Browsing by Author "Dursun, Onur"

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A novel framework to evaluate the performance of responsive kinetic shading devices
(LLC Editorial of Journal "Light Technik" lights-nr@inbox.ru VNISI rooms 327334106 Prospect Mira Moscow 129626, 2019) Mustafa Teksoy; Onur Dursun; Teksoy, Mustafa; Dursun, Onur
Determining control parameters of kinetic shading devices introduces a dynamic problem to designers which can best be tackled by computational tools. Yet excessive computational cost inherits in reaching near optimum solutions led to exclusion of many design alternatives and weather conditions. Addressing the issue the current study aims to explore the design space adequately and evaluate the performance of responsive-kinetic shading devices (RKSD) by proposing a novel framework. Current framework adopts a surrogate-based technique for multi-objective optimization of control parameters of a RKSD on randomly sampled daylight hours. To test the plausibility of any results obtained by the proposed framework a controlled experiment is designed. Empirical evidences suggest RKSD outperforms the static one in daylighting and view performance metrics. However considering indoor temperature no significant differences observed. © 2020 Elsevier B.V. All rights reserved.
An Investigation into Fenestration Strategies on Building Performance: Case of Residential Buildings in Turkey
(2018) Ünlü, Nezahat Püren; Dursun, Onur
The reduction of energy consumption is a major challenge around the world. Using natural daylight is one of the basic energy saving criteria which promotes usage of natural sources as well as decreases energy demand dramatically in residential buildings. However, the insufficient study of fenestration strategies through building design significantly limits the impact on daylight such building performance. To this end, the current study aims to investigate the impact of optimum fenestration strategies on building performance in the context of residential buildings in Turkey. Two performance metrics, namely energy use intensity (EUI) and useful daylight illuminance (UDI), were employed through analysis. In the first part of the study, a hypothetical test box model was considered to determine optimum fenestration strategies in four different climate zones of Turkey. In this context, fenestration ratios at each elevation formed the decision variables while HyPE optimization algorithm attempted to find solutions that minimize EUI and maximizes UDI. In the second part, the results obtained from the first section were validated by implementing these results in real residential projects, located in the very climate zones. This allows the current work to study comparatively the effect of so-called optimum fenestration values on building performance of the real cases. The comparative results suggest optimum fenestration values obtained from a test box model causes no significant improvements in building performance metrics of the real residential projects. As a conclusion, the current work discussed the uniqueness of each architectural design and therefore, the necessity of conducting such performance analysis for each unique case. Keywords: performance-based architecture, computational design, multi-objective optimization, daylighting-energy optimization, fenestration, residential
Bina şeklinin ofis binalarının termal performansı üzerindeki etkisi: Karachi, Pakistan vakası
(2018) Khan, Shahrukh Hussaın; Dursun, Onur
Citation - WoS: 38
Citation - Scopus: 51
Conceptual Estimation of Construction Costs Using the Multistep Ahead Approach
(ASCE-AMER SOC CIVIL ENGINEERS, 2016) Onur Dursun; Christian Stoy; Stoy, Christian; Dursun, Onur
Providing accurate forecasts of construction costs at the conceptual phases of building projects is vital since they form an objective benchmark for the subsequent evaluation of project performance. Previous works adopted a conventional approach in which a restricted set of macro project determinants which are available in the preplanning phase was employed towards direct estimation of construction costs. Aiming to reduce the prediction error in conceptual estimates the current study adopts a novel approach from the domain of forecasting. This multistep ahead (MSA) approach relies on the idea of using several cascaded estimations to predict future values. Accordingly building element quantities were estimated as the first step. In the second step estimated quantities were combined with the existing set of inputs to achieve a higher accuracy in construction cost prediction. In order to test the hypotheses of interest 657 building projects from Germany were analyzed using linear regression and artificial neural network methods. Conclusive evidence suggests that the MSA approach significantly outperforms the prediction accuracy of the conventional practice. To the best of authors' investigation the current study is the first to offer such a cascaded estimation approach. Therefore further empirical evidence is necessary prior to generalizing applicability of the MSA approach in construction cost estimation.
Citation - WoS: 24
Citation - Scopus: 30
Energy dissipation and performance assessment of double damped outriggers in tall buildings under strong earthquakes
(WILEY, 2019) Mauricio Morales-Beltran; Gursoy Turan; Onur Dursun; Rob Nijsse; Morales-Beltran, Mauricio; Dursun, Onur; Nijsse, Rob; Turan, Gursoy
The use of a single set of outriggers equipped with oil viscous dampers increases the damping ratio of tall buildings in about 6-10% depending on the loading conditions. However could this ratio be further increased by the addition of another set of outriggers? Should this additional set include dampers too? To answer these questions several double damped outrigger configurations for tall buildings are investigated and compared with an optimally designed single damped outrigger located at elevation 0.7 of the total building's height (h). Using free vibration double outrigger configurations increasing damping up to a ratio equal to the single-based optimal are identified. Next selected configurations are subjected to several levels of eight ground motions to compare their capability for avoiding damage under critical excitations. Last a simplified economic analysis highlights the advantages of each optimal configuration in terms of cost savings. The results show that within the boundaries of this study combining a damped outrigger at 0.5h with a conventional outrigger at 0.7h is more effective in reducing hysteretic energy ratios and economically viable if compared with a single damped outrigger solution. Moreover double damped outrigger configurations for tall buildings exhibit broader display of optimal combinations which offer flexibility of design to the high-rise architecture.
A Novel Computational Approach in Quantity Take-off to Support Early Design Estimations
(2018) Şendikici, Alaattin Çağlar; Dursun, Onur
Son yıllarda mimarlar, meslek pratiklerindeki uygulamalarının verimliliğini ve hızını önemli ölçüde artıran bilişimsel tasarım araçlarını (CTD) benimsemişlerdir. CDT sadece farklı tasarım alternatiflerinin keşfi ve analizlerinde değil, aynı zamanda yapı metraj hesabı gibi maliyet tahminlerinin doğruluğunu da önemli ölçüde etkileyecek önemli aktivitelerin hızlı ve doğru bir şekilde hesaplanmasında da büyük bir potansiyel sunmaktadır. Fakat, bu tür faydaları kullanmak mimarların zamanın kısıtlı olduğu erken tasarım aşamalarında matematiksel tanımlar oluşturmasını gerektirir. Bu nedenle, sektörde çalışan mimarların birçoğu için bu aktivite son derece zordur. Bina modelleme bilgisi (BIM) yazılımı, bu konulara ve daha fazlasına, çözüm önerileri sunmaktadır. Buna karşın, BIM sisteminin metraj alma kapasitesi, doğruluğu ve sonuçları sınırlıdır. Bunun sebebi, BIM çıktılarının mimarın modelleme becerilerine bağlı olmasıdır. Dahası, BIM sisteminin sunduğu çözümlerinden yararlanmak için, mimarlık ofislerin ciddi bir maliyet ödemesi gereklidir. Özellikle küçük ölçekli mimarlık ofisleri için maliyet önemli bir sorundur. Mevcut sorunlar ele alındığında BIM yöntemine alternatif olarak standart matematiksel tanımların CDT kullanarak geliştirilmesi önerilebilir. Potansiyel faydalarına rağmen, literatürde çok az sayıda çalışma CDT yöntemi kullanılarak metraj hesabı uygulamalarına odaklanmıştır. Ek olarak, CDT, BIM ve geleneksel yoğun iş gücü gerektiren yaklaşımlardan elde edilen sonuçları karşılaştıran ampirik çalışmaların sayısında fazlaca eksiklik görülmüştür. Mevcut çalışma bu boşluğu doldurmayı amaçlamaktadır. Çalışma kapsamında ilk olarak parametrik bir CDT olan Grasshopper kullanılarak matematiksel tanımlamalar geliştirilmiştir. Ardından, on gerçek bina projesi seçilmiştir. Bu yapıların metraj hesapları çalışma kapsamında ele alınan üç farklı yönteme göre hesaplanmış ve sonuçlar hipotez testi kullanılarak karşılaştırılmıştır. Elde edilen bulgular, önerilen bilgisayımsal yöntem sonuçları ve gerçek değerler arasında anlamlı bir fark olmadığını önermektedir. Dahası, bilgisayımsal yöntem BIM ve geleneksel yöntemlerden elde edilen sonuçlara kıyasla, tahmin doğruluğunda anlamlı olarak daha yüksek sonuçlar vermektedir.
Ön tasarım aşaması kararlarının enerji kullanımı üzerine etkisi: Duyarlıklık analizi ile kantitatif değerlendirme
(2018) İşeri, Orçun Koral; Dursun, Onur
Architectural design is a complex problem which contains multiple design parameters and constraints. Particularly, early architectural design includes all the major decision-making process that defines the framework of yearly energy demand of the unit. Due to time constraints and uncertainty of the energy demand at early design it is important to analyze the process starting from the early design. To reduce the complexity of model, quantify output uncertainty and lastly understand the relation between independent and dependent variables, in the current study, Morris and Sobol' global sensitivity analysis have applied for one zone office building to support a decision-making guidance for designers with regards to specified quasi random sampling methods. As energy modelling composes from physical properties of the building and weather type, procedure has been conducted for cold climate of Erzurum and hot-humid climate of Izmir. Firstly, ineffective parameters factor fixing is implied than factor prioritization is illustrated with Morris analysis. Afterwards, by using variance based Sobol' sensitivity analysis, first and total order effects are investigated for each climate. Thirdly, a performance filtering process has been executed for 100 best high energy performances of samples to illustrate each of them by presenting the valuable range values of parameters with Parallel Coordinate Plot (PCP). Lastly, a comparison has been implemented for how input parameter and its values are changing according to climate type. For further works, it is aiming to apply all the process for specified design of building by adding Monte Carlo filtering applications.
Citation - WoS: 7
Optimisation of energy consumption and daylighting using building performance surrogate model
(UNIV MELBOURNE, 2015) Elif Esra Aydin; Onur Dursun; Ioannis Chatzikonstantinou; Berk Ekici; Ekici, Berk; Chatzikonstantinou, Ioannis; Aydin, Elif Esra; Dursun, Onur; RH Crawford; A Stephan
Today the architects are expected to identify solutions that provide best trade-offs among an excessively large number of possible design alternatives. Within this context computational intelligence techniques prove to be valuable decision support tools. In parallel to this agenda the current study aimed to present a novel approach towards identifying non-dominated design solutions that minimize annual building energy consumption and improve indoor daylight conditions. We applied the method to an L plan shaped office design. In this hypothetical building design parameters of footprint area number of levels fenestration shading U-Values of building elements and HVAC system selection were set as variables, whereas total floor area and floor height were kept as constants in order to facilitate further practical relevance. A total of 105 simulations were performed for various values of the parameters. The resulting dataset was used to obtain two approximation models for each of the objective functions. A Multi-Objective Evolutionary Algorithm was subsequently used to obtain the set of non-dominated solutions for the problem. Our results indicated the applicability of the proposed approach for decision-making practices at the conceptual design phase of relevant cases.
Citation - WoS: 2
Citation - Scopus: 2
Optimizing Natural Ventilation Strategy in Existing Buildings using Differential Evolution Case of Architectural Studio Classrooms
(IEEE, 2016) Damla Elbi; Huma Fulya Ekim; Onur Dursun; Ekim, Huma Fulya; Elbi, Damla; Dursun, Onur
Natural ventilation plays a vital role towards provision of healthy indoor environment condition for occupants in a building. Yet particularly in winter providing sufficient level of fresh air to indoor environment causes a significant increase in heating energy consumption. To this end the current study aims to propose an optimum natural ventilation strategy while minimizing heating energy consumption and ventilation time which are constrained by minimum allowable fresh air intake. To demonstrate we considered an actual case for the problem at hand which is an architectural studio classroom located in Yasar University Turkey. Next the problem was mathematically formulated using basic physical rules. Comparing results between energy simulation of the considered case and formulated problem accuracy of mathematical expressions was verified. Following we made use of differential evolution ( DE) to find the non-dominated set of natural ventilation strategy. The results suggests that DE is able to converge a set of optimum ventilation strategies after adequate number of generations.
Citation - WoS: 2
Citation - Scopus: 2
Optimizing Wall Insulation Material Parameters in Renovation Projects using NSGA-II
(IEEE, 2016) Hizir Gokhan Uyduran; Orcun Koral Iseri; Yarkin Ustunes; Onur Dursun; Iseri, Orcun Koral; Dursun, Onur; Uyduran, Hizir Gokhan; Ustunes, Yarkin
Renovation works introduce numerous complexities that can only be addressed by those who excel in this specific design task. Such issues as energy consumption which requires examination of excessive alternatives is not of primary concern through the design process due further time limitations. However computational intelligence methods prove to be valuable decision support tools. To this end the current study aims to determine optimum wall insulation material parameters while minimizing optimization targets namely energy consumption and investment costs. To accomplish first energy model of an actual case located in the province of Selcuk was developed using OpenStudio cross platform. Following 54 simulations were run to generate the data base for the given parameters of selected insulation alternatives. Subsequently generated data base was employed to train predictive models of energy generation and investment costs. Finally optimization targets were minimized using NSGA-II algorithm. Results rigorously demonstrate that NSGA-II was able to converge a set of non-dominated set of solutions.
Sanal mekânların mimari tasarım eğitimindeki rolü: Mekânsal algı ve uzaktan işbirliği
(2018) Ölmez, Duhan; Dursun, Onur
Since architecture as a domain has different working fields, architectural education and practice have discussions about, as well as the definition of architecture. A consensus has been achieved to put design studios as a core element of architecture education. While traditional presentation methods are used widely, technological approaches emerged such as on-screen virtual environments and immersive virtual reality systems. To compare the effectiveness of traditional and technological architectural representation approaches, previous studies adopted experimental designs. However, the design of experiments in previous works were based on single event activities and required financially not feasible setups. The previous studies on virtual collaboration in architecture are based on raw data exchange, verbal communication and transferred texts without the use of collaborative 3D virtual environments. This study aims to investigate how digital presentation methods influence spatial perception, to analyze the distant feedback efficiency through the digital data, and to define an application of distant collaboration for architecture students. This study uses a semester of an elective course and sets of tasks for architecture students. The data collection, virtual presentation setups, and distant communication handled through low-cost and cross-platform digital applications. Various experiments have been conducted to compare different presentation methods and measure the effectiveness of distant collaboration and feedback process in virtual environments. Results indicated that digital presentation methods have various advantages for understanding the project, volumes, surfaces, organizations, etc. Also, digital review systems increased collaboration between students, by focusing on the architectural work rather than personal communication between themselves. As a significant outcome, participants were comfortable using both on-screen virtual environment and immersive virtual reality.
Tepkisel kinetik gölgeleme araçlarının erken tasarım aşamalarında performans değerlendirmesi için özgün bir yaklaşım
(2017) Teksoy, Mustafa; Sarıyıldız, İkbal Sevil; Dursun, Onur
Computational tools offer a great potential in the conceptual phase of architectural design, towards exploring numerous design alternatives that provide better environmental impact. Particularly in the domain of solar control with help of kinetic shading devices that respond to its environment, the function of computational tools is even more significant, since the determination of the control parameters introduces a dynamic problem. However, critical review of relevant literature suggests that the utilization of computational tools have failed to address some vital aspects. This has led exclusion of many design alternatives and weather conditions due to the high computational expenses. To this end, the current study aims to investigate the problem of adequately exploring the design space and evaluating the performance of responsive-kinetic shading devices (RKSD). For this purpose, we proposed a novel framework by implementing a surrogate-based technique for multi-objective optimization of control parameters of a conceptual RKSD on randomly sampled daylight hours. To test the adequacy of the proposed framework, an experimental research was designed. In this design, such methods as parameter initiation, variable randomization, simulation, database generation, neural networks, optimization, and hypothesis test were used in combination. Results revealed that using proposed framework one can adequately reach to optimum set of solutions in a fraction of a time when compared to traditional simulation-based optimization methods. More, utilizing proposed framework one can formally compare the performances between static shading and RKSD. In the case of our experimental design, RKSD outperforms the static one in daylighting and view metrics. However, considering indoor temperature no significant differences observed. To the best of our knowledge, the current work is the first to propose a framework, which allows an end user to conduct a formal comparison of selected performance metrics between responsive-kinetic and optimized-static shadings. The further works shall focus on the relationships between the weather conditions, design parameters, and the performance objectives. Due complex interactions among employed techniques, a user-friendly graphical user interface establishment shall also be in the agenda.
Citation - Scopus: 8
Time-cost optimization at the conceptual design stage using differential evolution
(Institute of Electrical and Electronics Engineers Inc., 2015) Onur Dursun; Berk Ekici; I. Sevil Sariyildiz; Ekici, Berk; Sariyildiz, Sevil; Dursun, Onur
Concurrent minimization of construction cost and duration is a challenging task for architects through conceptual design. Using differential evolution (DE) this study aims to obtain optimum design solutions that minimize unit cost of construction and construction duration. Single family housing projects in Germany is sampled with the intent of developing objective functions with regression analysis. The results suggests that DE is able to converge a set of optimum design solutions after adequate number of generations. Resemblance between descriptive statistics of the sampled observations and DE results underpins that regression models can be employed to develop objective functions in the presence of reliable and structured data. In addition results by the formal test of hypothesis based on hypervolume indicator offers DE/rand/1/bin outperforms DE/rand/2/bin irrespective of building standard. Last but not least solutions offered by DE allows us to discuss insights regarding design economics. © 2017 Elsevier B.V. All rights reserved.
Citation - WoS: 7
Time-Cost Optimization at the Conceptual Design Stage Using Differential Evolution Case of Single Family Housing Projects in Germany
(IEEE, 2015) Onur Dursun; Berk Ekici; Sevil Sariyildiz; Ekici, Berk; Sariyildiz, Sevil; Dursun, Onur
Concurrent minimization of construction cost and duration is a challenging task for architects through conceptual design. Using differential evolution (DE) this study aims to obtain optimum design solutions that minimize unit cost of construction and construction duration. Single family housing projects in Germany is sampled with the intent of developing objective functions with regression analysis. The results suggests that DE is able to converge a set of optimum design solutions after adequate number of generations. Resemblance between descriptive statistics of the sampled observations and DE results underpins that regression models can be employed to develop objective functions in the presence of reliable and structured data. In addition results by the formal test of hypothesis based on hypervolume indicator offers DE/rand/1/bin outperforms DE/rand/2/bin irrespective of building standard. Last but not least solutions offered by DE allows us to discuss insights regarding design economics.