Nanorefrigerants are considered the most efficient heat transfer fluids for improving heat transfer properties in the refrigeration and air conditioning equipment. For the first time in this study, ...energy, exergy, and environmental evaluation (3E) analyses were performed by the addition of different nanoparticles to a low GWP refrigerant pair such as R290/R1233ZDE in a cascade refrigeration system. CNT, CuO, and, TiO2 nanoparticles were added to the refrigerant. The effect of nanoparticles on the cascade refrigeration system was analyzed using a model based on density changes. A detailed thermodynamic analysis was performed of the cascade refrigeration system at different evaporator temperatures and mass ratios. The power consumption of the compressor decreases as the evaporator temperature increases for all types of nanoparticles, resulting in an increase in COP values. The analyses showed that CuO nanoparticles had the highest performance. It has been observed that the energy and exergy efficiency increase as compressor work decreases with increasing mass ratios in all nanorefrigerants. In addition, the results indicated that all nanorefrigerants emit lower monthly CO2 emissions compared to the pure refrigerants. The nanorefrigerants play a crucial role in reducing energy consumption and promoting environmental protection compared to traditional refrigerants.
DERİN ÖĞRENME TEMELLİ OTOMATİK YARDIM MASASI SİSTEMİ Metin Yılmaz; Efnan Şora Günal
Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi,
12/2022, Letnik:
30, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Yardım masası, bir organizasyonun çalışanlarına veya müşterilerine merkezi bilgi ve destek yönetimi hizmeti sağlayan iletişim noktasıdır. Organizasyonun verimliliği açısından, yardım masasına gelen ...taleplerin doğru kategorilere ayrılarak, doğru kişilere ve zamanında yönlendirilmesi büyük önem arz etmektedir. Bu sebeple, bu çalışma kapsamında, derin öğrenmeye dayalı otomatik bir yardım sistemi önerilmiştir. Önerilen sistem, talepleri, başlıklarında yer alan cümlelere göre otomatik olarak uygun kategorilere ayırmaktadır. Bu işlem için kelime gömme (ing. word embedding) yöntemi kullanılmıştır. Metin ön işleme adımlarından sonra, üç katmanda (embedding, flatten ve dense) öğrenme gerçekleştirilerek, yardım masası taleplerinin ait olduğu kategori belirlenmektedir. Bu amaçla, kurumsal bir şirkete ait BT yardım masası talepleri kullanılmıştır. Dokuz farklı kategoride toplam 28.104 talepten oluşan veri kümesi, %60 eğitim, %20 doğrulama ve %20 test kümesine ayrılmıştır. Yapılan deneyler sonucunda %98’e ulaşan sınıflandırma doğruluğu, önerilen modelin otomatik bir yardım masası sistemi için iyi bir aday olduğunu ortaya koymuştur.
In this paper, optimization-oriented high fidelity indicated torque models which cover the whole operating regions under both steady-state and transient cycles for heavy-duty vehicles are developed. ...Two different experiments are performed and their data are merged to be utilized in the training of the models. In the first experiment, all combustion input channels are excited by quadratic chirp signals with different sweeps in their frequency profiles. Different from the first experiment, the engine speed is excited by ramp-hold signals in the second experiment. The estimations of friction, pumping and inertia torques in addition to the torque measured from the engine dynamometer are utilized in the indicated torque calculations. In order to model the calculated indicated torque, a nonlinear finite impulse response (NFIR) model with a single layer sigmoid neural network has been designed. A sensitivity analysis is performed by generating several models with different number of input regressors and neurons. Experimental results show that the majority of the models in a selected wide range of the model parameters are validated with fit accuracies higher than 90 % and 85 % on the World Harmonized Stationary Cycle (WHSC) and the World Harmonic Transient Cycle (WHTC), respectively.
VERİ ODAKLI HATA TEŞHİS SİSTEMİ GELİŞTİRİLMESİ Metin YILMAZ; Ahmet YAZICI; Eyüp ÇINAR
Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi,
12/2020, Letnik:
28, Številka:
3
Journal Article
Recenzirano
Odprti dostop
In this study, a literature review on Development of a Data-Oriented Fault Diagnosis System is presented and details of an application on a use-case is proposed with analysis and results. With an aim ...on utilizing the application with CNC machines and rolling bearings,an intelligent fleet-based monitoring system application is implemented.The implemented method ensures afleet-based monitoring system is capable of monitoring machines with same type of data and features in a manufacturing environment. The methodology is tested on four rolling bearing offline datasets. The corresponding anomaly scores of each component is calculated and presented.
Background and Study Aim. This study was conducted to determine the state of readiness of prospective physical education and sports teachers, who were studying in sports education institutions in ...Turkey.
Material and Methods. The sample of the study consisted of 552 prospective physical education and sports teachers, who were chosen by the random sampling method. To collect the data from the sample group, the “Preparedness for Teach Scale”, which consisted of 20 items and 4 subscales. The collected data were analysed for normality by using SPSS 22.0 package software. Because the data demonstrated a normal distribution, the “Independent Samples t-tests” and “One-way ANOVA tests” were conducted. To determine the level of relationship between dependent variables, “Pearson Correlation Analysis” was conducted.
Results. In the gender variable of the sample group, statistically significant differences were observed in the subscales of “Designing the instructional process” and “Understanding the learner”. In the grade variable, significant differences were determined in the subscales of “Forming and effective learning atmosphere”, “Designing the instructional process” and “Techno-pedagogical competence”. In the variable of the department of education, significant differences were determined in all the subscales. Because of the correlation analysis, it was observed that there were positive and strong correlations between the subscales of “Forming an effective learning atmosphere” and “Designing the instructional process” (r= 0.807; p<0.05).
Conclusions. For teachers to become more confident in themselves and develop their competencies more positively, it will be beneficial to enlarge professional standards and teaching framework. Within this scope, considering the results obtained from the study, it will be beneficial to create positive classroom environments and to ensure that prospective teachers benefit from teachers’ experiences to improve their preparedness to professional life. The study indicated that the competencies of prospective teachers towards the profession of teaching were generally positive. It was observed that several factors affected prospective physical education and sports teachers in their preparedness for teaching. Thus, it is important to ensure that prospective physical education and sports teachers gain acquisitions for their general competencies in the profession of teaching before they complete their undergraduate education.
Konstantinopolis, Orta Çağ boyunca kültürel, politik, ekonomik ve dini bir merkez olma özelliği göstermektedir. Çok sayıda yabancının asker, tüccar, köle, elçi olarak şehre geldiği görülür. ...Yabancıların şehir yaşamındaki etkinlikleri ve ağırlıkları konusunda ise farklı değerlendirmeler söz konusudur. Her ne kadar İtalyalılar, Müslümanlar ve Slavlar gibi ağırlıklı olarak ticari ve askeri etkinlikler için şehre gelenlerin nitelikleri konusunda daha net fikirlere sahip olsak da Yahudiler ve Ermeniler gibi vatandaşlık elde etmiş topluluklar hakkındaki değerlendirmelerimiz konusunda etnisite, nüfus ve asimilasyon ile ilgili iki temel problem göze çarpmaktadır. İlk problem, Bizans’ta görülen bir çeşit Romalı milliyetçiliğinin göz ardı edilmesidir. Yabancıların zaman zaman sorunlar yaşasalar da Bizans’ın bir parçası oldukları, dinsel ayrılıklar dışında benimsendikleri ve hatta imparatorlar çıkardıkları düşüncesi oldukça yaygındır. Ancak Romalılaşma ve asimilasyonun göz ardı edilmesi ve etnik köken ısrarcılığı bizi şehirdeki yabancılarla ilgili yanlış değerlendirmeler yapmaya itmektedir. Yabancılarla ilgili ikinci problem ise onların, Romalı nüfusa oranı ve karşılaştıkları tutumla ilgilidir. Şehirde yaşayan yabancılar küçük bir azınlığı oluşturmaktaydı ve buna rağmen yabancı karşıtlığı, isyanlar, tehcir ve izole yaşam alanları görülüyordu. Bu durum bizi Konstantinopolis’in çok uluslu, kozmopolit bir şehir olduğu düşüncesini sorgulamaya iter. Dolayısıyla çalışmamızda şehirdeki yabancı toplulukların yaşamları ve etkinlikleri anlatılırken, bir yandan da onların asimilasyonları ve toplumsal statüleri incelenmiştir.
Constantinople was a cultural, political, economic and religious center throughout the Middle Ages. It is seen that many foreigners came to the city as soldiers, merchants, slaves and ambassadors. There are different evaluations about the activities and weights of foreigners in city life. Although we have a clearer idea of the qualifications of those who came to the city mainly for commercial and military activities, such as Italians, Muslims and Slavs, two main problems with ethnicity, population and assimilation stand out in our assessment of citizenship-acquired communities such as Jews and Armenians. The first problem is the neglect of the kind of Roman nationalism found in Byzantium. Although foreigners have problems from time to time, it is quite common to think that they are a part of Byzantium, they are adopted outside of religious differences and even they have emperors. However, the ignorance of Romanization and assimilation and the insistence on ethnicity push us to make wrong assessments about foreigners in the city. The second problem with foreigners is their ratio to the Roman population and the attitudes they encounter. Foreigners living in the city were a small minority, and yet there was xenophobia, riots, deportations and isolated living quarters. This situation forces us to question the idea of Constantinople as a multinational, cosmopolitan city. Therefore, in our study, while explaining the lives and activities of foreign communities in the city, their assimilation and social status were examined.
Objective Coronary artery bypass grafting （CABG） is gradually increasing in the elderly population. We aimed to investigate the risk factors and the results of CABG along with the long term survival ...in patients at an age of 80 and older. Methods Between Januaa-y 2002 and December 201 I, a total of i01 consecutive patients at an age of S0 and older who underwent CABG in our hospital were included in the study. The patients were followed and the long-term survival was estimated. Results The mean age of the patients was 82.98 ~ 2.27 years. Sixty-four （63.4%） were males and 37 （36.6%） were females. Emergency surgery, duration of cardiopulmonary bypass, the intensive care unit （ICU） stay, inotropic support, intra aortic balloon pulsation application, amount oferythrocyte transfusion and flesh frozen plasma transfusion and ventilation period were significantly higher in the patients who died in the hospital. The duration of cardiopulmonary bypass （CPB） was found to be an inde- pendent predictor of mortality （OR： 1.18, 95% CI 1.01-1.38, P = 0.034）. The in-hospital mortality was 16.8%. Kaplan-Meier analyses revealed a survival ratio of 91.3% at one year, 82.9% at three years and 69.0% at five years. Conclusions Patients at the age of 80 and older can be candidates for the CABG procedure bearing in mind that they may have a longer ventilation period and intensive care unit stay. The morbidity and mortality of this age group is considered within an acceptable range. Approaches to minimize CPB, or the choice of off-pump surgery, may be a preventive method to lower the incidence of mortality. Hence, CABG may be performed in this age group with a satisfactory survival ratio.
Objective: To evaluate the long-term balance outcomes of vestibular nerve section (VNS) and labyrinthectomy (L) operations. The indirect outcomes will be the correlation of objective and subjective ...test results and an analysis of anterior-posterior versus medial-lateral computerized posturography (CP) scores. Methods: This retrospective study evaluated objective CP and subjective Dizziness Handicap Inventory (DHI) results of patients who underwent VNS and L surgeries for Meniere's disease. Results: A total of 55 (31 VNS and 24 L) patients were included in the study. The two operation groups were similar in terms of age, and mean time between surgery and the tests (p=0.465 and p=0.616) respectively. The vestibular and global scores at anterior-posterior CP showed statistically significant differences between the groups (p=0.000 and p=0.007) respectively in favor of the VNS group. In addition, the comparison of the vestibular CP scores of anterior-posterior and medial-lateral evaluations of the entire study population was lower in the medial-lateral evaluation (p=0.000). The mean DHI scores did not show statistically significant differences (p=0.359) between operation groups, nor did the correlation analysis between CP and DHI scores reveal statistical significance (p values >0.05). Conclusion: In the long term, objective balance outcomes are better for VNS patients than for L patients. Additionally, medial-lateral balance outcomes are more affected than anterior-posterior balance outcomes from unilateral ablative surgeries. Subjective balance perception is not different between the two surgery groups, and DHI scores do not show a correlation with CP scores. Keywords: Meniere's disease, vestibular nerve, labyrinth, surgery, postural balance, dizziness, disability evaluation
Bize ulaşan en eski kaynaklardan anlıyoruz ki insanoğlu; statüsü, ırksal özellikleri, kültürü, dini vs. konumuna göre muhataplarını öz isimleri yanında birçok farklı adlandırmalarla anar olmuşlardır. ...Araştırmamızın temel konusu olan Arapça lakap ve unvanlar da izah ettiğimiz bu zaruretin sonucu olarak ortaya çıkmıştır. İslâm kültür ve medeniyetinin teşekkülünden önce Bizans ve Sâsâni imparatorlukları başta olmak üzere bütün medeniyetlerde özellikle seçkin sınıf olarak kabul edilen grup mensupları için isimleri dışında farklı unvanlar kullanılmıştır. Elbette cahiliye Arap toplumu da bundan fazlası ile etkilenmiştir. İslam’ın hızlı bir şekilde yayılışı ve farklı medeniyetlerden etkileşimle oluşturduğu siyasî ve bürokratik yapı içerisinde dini figürleri kullanılarak yeni bir adlandırma daha doğrusu lakaplandırma yoluna gidilmiştir. Öyle ki, birçok yöneticinin asıl ismi gölgede kalmıştır. Emevî devletinin katı merkeziyetçi yapısı aşırı bir taltife veya tanımlamaya ihtiyaç duymayacak otoriter bir devlet yönetimini gerekli kılmaktaydı. Dolayısıyla halifenin kendini tanımlaması için ekstra bir lakap veya unvana çok da ihtiyacı yoktu. Abbâsî ihtilali ile birlikte siyasî anlayıştaki köklü değişim isimlendirme stratejilerinde de büyük bir başkalaşmaya yol açmıştır. Aslında bu yönetim anlayışındaki farklılaşmayı en kısa yoldan unvanlar üzerinden anlatmak mümkündür. Abbâsî halifelerinin şöhrete kavuşmuş isimleri lakaptan başkası değildir. Allah lafızları ile bezenmiş bu isimler aslında tebaaya dini hassasiyeti gösterme gayretinden ibarettir. Diplomasi dilindeki hassasiyet kurulan özel dîvânlarla daha da ön plana çıkmıştır. Din dili ile siyaset dili iç içe girmiş, yaratıcının yeryüzündeki temsilcisi konumda olan halife etrafına lakaplar/unvanlar dağıtır olmuştur. Bu uygulamanın fiili durumunu vasal devletlerle ilişkide müşahhas olarak görmekteyiz. Abbâsîler döneminde öncelikle yarı bağımsız daha sonra bağımsız olarak ortaya çıkan devletlerle hilafet arasındaki ilişkilerin düzeyi zaman ve şartlara göre farklılıklar arz etmiştir. Abbâsî devletinin siyasi gücü ile orantılı olarak bu devlet başkanlarına değişik payeler verilmiştir. Bu araştırmada Horasan ve Mâverâunnehir bölgesinde kurulan siyasi anlamda oldukça önemli faaliyeteler yürüten vasal devlet hükümdarlarına verilen unvanların arka planı ortaya konmaya çalışılacaktır. Türk tarihi açısından da oldukça önemli olan ve bölge ile hilafet merkezi Bağdat arasında köprü vazifesi gören Tâhiriler, Sâffâriler ve Sâmânilerin siyasi, dinî, sosyal yapısının daha sağlıklı anlaşılması adına önemli tespitler ortaya konmaya çalışılmıştır. Bu üç vasal devletin yıkılışı akabinde kurulan Türk imparatorluklarının siyasi ve bürokratik şekillenmelerindeki tarihsel sürecin bilinmeyen yönlerini keşfetme adına ele alınan konunun ehemmiyet arz ettiğini düşünüyoruz. Aslında bugün dahi farklı İslam coğrafyalarında statü tayini ve siyasi alanın tertibi açısından kullanılan payelerin tarihi anatomisinin keşfedilmeye çalışıldığı söylenebilir. Her şeyden önemlisi burada mevâlinin Arap iktidarı ile iletişim boyutunun köşe taşları keşfedilmeye çalışılmıştır. Mâverâunnehir ve Horasan coğrafyalarının İslâm fetihleri öncesi konumu ve özellikle Türk göçleri ile hızlanan nüfus akışkanlığı bölgenin Abbasîler dönemi siyasî oluşumunda önemli bir faktör olmuştur. Vasal devlet hükümdarlarına verilen unvanlarda tarihsel arka plan göz önünde tutulmuştur. Mısır’da kurulan bir Türk devlet başkanına halife tarafından eski Türk kültüründeki İhşid unvanının veriliyor olması dikkate şayan bir durumdur. Doğudaki vasal devletlerde buna benzer daha bir çok örnekle karşılaşma imkânımız vardır. Çalışmamızdan elde ettiğimiz çıkarım hilafet merkezi ile bağlı devletler arasında siyasî bağlantıda unvanların belirleyici bir rol üstlenmiş olmasıdır. Bu bir taraftan merkezle yerel yöneticiler arasındaki balansı düzenlerken diğer taraftan halkın gözünde sultanların maddi olduğu kadar manevi mertebesini tayin etmektedir. Aslında fetihlerdeki başarılar halifelerin vasal sultanları unvanlarla rütbelendirmesine yol açmıştır. Bu durum dini otorite olan hilafetle dünyevi otorite arasındaki dengeyi belirleyen bir nevi parola niteliğindedir.
We understand from the oldest sources that have reached us that according to their status, racial characteristics, culture, religion etc. people called their adressees with many different names besides their own names. The Arabic nicknames and titles, which are the main subject of our research result of this necessity. Before the formation of Islamic culture and civilization, different titles were used in all civilizations, especially in the Byzantine and Sassanid empires, for the members of the group, which were considered as the elite class, apart from their names. Of course, the Arab society of jahiliyyah was also greatly influenced by his. In the political and bureaucratic structure created by the rapid spread of Islam and the interaction from different civilizations, a new naming, or rather nicknames, were made by using religious figures. This happened to such extend that the original names of many rulers remained in the shadows. The strict centralist structure of the Umayyad state required an authoritarian state administration that would not need excessive credit or definition. Therefore, the caliph did not need an extra nickname or title to define himself. At the same time, it would be appropriate to say that they never had any thoughts of praising the politicians and bureaucrats affiliated with them. The radical change in the political understanding with the Abbasid revolution also led to a great change in naming strategies. In fact, it is possible to explain the differentiation in this management approach through titles in the shortest way. The famous names of the Abbasid caliphs are nothing but nicknames. These names, which are adorned with the words of Allah, are actually an effort to show religious sensitivity to the subjects. The sensitivity in the language of diplomacy has come to the fore even more with the special divans established. The language of religion and the language of politics have been intertwined, and the caliph, who is the representative of the creator on earth, has been giving nicknames/titles around him. We see the actual situation of this practice as concrete in relation to the vassal states. During the Abbasid period, the level of relations between the states, which first emerged as semi-independent and later independent, and the caliphate differed according to time and conditions. In proportion to the political power of the Abbasid state, these heads of state were given different ranks. In this research, we try to reveal the background of the ranks given to the heads of vassal state established in the Khorasan and Transoxiana region and carrying out very important activities in the political sense. Additionally, we aim reveal to find out the political, religious and social structure of Tahirids, Saffarids, and Samanids, who are also very important in terms of Turkish history and serve as a bridge between the region and the center of the caliphate, Baghdad. We think that the subject discussed is important in order to discover the unknown aspects of the historical process in the political and bureaucratic formation of the Turkish empires established after the collapse of these three vassal states. In fact, it can be said that even today, the historical anatomy of the ranks used in terms of status determination and the arrangement of the political field in different Islamic geographies is being explored. Most importantly, in this study, we try discover the cornerstones of the communication dimension of the mawali with the Arab power. The location of the Transoxiana and Khorasan geographies before the Islamic conquests and the population fluidity accelerated by the Turkish migrations were an important factor in the political formation of the region during the Abbasid period. The historical background was taken into consideration in the titles given to the vassal state rulers. It is remarkable that the caliph gave the old Turkish title “ıhsid” to a Turkish leader of a state established in Egypt. There are many other examles such as this with regard to the vassal states in the East. The conclusion we have obtained from our study is that titles play a decisive role in the political connection between the center of the caliphate and the affiliated states. On the one hand, this regulates the balance between the center and local administrators, on the other hand, it determines the moral as well as the material rank of the sultans in the eyes of the people. In fact, the successes in the conquests led the caliphs to rank the vassal sultans with titles. This situation is a kind of password that determines the balance between the religious authority, the caliphate, and the worldly authority.
We understand from the oldest sources that have reached us that according to their status, racial characteristics, culture, religion etc. people called their adressees with many different names ...besides their own names. The Arabic nicknames and titles, which are the main subject of our research result of this necessity. Before the formation of Islamic culture and civilization, different titles were used in all civilizations, especially in the Byzantine and Sassanid empires, for the members of the group, which were considered as the elite class, apart from their names. Of course, the Arab society of jahiliyyah was also greatly influenced by his. In the political and bureaucratic structure created by the rapid spread of Islam and the interaction from different civilizations, a new naming, or rather nicknames, were made by using religious figures. This happened to such extend that the original names of many rulers remained in the shadows. The strict centralist structure of the Umayyad state required an authoritarian state administration that would not need excessive credit or definition. Therefore, the caliph did not need an extra nickname or title to define himself. At the same time, it would be appropriate to say that they never had any thoughts of praising the politicians and bureaucrats affiliated with them. The radical change in the political understanding with the Abbasid revolution also led to a great change in naming strategies. In fact, it is possible to explain the differentiation in this management approach through titles in the shortest way. The famous names of the Abbasid caliphs are nothing but nicknames. These names, which are adorned with the words of Allah, are actually an effort to show religious sensitivity to the subjects. The sensitivity in the language of diplomacy has come to the fore even more with the special divans established. The language of religion and the language of politics have been intertwined, and the caliph, who is the representative of the creator on earth, has been giving nicknames/titles around him. We see the actual situation of this practice as concrete in relation to the vassal states. During the Abbasid period, the level of relations between the states, which first emerged as semi-independent and later independent, and the caliphate differed according to time and conditions. In proportion to the political power of the Abbasid state, these heads of state were given different ranks. In this research, we try to reveal the background of the ranks given to the heads of vassal state established in the Khorasan and Transoxiana region and carrying out very important activities in the political sense. Additionally, we aim reveal to find out the political, religious and social structure of Tahirids, Saffarids, and Samanids, who are also very important in terms of Turkish history and serve as a bridge between the region and the center of the caliphate, Baghdad. We think that the subject discussed is important in order to discover the unknown aspects of the historical process in the political and bureaucratic formation of the Turkish empires established after the collapse of these three vassal states. In fact, it can be said that even today, the historical anatomy of the ranks used in terms of status determination and the arrangement of the political field in different Islamic geographies is being explored. Most importantly, in this study, we try discover the cornerstones of the communication dimension of the mawali with the Arab power. The location of the Transoxiana and Khorasan geographies before the Islamic conquests and the population fluidity accelerated by the Turkish migrations were an important factor in the political formation of the region during the Abbasid period. The historical background was taken into consideration in the titles given to the vassal state rulers. It is remarkable that the caliph gave the old Turkish title “ıhsid” to a Turkish leader of a state established in Egypt. There are many other examles such as this with regard to the vassal states in the East. The conclusion we have obtained from our study is that titles play a decisive role in the political connection between the center of the caliphate and the affiliated states. On the one hand, this regulates the balance between the center and local administrators, on the other hand, it determines the moral as well as the material rank of the sultans in the eyes of the people. In fact, the successes in the conquests led the caliphs to rank the vassal sultans with titles. This situation is a kind of password that determines the balance between the religious authority, the caliphate, and the worldly authority.
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