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The current study examined the effect of a cooperative (vs. a non-cooperative solitary) mobile game on social behaviors and positive affect during gameplay in middle childhood. In a within-participants experimental design, groups of fifth graders (ages from 10 to 12) played in counterbalanced order cooperative and solitary versions of a cooking game developed for tablets. Our findings showed that children who played the cooperative (vs. solitary) mobile game engaged in more positive and neutral conversations during gameplay. They also sought and received more help from peers and displayed greater positive affect during cooperative (vs. solitary) gaming. Finally, they preferred the cooperative mobile game to the otherwise identical solitary game after playing both games. Overall, these findings provide the first experimental evidence of the social and affective benefits of cooperative mobile gaming in middle childhood.

In this study, optimal power management strategy to make optimal operation of the alternative sources has been considered to meet the load demand of heating, ventilations and air conditioning (HVAC) units for public institutions, hospitals, schools, etc. A hybrid power system consisting of wind türbine (WT), photovoltaics (PV) and battery has been proposed. The system is modelled to be used in an optimal demand response application. Moreover, the grid has been added to the hybrid power system due to the intermittent generation characteristics of alternative power sources. The objectives defined by the optimization problem are the operation of the alternative power sources at maximum rate and primarily meeting the HVAC load demand by the relevant sources. The resulting mixed-integer linear programming model is tested in GAMS v.24.1.3 platform using the solver CPLEX v.12., Bu çalışmada, kamu kuruluşları, hastane, okul vb. gibi kurumların iklimlendirme cihazlarının yük talebinin karşılanmasında alternatif enerji kaynaklarından optimal olarak yararlanma stratejisi ele alınmıştır. İklimlendirme yüklerinin karşılanmasında rüzgar türbini (RT), güneş pili (GP) ve batarya (Bat) ile teşkil edilen hibrit güç sistemi önerilmiştir. Hibrit güç sistemi optimal talep cevabı uygulamasında kullanılmasına imkan verecek şekilde modellenmiştir. Ayrıca, hibrit kaynakların kesintili üretim karakteristikleri gereği hibrit güç sistemine şebeke gücü de ilave edilmiştir. Optimizasyon probleminde alternatif enerji kaynaklarının maksimum kapasitede kullanımı ve ilgili kaynakların öncelikli olarak iklimlendirme yüklerinin talebine cevap verecek şekilde kullanımı amaç olarak belirlenmiştir. Elde edilen karışık tamsayı lineer programlama modeli GAMS v.24.1.3 ortamında CPLEX v.12 çözücüsü ile test edilmiştir. Kış ve yaz koşulları dikkate alınarak optimal işletim modelinin benzetim çalışmaları yapılmıştır ve ilgili sonuçlar sunulmuştur.

In this paper, household electricity load profile (LP) clustering problem is addressed. LP clustering analysis has been utilized as predicted end-user LPs for demand or supply management strategies to maintain the stability of the power systems. The consumption dynamics of the LPs are formed by the combinations of technical and social factors. Hence, discovering the dynamic patterns of the LPs has been a challenging problem. For this problem, we have offered successive applications of Sugeno fuzzy-logic (SFL) and self-organizing map neural network (SOMNN) techniques. Firstly, the data sets of the LPs are clustered by fuzzy logic approach by the reference models which are generated with the common family-types per persons. Then, considering the extra input of the weighted occupancy profiles, SOMNN is performed to improve the clustering result according to the dataset. The proposed strategy has been simulated by MATLAB® and the related results are presented.

This paper aims to present a practical technique for the synthesis of proportional controllers for continuous time control systems. This technique depends on the generalization of the Nyquist stability criterion and promises soft computing of the crossing direction of the diagram where the plot crosses the real axis on the complex plane.

This paper proposes a theoretical and practical approach for determining the stabilizing gain intervals for two-input, two-output (TITO) systems with a constant diagonal controller. Our main contribution is to present an algorithm which is more practical than the stabilizing methods that depend on the Nyquist stability criterion. Numerical examples illustrate the effectiveness of the proposed algorithm for TITO systems with reducible or irreducible characteristic equations.

Renewable energy management and conditioning system for distributed generation (DG) has been a promising research topic due to the advantages on efficiency, energy quality and environmental effects. Recently, it has been emerged as an efficient tool to meet the demand by residential loads. There have been presented numerous studies about the integration of DG units with hybrid configurations of energy storage systems and renewable sources to supply the domestic loads via single phase inverters. In this paper, a novel operation strategy of a single phase inverter for DG systems has been proposed. The essential point of the proposed strategy has been based on to generate a rectified sinusoidal waveform on DC bus contrary to the conventional methods. The proposed operation strategy has been tested on Matlab®/Simulink environment and then it has been verified by an experimental study.

Despite the fact that, a great number of utility models powered by renewable energy sources have been penetrated into the grid or off grid power sources, it is already an important problem to meet the demanded power by those sources in a sustainable way. Therefore, the research on power management structure for hybrid power system (HPS) have been focused by the researchers. In the view of the related studies, we proposed a novel approach to design power management scheme that is applicable to any such HPS. This approach is based on choosing the DC bus voltage in the power conditioning system as rectified sinusoidal wave form so as to use such an inverter which provides to switch at 50 Hz and synthesizing PI type controllers to regulate the voltage on the bus. By the merits of low switching inverter and controller design, we claim that this novel approach not only gives rise to recovery in the power quality, as well as, it does not need necessitate to design filter at the output of the inverter.

In recent years, automobile industry focuses on the reducing the imperfections of hybrid electric vehicles (HEVs), such as higher cost, added weight of batteries, limited range, recharging facilities and emission rates. In the view of the related studies, we can infer that fuel cell (FC)-Battery hybrid configuration is a viable alternative solution. Such that, FCs are eco-friendly and proper for long ranged drives, on the other hand batteries have fast response for varying power demands. Moreover, FC-Battery hybrid electric vehicle (FCBHEV) proposes solutions for the imperfections. So, we deal with optimal sizing of FCBHEV and propose a methodology for the optimization of HEV components using the multi-objective approach considering the minimization of operating cost, weight and volume simultaneously. To optimize the sizing of HEV components, the mixed integer linear programming (MILP) model is tested in GAMS v.24.1.3 using the solver CPLEX v.12 and optimization processes are performed for different range of drive cycles and the results are discussed to reveal the effectiveness of the approach.

There are several services such as peak load reduction and frequency regulation that can be provided by exploiting the thermostatically-controllable appliances (TCAs) demand response (DR) potential. To stimulate the adoption of DR strategies, preserving the end-user comfort level is a crucial issue. In this regard, as a novel contribution to the existing literature, this study proposes a DR strategy for residential heating, ventilation and air conditioning (HVAC) units aiming to minimize average end-user comfort violation, while satisfying the requirements of the load serving entity. The proposed approach manipulates the temperature set-point of HVAC thermostats of the enrolled end-users. Besides, a spatio-temporal to obtain weather forecasts is developed.

In this chapter, the basic principles of optimization and the mathematical formulation of the optimization problem have been provided. Besides, the categorization of the optimization problems has been presented in terms of the number of constraints, the structure of the variables, and linearity of the formulation elements. Considering the most familiar type of optimization problem, linear optimization approach has been examined in details. Then, some remarkable optimization techniques under the classification of unconstrained and constrained techniques have been investigated. Moreover, as regarding the increasing trend in the utilization of intelligent constrained optimization methods for the implementation and operational problems of renewable energy technologies, the literature have been reviewed.

Bu tez çalışması Halit Ziya'nın II. Meşrutiyet sonrası Darülfünun'da Batı Edebiyatı Tarihi derslerine bir giriş olarak verdiği Yunan Edebiyatı Tarihi dersi sonucunda öğrenci notlarının basılmasıyla oluşan metin üzerine yapılan bir incelemeden oluşmaktadır. Bu çalışmanın amacı incelenen ders notunun Tanzimat'la başlayan Türk edebiyatında Yunan antikitesi mirasını tanıma ve benimseme sürecindeki yerini belirtmek ve bu sürecin bir parçası olarak Halit Ziya'nın eğitimci ve edebiyat tarihçisi kimliğini göstermeye çalışmaktır. Anahtar Kelimeler: Halit Ziya, Darülfünun, ders notu, antikite, Yunan Edebiyatı Tarihi This thesis study consists of an examination of the text formed by printed versions of the lecture notes of Halit Ziya's Greek Literature History courses given as an introduction to Western Literature History lessons after the Constitutional Period in Ottoman university, Dar-el Funun. This study aims to emphasize the importance of the notes in adoption and acknowledgement process of Greek antiquity heritage that becomes visible in Turkish Literature after Tanzimat (Reform) Era and, as a part of this process, tries to show Halit Ziya's academician and literature historian identity. Key Words: Halit Ziya, Dar-el Funun, lecture note, antiquity, Greek Literature History 137

The 2 gain control problem for disturbance attenuation in Linear Parameter Varying (LPV) Systems with saturating actuators has been addressed where the systems handled in the study are subjected to 2 disturbances. The aim in the presented method is to express saturating actuator analytically with a convex hull of some linear feedback. This point of view allows us to construct 2 control problem via Linear Matrix Inequalities (LMIs). Nested ellipsoids have been used to measure the stability and disturbance rejection capabilities of the control system. At the end, the proposed controller scheme has been simulated on a single-track vehicle dynamics with some linear time-varying parameters and a wind disturbance.

Depending on growing concerns on energy crises and environmental issues, fuel cell (FC) powered electrical vehicles are favored for possible substitute to conventional internal combustion engine (ICE) based vehicular systems. However, the typical power profile of an automobile motor consisting of transients is not suitable for the use of a sole FC system for vehicle propulsion. This shortcoming could be partly overcome by hybridization. Two potential benefits of combining an FC system with an energy storage unit, ultra-capacitor (UC) has been presented in this study. Firstly, the durability of the FC system could be improved because the additional energy source can fulfill the transient power demand fluctuations. Secondly, the ability of the energy storage source to recover braking energy enhances the fuel economy greatly. An important aspect in designing a hybrid power structure is to find a suitable control strategy that can manage the active power sharing and take advantage of the inherent scalability and robustness benefits of the hybrid system. An integrated procedure for mathematical modeling and power control strategy design for an FC/UC hybrid vehicle is presented in this paper. A fuzzy logic supervisory controller based power management strategy that secures the power balance in hybrid structure, enhances the FC performance and minimizes the power losses is proposed. The main contribution of this paper apart from the previous studies of the authors is the modeling of the complete FC power system with air supply compressor and the integration of the control of the FC system internal dynamics (especially the oxygen excess ratio) into the overall supervisory control structure to maximize the efficiency and durability. To demonstrate the effectiveness of the proposed power management scheme, simulation studies were performed using MATLAB (R), Simulink (R) and SimPowerSystems (R) environments by integrating the detailed mathematical and electrical models of the hybrid vehicular system. Crown Copyright (C) 2009 Published by Elsevier Ltd on behalf of Professor T. Nejat Veziroglu. All rights reserved.

This paper addresses the L2 gain control problem for disturbance attenuation in Linear Parameter Varying (LPV) Systems having saturating actuators when the system is subjected to L2 disturbances. In the presented method, saturating actuator is expressed analytically with a convex hull of some linear feedback which let us construct L2 control problem via Linear Matrix Inequalities (LMIs) which are obtained by some ellipsoids. It is shown that the stability and disturbance rejection capabilities of the control system are all measured by means of these nested ellipsoids where the inner ellipsoid covers the initial conditions for states whereas the outer ellipsoid designates the L2 gain of the system. It is shown that the performance of the controller is highly related by the topology of these ellipsoids. Finally, the efficiency of the proposed method is successfully demonstrated through simulation studies on a single-track vehicle dynamics having some linear time-varying parameters.

In this paper we present a novel controller for Shape Memory Alloy (SMA) actuated robotic systems. The new controller, called BAC (B-spline based Adaptive Control), is based on a hybrid combination of gain scheduling, B-spline approximation, variable structure control and integral control. The proposed controller shows excellent positioning accuracy and speed throughout the full range of motion of a SMA actuated robotic system in large-scale applications. To demonstrate the validity of BAC, a novel anthropomorphic SMA Actuated forearm/wrist mechanism is utilized in real-time PC based control experiments. BAC is experimentally compared to PID and integral variable structure controllers and it is shown that its performance is superior.

ÇOKLU HAYAT TABLOLARI VE TÜRKİYE'YE YÖNELİK BİR UYGULAMA Yavuz Eren Ataman Hacettepe Üniversitesi, istatistik Bölümü, istatistik Anabilim Dalı Aktüerya Bilim Uzmanlığı Programı ÖZ Sigorta kapsamına alınan kişi sayısı, sigortacılığın hayat branşında önemli bir sınıflandırma kriteridir. Tasarrufa veya ölüme bağlı hayat sigortalarında, poliçe primleri hesaplanırken, poliçe kapsamına alınan kişi sayısına uygun olan çoklu hayat fonksiyonları kullanılmalıdır. Hazırlanmış olan bilim uzmanlığı tezinin amacı, Türkiye'de hayat sigortası sektöründe kullanılan, cinsiyet bazında ayrılmış hayat tablolarını kullanarak, çoklu hayat tabloları oluşturmaktır. Genel bilgiler başlığı altında, öncelikle tekli hayat kavramı ve bu kavrama ait fonksiyonlar incelenmiştir. Daha sonra, çoklu hayat kavramı ve bu kavramı içeren durumlara değinilmiştir. Uygulama kısmında ise, Türkiye'ye yönelik çoklu hayat tabloları oluşturulmuştur. Anahtar Keiimelsr: Hayat sigortası, hayat tabloları, mortalite, tekli hayat fonksiyonları, çoklu hayat fonksiyonları, birleşik hayat durumu, son hayatta kalan durumu, çoklu hayat tabloları. Danışman: Prof. Dr. Gülsüm HOCAOĞLU, Hacettepe Üniversitesi, İstatistik Bölümü MULTIPLE LIFE TABLES AMD AN APPLICATION FOR TURKEY. Yavuz Er@n Ataman Hacettepe University, Department of Statistics, Actuarial Science Program ABSTRACT In life insurance, an important basis for classification is the number of lives covered in. According to the number of lives covered in contracts, appropriate multiple life functions should be used in calculation of life insurance or life annuity premiums. The aim of this master thesis is to construct multiple life tables based on female and male life tables used in life insurance sector in Turkey. In the general information section of this study, firstly, single life concept and single life functions are covered. Then, multiple life theory and its statuses are examined. Finally, in the application part, multiple life tables for Turkey are constructed. Keywords: Life insurance, life tables, mortality, single life functions, multiple life functions, joint-life status, the last-survivor status, multiple life tables. Advisor: Prof. Dr. Gülsüm HOCAO?LU, Hacettepe University, Department of Statistics 11 98

Bu çalışmada bilişim teknolojileri öğretmen adaylararının Facebook kullanımlarını ve Facebook?un mesleki gelişimlerindeki yeri konusundaki görüşlerini değerlendirmek için açıklayıcı karma araştırma yöntemi uygulanmıştır. Nicel kısımda, Facebook kullanım anketi yoluyla, Türkiye?deki üç temsili devlet üniversitesinin Bilgisayar ve Öğretim Teknolojileri Eğitimi Bölümlerindeki toplam 338 lisans öğrencisinden veriler toplanmıştır. Anket sonuçları öğretmen adaylarının Facebook?u beğendiklerini ve Facebook?dan yararlandıklarını göstermiştir. Ancak, daha ayrıntılı verilere ulaşmak için, nicel veri analizi sonuçları, kasıtlı seçilmiş dört öğretmen adayı ile yapılacak olan planlanmış bir görüşmenin hazırlanmasında kullanılmıştır. Görüşmeler sonucu toplanan verilerin anlamlı gruplandırılması için kodlama yapılarak veriler içerik analizine tabi tutulmuştur. Bu açıklayıcı araştırma sonuçlarına göre Facebook?un özellikle iletişim, paylaşım ve sosyalleşmedeki kapasitesi, Facebook?un bir mesleki gelişim aracı olarak kullanılmasında önemli bulunmuştur., In this study, an explanatory mixed method design was employed to evaluate preservice information technology teachers‟ Facebook usage and their perspectives about Facebook as a professional development tool. In quantitative phase, data were collected through a Facebook usage survey on a total number of 338 undergraduate Computer Education and Instructional Technology CEIT students from three representative state universities in Turkey. Survey results indicated that preservice teachers favored and utilized Facebook. To find out more in-depth data, the results of quantitative data analysis were used to develop a structured interview to be done with four preservice teachers who were selected purposefully. The data collected from the interviews were subjected to content analysis where coding was conducted to create meaningful organization of the data. According the results of this explanatory study especially communication, sharing and socializing capacity of Facebook were found important in terms of using Facebook as a professional development tool