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Tasarlama eyleminin tasarım araçları modeli üzerinden bir okuması
Get PDFDesign discipline is dominated by a variety of physical, digital, conceptual, literal and hybrid tools. Whether suppressed or exposed, developed or borrowed, simple or complex tools dominate design activity. This paper aims to provide an in-depth analysis on design relevant issues and their contextual interpretations while enabling an insight on the nature of design behavior. The objective is to develop a model based on thorough dissections of the highly ambiguous architectural design process. The framework of the paper can be clarified by the following assumption: contrary to the highly advocated linear and sequentially structured model of design, a diachronic and non-linear model of design possess more potential when a wicked design problem and its solution process are concerned. This assumption is mutually valid for interior design, landscape design, architectural design and product design disciplines. The thesis argues that a design model based on a set/variety of tools and ever evolving subjective designerly strategies on their implementations will provide a comprehensive picture of any particular design process. Hence, the paper is based around discussions on the tool-based approach to understand the latent context of design behavior to support design education and design critique. The model could further be developed to aid analysis of the precedents. An analytical dissection approach is adopted as the method of the work, In other words the methodology includes literature analysis, analysis of verbal proposals and visual representations. The model is based on the assumption that designing subject, as a team or a person, uses tools to design. Hence we may represent a semantic relation: 'subject tool object'. This relation may be written alternatively as' f(subject)=object'. The function signifies design tool. If the ontological meanings of subject, tool and object is studied thoroughly an indirect picture of design activity may be available to further study and analysis of design activity and design process that are used during this activity. The methods, techniques, objects, cognitive machinery, algorithms, representations, visualizations, knowledge base, precedents, visualization tools, moods, and environments mediating between designer and designed object are transformed or adapted as design tools. The subject situated in the design space which is defined by similar problems and solutions learns to navigate in it, choosing one of the potential actions, selects a appropriate tool, transforms the objects gradually towards its final stage according to its own proposed agenda, since the agenda itself is a part of design product likewise the design process. The subject, the tool, and the object are all situated in design space. Their meanings and functions are dynamic and shifts according to situations. Hence design activity is extremely situated. Design space includes precedents or previously experienced similar examples or design fragments that are used as raw materials to be tweaked, modified, and appropriated. If there isn't any appropriate tool or fragment available, new ones are generated or abducted. The consequence of using new tools designing a product is attracting the attention of the critics and the other designers while the products take its appropriate place in design history. The subject and tools may merge; in fact subject may be defined as a collection of past experiences and cognitive tools. Design tools are cognitive in essence as well. The cyclic nature of the self who creates tools that recreates the self is of a great importance for designer and design activity. Designer is situated surrounded and defined by the tools available; it is not above or outside of the design space. According to the model the he needs of the users, wind effects and all the other realities and limitations of design space are not working against the subject but within it. The tools and object may merge; object carries the signs of the tools that are created it. As the tools available increase in variety potential of appropriateness of the object to the problem is increased as well. As the design tools are better comprehended, redesigned, evolved and thrived our designing technology and potential to find appropriate solutions to modern day complex and contradictory design tasks. The benefits of the model are suggestion to some implementations in design education and critical studies of design. Since the knowledge base is appropriated as a design tool during design process, all course material is subject to customization. Keywords: Architectural design, design research, design process.Bu çalışmada, tasarlama eylemini anlamak, tasarımın doğasına ilişkin konuları yorumlayıp nihayetinde tasarlama becerilerimizi geliştirebilmek için tasarım sürecini açıklayan bir model önerilmektedir. Literatürde sıkça rastlanan önceden belirlenmiş doğrusal ve ardışık zamanlı karar dizilerine dayalı bir model yerine, eşzamanlı, duruma göre değişen, doğrusal olmayan, hiyerarşik olmayan ve içkin bir model önerilmektedir. Bu modelin, özellikle iyi tarif edilmemiş ve ‘muzip’ sorunlarla ilgilenen mimari tasarım, ürün tasarımı, iç mimarlık, peyzaj tasarımı gibi gelenekselleşmiş tasarım alanlarında yaygın olarak kullanılan tasarlama şeklini anlamak için daha geçerli olabileceği tartışılmaktadır. Tasarımın konusunun tarif ettiği durum içerisinde, öznenin nesneyi tasarlarken seçip, geliştirip, kullandığı tasarım araçları ve bu araçların bıraktığı izlerin yardımıyla tasarım eylemine ilişkin süreçlerin açımlanması, tasarlama bilgisinin derlenmesi ve aktarılmasına imkân veren bir iletişim zemini kurulabilmektedir. Tasarım bilgisinin tasarım araçları aracılığıyla kişiden kişiye, kuşaktan kuşağa aktarıldığı savıyla, tasarım araçları tasarım eğitimin kurgulanmasında önemli bir yer edinebilir. Tasarım araçları odaklı bir bakış açısıyla tasarım eğitiminin odağı sonuç üründen tasarlama eyleminin sürecine doğru kayacaktır. Aynı bakış açısı tasarım ürünlerinin tarihsel önemini ve güncel konumunu eleştirirken tasarım nesnelerinin üretiminde kullanılan ve geliştirilen araçların izi sürülerek işin tasarım kültüründeki yerinin belirlenmesinde bir altlık olarak kullanılabilir. Tasarım tarihi yazımında ise araçların oluşum, aktarım, gelişim süreçlerinin izi sürülerek doğrudan güncel tasarlama süreçlerine veri sağlayan farklı ve yaşayan bir anlatı elde edilebilir. Anahtar Kelimeler: Tasarım, tasarım araştırmaları, tasarım süreci
19. yüzyılda Kastamonu Eyaleti'nde hükümet daireleri
Get PDFWestern impact on the Ottoman Empire was transformed to western influence through out the 18th. century and in the 19th century this influence has spread to different areas of Ottoman bureaucracy leading to the constitutional changes and formation of ministries. Westernization of the government and institutional changes such as the constitution of municipalities, led to the formation of new governmental buildings. Especially the reforms of Tanzimat period and the constitution of states had great impact on the public. The new institutional system and the changes in the government led to a different partition of land of the Empire. Kastamonu, which was a part of Anatolia Province till then, was transformed into a province (eyalet) in 1844. The new province consisted of a region of four sub-provinces (sancak); Kastamonu, Sinop, Bolu and Kengırı (Çankırı). These sub-provinces were further divided into towns (kaza) and villages (nahiye). This categorization of the settlements was kept until the formation of Turkish Republic which transformed sub-provinces into cities. This research aims to explore the historical governmental buildings within the borders of 19th. century Kastamonu Province, comparing the differences and the similarities of the edifices. The defined area of 19th century Kastamonu Province, today consists of 8 cities. To explore the existence of governmental buildings in the settlements, literature and archive researches were made. Yearbooks of 19th century Kastamonu Province (Kastamonu Vilayet Salnamesi) have been an important source of information related to the topic. Through this research, a building list has been created and a field study has been performed in the sub-provinces and towns of the period, in order to determine the present day situation and the architecture of the historical buildings. The conclusion of the fieldwork is that out of 24 known to exist, 12 historic governmental buildings are remaining in the region today.The outcomes of the study can be summarized as follows: -The government buildings in sub-provinces(sancak) (Kastamonu, Bolu, Sinop, Çankırı) and the ones constructed in towns (kaza); (Kastamonu Araç, Cide, Daday, Taşköprü, Bolu Göynük, Çankırı Ilgaz, Karabük Safranbolu, Bartın Amasra) have both similarities and differences regardless of the settlements. -19th century government buildings are two or three storeyed buildings with basements. Most of the governmental buildings are masonry with a few exceptional timber framed ones (Kastamonu Daday and Çankırı). All of them are symmetrical and the plan scheme is mostly rectangular. Plans of the buildings consist of rooms which open to a corridor in the middle. The staircase is usually in the opposite side of the corridor to the entrance, with service areas on the sides. The main colonnaded entrances of the buildings are in the middle of the facades, emphasized with projections on the upper floor. The doors and windows have great heights in accordance with the heights of the ceilings. Windows and doors are mostly pointed or flat arched. Hipped roofs are common in some examples with parapet walls. The common features of architecture of masonry edifeces are stone pilasters and casings. Band courses and cornices are present in all of the buildings. -The most important difference between the sub-province and town government buildings is the size of the artifacts. The sub-province buildings are bigger and have more rooms, they also have more storeys than the others. -Most of the non-existing buildings’ plots are used for the construction of new governmental buildings of 20th century. -The similarities in the government buildings of the province brings the possibility of type-projects implementation. There are not enough evidence to prove it but the architectural system of the period, city architects and the centralization works of the government, support this thesis. Yet more archival research must be performed. The buildings keep their original functions which is an important aspect of preservation for the maintenance of historical buildings. In case there will be a reuse for these buildings, new functions must be evaluated thoroughly. The continuity of the original usage of the plot (in Bolu government building case,) emphasizes the importance of the buildings for the public. In this respect, these buildings stand as architectural reflections of westernization and modernization phenomena that took place under difficult economic circumstances in 19th century. Built as symbols for the existence of an emporership, they must be kept and cared for as historic evidences of our history for the next generations. Keywords: Government buildings, 19th century, Kastamonu Province.19. yüzyıl, Osmanlı Devleti’nde yönetim sisteminin değişerek 17. yüzyılda başlayan Batılılaşma etkilerinin, İstanbul ve taşrada yeni yapı tipleri ile birlikte uygulanmaya başlandığı bir dönemdir. Kastamonu Eyaleti, 1844 yılında idari sistem değişikliği sonucunda Anadolu Eyaleti’nden ayrılarak, yeni bir yönetim alanı olmuştur. Kastamonu Eyaleti, Kastamonu, Bolu, Sinop, Kengırı (Çankırı) sancaklarından oluşmaktadır. Bu çalışmada amaç, Osmanlı Devleti’nin son dönem modernleşme çabalarının mimarideki yansımaları olan ve devletin yeniden yapılanmasının fiziksel ögeleri olan bu yapıların mimari özelliklerinin araştırılması ve günümüzdeki durumlarının tespitidir. Yeni bir yönetim sisteminin uygulanacağı kamusal mekânlar olarak ortaya çıkan bu yapılarda, geleneksel Osmanlı mimarisinden farklı plan ve cephe düzenleri uygulanmıştır. 19. yüzyılda Kastamonu Eyaleti sınırları dahilindeki sancak ve kaza merkezlerinde inşa edilen hükümet dairelerinden günümüze kalanlar bu çalışmanın konusunu oluşturmaktadır. Araştırma literatür taraması ve alan çalışması olarak iki temel süreç biçiminde tasarlanmış olup, bu yöntem doğrultusunda, yerleşim merkezlerine ait her türlü yazılı dökümana başvurulmuş, Kastamonu Vilayet Salnameleri taranmış ve arşiv çalışmaları gerçekleştirilmiştir. Yayın incelemelerinin ardından bu araştırmalarda elde edilen sonuçlara dayanarak, alan çalışması gerçekleştirilmiş, yapılar yerlerinde tespit edilmiştir. Alan sınırları dahilinde günümüzde 11 hükümet dairesi tespit edilmiştir. Bunlardan dördü, sancak merkezlerinde, diğerleri ise kaza merkezlerinde inşa edilmişlerdir. Bu araştırmayla, 19. yüzyılda inşa edilen hükümet dairelerinin günümüze ulaşan örneklerinin, gelecek kuşaklara aktarılması gereken tarihi öneme sahip olduklarını ortaya koymuştur. Anahtar Kelimeler: Hükümet dairesi, 19.yüzyıl, Kastamonu Eyaleti
Economic globalization and convergence in regional productivity rates in Turkey
Get PDF1970’lerden bu yana yaşanan haliyle ekonomik küreselleşme, dünya kentlerinin ekonomideki rolünü artırmış, küresel bir kentsel sistem ortaya çıkmıştır. Gelişmiş ve gelişmekte olan ülkelerde ekonomik gelişme dış ticarette avantajlı metropoliten alanlar ve çeperinde gerçekleşmekte, bölgelerarası farklılıklar sürmektedir. Neo-klasik bölgesel büyüme kuramına göre uzun vadede ülkeler veya bölgeler arası farklılıkların azalacağı öngörülmektedir. İçsel Büyüme Teorileri ise teknolojik gelişmeyi dışsal bir unsur olarak gören bu kurama karşı çıkarak, beşeri sermayeye bağlı olarak yerel bilgi birikimi ve yayılması süreçlerinin bölgesel üretkenlik farklılıkların sürmesine neden olabileceğini ileri sürmüşlerdir. Ampirik bulgular, mekansal yayılma etkileriyle bir bölgenin komşusu olan diğer bölgelerde de üretkenlik artışına etkisi olabileceğini göstermektedir. Türkiye’ye dair çalışmalar 1995 öncesi dönemde bölgesel üretkenlikte yakınsama olduğunu ve birinci derecede komşu illerin gelişmelerinin diğer iller üzerinde olumlu etkileri olduğunu göstermiştir. Ancak Doğu-Batı farklılıklarının sık sık dile getirildiği Türkiye’de mekansal taşma etkilerinin salt en yakın komşu illerle sınırlı olmadığı düşünülmelidir. Ayrıca beşeri sermayenin bölgesel üretkenlik artışları üzerinde etkisi olduğu da bilinmektedir. Bu etkenin 1990-2000 döneminde de bölgesel büyümeye etkili olduğu düşünülebilir. Bu varsayımları test etmek amacıyla 1990-2000 dönemi için bir koşullu beta yakınsaması modeli önerilmiş, beşeri sermayenin ve 500 km içindeki komşuların başlangıçtaki üretkenlik düzeylerinin illerin büyümesindeki rolü incelenmiştir. Sonuçta, başlangıçta kendisi düşük ancak komşuları yüksek üretkenliğe sahip illerin daha hızlı geliştikleri, ortalamanın üzerindeki beşeri sermaye birikiminin üretkenliğe olumlu etkisi olduğu anlaşılmıştır. Sonuçlar, yakınsamaya işaret etse de, bölgesel büyümenin gelişmiş merkezler çevresindeki az gelişmiş bölgelerde daha güçlü olduğunu ortaya koymaktadır. Anahtar Kelimeler: Ekonomik küreselleşme, bölgesel dengesizlikler, yakınsama, üretkenlik, beşeri sermaye.Economic globalization since 1970'es have increased the importance of world cities in the global economy, and a global urban system has emerged. Economic development is clustered in metropolitan regions and their periphery, which have certain advantages for international trade, such as proximity and historical connections; leading to sustaining regional inequalities. In this context, core, semi-peripheral and peripheral areas form a global economic system. Trans-national companies and transformation of production systems into more flexible forms play key roles in this spatial restructuring processes. Turkey's integration to the global economy which gained impetus in the post 1970 period has likely lead to similar spatial developments. The Neo-classical regional growth theory foresees a decrease in regional inequalities among countries or regions in the long run, due to decreasing returns to capital.. According to Solow's growth model, initially poorer regions grow faster and catch-up with richer regions. Endogenous growth theories reject the Neo-classical theory which assumes technology as a purely exogenous process, and propose that regional inequalities in productivity rates could be persistent due to local knowledge growth and diffusion, or, growth of human capital. Post-neo-classical empirical findings furthermore show that productivity growth may not be limited to a region and spatial spillovers may lead to growth of productivity in neighbor regions. Empirical studies about Turkey provide evidence of productivity convergence and first order neighbor region effects on productivity growth in the pre-1995 period. However, it should not be thought that spillovers are effective only for first order neighbors in a country like Turkey, where sharp differences between Eastern and Western provinces are observed. Spatial spillover effects may span longer distances, as evident elsewhere in the world. Apart from such spillovers empirical studies on Turkey have also demonstrated that human capital has an effect on per capita productivity growth in Turkey in the pre-1995 period. It is thought that this is still an important cause of productivity growth at the regional level, in the period 1990-2000. Three questions are asked regarding theoretical approaches and empirical findings on Turkey. Has regional inequalities in productivity rates decreased, or, in other words, is there beta convergence in Turkey during 1990-2000? Do long distance spatial spillovers have an impact on regional growth? And last, but not the least: Did growth of human capital have an effect on regional growth? In order to answer these questions, three variables are identified and a conditional beta convergence model is specified. The model is in the form of a log-linear cross-sectional model where the dependent variable is the productivity growth per worker in a region. Furthermore, it incorporates neighborhood effects within 500 km. Particularly, the model incorporates the influence of initial productivity levels of neighbor regions on growth of productivity within a region. A preliminary Moran's I test demonstrates that there is significant but weak spatial autocorrelation between the initial per worker productivity levels of neighbor regions and the growth rate of per worker productivity in a region. The model is estimated by using an OLS estimation procedure. The result is an adjusted R2 of 0.39. Usual tests like Breusch-Pagan and White tests show that heteroskedasticity is not a problem and Jarque -Bera test is not significant. Therefore, the model is thought to be thoroughly specified. Findings suggest that initially poorer regions grow faster, pointing to convergence. The speed of convergence is about 1.89% per annum, which indicates a half-life of approximately 37 years. The result suggests that the inequalities between productive and less productive regions are decreasing slowly. As expected, initial productivity levels of neighbor regions have a positive impact on growth of productivity in a region. Therefore, it could be concluded that spatial spillovers reach far distances, leading to growth in semi-peripheral areas. The strongest impact on productivity growth belongs to the human capital variable. Excessive growth of per worker scientific and technical professionals is an important determinant of productivity growth. Although the results suggest conditional convergence, they also point that regional growth is stronger in regions around developed metropolitan regions. Regional inequalities are likely to persist between East and West for a long time. Keywords: Economic globalization, regional inequalities, convergence, productivity, human capital
Gözenekli ortamlarda taşınım olayı
Get PDFTransport phenomena in porous media has received much attention in recent years because of its important role in a large variety of engineering and technical applications which span from the transport processes in biomechanical systems, such as blood flow in the pulmonary alveolar sheet, to the large scale circulation of brine in a geothermal reservoir. There is no doubt that this new branch of convective heat transfer keeps attracting engineering and scientists from diversified disciplines such as mechanical engineering, chemical engineering, civil engineering, nuclear engineering, aerospace engineering, bio engineering, food science and geothermal physics. Porous materials are encountered everywhere in everyday life, in technology, and in nature. A material can be defined as a porous medium if the material has the following properties, Dullien (1992): a) The material must contain relatively small spaces, called pores or voids, imbedded in the solid or semi-solid matrix. The pores usually contain some fluid, such as air, water, etc., or a mixture of different fluids, b) The fluids should be able to penetrate through one face of the material and emerge on the other side. Building materials, such as bricks, concrete, limestone, sand stone, soil, lungs and bones are examples of porous materials encountered in practice. All macroscopic properties of porous media are influenced by the pore structure. Macroscopic pore structure parameters represent average behaviour of a sample containing many pores and the some important pore structure parameters are the porosity, the tortuosity and the permeability. The porosity and the tortuosity are the characteristics of a porous medium; the permeability is the mass transfer property of the porous media. Porosity, e, is the fraction of the bulk volume of the porous material that is occupied by the pore space. Depending on the type of the porous medium, the porosity may vary from near zero to almost unity. Measurement of porosity is made by using several techniques, such as imbibition, mercury injection and gas injection methods give an effective porosity value. The porosity is the most important property of a porous medium and it affects most of the physical properties of the medium. For a homogeneous porous medium, the porosity may be a constant. But in general, the porosity is space dependent. Each void in the porous medium is connected to more than one other pore (interconnected), connected only to one other pore (dead end), or not connected to any other pore (isolated) and fluid flows through the interconnected pores. Tortuosity is used for the two-dimensional simulation of the porous medium. It is not a physical constant and depends on other porous media characteristics, such as porosity, pore diameter, channel shape, etc. Also, tortuosity depends on processes occurring during mass transfer and on the kind of material being transferred. In the simplest situation a porous medium can be considered as a bundle of capillaries. In this case, tortuosity is the ratio of the pore length to the porous medium thickness. It is difficult to determine tortuosity experimentally and in general, tortuosity is calculated by using the porosity and the effective diffusion coefficient or from the Kozeny coefficient, see Mota et al. (1999). The permeability, K, is the measure of the flow conductance of the porous medium and it is defined by the Darcy law and can be written by using porosity as Equation (9), see Ergun (1952). The permeability is independent of the nature of the fluid but it depends on the geometry of the porous medium and the measurement of the permeability can be achieved in the case of an isotropic media. Both liquids and gases have been used to measure permeability. Liquids sometimes change the pore structure and so it affects to the permeability. Keywords: Poroius media, porosity, permeability, Darcy's law, conservation equations.Gözenekli ortamlar günlük hayatımızda her sahada karşımıza çıkmaktadır. İçinden bir akışkanı geçirebilen gözenekli bir ortamda enerji geçişi ve akışkan akışı konusu bilim ve mühendisliğin çok değişik alanlarını ilgilendirmektedir. Bugüne kadar gözenekli ortamlar konusunda çok sayıda çalışma yapılmıştır. Ancak, günümüzde halen gözenekli ortamlarda hesaplanamayan ya da ölçülemeyen akış ve ortam özelliklerine yönelik çalışmalar yoğun olarak sürmektedir. Gözenekli ortamlardaki çalışmalar esas olarak Fransa'da Henry Darcy tarafından 1856 yılında bir hastaneye temiz su getirme projesi kapsamında yapılan çalışmaların daha sonra başka bilim adamları tarafından incelenip gözenekli ortamlarda akışı tanımlayan bir genel denkleme dönüştürülmesi ile başlar. Bu çağrılı çalışmada gözenekli ortamlarda kullanılan genel tanım ve temel denklemlerin tanıtılması esas alınmıştır. Bu çalışma gözenekli ortamlarla ilgili genel tanımlar ve gözenekli yapı içinde bir boşluk ve kati iskeletin olması sebebi ile oluşan mikroskobik boyuttaki içyapı düzensizliğinin çözümünü sağlayan Temsili Temel Hacim (TTH) kavramı tanımı ile başlamaktadır. Ortalama alarak mikroskobik seviyede taşınım olayının tanımı, Temsili Temel Hacim kavramı ile makroskobik ve sürekli ortam tanımlaması yapılarak elde edilmiştir. Bu çalışmada, gözenekli ortamlarda taşınımla ısı geçişi ve akısın matematiksel ve fiziksel temelleri, bu konuda iyi bilinen Darcy yasasından başlayarak ve onun yıllar içerisinde yeni düzenlemeleri He geliştirilerek anlatılmıştır. Bunlara ilaveten, bu çalışmada gözenekli ortam içinde kütle, momentum ve enerji geçişinin sürekli ortamlar yaklaşımı yaparak modellenmesi açıklanmaktadır. Çalışmanın sonunda gözenekli ortamlarda akışkan akışı ve ısı geçişi konusunda son yıllarda yayınlanan makaleler, kitaplar ve incelemeler hakkında bilgi verilmiştir. Anahtar Kelimeler: Gözenekli ortamlar, gözeneklilik, geçirgenlik, Darcy yasası, korunum denklemleri
Octacationic and supramolecular porphyrazines
Get PDFBu çalışmada oktakatyonik ve nona nükleer supramoleküler porfirazin kompleksleri sentezlenmiş ve spektral yöntemlerle karakterize edilmiştir. Hedeflenen oktakatyonik ve supramoleküler yapıların hazırlanması için daha önce çalışma grubumuz tarafından sentezlenmiş olan oktakis (2-hidroksietiltiyo) porfirazinatomagnezyum (MgOHPz) molekülü yeniden sentezlenmiştir. Supramoleküler yapının ilk basamağı olan MgOHPz molekülünün DCCI katalizörlüğünde piridin karboksilik asit ile kondenzasyonundan sonra oluşacak periferal konumda 8 tane piridin donör grubu içeren yeni bir porfirazin yapısı sentezlenmiş, ikinci adımda periferal piridinler kuaternize edilip okta katyonik yapıya ulaşılmıştır. Son aşama olarak da periferal piridinler üzerinden paramanyetik VO(acac)2 metal merkezleri ile koordinasyon bağları oluşturmak suretiyle nonanükleer supramoleküler sistemler elde edilmiştir. Ayrıca sentezlenen paramanyetik supramolekülün EPR yöntemi ile yapısı aydınlatılmıştır. Anahtar Kelimeler: Porfirazin, supramolekül, EPR, Kompleks.In this study, octacationic and nonanuclear supramolecular porphyrazines were synthesized and characterized by the common spectral methods. For the synthesis of target octacationic and supramolecular structures, first the octakis(2-hydroxyethylthio)porhyrazinatomagnesium (MgOHPz) which was required for the designing of the core of the supramolecule, was synthesized as given in the literature. The second step of the supramolecular structure was the addition of pyridyl donors on the periferal positions of the porphyrazine unit. For this purpose, MgOHPz was reacted with pyridine-4-carboxylic acid to give the ester units on the periferies of porphyrazine. Octakis (4-pyridoxyethylthio) porphyrazinato magnesium, (MgPyPz) was prepared by the complete esterification of all the OH-groups in MgOHPz with with pyridine-4-carboxylic acid (isonicotinic acid) in pyridine by the presence of dicyclohexylcarbodiimide and 4-toluenesulphonic acid as catalysts in seven days at ambient temperature. The blue-green color octakis(4-pyridoxyethylthio)porphyrazinatomagnesium, MgPyPz, was isolated with good yield. The octacationic molecule was obtained after the quaternization of the MgPyPz with iodomethane in the dark.The ready solubility of the product in water confirms the proposed structure. The nonanuclear supramolecule was prepared by the coordination reaction of the vanadylacetylacetonate, VO(acac)2 with MgPyPz and characterized by EPR technique together with the usual spectral data. Keywords: Porphyrazine, supramolecule, EPR, Complex
pH stabilization of Escherichia coli penicillin acylase by CMC conjugation
Get PDF90 kDa mol ağırlığında karboksimetilselüloz (CMC) ile konjuge olan Escherichia coli Penisilin G asilaz’ının sıcaklık ve pH’ya karşı geri dönüşümsüz inaktivasyonu çalışılmıştır. Karboksimetilselüloz periyodat oksidasyonu ile aktive edilmiş ve PGA’a, Schiff bazı oluşumu ile kovalent olarak bağlanmıştır. PGA ve modifiye olmuş PGA farklı zaman ve farklı pH değerlerinde (pH 4-9) inkübe edilmiştir. PGA’ın pH karşısındaki en yüksek stabilitesi, pH 8’de 4 kat olarak elde edilmiştir. CMC’un çapraz bağlanması sonucu PGA enziminin optimal pH ve kcat değeri değişmemiştir. Km, ve Vm değerleri ise azalmıştır. Konjuge PGA için farklı pH değerlerinde inaktivasyonun aktivasyon serbest enerjisi (ΔGi) PGA’nınkine göre daha yüksek bulunmuştur. Anahtar Kelimeler: Enzim stabilizasyonu, Escherichia coli, karboksimetilselüloz konjugasyonu, penisilin G asilaz.The irreversible inactivation of kinetics and the stability of Escherichia coli penicillin G acylase (PGA) at various pH values conjugated by anionic polysaccharide carboxymethyl-cellulose (CMC) were studied. The use of ionic polysaccharides in enzyme technology have many potential advantages, such as water solubility, biocompatibility and non-toxicity. The stabilizing effect of ionic polysaccharides on enzyme molecules is well known by causing the cross links between the free amino group containing amino acid residues on protein molecule and strengthening the electrostatic interactions on enzyme after conjugation. CMC was activated by periodat oxidation to its aldehyde derivative and covalently bound to PGA via Schiff's base formation. The 46% fraction of total enzyme activity and 65% fraction of total protein in PGA solution was conjugated by CMC. The amount of CMC bound protein was 33% of the initial CMC concentration. Native and CMC conjugated PGA were incubated at 40°C and different pH values between (4-9) interval for extended times. The irreversible inactivations of the native and conjugated PGA at pH values studied were obeyed to the first order inactivation kinetics. The highest pH stability of PGA was obtained at pH 8 as four fold. Cross-linking by CMC did not affect the pH profile and the kcat value of enzyme. However Km and Vm values were decreased after cross-linking. The activation free energy of inactivation (DGi) at different pH values for conjugated PGA were found to be always higher than that for native enzyme. CMC conjugation is improved the catalytic performance of enzyme by increasing the kcat/Km ratio. Keywords: Carboxymethylcellulose conjugation, enzyme stabilization, Escherichia coli, penicillin G acylase
Artificial neural network approach for modeling of the short range precipitation
Get PDFYağış kaynaklı doğal afetlerin önlenebilmesi ile su kaynakları ve havza yönetimi için yağışların ölçümü, modellenmesi ve tahminleri çok önemlidir. Kurulu olan yağış ölçer ağlarının hem zaman hem de uzay değişkenliklerinin yüksek olması sebebiyle, küçük ölçeklerdeki şiddetli yağışların belirlenmesinde çeşitli zorluklar vardır. Mevcut hava tahminlerinin son yıllardaki güvenilir sonuçlarına rağmen, konvektif yağışların zaman ve alan yağış desenleri tam olarak yakalanamamaktadır. Bu sebeple uydulardan elde edilen bilgiler hava tahmin modellerine girdi olarak kullanılmaktadır. Yağış tür ve miktarının uzaktan algılama ile belirlenmesi meteoroloji alanındaki önemli konulardan biridir. Bu amaçla kullanılan cihazlar radar ve uydulardır. Bunlar arasında zaman ve uzay çözünürlüğü en yüksek olan uydu sistemleridir ve bu da onlara önemli bir avantaj sağlamaktadır. Konvektif yapılar için bulut tepe sıcaklığı yağış ile ilişkilendirilebilen anahtar bir parametredir. Buradaki yaklaşım, soğuk tepeli bulutların sıcak tepelilerden daha fazla yağış ürettiklerine dayanmaktadır. Buradan hareketle Arkin, GOES yağış indeksi, ayarlanmış GOES yağış indeksi, Griffith-Woodley, Negri-Adler-Woodley, konvektif-stratiform, güçlendirilmiş konvektif-stratiform, otomatik tahmin edici ve geliştirilmiş otomatik tahmin edici teknikleri gibi ekvator yörüngeli uydu verisini kullanan yöntemler geliştirilmiştir. Tüm bunlar yapılarında doğrusal amprik denklemler içermektedir ve bu denklemlerdeki katsayıların ülkemiz için belirlenmesi zorunluluğu vardır. Buradan hareketle, bu çalışmada 2000 yılı içerisindeki 5-7 Eylül dönemine ait bir konvektif yağışlı olay incelenerek, bir Yapay Sinir Ağı modeli kurulmuştur. Bu model Eylül ayı yağışını gayet iyi tahmin etmiştir. Anahtar Kelimeler: Marmara, yağış, kısa vadeli tahmin, yapay sinir ağları, uzaktan algılama. In order to mitigate with the natural hazards (surface water, floods, etc.) of precipitation origin it is necessary to measure, model and predict the precipitation for water resources and basin management. Due to high spatial and temporal variability of precipitation measurement networks, there are difficulties in determining small scale intensive rainfall events. Currently available weather prediction models yield reliable results, but they cannot catch the spatio-temporal patterns of convective rainfall events. For this reason, the satellite based meteorological information is used as input in weather prediction models. One of the most significant subjects in meteorology domain is the determination of precipitation pattern types and quantities through remote sensing. The instruments used for this purpose are radars and satellites. Satellite systems have the most refined resolution among all these instruments, which provide them significant superiority. For convective structures the cloud top temperature is a key parameter that can be related to precipitation. The basic idea herein is that the cold cloud top temperatures generate more precipitation than hot or warm cloud top temperatures. Keeping this point in mind, first currently available techniques in the literature are explained in detail including Arkin, GOES precipitation index, adjusted GOES precipitation index, Griffith-Woodley, Negri-Adler-Wooley, convective-stratiform, enhanced convective-stratiform, automatic estimator, and advanced automatic estimator techniques. They include empirical equations in their structure and the parameters of these equations must be determined for our country. On the other hand, these methods include linear relationships. In this paper, one convective precipitation event in 2000 is examined each within time period as 5-7 September. These are explained by considering Meteosat 7 infrared channel data for 6-hour total rainfall amounts in such a manner that the data at the upper troposphere vertical levels are transferred to grid points from NCEP/NCAR. The application of the methodology is presented for 26 Marmara region raingauge stations. On the other hand, as effective methodology Artificial Neural Network (ANN) is used and, it has the analogy such that the inputs are taken from the environment through the neurons and transmitted to the brain. ANNs can be thought as a black box model, which processes inputs and produces convenient outputs for inputs. As a first stage this black box is trained and after training system reaches level of decision for inputs. ANNs have ability of learning, due to their training stages. This is feature that there is not available in any classical method. The ANN model can learn by training similar to a human and it has a non-linear structure. Such a non-linearity provides a distinctive possibility in the domain of artificial intelligence. For the model ANN and its analysis, various statistical criteria are used as detection probability (POD), bias, wrong alarm ratio (FAR), critical success index (CSI), target ratio (HR), and transferring of grid points to station points by using a method called inverse distance square. These statistical criteria are explained in this paper. By following the methodology explained above, as a result of ANN properties, convenient architecture for total precipitation amount prediction is proposed that constitutes single input, hidden and output layers with 37, 19 and 1 neurons, respectively. Furthermore, this model is used for precipitation prediction by considering each within time period as 5-7 September. The correlation value of ANN model is 0.89 in testing. Moreover, statistical values are calculated as POD = 0.61, FAR = 0.30, CSI = 0.49, BIAS = 0.86 and HR = 0.77. For this period, rainy events are predicted with success. As it is seen from the descriptions and application results, the cloud top temperature is more related to precipitation by considering low level data of troposphere. Under the light of the proposed prediction model this is the result of key parameter, which reflects the cloud top temperature significant relationship to precipitation. Although other parameters have also significance to lesser degrees the final prediction model take into consideration few of the input variables. In the mean time different combinations of the prediction are investigated throughout the study. Keywords: Marmara, precipitation, short range, prediction, artificial neural network, remote sensing.
Preparation and characterization of polyurethane-hectorite nanocomposites
Get PDFBu çalışmada polimerler içerisinde üretim hacmi sürekli artan bir polimer olan poliüretan ve Türkiye’nin yerli kaynaklarından elde edilen doğal hektorit kili kullanılarak poliüretan nanokom-pozitleri hazırlanmıştır. Kimyasal ve mineralojik analizleri yapılan doğal hektorit kili saflaştırma işlemi yapılmadan ve herhangi bir organik yüzey aktif maddeyle modifiye edilmeden kullanılmıştır. Polimer nanokompozitlerin yapıları, X-ışınları kırınımı ve Fourier transform infrared spektroskopisi kullanılarak aydınlatılmıştır. Yapılan deneyler sonucunda hazırlanmış nanokompozitlerin çok başarılı şekilde hazırlandıkları X-ışınları kırınım yöntemiyle tespit edilmiştir. Fourier transform infrared sprektroskopisiyle de poliüretanın killere moleküler seviyede etkileşmesi sonucunda poliüretanın yapısının değiştiği ve kilin polimer yapısına çok iyi şekilde katıldığı tespit edilmiştir. Nanokompozitlerin ara yüzeyinin morfolojik özellikleri taramalı elektron mikroskobuyla incelenmiştir. Polimer nanokompozitindeki killerin tamamen delamine olmuş yapılarını gözlemlemek için geçirimli elektron mikroskobu kullanılmıştır. Yapılan çalışma sırasında geçirimli elektron mikroskobunda inceleme yapabilmek için çok yeni bir numune hazırlama yöntemi geliştirilmiştir. Nanokompozitlerin ısıl özellikleri ısıl ağırlık analizi ile karakterize edilmiştir. Hazırlanmış olan nanokompozitlerin viskoelastik özelliklerini ve mekanik özelliklerdeki sıcaklığa bağlı değişimini gözlemlemek için dinamik mekanik analiz çalışmaları yapılmıştır. Polimerin hidrofilik özelliğinin belirlenmesi için su temas açısı test yöntemi kullanılmıştır. Nanokompozitlerin çekme-uzama mukavemetlerini belirlemek için mekanik testler yapılmıştır. Yapılan çalışmalar sonucunda çok iyi delamine olmuş nanokompozit yapılar elde edilmiştir ve bunun da neticesinde poliüretanın mekanik özellikleri iyileştirilmiş ve ısıl kararlığı arttırılmıştır. Anahtar Kelimeler: Poliüretan, nanokompozit, kil, hektorit, mekanik özellikler, ısıl kararlılık. Polyurethanes are unique polymeric materials in terms of various applications such as biomedical, coatings, adhesives, thermoplastic elastomers and composite. Polyurethanes have a copolymer structure synthesized with the isocyanates and polyols forming the hard domains and soft domains as a consequence of the isocyanates and polyol part, respectively. The properties of the polyurethanes can be adjusted by two main routes. The first method is the chemical route changing the isocyanate/polyol ratio and using different amounts of chain extender. The second method is the materials route altering the properties of the polyurethanes with different fillers. The versatile types of these two main reactants (isocyanates and polyols), different ways to synthesize the polymer and finally the processing of the polymer change the structure and the properties of the polymer. The properties of the polyurethanes can be improved by using reinforcing material such as talc, mica and glass fiber in the form of polymer matrix composite material. The polymer composites prepared with glass fibers have been used since 1950s. They have been applied in the industrial scale as well. These materials increase the tensile strength and improve the mechanical properties but they sacrifice the elongation at break. Currently new composite materials are based on the reinforcing agents at the nano-scale enabling the increase in strength without loss in the elasticity of the material and even getting more tough materials. There are two other advantages of nanocomposites. The one is the increase of thermal properties and the other one is better optical properties. Within this context clays form important family of nano fillers. The clays used in the preparation of polymer nanocomposites are generally from the smectite family with well ordered crystalline structure. Clay mineral is abundant in nature. It is a very cheap raw material for preparation of industrial product, if it is used without any modification and purification. The clays can be found in the polymer matrix in three forms such as intercalated, flocculated or exfoliated structure. The best structure is the exfoliated structure due to the best dispersion of clay can be obtained in the polymer matrix and level of utilization for the reinforcement is maximum. In this work, we have improved the properties of the polyurethanes with the materials route using the clays as the nano-scale reinforcing agent. In previous studies, the montmorillonite clay has always been examined to reinforce the polyurethane polymer. No work has been reported using the clay hectorite. In this work, we have investigated the effect of the hectorite content on the properties of the polyurethane. In some polymers such as polyethylene and starch, it has been observed that hectorite improves the mechanical properties of the matrix polymer. These led us to use the hectorite in the polyurethane matrix forming very novel nanocomposites. In this study, very novel polyurethane nanocomposites were prepared with the natural nanoclay hectorite without purification and organical modification. Generally, in the preparation of the polymer-clay nanocomposites, the organically modified clays have been used to create partial delamination before interacting with the polymer. In this study the exfoliated structures could be obtained without organic modification of the clays because of the hydrophilic nature of the polyurethane and swelling capacity of hectorite in the solvent, dimethylformamide. Exfoliated structures were identified using the X-ray diffraction analysis. Moreover the scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to support the findings of the X-ray analysis. A novel sample preparation for transmission electron microscopy technique was used. With SEM, the clay particles could not be observed which shows the good dispersion of the clay platelets. With TEM, the individual layers of clay which could not be seen with SEM, were easily investigated with the thickness given in the pictures. Fourier infrared spectroscopy was used to determine the interactions at the molecular level. It was determined that the polyurethane and the clay interacted at the molecular level changing the structure of the polyurethane. Mechanical testing and thermal gravimetric tests were done for further investigations of the material. As a result of this successful nanocomposite preparation, the mechanical properties increased 113 wt % and thermal properties were also improved. Keywords: Polyurethane, nanocomposite, clay, hectorite, mechanical testing, thermal stability.
Termoakustik soğutucu analizi
Get PDFAcoustic waves consist of pressure, displacement and temperature oscillations as a response to the pressure variations. The interaction of these effects in gas close to a solid surface generates thermoacoustic oscillations. At the solid surface heat can be extracted or supplied to the gas. The result of this interaction is that acoustic work is absorbed in order to transport heat, generating a temperature gradient along the solid surface. While in the reverse case a sound wave is sustained in case of a large temperature gradient along the solid surface. Utilizing this effect, heat can be transferred from a low temperature source to a high temperature source by a thermoacoustic refrigerator, while the opposite process can be achieved by a thermoacoustic prime mover which converts heat applied on solid surface to acoustical work. Thermoacoustic effects have attracted the scientist's attention for over two centuries. But a quantitatively accurate understanding was not achieved until Rott's (1969) studies, which has been confirmed experimentally by Yazaki et al (1979). Many thermoacoustic engines have been constructed and analyzed till now with an increasing interest. One reason for the increasing interest in thermoacoustics is from its potentiality of environment protection. Conventional refrigerators with freon gas as their working fluid are being prohibited because of its destruction of ozone layer. But the thermoacoustic engines do not use any harmful working fluid. They use mainly helium, or helium with argon, neon, xenon or such inert gaseous. The other reason is that conventional systems have moving parts, so they are less reliable and more expensive than thermoacoustic devices. Because thermoacoustic devices use no moving parts, no close tolerances, no exotic materials, the interests on thermoacoustic engines have increased a lot. In this study a thermoacoustic cooler working with atmospheric air was designed and constructed. A systematical approach was followed to design the device which had been proposed by Tijani. The system was constructed with a speaker as the acoustical source, resonator, stacks at different lengths, stack holder, signal generator, amplifier, temperature and pressure measurement system. After constructing the thermoacoustic device, pressure distributions in the resonator at various resonance frequencies were examined. The resonance frequencies of the system were approximately measured at 112 Hz, 180 Hz and 300 Hz starting from the first harmonics. The theoretical and experimental pressure distributions were compared. Changes of pressure antinode position with respect to acoustical source amplitude at resonance frequencies were studied theoretically and experimentally. The analytical and experimental results were compared. Three stacks at different lengths were constructed. After that the temperature distributions on the stack at different stack positions were examined and compared to the theoretical results with and without taking care of axial conduction effects. The maximum temperature difference, measured between the tips of the stacks are 20.4oC (10 cm length stack), 21.4oC (15 cm length stack), 27.6oC (22 cm length stack). It was concluded that the axial conduction effects are important in a system at low power. It was also measured the steady state temperature distribution on stack, and it was seen that it was linear as it should be. Later it was examined how the existence and the position of the stack affects the pressure distribution and the resonance frequency of the system. It was concluded that the existence and the position of the stack in the resonator affects the resonance frequency and pressure antinode position. In the experiments, it was measured that the resonance frequency of the system was changed between 108 Hz and 112 Hz depending on the stack position while the resonance frequency of the empty resonator is 112 Hz. Despite the fact that pressure antinode position from open end of the resonator was measured 72 cm at empty resonator resonance frequency, it was observed that the pressure antinode position decreased down to 66 cm as a result of the stack inside the resonator. At the end it was examined how slight frequency changes affects the system performance. It was measured that a few Hertz frequency changes does not affect the system performance a lot, but there is a sharp decrease at the system performance if the frequency changes are larger than a few Hertz. Keywords: Thermoacoustics, thermoacoustic cooler, thermoacoustic engine.Ses dalgaları içerisindeki basınç salınımları ile birlikte gerçekleşen sıcaklık salınımları sonucu akışkan ve akışkana temas eden katı yüzey arasındaki ısıl etkileşimler termoakustik olarak adlandırılır. Termoakustik sistemlerin maliyetlerinin düşük, yapılarının basit olması, atmosfere zarar veren gazlar kullanmaması, hareketli parçalarının bulunmaması gibi sebeplerle, klasik soğutma sistemlerine göre pratikteki verimlerinin düşük olmalarına rağmen üzerlerindeki ilgi artarak devam etmiştir. Termoakustik soğutucular geleceğin soğutma teknolojilerinden birisi olmaya adaydır. Bu çalışmada atmosferik hava ile çalışan basit bir termoakustik soğutucu dizayn ve inşa edilmiş, daha sonra sistem üzerinde çeşitli inceleme ve analizler yapılmıştır. Sistemin rezonans frekansları birinci harmonikten itibaren yaklaşık olarak 112 Hz, 180 Hz, 300 Hz olarak ölçülmüştür. Akustik kaynak olarak bir hoparlör kullanıldığından ideal rezonans tüpünden farklı olarak kapalı uçta hız nodunun oluşmadığı görülmüştür. Daha sonra sistemdeki basınç dağılımının şeklinin akustik kaynak genliğine bağlı olarak değişimi incelenmiştir. Ardından üç farklı uzunlukta yığın kullanılarak farklı yığın pozisyonlarında yığın üzerindeki sıcaklık dağılımları ve yığın uçları arasındaki sıcaklık farkları ölçülmüş ve teoriyle karşılaştırılmıştır. Yığınların her iki ucu arasında en yüksek 27.6oC sıcaklık farkı ölçülmüştür. Daha sonra rezonans tüpü içerisinde yığının varlığının ve pozisyonunun sistemin basınç dağılımı ve rezonans frekansı üzerine etkileri incelenmiştir. Yığının sistem içindeki varlığının ve pozisyonunun sistem çalışma frekansını ve basınç antinod pozisyonunu etkilediği gözlenmiştir. Son olarak sistemin çalışma frekansındaki kaymaların sistem performansı üzerine etkileri incelenmiştir. Anahtar Kelimeler: Termoakustik, termoakustik soğutucu, termoakustik makine. 
Bir uçağın yatış açısı kontrolü için farklı tip denetleyici karşılaştırmaları
Get PDFBasic automatic control system consists of controller, actuator, sensor and plant. In a closed loop control system, the difference between the input and feedback is fed to the controller so as to reduce the error and bring the output of the system to a desired value. The actuator is a power device that produces the input to the plant according to the control signal so that the output will approach the reference input. The sensor converts the output variable into another suitable variable. An advantage of this system is the fact that the use of feedback makes the system response relatively insensitive to external disturbances and internal variations. The aim of the controller of the closed loop control systems is to produce an output following the input. P, PD, PI and PID controllers are widely used for this aim with some variations according to the system structure. These controllers have advantages and disadvantages. P type controller's main advantage is its simplicity. The advantage is I controller is that the output is proportional to the accumulated error. Thus, error can be eliminated by using it. The advantage is D controller is that the controller will provide large connections before the error becomes large. P type controller's main disadvantage is that there may be fix steady state error. The disadvantage is I controller is that the system less stable if adding the pole at the origin. The disadvantage is D controller is that if the error is constant it will not produce a control output. While designing the control system with classical controllers, the root locus technique allows the designer to examine the movement of the closed loop poles of the control system as a function design variables. Classical controller is based on mathematical model. In many cases, the mathematical model of the control process may not exist, or may be too "expensive" in terms of computer processing power and memory, and a system based on empirical rules may be more effective. If the model is known less, or not got, the control reaction is not produced. In this situation, the fuzzy logic, neural network and genetic algorithm based on developing controller algorithms are also used. The fuzzy logic controllers can be used for this aim, for which the membership functions and the choice of the rules are essential. A fuzzy control system is a control system based on fuzzy logic. A mathematical system that analyzes analog input values in terms of logical variables that take on continuous values between 0 and 1, in contrast to classical or digital logic, which operates on discrete values of either 0 and 1 (true and false). The input variables in a fuzzy control system are in general mapped into by sets of membership functions similar to this, known as "fuzzy sets". The process of converting a crisp input value to a fuzzy value is called "fuzzification". Given "mappings" of input variables into membership functions and truth values, the microcontroller then makes decisions for what action to take based on a set of "rules". Rules can be solved in parallel in hardware, or sequentially in software. The results of all the rules that have fired are "defuzzified" to a crisp value by one of several methods. Although genetic algorithms and neural networks can perform just as well as fuzzy logic in many cases, fuzzy logic has the advantage that the solution to the problem can be cast in terms that human operators can understand, so that their experience can be used in the design of the controller. This makes it easier to mechanize tasks that are already successfully performed by humans. In this study, the comparison of the P, PD, PI and fuzzy controllers are realized by utilizing the roll control system of an airplane. The system is composed of a comparator, actuator and aircraft equation of motion. Sensor is considered to be perfect device and represented as a unity feedback. The P type controller is designed from root locus plot at the crossover point. The PD type controller is get from desired stability errors using time domain. The PI type controller is designed using Routh-Hurwitz stability criterion. In classical controllers, the outputs having the preferred performance can be obtained by adjusting the gain; whereas, for the fuzzy controllers better values can be obtained by increasing the number of input and output functions and the number of the rules. Keywords: Automatic flight control, traditional controllers, fuzzy controllers. Kapalı çevrim kontrol sistemleri, kontrol edilen çıkış değişkeninin ölçülüp geri beslenerek arzu edilen giriş değişkeni ile karşılaştırıldığı sistemlerdir. Sistemin çıkışı, arzu edilen çıkış değerini sağlayacak biçimde giriş büyüklüğü ile ayarlanır. Negatif geri beslemede daima giriş ile çıkışın bir farkı alınır. Kontrol elemanına bir hata girişi olarak iletilen bu fark, çıkışın istenilen değere getirilmesini ve bu değerde sabit tutulmasını sağlar. Kapalı çevrim kontrol sistemlerinde denetleyicinin amacı, hata değerinin yapısına ve kendi denetim etkisine bağlı olarak uygun bir kumanda denetim sinyali üretmektir. Sistem yapısına bağlı olarak bir takım ayarlamalar ile P, PI, PD ve PID denetleyiciler, bu amaçla sıklıkla kullanılan geleneksel denetleyicilerdir. Klasik denetleyicilerin yetersiz kaldığı durumlarda, bulanık denetleyiciler de bu amaçla kullanılabilir olup, burada da üyelik fonksiyonları ve kuralların seçimi önem kazanmaktadır. Bu çalışmada, bir uçağın uçuş kontrol sisteminde önem arzeden yatış açısı kontrolü için klasik denetleyicilerden P, PD, PI tip denetleyiciler ile küme ve kuralları deneme yoluyla oluşturulmuş bulanık denetleyicinin karşılaştırmaları yapılmaktadır. Klasik denetleyicilerde kazanç ayarlamalarıyla, bulanık denetleyicide ise üyelik fonksiyonlarının ve kurallarının seçilmesi ile elde edilen çıktılar karşılaştırıldıklarında, eğer yatışkın duruma daha çabuk ulaşılmak isteniyor ve belli bir kararlılık hata tolerans değeri söz konusuysa P veya PD denetleyicili sistem, yatışkın duruma gelme zamanından daha çok kararlılık hatası değerinin minimum olması hedefse PI denetleyicili sistem ya da bunların kesişimi şeklinde bir çözüm aranıyorsa bulanık denetleyicili sistem kullanım yoluna gidilebilir sonucuna ulaşılmıştır. Anahtar Kelimeler: Otomatik uçuş kontrol, klasik denetleyiciler, bulanık denetleyiciler. 
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