Davutpasa Campus Research Articles

Towards to Zero Carbon Emission at YTU Davutpasa Campus

Towards to Zero Carbon Emission at YTU Davutpasa Campus

Towards zero carbon emission at YTU Davutpasa Campus

Towards zero carbon emission at YTU Davutpasa Campus

Automatic detection of single street trees from airborne LiDAR data based on point segmentation methods

As a primary element of urban ecosystem, street trees are very essential for environmental quality and aesthetic beauty of urban landscape. Street trees play a crucial role in everyday life of city inhabitants and therefore, comprehensive and accurate inventory information for street trees is required. In this research, an automatic method is proposed to detect single street trees from airborne Light Detection and Ranging (LiDAR) point cloud instead of traditional field work or photo interpretation. Firstly, raw LiDAR point cloud data have been classified to obtain high vegetation class with a hierarchical rule-based classification method. Then, the LiDAR points in high vegetation class were segmented with mean shift and Density Based Spatial Clustering of Applications with Noise (DBSCAN) algorithms to acquire single urban street trees in the Davutpasa Campus of Yildiz Technical University, Istanbul, Turkey. The accuracy assessment of the acquired street trees was also conducted using completeness and correctness analyses. The acquired results from urban study area approved the success of the proposed point-based approach for automatic detection of single street trees using LiDAR point cloud.

Performance analysis of rule-based classification and deep learning method for automatic road extraction

The need for accurate and up-to-date spatial data by decision-makers in public and private administrations is increasing gradually. In recent decades, in the management of disasters and smart cities, fast and accurate extraction of roads, especially in emergencies, is quite important in terms of transportation, logistics planning, and route determination. In this study, automatic road extraction analyses were carried out using the Unmanned Aerial Vehicle (UAV) data set, belonging to the Yildiz Technical University Davutpasa Campus road route. For this purpose, this paper presents a comparison between performance analysis of rule-based classification and U-Net deep learning method for solving automatic road extraction problems. Objects belonging to the road and road network were obtained with the rule-based classification method with overall accuracy of 95%, and with the deep learning method with an overall accuracy of 86%. On the other hand, the performance metrics including accuracy, recall, precision, and F1 score were utilized to evaluate the performance analysis of the two methods. These values were obtained from confusion matrices for 4 target classes consisting of road and road elements namely road, road line, sidewalk, and bicycle road. Finally, integration of classified image objects with ontology was realized. Ontology was developed by defining four target class results obtained as a result of the rule-based classification method, conceptual class definition and properties, rules, and axioms.

The Use of Machine Learning Algorithms in Urban Tree Species Classification

Trees are the key components of urban vegetation in cities. The timely and accurate identification of existing urban tree species with their location is the most important task for improving air, water, and land quality; reducing carbon accumulation; mitigating urban heat island effects; and protecting soil and water balance. Light detection and ranging (LiDAR) is frequently used for extracting high-resolution structural information regarding tree objects. LiDAR systems are a cost-effective alternative to the traditional ways of identifying tree species, such as field surveys and aerial photograph interpretation. The aim of this work was to assess the usage of machine learning algorithms for classifying the deciduous (broadleaf) and coniferous tree species from 3D raw LiDAR data on the Davutpasa Campus of Yildiz Technical University, Istanbul, Turkey. First, ground, building, and low, medium, and high vegetation classes were acquired from raw LiDAR data using a hierarchical-rule-based classification method. Next, individual tree crowns were segmented using a mean shift clustering algorithm from high vegetation points. A total of 25 spatial- and intensity-based features were utilized for support vector machine (SVM), random forest (RF), and multi-layer perceptron (MLP) classifiers to discriminate deciduous and coniferous tree species in the urban area. The machine learning-based classification’s overall accuracies were 80%, 83.75%, and 73.75% for the SVM, RF, and MLP classifiers, respectively, in split 70/30 (training/testing). The SVM and RF algorithms generally gave better classification results than the MLP algorithm for identifying the urban tree species.

Integration of custom street view and low-cost motion sensors

Virtual reality is an artificial computer-generated environment generally referred as virtual reality environment which can be navigated and interacted with by a user. Street View, which was released by Google in 2007, is an ideal tool to discover places and locations. This service doesn’t only provide spatial information, but also a virtual reality environment for the user. Since this service is only available in certain locations, Google enables users to create a street view with custom panoramic images with the help of Google Maps Application Programming Interface (API) for JavaScript. In this study, it is aimed to integrate body motions with a custom created street view service for Yildiz Technical University Davutpasa Campus which has a historical environment and huge places to discover. Microsoft Kinect for Xbox 360 motion sensor along with Flexible Action and Articulated Skeleton Toolkit (FAAST) interface has been employed for this purpose. This integration provides a low-cost alternative for virtual reality experience. The proposed system can be implemented for virtual museums, heritage sites or planetariums consisting of panoramic images.

Inclusive Design and Practices in Education: A Pilot Study in Davutpasa Campus

The public sphere of the city where the social relations of the social individuals live intensely has an important role in urban development. In addition to these changing circumstances, new requirements and problems such as the inclusion of these areas arise. It is an approach to raise awareness among university students as the main campus users who will increase and improve the spatial quality in professional life by increasing the awareness of university students who will continue the development of society, communities and cities and by increasing the quality of university campuses and spreading this philosophy within the society. The problem faced by users on university campuses is defined by surveys that enable all users to access campus equipment and develop solutions that enable them to use it as they wish. The aim of this study is to see the Davutpasa Campus’s inclusivity. In this context, a pilot study was conducted and the results were evaluated. At this stage of the study, the intelligibility of the questions and the adequacy of the answers were evaluated in terms of the nature of the questionnaire study.

Numerical modelling of transient soil temperature distribution for horizontal ground heat exchanger of ground source heat pump

A ground heat exchanger is the most important part of a ground source heat pump system. Soil properties and ground heat exchanger performance strongly depend on soil temperature profile and vary with time and space. Also, soil temperature profile is a function of heat transfer rate extracted or transferred to soil. Studies in the literature either use the unaffected soil temperature obtained from meteorological data or fail to run for long time periods to obtain a steady periodic soil temperature profile and over-predict the ground heat exchanger performance. Therefore, steady periodic temperature profile should be used for sizing ground heat exchanger for efficient operation of ground source heat pumps for longer periods of time. Experimental studies are carried out on a ground-source heat pump established at Yıldız Technical University, Davutpaşa Campus and the newly developed numerical model is validated with experimental results. For the numerical study, the hourly required heat load of a 200 m2 office in Istanbul during the heating season is calculated by using HAP software. The transient soil temperature profile is obtained numerically for longer periods of time with realistic boundary conditions using meteorological data. The fluid inlet temperatures equivalent to the hourly need for heating load of the office during the heating season are simulated for a ten-year period in accordance with the different heat amounts extracted from unit pipe length in soil (21, 10.5 and 7 W/m). The effects of burial depth, distance between pipes and surface effects on soil temperature are also investigated. Horizontal and vertical temperature distribution in soil at the beginning (November 10th), middle (January 21st) and end (April 3rd) of the first, fifth and tenth years are represented.

Evaluation of Wind Energy Potential in a University Campus

Today, zero energy campus concept is a popular topic. Zero energy attempts are important for reducing global warming effect and greenhouse gas emissions. In the current study, wind characteristics and wind energy potential of Yildiz Technical University Davupasa Campus were investigated. Data from wind measurement station (10 m height) in campus area was examined. Due to the gaps in the measured data, one year long data was lumped by using all the measured data (25 months). The lumped data was used in all energy analyses. Mean wind speed was calculated as 3.45 m/s at 10 m and north northeast (30°) was defined as prevailing wind direction. Annual wind energy production and capacity factor for Fuhrlander FL 30 (30 kW-27 m hub height) wind turbine were estimated as 28.87 MWh and 10.9%, respectively. According to these results, an economically feasible wind energy project seems not possible. However, a possible wind energy project in Davutpasa campus will help to raise awareness of people. Therefore, it will help and promote to catch the aimed future wind energy capacity of Turkey.

Real-time performance analysis of an optimally sized hybrid renewable energy conversion unit

• Experimental analysis of a stand-alone hybrid system. • Construction of a test bench and all necessary power conditioning units. • Verification of pre-obtained optimum sizing results. • Evaluation of hybrid system performance under different case studies. Lately, interest in renewable sources, especially for wind and solar energy, has gained a significant momentum with an increasing share of installed power production facilities of these sources together with the incentives of many developed/developing country governments. However, the intermittent structure of the wind and solar energy systems directly related with the dependence on meteorological conditions lowers the reliability of such sources especially for sole use in a stand-alone small scale system. Thus, utilizing these sources with energy storage units in a proper hybrid combination is the most accepted solution today to overcome the mentioned drawbacks of solar and wind systems. In order to make the mentioned hybrid system investment as economic as possible together with considering technical limitations, optimum sizing algorithms have been widely utilized. In this paper, a real-time performance analysis of an optimally sized hybrid energy system is conducted to examine the effectiveness of the optimum sizing approach proposed in a recent study of the authors. The experimental tests have been realized in Davutpasa Campus of Yildiz Technical University, Istanbul considering different case studies and worst case scenarios.

The Processing of Image Data Collected by Light UAV Systems for GIS Data Capture and Updating

Abstract. The collection and updating of 3D data is the one of the important steps for GIS applications which require fast and efficient data collection methods. The photogrammetry has been used for many years as a data collection method for GIS application in larger areas. The Unmanned Aerial Vehicles (UAV) Systems gained increasing attraction in geosciences for cost effective data capture and updating at high spatial and temporal resolution during the last years. These autonomously flying UAV systems are usually equipped with different sensors such as GPS receiver, microcomputers, gyroscopes and miniaturized sensor systems for navigation, positioning, and mapping purposes. The UAV systems can be used for data collection for digital elevation model DEM and orthoimages generation in GIS application at small areas. In this study, data collection and processing by light UAV system will be evaluated for GIS data capture and updating for small areas where not feasible for traditional photogrammetry. The main aim of this study is to design the low cost light UAV system for GIS data capture and update. The investigation was based on the aerial images which recorded during the flights performed with UAV system over the test site in Davutpasa Campus of Yildiz Technical University, Istanbul. The quality of generated DEM and ortho-images from UAV flights was discussed for GIS data capture and updating for small areas.

ChemInform Abstract: Synthesis of New Aryl‐Substituted Tandospirone and Epiboxidine Analogues and Isoxazoline Derivatives.

AbstractNew tandospirone [cf.(IIIa)—(IIId)] and epiboxidine analogues [cf.

Erratum to: ‘n-tuplet fixed point theorems for contractive type mappings in partially ordered metric spaces’

*Correspondence: merturk3263@gmail.com 1Department of Mathematics, Yildiz Technical University, Davutpasa Campus, Esenler, Istanbul, Turkey Full list of author information is available at the end of the article Correction () Page , line : The statement ‘(ii) limr→t+ φ(r) ’ should be corrected as ‘(ii) limr→t+ φ(r) ’. () Page , line : The statement ‘. . . Condition  is satisfied.’ should be rewritten ‘. . . Condition  is satisfied and g is continuous.’ () Page , line : The statement ‘. . . and using (.)’ should be corrected as ‘. . . and using (.)’. () Page , line : The statement ‘≤ δj(k)+ + δl(k)+ + tk + n · φ( tk n )’ should be corrected as ‘≤ δj(k)+ + δl(k)+ + n · φ( tk n )’. () Page , line : The statement ‘From (.) and by . . .’ should be corrected as ‘From (.) and by . . . ’. () Page , line : ‘. . . now the assumption (b) holds.’ should be corrected as ‘. . . now the assumption (ii) holds.’ () Page , line  (line  in Corollary ) and Page , line  (line  in Corollary ): The statement ‘and there exist φ ∈ such that F ’ should be deleted. () Page , line  (line  in Corollary ) and Page , line  (line  in Corollary ): The statement ‘φ(F(x,x, . . . ,xn),F(y, y, . . . , yn))’ should be corrected as ‘d(F(x,x, . . . ,xn),F(y, y, . . . , yn))’. () Page , line  (line  in Corollary ) and Page , line  (line  in Corollary ): The statement ‘. . .F has the mixed g-monotone’ should be corrected as ‘. . .F has the mixed monotone’. That is, ‘g-’ should be deleted. () Page , line : ‘≤ φ( d(g(x),g(y))+d(g(x),g(y))+···+d(g(xn),g(yn)) n )’ should be corrected as ‘≤ φ( d(x,y)+d(x,y)+···+d(xn ,yn) n )’. () Page , line : ‘≤ n [d(g(x), g(y)) + d(g(x), g(y)) + · · · + d(g(xn), g(yn))]’ should be corrected as ‘≤ n [d(x, y) + d(x, y) + · · · + d(xn, yn)]’.

Synthesis of New Aryl-substituted Tandospirone and Epiboxidine Analogues and Isoxazoline Derivatives

Synthesis of New Aryl-substituted Tandospirone and Epiboxidine Analogues and Isoxazoline Derivatives Irem Kulu a , Gokce Goksu a , Bilgesu Onur Sucu a , Asli Kopruceli a , Nuket Ocal a & Dieter E. Kaufmann b a Yildiz Technical University, Faculty of Science and Arts, Department of Chemistry, Davutpasa Campus, 34220, Esenler, Istanbul, Turkey b Institute of Organic Chemistry, Clausthal University of Technology, Leibnizstr. 6, D-38678, Clausthal-Zellerfeld, Germany

Identification and Apportionment of Sources of Ozone‐forming Potential for Proper Reduction Strategies

AbstractIn this study, results of source identification and apportionment for ambient volatile organic compounds (VOCs) from a previous work were used to estimate ozone‐forming potentials (OFPs) of effective sources for developing proper strategies for reduction of tropospheric ozone pollution. The source identification and apportionment of ambient VOC pollution within Yildiz Technical University's Davutpasa Campus (Istanbul, Turkey) was done by positive matrix factorization (PMF). The results suggested five effective source groups with the emissions related with paint use and solvent use having the highest contributions (36.8 and 28.2%). The results from PMF were used along with maximum incremental reactivities to estimate potentials of individual sources for ozone formation. It was found that biogenic emissions (3.78) and traffic related emissions (gasoline and diesel vehicle exhaust) (3.83 and 3.15, respectively) have the highest potential for ozone formation in terms of grams O3/g VOC emitted. The results were used to suggest proper source‐based reduction strategies for OFP.

Evaluation (POE) of Yildiz Technical University (YTU) School of Foreign Languages (SFL)

This paper deals with the post-occupancy performance evaluation of the SFL (School of Foreign Languages) that was designed by the authors and is located within the YTU (Yildiz Technical University) Davutpasa campus in Istanbul. After the completion and occupation of the building, project review came into question and a POE was performed. Post-occupancy performance evaluation tries to answer the questions of space provision for social interaction: How is this building working? Is it intended? How can it be improved? and How can future buildings be improved? Answers to these vital questions are searched under four main sections. In the first section, the study discusses the physical location and functional properties of the building, in the second, the design decisions of the building are discussed in the context of and design principles, in the third, the method of performance evaluation is explained, and in the final section, the results are analyzed and discussed. These results will lead to a path to improve the quality of the building.

Effect of diurnal changes in VOC source strengths on performances of receptor models

The effect of diurnal changes in strengths of volatile organic compound (VOC) sources on the performances of positive matrix factorization (PMF) and principal component analysis (PCA) was investigated using ambient measurement results that were taken during daytime and nighttime hours between March 24 and May 14, 2011, within Davutpasa Campus of Yildiz Technical University (Istanbul, Turkey). Forty-five VOC species, ranging from C(5) to C(11) in volatility, were measured in the samples, 40 of which are included in the analyses. Ambient samples were grouped as daytime, nighttime, and all day datasets, and both PMF and PCA were applied to each dataset. A total of six source groups were extracted from each dataset: solvent use, general industrial paint use, gasoline and diesel vehicle exhausts, and biogenic as well as evaporative emissions. Estimated source contributions showed great diurnal variations. The results suggested that extraction of possible sources by PCA depends greatly on the number of samples and the strength of the sources, while PMF produced stable results regardless of number of samples and source strengths. Although PMF was unable to resolve gasoline vehicle and evaporative emissions, it was found to be successful in explaining diurnal fluctuations in source strengths, while the performance of PCA depends on the strength of emission source.

University Library Buildings in Turkey: A Survey and a Case Study of Yildiz Technical University Main Library Building

Higher education in Turkey has an ancient heritage, beginning in the ‘medrese’ or ‘madrasah’, schools for young men attached to a mosque, which date back to the tenth century and earlier throughout the Islamic world. The first university in Turkey, now known as Istanbul Universitesi, grew out of the Istanbul Medrese, founded as early as 1453, which gradually established itself as a pre-eminent science and technology school throughout the nineteenth century, taking the name Istanbul Darulfunun (House of Multiple Sciences) in 1912, and Istanbul Universitesi in 1933. Its former Schools, based on the schools of the former Medrese, have become Faculties in the modern university. There are now more than ninety-seven universities and academies in Turkey, of which approximately two thirds are state owned, the others are funded by foundations, or are military or police academies. Yildiz Technical University, founded in 1911, is one of the largest and most prominent state universities in Istanbul, and one of two technical universities, the other being Istanbul Technical University (founded 1773). YTU offers programs within eight faculties (covering literature, languages, fine arts and design, engineering and architecture) across three campuses, and advanced research degrees in dedicated research institutes. Although not the oldest university in Istanbul, many of its buildings, especially on the historic Davutpasa campus, date from the first half of the twentieth century and are ill-equipped to provide for the needs of a modern university, let alone a modern university library.