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Access status: Metadata only ,
FLEXURAL-TORSIONAL COUPLED VIBRATION ANALYSIS OF A THIN-WALLED CLOSED SECTION COMPOSITE TIMOSHENKO BEAM BY USING THE DIFFERENTIAL TRANSFORM METHOD
(Springer Netherlands, 2006-01-01) Kaya, Metin Orhan; Özdemir, Özge
In this study, a new mathematical technique called the Differential Transform Method (DTM) is introduced to analyse the free undamped vibration of an axially loaded, thin-walled closed section composite Timoshenko beam including material coupling between the bending and torsional modes of deformation, which is usually present in laminated composite beams due to ply orientation. The partial differential equations of motion are derived applying the Hamilton's principle and solved using DTM. Natural frequencies are calculated, related graphics and the mode shapes are plotted.
Access status: Open Access ,
Creation, application and analysis of choreography in choral performance, with a proposed notation system
(Graduate School, 2025-06-12) Kuntman, Ayşegül, Begüm; Gül, Recep; 409211216; Music Theory and Composition
This thesis explores the integration of choreography into choral performances, framing concerts as multi-sensory experiences that engage both auditory and visual perception. The core objective of the study is to explore choreography creation processes and to analyze how movement is used as a tool to enhance musical expression and narrative design. The methodology combines ethnographic fieldwork including participant observation and conversations with fellow singers, developing a movement notation system for musicians' use and analyses of scores and videos. The literature review contains historical and perceptual connections between music and movement, movement in choral history, existing movement notation systems and movement classifications. Field research draws from the author's personal experience as a choral performer and a composer. This section explores the choreography creation processes and the reasoning behind them. This section exhibits that the creation process is usually a collaborative one and most of the time it happens close to the concert. The source of inspiration for creation is usually the lyrics or cultural connotations, sometimes other performances. Recognizing a gap in standardized movement notation systems tailored for musicians, the study introduces a newly developed notation system. This notation system encompasses hands, arms, body direction, steps, and spatial formations. This innovation is both a creative and analytical tool, aiming to document and communicate choreographic elements in a structured way. In the analysis section, selected performances are examined using the proposed system. On top of the hand, step and body direction movements, movement in space, movement of soloists and cultural influence on movement are also presented and the expressive potential of choreographed elements are discussed. The analysis revealed consistent correlations between musical and physical gestures in choral performances. Movements often reflect musical qualities - legato lines are matched with smooth, continuous motion, while slow arm raises frequently accompany glissandos, crescendos, or ascending melodic lines. Rhythmic patterns are visually emphasized through swaying or stepping, which can also introduce new rhythmic layers or reframe subdivisions. Movement phrases tend to mirror musical phrases, and choreographic tools like soloist isolation, formation changes, and gesture cues signal structural or expressive shifts. Repeated musical material is sometimes varied visually through choreographic additions, while contrapuntal movement can parallel musical polyphony. Spatial orientation is used dynamically - choirs face the audience during forte passages and turn away or shift position for softer dynamics, especially at conclusions. Strategic stillness, gesture-based cadential emphasis, and narrative or literal movements further enrich the performance. Cultural context also shapes choreography; various choirs incorporate regional dance elements into their movement language, enhancing both visual identity and interpretive depth. These culturally rooted gestures, drawn from folk or traditional forms, contribute to a more immersive and resonant concert experience. The conclusion highlights the study's contributions to choral composition and performance practices, emphasizing the importance of codifying movement not as a restrictive framework but as a means to enhance artistic expression. It also outlines possible directions for further research, such as broader audience studies and implementation of the system in varied choral repertoires.
Access status: Metadata only ,
Turkey's rurality: A comparative analysis at the EU-level
(Faculteit der Economische Wetenschappen en Bedrijfskunde, 2006-01-01) Peter Nijkamp; Tuzin Baycan Levent; Aliye Ahu Gulumser
The future of Europe's rural peripheries as well as the future of rural societies is one of the most important development and planning issues of the EU. Several typologies of rural areas and different rural development indicators have been developed by researchers and international organizations such as OECD and EU to better understand the dynamics of rural areas and to develop relevant policies for these areas. The typologies of rural areas are based on sub-national territories and administrative or statistical units (i.e. local, regional, NUTS3, NUTS5), whereas rural development indicators include a wide range of indicators from population and migration to economic structure and performance and from social well-being and equity to environment and sustainability. Against this background, the aim of this paper is to compare and evaluate Turkey's rurality with the EU-25 countries on the basis of rural development indicators. The data and information used for comparison and evaluation are based on EUROSTAT data. A multicriteria analysis technique, factor analysis is deployed to define Turkey's rurality in the European context. To map out the characteristics and dynamics of Turkey's rurality may also help to develop relevant policies for rural development of the country.
Access status: Open Access ,
Yolindi (Biga, Çanakkale) Fe-Cu skarn cevherleşmesinin evrimi: Mineralojik, jeokimyasal ve izotopik yaklaşımlar
(Lisansüstü Eğitim Enstitüsü, 2023-12-01) Kaya, Mustafa; Kumral, Mustafa; Khalil, Amr Abdelnassar Ali; 505202303; Jeoloji Mühendisliği
Yolindi bölgesinde Şaroluk granitoyidi ile ilgili daha önce de jeolojik ve petrolojik araştırmalar yapılmıştır. Ancak, Şaroluk granitoyid sokulumunun cevher oluşturma potansiyeline yönelik yapılmış bir çalışma bulunmamaktadır. Bu çalışmayla bölgedeki skarn cevherleşmesi keşfedilerek, prograd evreden retrograd alterasyonlara kadar skarn evriminin aşamaları incelenmekte ve bulgular daha geniş bir jeolojik, mineralojik ve jeokimyasal çerçeve içinde değerlendirilmektedir. Ayrıca yapılan çalışma, Yolindi cevherleşmesinin evrimsel geçmişini bir ada-yayı ortamındaki kalkalkalin magmatik aktivite ile ilişkili olarak değerlendirmekte ve mineral bileşimlerini ve oluşumunu diğer küresel ve bölgesel Fe-Cu skarn yatakları ile karşılaştırmaktadır. Biga Yarımadası'ndaki Yolindi Fe-Cu skarn yatağı, Şaroluk kuvars monzonit sokulumunun fillit, şist, hornfels, mermer içeren Paleozoyik yaşlı Torasan Formasyonu kayaçlarına intrüzyonu ile oluşmuştur. Skarnlaşma sırasında Şaroluk kuvars monzonit sokulumundan gelen magmatik akışkanlar ile Torasan Formasyonu arasındaki reaksiyonlar demir (Fe) ve bakır (Cu) gibi metallerle ilişkili skarn mineralleri meydana getirmiştir. Başlangıçta bu reaksiyonlar, magnetit ve pirit içeren ojit bakımından zengin piroksenler ve andradit garnet gibi prograd skarn mineralleri oluşturmuştur. Sistem soğudukça, bu ilk mineraller retrograd alterasyona uğrayarak epidot, aktinolit ve klorit gibi minerallerin yanı sıra kalkopirit, bornit, ikincil manyetit ve speküler hematit gibi diğer bakır ve demir minerallerinin oluşumuna yol açmıştır. Skarn oluşumu, Torasan Formasyonu ile temas halindeki Şaroluk granitoid intrüzyonu çevresinde konsantrik ve kontak-metamorfik alterasyon modellerini gösteren farklı mineral toplulukları ile endoskarn ve egzoskarn evrelerine (proksimal, intermediate ve distal zonlar) ayrılmaktadır. Kükürt δ34S izotop değerleri endoskarn zonda +0,57 ‰ VCDT pozitif değerlerinden başlayıp, dış zonlara doğru proksimal ve intermediate ekzoskarn zonda -9,44 ‰ VCDT negatif değerlere kadar ulaşmaktadır. Bu değerler, magmatik, sedimanter ve muhtemelen organik madde dahil olmak üzere çok çeşitli kükürt kaynağına işaret etmektedir. Özellikle endoskarn zonda hidrotermal akışkanların δ34S değerleri magmatik-hidrotermal bir kökene işaret etmektedir. Endoskarn ve proksimal bölge hidrotermal akışkanları hafif bir negatif özellik gösterirken, intermediate bölgede ise hidrotermal akışkanların organik açıdan zengin kaynaklardan ve/veya metamorfik sülfür kaynaklarından güçlü şekilde etkilendiği görülmektedir. Kalsitin karbon ve oksijen izotopik bileşimleri (δ13C ve δ18O), mermer örneklerindeki denizel karbonat özelliklerinden (+1.89 ila +2.23‰ VPDB; +21.61 ila +21.73‰ VSMOW), yüksek sıcaklıktaki magmatik akışkanlar ile mermerin çözünerek dekarbonizasyonun etkilerini yansıtan prograd evrede (-6.0 ila +0.09‰ VPDB; +6.22 ila +18.14‰ VSMOW) ve meteorik su ile karışımın etkilerini gösteren retrograd evrede (-3.8 ila -2.25‰ VPDB; +0.94 ila +3.62‰ VSMOW) azalmış değerlere doğru bir ilerleme göstermektedir. Prograd minerallerdeki sıvı kapanım verilerinden elde edilen yüksek sıcaklıklar (412,20°C'ye kadar) ve tuzluluklar (%26,07 NaCl eşdeğerine kadar), kaynama koşulları altında erken skarn oluşumuna (prograd) işaret etmektedir. Buna karşılık, retrograd evrede gözlenen daha soğuk, seyreltik akışkanların meteorik sularla karışımının arttığını ve ana kayalardaki organik malzemelerle etkileşime girdiğini göstermektedir. Bu da çeşitli kaynak ve süreçleri içeren çok yönlü bir kökene işaret etmektedir. Bu çalışmada, Yolindi bölgesindeki Fe-Cu skarn cevherleşmesinin magmatik, metamorfik ve meteorik akışkanlar arasındaki karmaşık etkileşimlerden kaynaklandığı ve skarn cevherleşmesinin bölgesel metalojenisi için etkileri olan dinamik bir cevher oluşturma ortamını yansıttığı sonucuna varılmıştır. Yolindi Fe-Cu Skarn cevherleşmesinin oluşumunu dört ana aşama etkilemiştir: metamorfik-bimetasomatik, prograd evre, retrograd evre ve ilerleyen süreçte, metasomatizma sonrası bir süperjen evre olan ayrışma ve oksidasyon evresi tanımlanmıştır. Andradit-grossular geçişi gibi mineralojik değişimler, meteorik akışkanların eklenmesine bağlı olarak değişen hidrotermal akışkan bileşimlerini ve özelliklerini yansıtmaktadır. Yolindi Fe-Cu Skarn cevherleşmesinin mineral bileşimleri, Dünya'da bilinen skarn yatakları ve Türkiye'deki skarn yatakları (örneğin, Ayazmant Fe-Cu ve Evciler Cu-Au skarn yatakları) ile uyumludur. Yolindi Fe-Cu Skarn cevherleşmesi, magmatik kökenli cevher içeren akışkanlarla ilişkili olarak ada yayı ortamında gelişmiştir.
Access status: Open Access ,
Real and reactive power optimization by approximate sub-optimum techniques
(Institute of Science and Technology, 1990-11-21) Özdemir, Aydoğan; Özkan, Yılmaz; 14171; Electrical Engineering
Guided by the experience that real power is more sensitive to nodal phase angles and reactive power to voltage magnitudes, a new formulation of power flow op timization is developed which exploits this decoupling and consequently reduces problem size, computer memory and solution time. The decomposition of the variables and the load flow equations results in the formation of two subproblems- one corresponding to the reactive power equations (Q-Optimization) and the other to the real po wer equations (P- Optimization). The two subproblems are alternatively solved until the desired accuracy is at tained. The method has considerable potantiel for real time applications and the solution of only one problem, if desired. Approximate models are preferred for both mod ules. The errors induced by ignored set of power flow equations, which are the major limitations common to all approximate models, are overcome by the proposed formu lations. Q-optimization subproblem is devoted to the minimi zation of the real power transmission losses (RPTL) and the improvement of voltage profiles by adjusting the con trol variables of the module, i.e. generator voltage mag nitudes, VAR injection values of the shunt capacitor/reac tors and tap values of the tap changing transformers, p-optimization module is used to minimize the hourly fuel costs (HFC) of the thermal generating units. It is also possible to eliminate an unfavourable increase in the RPTL throughout the latter module. The proposed formulations are programed and the ef ficiency is tested by solving several test systems. The results are discussed and compared with those reported in the literature.