Dört bacaklı robotlar için önizlemeli kontrol ile sıfır moment noktası tabanlı yürüme yörüngesi sentezi

Bacakları üzerinde hareket eden robotların engel aşma konusunda önemli avantajları söz konusudur. Özellikle dört bacaklı robotların değişken arazi yapıları üzerinde birçok uygulamaları düşünülmektedir. Bu çalışmada, dört bacaklı bir robotun düz zemin üzerinde hızlı yol almasına yönelik tırıs türü ilerleme üzerinde durulmaktadır. Sıfır Moment Noktası (SMN) karalılık kriterine ve Doğrusal Ters Sarkaç Modeli’ne (DTSM) dayalı bir yürüme referansı sentez yöntemi sunulmaktadır. Tırıs ilerleme için bir SMN referans yörüngesi önerilmiş, bu yörüngeden, önizlemeli kontrol yaklaşımı ile Robot Ağırlık Merkezi (RAM) için bir referans yörünge elde edilmiştir. Oluşturulan ağırlık merkezi yörüngesi ters kinematik yöntemi ile bacak eklemlerinin konum referanslarının hesaplanmasında kullanılmıştır. Önerilen referans sentezi yöntemi, 16 serbestlik dereceli bir robot modeli ile üç boyutlu ve tam dinamikli bir simülasyon ortamında denenmiştir. Simülasyon sonuçları sunulan yaklaşımın başarılı olduğunu göstermektedir

Estimation of Censored Regression Model in the Case of Non-Normal Error

WOS: 000437057300017For the censored regression model, it is well-known that while classical least squares estimation yields biased and nonconsistent estimator, maximum likelihood estimator (MLE) is consistent and efficient. Tobit estimator (Tobit model) based on MLE of normal error distribution is commonly-used estimation method for estimating censored regression in econometric literature. However, while the Tobit estimator works well for normal error distribution, its estimates may be inefficient in the case of non-normal errors. To solve this problem, different error distributions for the censored regression model have been proposed and tested in the literature. In this study, we consider the censored regression model based on the generalized logistic distribution. Generalized logistic distribution is very flexible distribution and approximates normal distribution for the special parameter cases. The considered estimator for the censored regression is evaluated by means of a simulation study designed in different combination of various error distributions and sample sizes. The results of the simulation show that the estimator of the censored regression model based on the generalized logistic distribution provides good performance for different error distributions and it is particularly good for small sample sizes. Moreover, when it is compared to classical Tobit estimator, efficiency loss of the considered estimator is very small for normal error distribution.Anadolu University Scientific Research Projects Commission [1610F661, 1705F419]This study was supported by Anadolu University Scientific Research Projects Commission under the grant no: 1610F661 and also 1705F419

The analysi·s of the vali·di·ty of touri·sm-ori·ented growth hypothesi·s: The case of Turkey

Sosyal Bilimler Enstitüsü, İktisat Ana Bilim DalıTurizm bir ülkenin ekonomik, sosyal ve kültürel alanlarda getiri elde etmesini sağlayan en önemli hizmet sektörlerinden biri olarak kabul edilmektedir. Bu çalışmada, geniş bir turizm potansiyeline sahip olan Türkiye'nin turizm sektörünün ülke ekonomisindeki yeri ve önemi değerlendirilmiştir. Turizm endüstrisi Türkiye'nin önemli büyüme kaynaklarından biri olma özelliğini korumaktadır. Bu nedenle turizm potansiyeli bulunan gelişmiş ve gelişmekte olan ülkeler özellikle uluslararası turizm faaliyetlerine ağırlık vererek, hem ekonomik gelişmelerini hızlandırmak hem de geliri tabana yaymak suretiyle ülkedeki refah düzeyini yükseltmeyi amaçlamaktadırlar. Bu çalışmada 1963-2018 dönemine ilişkin Türkiye'de turizm ve ekonomik büyüme arasındaki kısa ve uzun dönemli ilişkiler eşbütünleşme ve nedensellik yöntemi ile analiz edilmiştir. Kısa dönemde iki değişken arasında bir ilişki bulunmazken, uzun dönemde turizm ekonomik büyümenin önemli bir nedenidir sonucuna ulaşılmaktadır. Elde edilen istatistikler iki değişken arasında çift yönlü bir nedenselliğin olduğu hipotezini doğrulamaktadır. Tüm bu bulgular turizm endüstrisinin Türkiye'nin önemli büyüme kaynaklarından biri olduğunu vurgulamaktadır.Tourism, recognized as one of the most important service sectors that enable countries to earn gains in economic, social and cultural fields. In this study, the place and the importance of Turkey's tourism sector in Turkish economy with a great tourism potential are evaluated. Tourism industry continues to be one of Turkey's most important sources of growth. Therefore the developed and developing countries with a tourism potential, aim to raise the level of country's welfare by accelerating the economic development, as well as by extending revenue to the base, by especially emphasising on international tourism activities. In this study,for the period of 1963-2018, shortand long-term relationships between economic growth and tourism, have been analyzed by the method of cointegration and causality. Despite there is not any relationship between two variables for the short term; the findings indicate that tourism is an important cause of economic growth for the long term. Obtained statistics support the hypothesis that there is a bidirectional (reversible) causality between the two variables. All these findings emphasize that the tourism industry is one of the most importantsources of growth in Turkey

A Study on Estimation of Wind Speed Distribution by Using the Modified Weibull Distribution

The knowledge of the probability density function of wind speed is key information for the determination of wind energy potential of the specified region. In the literature, the Weibull distribution is a widely-used and accepted distribution to express the probability density function of wind speed data. However, the Weibull distribution does not exhibit a good fitting for all wind speed data measured at different geographical locations throughout the world. Thus, in this study, it is proposed that a better fitting of wind speed data and a better estimating wind power density are possible with the new modified Weibull distribution (MWD). We also compare the performance of the MWD relative to the Weibull distribution by using wind speed data measured in different regions of Turkey. The results state that the MWD shows good fitting for the most of the considered wind speed data cases. Thus, the MWD can be an alternative tool for the assessment of wind energy potential.The knowledge of the probability density function of wind speed is key information for the determination of wind energy potential of the specified region. In the literature, the Weibull distribution is a widely-used and accepted distribution to express the probability density function of wind speed data. However, the Weibull distribution does not exhibit a good fitting for all wind speed data measured at different geographical locations throughout the world. Thus, in this study, it is proposed that a better fitting of wind speed data and a better estimating wind power density are possible with the new modified Weibull distribution (MWD). We also compare the performance of the MWD relative to the Weibull distribution by using wind speed data measured in different regions of Turkey. The results state that the MWD shows good fitting for the most of the considered wind speed data cases. Thus, the MWD can be an alternative tool for the assessment of wind energy potential

Etik, Dönüşümcü, Paternalist, Spiritüel ve Öğretimsel Liderlik Stillerinin Karşılaştırılması

In this study, it is aimed to compare the ethical, transformational, paternalistic, spiritual, and instructional leadership styles of school principals. For this purpose, the research has been carried out according to the survey model. 586 teachers from Istanbul province participated in the study. A high level of a positive correlation has been found between the leadership styles of school administrators perceived by the teachers. Teachers most perceived ethical leadership style and least perceived paternalist leadership style of school administrators. While teachers' perceptions of instructional, transformational, ethical, and spiritual leadership styles differ significantly according to their gender; It does not differ significantly according to their educational status. It has been determined that the instructional, transformational, ethical, paternalist, and spiritual leadership styles of school administrators differ significantly according to the type, grade, and age variables. The instructional, transformational, paternalist and spiritual leadership styles of school principals do not differ significantly according to the seniority variable; however, it has been determined that the ethical leadership style of school administrators differed significantly according to the seniority variable. It has been determined that instructional, transformational, ethical, paternalist, and spiritual leadership styles of school administrators differ significantly; according to the type of schools, grade, and age variables.Bu araştırmada okul müdürlerinin etik, dönüşümcü, babacan/paternalist, ruhsal/spiritüel ve öğretimsel liderlik stillerinin karşılaştırılması amaçlanmıştır. Bu amaç doğrultusunda araştırma betimsel tarama desenine göre gerçekleştirilmiştir. Araştırmaya İstanbul ilinden 586 öğretmen katılmıştır. Okul müdürlerinin öğretmenler tarafından algılanan liderlik stilleri arasında pozitif yönde yüksek düzeyde anlamlı ilişki tespit edilirken; öğretmenler okul müdürlerinin en fazla etik liderlik stilini en az ise paternalist liderlik stilini sergilediğini düşünmektedir. Öğretmenlerin öğretimsel, dönüşümcü, etik ve ruhsal liderlik stilleri algıları cinsiyetlerine göre anlam farklılık gösterirken; eğitim durumlarına göre anlamlı farklılık göstermemektedir. Öğretmenlerin görev yaptıkları okul/kurum türüne/kademesine ve yaşlarına göre okul müdürlerinin öğretimsel, dönüşümcü, etik, paternalist ve ruhsal liderlik stilleri anlamlı farklılık gösterdiği tespit edilmiştir. Okul müdürlerinin öğretimsel, dönüşümcü, paternalist ve ruhsal liderlik stilleri öğretmenlerin kıdemlerine göre anlamlı farklılık göstermediği; ancak okul müdürlerinin etik liderlik stili öğretmenlerin kıdemlerine göre anlamlı farklılık gösterdiği belirlenmiştir

MEASURING THE EFFECT OF SOCIAL MEDIA USE ON HOLIDAY PURCHASE AND HOLIDAY MOTIVATION ON REVISITS

Apart from working hours and personal needs of individuals, they need to spend time for fun, listening, many activities that bring together their interests and personal preferences. One of the most well-known of these needs is tourism activities. Behaviors that affect participation in leisure time tourism activities is an issue that needs to be examined. In this context, the aim of the research is to examine the holiday buying and holiday motivation, revisit behaviors of individuals using social media. The population of the research consists of individuals using social media in Eskişehir. With the convenience sampling method, 409 people from state universities throughout Eskişehir were reached in the form of face-to-face and online forms. In order to collect data, the Effect of Social Media on Tourists' Holiday Decisions developed by (Eşitti & Işık 2015), Purchasing Intent Scale developed by (Pavlou & Gefen, 2004), Tourism Motivation Scale developed by (Carrol & Alexandris, 1997) and finally (Altunışık) v.d, 2001) were used to use the Revisit Intention Scales. In the analysis of the data, SPSS 26 program was used and analyzes were made. In these analyzes, a positive and significant relationship was determined between the individuals' social media use, holiday purchase and holiday motivation, and revisit levels. As a result, it has been concluded that the high level of participation of individuals using social media in purchasing a holiday, together with their socio-economic status, positively affects their holiday motivations and revisit attitudes. In addition, the information obtained can be useful for tourism businesses, travel agencies and businesses serving in the recreation industry

Okul Kültürünün Okul Etkililiğine ve Performansa Etkisi: Öğretmen ve Yönetici Görüşlerinin Karşılaştırılması

The aim of this study is to compare the effect of school culture on school effectiveness and performance according to the opinions of teachers and administrators. The sample of the study consists of 3468 teachers and 425 administrators working in Istanbul in the 2019-2020 academic year. Predictive survey model was used as the research model. The data were collected with the help of "School Culture Scale", "School Effectiveness Index" and "Performance Scale". The data were analyzed by correlation and regression analysis. While the task culture and support culture positively affected the performance of the teachers, respectively; bureaucratic culture and success culture do not affect teachers' performance. The support culture, task culture and success culture affect the school effectiveness the most, respectively. In addition, teachers' performance affects school effectiveness positively. While the support culture and task culture positively affect the performances of the managers, success culture and bureaucratic culture do not affect the performances of the administrators. While the support culture and bureaucratic culture affect school effectiveness the most, success and task culture do not. In addition, the performance of administrators has a positive effect on school effectiveness.Bu çalışmanın amacı, okul kültürünün okul etkililiğine ve performansa olan etkisini öğretmen ve yönetici görüşlerine göre karşılaştırmaktır. Araştırmanın örneklemini 2019-2020 eğitim-öğretim yılında İstanbul İlinde görev yapan 3468 öğretmen ve 425 yönetici oluşturmaktadır. Araştırma modeli olarak yordayıcı tarama modeli kullanılmıştır. Veriler, “Okul Kültürü Ölçeği’’, “Okul Etkinliği Endeksi” ve ‘‘Performans Ölçeği’’ yardımıyla toplanmıştır. Veriler korelâsyon ve regresyon analizleri ile çözümlenmiştir. Bulgulara öğretmenlerin performansını sırayla en fazla görev kültürü ve destek kültürü olumlu yönde etkilerken; bürokratik kültür ve başarı kültürü öğretmenlerin performanslarını etkilememektedir. Okul etkililiğini sırasıyla en fazla destek kültürü, görev kültürü ve başarı kültürü etkilemektedir. Ayrıca öğretmenlerin performansı da okul etkililiğini olumlu yönde etkilemektedir. Yöneticilerin performanslarını sırayla en fazla destek kültürü ve görev kültürü olumlu yönde etkilerken, başarı kültürü ve bürokratik kültür yöneticilerin performanslarını etkilememektedir. Okul etkililiğini sırasıyla en fazla destek kültürü ve bürokratik kültür etkilerken, başarı ve görev kültürü etkilememektedir. Ayrıca yöneticilerin performansı da okul etkililiğini olumlu yönde etkilemektedir

A bibliometric review of architectural studies in the field of tourism

Architecture is an essential field of study that affects many aspects of tourism, such as accommodation, infrastructure, and recreation. In particular, it is an indispensable discipline for tourism as it is an attractive element that affects tourists’ perception of space and environment. The strong influence of architecture in tourism has also been reflected in academia over the past 25 years, and the impact and importance of architecture in international tourism destinations have been discussed in many countries. In light of the importance of tourism architecture and the recent academic developments, this study conducted a bibliometric analysis to provide an overview of the development trends in architectural studies within tourism. Between 2000 and March 2024, only articles written in English were included in the study, and the Web of Science Core Collection database was used to obtain data. The VOSviewer package was used to analyze the data of 136 articles. As a result of the analysis, it was found that there was an irregularity in the frequency of studies in the related field over the years. It was also found that studies on architecture in tourism are concentrated in different research fields such as ecology, architecture, environmental sciences, and rural studies. The study concludes with evaluations of the related field and suggestions for future research