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Öğe PID controller design for controlling integrating processes with dead time using generalized stability boundary locus(IFAC Secretariat, 2018) Atiç, Serdal; Çökmez, Erdal; Peker, Fuat; Kaya, İbrahimThis paper proposes a method so that all PID controller tuning parameters, which are satisfying stability of any integrating time delay processes, can be calculated by forming the stability boundary loci. Processes having a higher order transfer function must first be modeled by an integrating plus first order plus dead time (IFOPDT) transfer function in order to apply the method. Later, IFOPDT process transfer function and the controller transfer function are converted to normalized forms to obtain the stability boundary locus in (KKcT, KKc(T2 / Ti)), (KKcT, KKcTd) and (KKc(T2/Ti), KKcTd) planes for PID controller design. PID controller parameter values achieving stability of the control system can be determined by the obtained stability boundary loci. The advantage of the method given in this study compared with previous studies in this subject is to remove the need of re-plotting the stability boundary locus as the process transfer function changes. That is, the approach results in somehow generalized stability boundary loci for integrating plus time delay processes under a PID controller. Application of the method has been clarified with examples.Öğe An analysis of sport managers' work stress levels in various variables(Horizon Research Publishing, 2018-12) Kılınç, Zühal; Dinçer, NevzatThis paper was conducted to measure the psychological and psychosomatic symptoms related with the sport managers’ work stress in public sector and federations. In this research, total 185 sport managers including 31 sport managers from the Central Organization of Sport General Directorate, 113 sport managers from the provincial organization, 41 sport managers from the Independent Sport Federations were included. The relevant managers were applied the work stress scale developed by Houso and Rizzo (1972). According to the results of the research, as sport managers get older, the averages of work stress seem to increase. In younger sport managers, the averages of work stress were found to be lower. When the participant sport managers’ education levels improve, their work stress points fall down. In the first period of service of sport managers, the averages of work stress were high, in next years they went down over time.Öğe Performance and exhaust emissions of a DI diesel engine fueled with waste cooking oil and inedible animal tallow methyl esters(TÜBİTAK, 2011) Altun, ŞehmusThe performance and exhaust emissions of a direct injection diesel engine were experimentally investigated using 2 biodiesel fuels with promising economic perspective, one obtained from inedible animal tallow and the other from waste cooking oils. Inedible animal tallow, which is obtained from a mixture of slaughtered cattle and sheep fats collected from a local slaughterhouse during meat preparation process, was transesterified using methyl alcohol and an alkaline catalyst to produce the inedible animal tallow methyl ester. Biodiesel from waste cooking oil was produced from waste cooking oils and methyl alcohol via a transesterification reaction, and provided by a commercial biodiesel producer. In order to investigate the performance and exhaust emissions, the experiments were conducted at different engine speeds under the full load condition of the engine. The experimental results showed, compared with diesel fuel, that the biodiesel fuels resulted in a reduction in brake torque and in an increase in brake specific fuel consumption. Although both biodiesels caused reductions in carbon monoxide (CO), the NOx emissions were higher for waste cooking oil biodiesel and lower for inedible animal tallow biodiesel as compared to diesel fuel.Öğe Doküman dili tanıma için yeni bir öznitelik çıkarım yaklaşımı: İkili desenler(Gazi Üniversitesi, 2016-12-14) Kaya, Yılmaz; Ertuğrul, Ömer FarukDoğal dil işlemenin önemli alt konularından biri olan dil tanıma (DT), bir dokümanın içeriğine göre yazıldığı dili belirleme işlemidir. Bu çalışmada, karakterlerin UTF-8 değerlerini birbirleri ile karşılaştırmalar sonucu elde edilen ikili desenler kullanarak yeni bir dil tanıma yaklaşımı, bir boyutlu yerel ikili örüntüler (1B-YİÖ) önerilmiştir. Önerilen yöntem farklı sayıda dillerden oluşan metinler içeren dört veri kümesi ile test edilmiştir. 1B-YİÖ ile dokümanlardan elde edilen öznitelikler kullanılarak farklı makine öğrenmesi yöntemleri ile sınıflandırma işlemi gerçekleştirilmiştir. Dört veri kümesi için sınıflandırma başarıları sırası ile %86.20, %92.75, %100 ve %89.77 olarak gözlenmiştir. Elde edilen sonuçlara göre önerilen öznitelik çıkarım yönteminin dil tanıma için önemli örüntüler sağladığı görülmüştür.Öğe Karyotypes of the Mole Rats, genus Nannospalax (Palmer, 1903) (Spalacidae: Rodentia) populations in eastern Anatolia, Turkey(Research Affairs of Ferdowsi University of Mashhad, 2012) Coşkun, Yüksel; Kaya, Alaettin; Ulutürk, Servet; Yürümez, Gökhan; Moradi, MohammadThe Spalacidae are Southeast European and East Mediterranean blind rodents, highly adapted for life underground. Their taxonomy needs a modern revision including chromosomal data as well as morphology. Mole rats of the family Spalacidae range over Turkey and approximately 30 karyotypes of Nannospalax complex inhabit. The diploid number of chromosome of Nannospalax ranges from 36 to 62. Also, fundamental number of chromosomal arms, NF values vary from 66 to 92 while the fundamental number of autosomal arms, NFa ranging from 62 to 88. Unfortunely, karyological studies of the Nannospalax populations on the territory of Turkey on the whole are far from being satisfactory. Karyological studies of this group may yield further chromosomal forms in Turkey, which has a wide range of climatic and biotic conditions and the boundaries of the distribution region of the known species might be determined. In this study, chromosomal forms of Nannospalax in East Anatolia (Erzurum, Kars and Ağrı province) were investigated. The materials of 16 specimens of Nannospalax were collected at 8 different localities in the region. Preparations of mitotic chromosomes were obtained from bone marrows by means of the general air-drying technique. Skins and skulls of specimens have been deposited at the Dicle University, Science Faculty Biology Department. We have identified two chromosomal forms of Nannospalax in East Anatolia of which have diploid chromosome numbers (2n) are 2n = 48 and 2n = 50Öğe Multivariate pade approximations for solving nonlinear diffusion equations(Walter de Gruyter, 2015-11-24) Turut, VeyisIn this paper, multivariate Pade approximation is applied to power series solutions of nonlinear diffusion equations. As it is seen from tables, multivariate Pade approximation (MPA) gives reliable solutions and numerical results.Öğe Associations between online addiction attachment style, emotion regulation depression and anxiety in general population testing the proposed diagnostic criteria for internet addiction(Kure İletisim Grubu A.Ş., 2019) Ceyhan, Ebubekir; Boysan, Murat; Kadak, Muhammed TayyipThe focus of this study was twofold. The first aim of the study was to investigate psychometric properties of the Turkish version of the Chen Internet Addiction Scale (CIAS). Second, we explored the relations between Internet Addiction, Attachment Style Emotion Regulation, Depression and Anxiety among college students. A total of 754 college students participated in the study. The CIAS, Young Internet Addiction Test (YIAT), Experiences in Close Relationship-Revised (ECR-R), Difficulties in Emotional Regulation Scale (DERS), Center for Epidemiological Studies Depression Scale (CES-D), Beck Anxiety Inventory (BAI), and WHO Disability Assessment Schedule 2.0 (WHODAS 2.0) were administered in the study. The CIAS was subjected to confirmatory factor analysis. The associations between Internet addiction, attachment styles, difficulty in emotion regulation, anxiety and depression were evaluated using one-way analysis of variance and logistic regression analysis. The signal detection analysis showed that a cut value of 64 for the CIAS, with diagnostic accuracy of 97.1% and a cut value of 40 for the YIAT, with diagnostic accuracy of 86.9% were evaluated to be best diagnostic cutoff points. Considering univariate relationships between variables of interest, fearful and preoccupied attachment were significantly associated with pathological Internet use. Logistic regression analyses demonstrated that being male, difficulties in emotional regulation, anxiety and depression statistically significantly contributed to the risk for development of Internet addiction. Internet addiction as indexed by the CIAS cutoff is a highly debilitating mental disorder.Öğe Electronic parameters of MIS Schottky diodes with DNA biopolymer interlayer(Walter de Gruyter, 2015-09-01) Güllü, Ömer; Türüt, AbdülmecitIn this work, we prepared an ideal Cu/DNA/n-InP biopolymer-inorganic Schottky sandwich device formed by coating a n-InP semiconductor wafer with a biopolymer DNA. The Cu/DNA/n-InP contact showed a good rectifying behavior. The ideality factor value of 1.08 and the barrier height (Φb) value of 0.70 eV for the Cu/DNA/n-InP device were determined from the forward ias I-V characteristics. It was seen that the Φb value of 0.70 eV obtained for the Cu/DNA/n-InP contact was significantly larger tan the value of 0.48 eV of conventional Cu/n-InP Schottky diodes. Modification of the interfacial potential barrier of Cu/n-InP iode was achieved using a thin interlayer of DNA biopolymer. This was attributed to the fact that DNA biopolymer interlayer increased the effective barrier height by influencing the space charge region of InP.Öğe HPA algoritması ile çok makinalı güç sistemi kararlı kılıcısı tasarımı(Gazi Üniversitesi, 2017-12-08) Ekinci, Serdar; Hekimoğu, BaranBu makale, parçacık sürüsü optimizasyonu (PSO) ve yapay arı kolonisine (ABC) dayalı, çok makinalı güç sisteminde güç sistemi kararlı kılıcısının (PSS) optimal tasarımı için iyimser sonuçlar bulmak için güçlü yetilere sahip HPA tekniği adında yeni bir hibrit yaklaşımı tanımlamaktadır. PSS parametrelerinin en uygun ayarlarının elde edilmesi için PSS parametrelerini seçme problemi, özdeğer tabanlı bir amaç fonksiyonu ile basit bir optimizasyon problemine çevrildi ve HPA tekniği kullanılarak çözüldü. Önerilen HPA tabanlı PSS tasarımının etkinliği özdeğer analizi, zaman domeni simülasyonları ve bazı performans indeksleri aracılığıyla farklı arızalar altındaki 3-makinalı 9-baralı güç sistemi üzerinde doğrulandı. Bu çalışmaların sonuçları, HPA algoritmasının PSS parametrelerinin ayarlanması için alternatif ve daha etkin bir iyileştirici olduğunu ve PSO ile ABC’ye oranla güç sisteminin dinamik kararlılığını büyük oranda artırdığını göstermiştir. Ayrıca hesaplama zamanı, yaklaşım hızı ve çözüm kalitesi açısından HPA algoritmasının PSO ve ABC’ye göre potansiyeli ve üstünlüğü kanıtlanmıştır.
