed model can be used to measure the performance of the PV connected distributed generation system in fault detection and classification studies.

The necessity for reduction of fossil fuel consumption and the increasing energy costs drives the interest in development of alternative renewable energies during past years. OFMSW (Organic Fraction of Municipal Solid Wastes) is a valuable source, while it can be converted to biogas via anaerobic digestion. In this study The anaerobic digestibility and methane generation potential of the organic fraction of municipal solid wastes (OFMSW) sampled during three seasons (autumn, winter and summer) of a year were determined using batch bioreactors with varying initial dry solid matter ratios (DM:5-35 %). Batch experiments were carried out both with and without anaerobic inoculum. On the basis of the laboratory results, biogas production potentials were determined to be in the range of 229 - 484 m3/tonDM for experiment using anaerobic inoculum and 84 – 176 m3 /ton DM for experiments without inoculum. The best organic matter combination belongs to autumn season and the best concentration was observed as 20% DM.

In this study, the buck converter circuit which is the topology of the power electronic circuit has been investigated to obtain the desired output voltage. The state variable of the circuit that is also used output of the system have been optimally controlled. The PI controller which is the basic structure and widely used in the practical applications has been run in discrete time. The PI controller parameters can be calculated by using a method based on the rootlocus, pole placement or Ziegler–Nichols method. However, these methods can not provide a solution with highe fficiency signal output voltage. In order to obtain the minimal cost value of the control process, Kp and Ki control parameters are optimized by using the Fire Fly (FF) algorithm based on swarm intelligence. The Matlab-Simulink program has been utilized for the simulations. The results show that the FF algorithm may observe the optimal values for the controller parameters.

Günümüzde trafik kontrolsistemlerinin verimli çalışabilmesi için kısa dönemli trafiğin tahmin edilmesigerekli olmaktadır. Bu çalışmada, Kırıkkale İl sınırlarındaki (D-200, E88) karayoluna ait kısadönemli trafik tahmin modellerinin geliştirilmesi için dönemsel otoregresifbileşik hareketli ortalama (SARIMA) tekniği kullanılmıştır.. Modellemedekullanılan veri seti, yolun 29+100 km’ sinde belirlenen kesiminde, yaklaşık 2ay süre boyunca 15 dk.’ lık zaman dilimleri şeklinde yapılan sayımlardan herbir şerit için ayrı olarak elde edilmiştir. Elde edilen trafik akımı verilerinin%80’ i SARIMA modellerinin oluşturulması için, kalan kısmı ise modelintahminlerinin test edilmesi için kullanılmıştır. Farklı tiplerdeki SARIMAmodelleri iki şeritli karayolunun sağ ve sol şeritleri için oluşturulmuştur. Analizlersonucunda SARIMA(1,0,1)(0,1,1)672 her iki şerit için en düşük tahminhatalarını üretmiştir. Modellere ait R2 değerleri ise sağ şerit için0,92, sol şerit için 0,88 seviyelerinde olduğu hesaplanmıştır. Modellerinyüksek R2 değerleri ve düşük hatalar üretmesi nedeniyle geliştirilen SARIMAmodellerinin Türkiye karayollarının kesintisiz akım koşullarını sağlayan yolkesiminde Türkiye'de kullanılabileceğini anlaşılmıştır., Nowadays, forecasting short-term traffic isnecessary for traffic control systems to serve efficiently. In this study,short-term traffic forecasting models were developed using seasonalautoregressive integrated moving average (SARIMA) technique for the highway(D-200, E88) in Kırıkkale border. The dataset for modeling were collected foreach lane with 15 min periods from the road section which is in 29+100 km onthe highway for two months. The 80% of data were utilized to develop SARIMAmodels and the rest of the data were used for testing the models. As a resultof the analyses, SARIMA(1,0,1)(0,1,1)672 produced the lowest forecasting errorvalues for both lanes. The R2 values of the models were calculated about 92% forright lane and 88% for left lane. The models generated high R2 values and lowerrors, therefore developed SARIMA models can be used on uninterrupted roadsections in Turkish highways.

Atıksularında bulunan farmasötiklersucul canlılar üzerinde oldukça toksik olmaları nedeniyle büyüyen bir endişehaline gelmektedir. Atıksularda ve yüzeysel sularda farmasötiklerinkonsantrasyonları µg/L ve ng/L gibi çok düşük seviyelerde olmasına rağmenbunların kronik etkileri nedeniyle ciddi ve acil bir araştırmaya gerekduyulmaktadır. Bu çevre ve sağlık problemlerinine yol açan farmasötik mikrokirleticileriatıksulardan gidermek için klasik arıtma yöntemleri yetersiz olması sebebiyleileri arıtma yöntemlerine ihtiyac duyulmaktadır. Özellikle elektrokimyasalprosesler bu tür mikrokirleticileri arıtmak için oldukça başarılı yöntemlerolarak dikkat çekmektedir. Bu çalışmada, Imatinib (IMT) adlı etken maddeninelektro-oksidasyon yöntemi ile arıtılması çalışılmıştır. Imatinib etkenmaddesinin arıtılması için kimyasal-elektrokimyasal stabiliteye sahip Ti/RuO2elektrotu kullanılmıştır. Optimum çalışma şartlarının belirlenmesi amacıylayüzey yanıt metodu (YYM) kullanılarak proses optimizasyonu yapılmıştır., The pharmaceuticals which are found in the wastewatertreatment effluents of the companies that produce cancer drug have become aserious fear for biotic living beings as they are toxic. Although theconcentration of pharmaceuticals in surface water and wastewater are in lowlevels like µg/L and ng/L levels, because of their chronical effects they areneeded to be removed from water immediately. They are not amenable toconventional biological treatment due to their toxicity even at lowconcentrations. Therefore, powerful oxidation methods have to be researched toremove them from waters, thus avoiding their potential adverse health effectson humans and animals. Especially electrochemical processes to purify suchmicro pollutants have attracted attention as very successful methods. In thisstudy, electro-oxidation of Imatinib (IMT) has been studied. Ti/RuO2electrode which has chemical and elevtrochenical stability has been used. Inorder to determine their operation conditions, process optimization has beendone by using Response Surface Method (RSM).

In this study we focus on the stability of dynamic logistic equation which is used in single species population dynamics. Here we have introduced a quadratic Lyapunov function for generalized dynamic logistic equation on time scales. By using proposed Lyapunov function, asymptotic stability conditions for the equilibrium solution of dynamic logistic equation have been investigated.