Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Citation - WoS: 5Citation - Scopus: 5Loop Based Classification of Planar Scissor Linkages(Springer, 2022) Kiper, Gökhan; Korkmaz, Koray; Gür, Şebnem; Yar Uncu, Müjde; Maden, Feray; Akgün, Yenal; Karagöz, CevahirScissor linkages have been used for several applications since ancient Greeks and Romans. In addition to simple scissor linkages with straight rods, linkages with angulated elements have been introduced in the last decades. In the related literature, two methods have been used to design scissor linkages, one of which is based on scissor elements, and the other is based on assembling loops. This study presents a systematic classification of scissor linkages as assemblies of rhombus, kite, dart, parallelogram and anti-parallelogram loops using frieze patterns and long-short diagonal connections. After the loops are replicated along a curve as a pattern, the linkages are obtained by selection of proper common link sections for adjacent loops. The resulting linkages are analyzed for their motions and they are classified as realizing scaling deployable, angular deployable or transformable motion. Some of the linkages obtained are novel. Totally 10 scalable deployable, 1 angular deployable and 8 transformable scissor linkages are listed. Designers in architecture and engineering can use this list of linkages as a library of scissor linkage topologies.Article Citation - WoS: 3Citation - Scopus: 3Çok Fonksiyonlu Form Değiştirebilir Köprü Tasarımı için İki Serbestlikli Strüktürel Mekanizma Önerisi(Gazi Üniversitesi, 2017) Gür, Şebnem; Yar, Müjde; Korkmaz, KorayHareketli köprüler ilk zamanlar korunma ihtiyacı ile tasarlanmıştır. Modern zamanlarda ise ulaşımıkolaylaştırmak için geliştirilmeye devam edilmektedir. Sabit köprülerin aksine farklı kullanım senaryolarınıdesteklemeleri sebebiyle tercih edilmektedirler. Bu yazıda mevcut hareketli köprüler kinematik özellikleriaçısından tanıtılmış, hangi kullanım seneryolarını destekledikleri ve eksik kaldıkları yönler açıklanmıştır.Daha sonra güncel bir örnek olan Rolling Bridge'de kullanılmış strüktürel mekanizmanın tasarım prensiplerden yararlanarak, tüm kullanım senaryolarını destekleyen form değiştirebilen köprü için çokdevreli ve iki serbestlikli yeni bir strüktürel mekanizma önerilmiştir. Son olarak mekanizmanın pozisyonanalizi yapılarak Microsoft Excel® ortamında gerçekleştirilen grafik sunulmuşturArticle Citation - WoS: 6Citation - Scopus: 5Design of Anti-Parallelogram Loop Assemblies(Int. Association for Shell and Spatial Structures, 2019) Gür, Şebnem; Korkmaz, Koray; Kiper, GökhanScissor mechanisms are frequently used for deployable structures and many studies have been conducted on the subject. Most of the studies consider scissor units as modules in the design process. An alternative approach is to utilize loops as the modules for design. In this paper, the design alternatives of single degree-of-freedom planar linkages comprising anti-parallelogram loops using the loop assembly method is presented. First, scissor mechanisms are reviewed. Next, the types of four-bar loops and the resulting linkages in the literature are introduced and those which are yet to be explored, anti-parallelogram being one of them, are identified. Then the loop assembly method and the examples in the literature are reviewed. As a method to form as many alternatives as possible, symmetry operations are proposed. Suitable frieze symmetry groups utilized for obtaining the assemblies are explained and the anti-parallelogram loop patterns are derived. Next, the single degree-of-freedom linkages are obtained from the loop assemblies. Finally, a selection of the resulting linkages with novel properties are presented. This study shows that loop assemblies are efficient in systematic type synthesis of scissor linkages, some types of which could not be foreseen by using units as modules.Conference Object Citation - WoS: 1Citation - Scopus: 2Synthesis of Scalable Planar Scissor Linkages With Anti-Parallelogram Loops(Springer Verlag, 2019) Gür, Şebnem; Karagöz, Cevahir; Kiper, Gökhan; Korkmaz, KorayScissor linkages are commonly used as mechanisms for scaling objects. They constitute a significant portion of deployable structures. Since 1960s many researchers sought to form novel structures using the scissor units. In 1990s Hoberman brought a new perspective to the field when he used the loops, not the units to form linkages. Starting from mid 2000s, other researchers joined into this new approach of design. One of the latest researches presented a design for scaling a circular forms with anti-parallelogram loops. This study shows that an anti-parallelogram loop assembly can also be used for scaling planar curves with variable curvature.Article Citation - WoS: 8Citation - Scopus: 7A New Approach To the Generation of Retractable Plate Structures Based on One-Uniform Tessellations(The American Society of Mechanical Engineers(ASME), 2017) Gazi Gezgin, Aylin; Korkmaz, KorayRetractable plate structure (RPS) is a family of structures that is a set of cover plates connected by revolute joints. There exists wide range of possibilities related with these structures in architecture. Configuring the suitable shape of rigid plates that are able to be enclosed without any gaps or overlaps in both closed and open configurations and eliminating the possibility of contact between the plates during the deployment have been the most important issues in RPS design process. Many researchers have tried to find the most suitable shape by using kinematical or empirical analysis so far. This study presents a novel approach to find the suitable shape of the plates and their assembly order without any kinematical or empirical analysis. This approach is benefited from the one-uniform mathematical tessellation technique that gives the possibilities of tiling a plate using regular polygons without any gaps or overlaps. In the light of this technique, the shape of the plates is determined as regular polygons and two conditions are introduced to form RPS in which regular polygonal plates are connected by only revolute joints. It should be noted that these plates are not allowed to become overlapped during deployment and form gaps in closed configuration. Additionally, this study aims to reach a single degreeof- freedom (DoF) RPS. It presents a systematic method to convert multi-DoF RPS into single DoF RPS by using the similarity between graph theory and the duality of tessellation.Article Citation - WoS: 5Citation - Scopus: 9The Effect of Architectural Form on the Earthquake Behavior of Symmetric Rc Frame Systems(Techno Press, 2014) İnan, Tuğba; Korkmaz, Koray; Çağatay, İsmail HakkıIn this study, structural irregularities in plan, which has a considerable effect on earthquake behavior of buildings, have been investigated in detail based on Turkish Earthquake Code 2007. The study consists of six main parametric models and a total of 144 sub-models that are grouped based on RC structural systems such as frame, frame + rigid core, frame with shear wall, and frame with shear wall + rigid core. All models are designed to have both symmetrical plan geometry and regular rigidity distribution. Changes in the earthquake behavior of buildings were evaluated according to the number of storeys, number of axes and the configuration of structural elements. Many findings are obtained and assessed as a result of the analysis for each structural irregularity. The study shows that structural irregularities can be observed in completely symmetric buildings in terms of plan geometry and rigidity distribution.Article Citation - WoS: 11Citation - Scopus: 11An Investigation on Plan Geometries of Rc Buildings: With or Without Projections in Plan(Techno Press, 2012) İnan, Tuğba; Korkmaz, Koray; Çağatay, İsmail HakkıThe interaction of plan geometry and structural configuration, a determinative factor in the earthquake behavior of buildings, has become a serious issue in the building industry in Turkey due to the poor seismic performance of R/C buildings during the latest earthquake. Consequently, designing new buildings without structural irregularities against earthquake loads is proving to be more significant. This study focuses on the effects of plan geometries on earthquake performances of buildings. In that respect, structural irregularities in the plan are investigated in detail based on the Turkish Earthquake Code (TEC 2007). The study is based on five main parametric models and a total of 40 sub-models that are grouped according to their plan geometries with excessive projections such as L-shaped, H-shaped, T-shaped and U-shaped models. In addition to these, a square model without any projections is also generated. All models are designed to have the same storey gross area but with different number of storeys. Changes in the earthquake behavior of buildings were evaluated according to the number of storeys, the projection ratios and the symmetry conditions of each model. The analysis of each structural irregularity resulted in many findings, which were then assessed. The study demonstrates that the square model delivers the best earthquake performance owing to its regular plan geometry.Article Citation - Scopus: 11A Novel Planar Scissor Structure Transforming Between Concave and Convex Configurations(WITPress, 2017) Yar, Müjde; Korkmaz, Koray; Kiper, Gökhan; Maden, Feray; Akgün, Yenal; Aktaş, EnginIn this paper, a novel two-dimensional scissor structure that transforms between concave and convex configurations is presented. The structure is designed by a method of assembling kite or anti-kite loops in the flat configuration. Angulated units are generated from the assembled loops. Finally, a new angulated scissor unit is introduced in order to design the novel scissor structure.Article Citation - Scopus: 9Design Alternatives of Network of Altmann Linkages(WITPress, 2017) Atarer, Fulya; Korkmaz, Koray; Kiper, GökhanThis paper presents a method of building deployable network assemblies derived from the single degree of freedom (DoF) over constrained Altmann linkage as a basic module. The method is based on assembling linkages with common links and joints or overlapping with extra R or 2R joints. New loops are emerged with overlapping method. The networks created have a single DoF, are over-constrained and have both fully deployed and folded configurations. The computer-aided models (CAD) are used to demonstrate these derived novel mechanisms.Article Citation - WoS: 54Citation - Scopus: 59An Approach for Developing Sensitive Design Parameter Guidelines To Reduce the Energy Requirements of Low-Rise Apartment Buildings(Elsevier Ltd., 2012) Yıldız, Yusuf; Korkmaz, Koray; Göksal Özbalta, Türkan; Durmuş Arsan, ZeynepHigh levels of energy consumption in residential buildings and global warming are important issues. Thus the energy performance of buildings should be improved in the early stages of design. This article describes an approach for developing guidelines on sensitive and robust design parameters for the present, the 2020s, the 2050s and the 2080s. Such guidelines can help architects to design low-rise apartment buildings that require less energy for various purposes, such as heating or cooling. The article consists of a general literature review, interviews with architects, the generation of case-specific information and a mock-up presentation and a meeting with professionals. An example guideline that aims to reduce annual cooling energy loads under global warming in low-rise apartment buildings located in hot-humid climates is presented to demonstrate how the proposed approach can be applied. For this guideline, case-specific information was generated, and a global sensitivity analysis based on Monte Carlo Analysis and the Latin Hypercube Sampling technique was performed. The results show that the suggested approach is feasible and could be used to provide helpful information to architects during the design of low-rise apartment buildings with high energy performance. The most sensitive design parameters that affect annual cooling energy loads in low-rise apartment buildings were natural ventilation, window area, and the solar heat-gain coefficient (SHGC) of the glazing. The results are relevant for the present, the 2020s, the 2050s and the 2080s.