Kentler, yaşayan canlı organizmalara benzetilebilir. İnsanların ihtiyaçları doğrultusunda gelişir... more Kentler, yaşayan canlı organizmalara benzetilebilir. İnsanların ihtiyaçları doğrultusunda gelişirler, ihtiyaçların değişmesi ile fonksiyon değiştirler. Zamanla ya da doğal afetler gibi zorlayıcı etkiler ile yıpranırlar ve yenilenmeye ihtiyaç duyarlar. İnsanların zaman içinde yaşadıkları pek çok sosyal olgununda kentlerde değişime neden olduğu bilinmektedir. Dünya nüfusu hızla artmaktadır, artan nüfus ağırlıklı olarak şehirlerin sunduğu cazip imkânlardan dolayı kentlerde yaşama arzusundadır. Tüm bunlar yeni yerleşim alanlarının imara açılmasını gerektirdiği gibi, zamanla yetersiz ya da sağlıksız hale gelen kent içi alanların da yeniden kente kazandırılmasını gündeme getirmektedir. Zira arazi sınırlıdır ve her arazi parçası yerleşime uygun değildir. Kentsel dönüşümü en genel ifadeyle çarpık yapılaşmış, yetersiz altyapıya sahip, imara aykırı ve afet riski altındaki yerlerin yeni imar planı verilerine uygun olarak düzenlenmesi şeklinde tanımlamak mümkündür. Kentsel dönüşüme girecek parsellerin değerlerinin doğru olarak belirlenmesi süreç içerisinde ekonomi ve zaman kaybı yaşanmaması için önemlidir. Bu çalışmada Yalova ili Bağlarbaşı Mahallesi kentsel dönüşüm uygulama sahasındaki bir alan uygulama alanı olarak seçilmiştir. Belediye ve Kadastro Müdürlüğü gibi kamu kurumlarından alana ait sayısal veriler ile sayısal olmayan veriler temin edilmiştir. Alanın yerinde incelemesi yapılarak konumsal ve konumsal olmayan değerlemeyi etkileyecek öznitelik verilerine ulaşılmıştır. Değer haritalarının üretiminde Coğrafi Bilgi Sistemi (CBS) teknolojileri kullanılmıştır. Çalışma alanı olarak seçilen Yalova ili Bağlarbaşı Mahallesi kentsel dönüşüm uygulama sahasında birden fazla öznitelik bilgileri değerlendirilerek ayrı ayrı değer haritaları oluşturulmuştur. Toplam değerler üzerinden sonuç değer haritası üretmek amacıyla çalışma alanında yer alan kadastro parsellerinin kıyıya uzaklıkları, okula uzaklıkları ile alan ve metrekare üzerinden hesaplanmış olan değerleri normalizasyon metodu uygulanarak veri seti değerleri 0 ile 1 arasında normalize edilmiştir.
Thanks to advances in current technology and computer software, mathematical computations and eng... more Thanks to advances in current technology and computer software, mathematical computations and engineering applications that used to require hours or even days can now be performed quickly. Cartography, unquestionably one of the world's oldest branches of scientific study, is among the fields that have been most influenced by technological improvements. These improvements have enhanced interest in historical maps while also paving the way for modern mapping. All of this process has created new topics of study for cartographers. Also, it is possible to examine old maps using the Map Analyst software which can enable the investigation of time dependent changes. Helmert, Affine and Huber loss function as robust estimation method were analysed. Thanks to the distortion grids, it can be observed in which region the movement is denser. In this study, by using 29 absolute tie points, the old Istanbul maps (the German Blue maps produced in 1913-1914 and the Moltke maps produced in 1836-1...
Reproduction of the tiles often utilized as finishing material in Ottoman architecture is on the ... more Reproduction of the tiles often utilized as finishing material in Ottoman architecture is on the agenda during the restoration of the buildings. The documentation should be prepared before passing it on to the reproduction of the tiles. In this study, photogrammetric modeling has been used for the documentation of an Ottoman replica tile. The primary goal of the photogrammetric measurement system was to solve the problem of the issues concerning the time and the accuracy of modeling of small objects. Photogrammetric modeling is the best model that enables the minimum margin of error and documentation of the original model. There are conventional drawing methods for tile conservation and documentation. Photogrammetric modeling technique is faster and more precise than the conventional documentation. This modeling technique has the main advantage of measuring and modeling CAD documentation without touching the tile surface.
Modern Fuzzy Control Systems and Its Applications, 2017
The digital cameras have been effected from systematical errors which decreased metric quality of... more The digital cameras have been effected from systematical errors which decreased metric quality of image. The digital cameras have been effected from systematical errors that decreases metric quality of image. The aim of this chapter is to explore usability of fuzzy logic on calibration of digital cameras. Therefore, a 145-pointed planar test field has been prepared in the laboratories of Department of Geodesy and Photogrammetric Engineering at the Gebze Technical University. The test field has been imaged from five points of view with the digital camera Nikon Coolpix-E8700 within maximum (71.2 mm) and minimum (8.9 mm) focal length. The input-output data have been determined from 10 calibration images obtained for fuzzy logic process. These data have also been used and formed for the space resection process. Adaptive neuro-fuzzy inference system (ANFIS) functions have been used for fuzzy process at MATLAB 7.0, and the results of these two distinct methods have been compared. Finally, the most convenient (least squares average error) or the most useful ANFIS "Trimf, trapmf, gbellmf, gaussmf, gauss2mf, pimf, dsigmf and psigmf" functions are determined and compared for space resection method for the conventional bundle adjustment process.
Currently, as a result of the massive continuous advancements in laser measurement technology, po... more Currently, as a result of the massive continuous advancements in laser measurement technology, possibilities of map production are broadened, the loss of time and the waste of material sources are highly prevented, and the accuracy and precision of the obtained results are significantly improved. In the view of engineering concept. However, big data which are from laser point clouds have been especially used in the significant procedures of surveying studies. Programming methods are dependent in each studies. In the necessity of the applications, the coding procedure has more efficient, the data of work has increased, and time has been consumed. The coding methods have necessarily been optimized for working together especially in the big data studies. In this section, an automated survey (building facade surveying) is produced from scanning data by means of coding in MatLAB.
Positioning of a GPS-equipped (Global Positioning System) moving target was determined by stereo-... more Positioning of a GPS-equipped (Global Positioning System) moving target was determined by stereo-videogrammetry from two images of cameras where they were placed on another GPS-equipped moving platform. The computed position outputs of target were compared with the relative positions obtained from two GPS receivers. The target, a small square-like pattern, was tracked from a certain distance depending on the base distance between the cameras. The video files were created from acquired images data. These video files were used in real-time computation to get the target image position for every film frame. First, the location of target was computed within video film frames. Since the target cannot be searched on the whole picture, maximum pixel length, which the target can travel on the consecutive film frames was considered as offset. Therefore, the search was made over a small area rather than whole picture. That was improved the performance of positioning. Finally, videogrammetrically computed coordinates for all epochs were compared with GPS-based relative distances to justify performance of relative target positioning results.
Terrestrial Laser Scanners (TLS) are used frequently in three dimensional documentation studies a... more Terrestrial Laser Scanners (TLS) are used frequently in three dimensional documentation studies and present an alternative method for three dimensional modeling without any deformation of scale. In this study, point cloud data segmentation is used for photogrammetrical image data production from laser scanner data. The segmentation studies suggest several methods for automation of curve surface determination for digital terrain modeling. In this study, fuzzy logic approach has been used for the automatic segmentation of the regular curve surfaces which differ in their depths to the instrument. This type of shapes has been usually observed in the dome surfaces for close range architectural documentation. The model of C-means integrated fuzzy logic approach has been developed with MatLAB 7.0 software. Gauss2mf membership functions algorithm has been tested with original data set. These results were used in photogrammetric 3D modeling process. As the result of the study, testing the results of point cloud data set has been discussed and interpreted with all of its advantages and disadvantages in Section 5.
Terrestrial laser scanning is a popular methodology that is used frequently in the process of doc... more Terrestrial laser scanning is a popular methodology that is used frequently in the process of documenting historical buildings and cultural heritage. The historical peninsula region sprawls over an area of approximately 1,500 ha and is one of the main aggregate areas of the historical buildings in Istanbul. In this study, terrestrial laser scanning and close range photogrammetry techniques are integrated into each other to create a 3D city model of this part of Istanbul, including some of the buildings that represent the most brilliant areas of Byzantine and Ottoman Empires. Several terrestrial laser scanners with their different specifications were used to solve various geometric scanning problems for distinct areas of the subject city. Photogrammetric method was used for the documentation of the facades of these historical buildings for architectural purposes. This study B. Ergun (B) •
Unmanned Aerial Vehicles (UAVs) are often preferred for modeling cultural heritage buildings due ... more Unmanned Aerial Vehicles (UAVs) are often preferred for modeling cultural heritage buildings due to their costs and time savings. The need for data collection, analysis, processing, and visual presentation in the context of cultural heritage buildings has become prominent, underscoring the significance of the concept of Level of Detail (LoD). The utilization of CityGML LoD standards enhances the performance of visual presentations, decreases the geometric complexity of objects, and enables users to view the model at the desired level of detail within a computerized environment. Within the scope of this study, it is aimed to determine the accuracy analysis of the 3D model for a cultural building, which is named Hekimbaşı Hunting Lodge, at different LoDs. Drawings were created at LoD 0-1-2-3 levels with 418 photographs taken by the UAV photogrammetry method. Additionally, conservative and UAV measures of facade detail at the same LoD were compared in terms of accuracy. As a result, RM...
Smartphones from an Applied Research Perspective, 2017
Nowadays, mobile phones are more than a device that can only satisfy the communication need betwe... more Nowadays, mobile phones are more than a device that can only satisfy the communication need between people. Since fisheye lenses integrated with mobile phones are lightweight and easy to use, they are advantageous. In addition to this advantage, it is experimented whether fisheye lens and mobile phone combination can be used in a photogrammetric way, and if so, what will be the result. Fisheye lens equipment used with mobile phones was tested in this study. For this, standard calibration of 'Olloclip 3 in one' fisheye lens used with iPhone 4S mobile phone and 'Nikon FC-E9' fisheye lens used with Nikon Coolpix8700 are compared based on equidistant model. This experimental study shows that Olloclip 3 in one fisheye lens developed for mobile phones has at least the similar characteristics with classic fisheye lenses. The dimensions of fisheye lenses used with smart phones are getting smaller and the prices are reducing. Moreover, as verified in this study, the accuracy of fisheye lenses used in smartphones is better than conventional fisheye lenses. The use of smartphones with fisheye lenses will give the possibility of practical applications to ordinary users in the near future.
Nowadays, mobile phones are more than a device that can only satisfy the communication need betwe... more Nowadays, mobile phones are more than a device that can only satisfy the communication need between people. In addition to providing ease to human lives with various applications, lens kits that can be integrated to mobile phones have recently been introduced. Fisheye lenses that are compliant with mobile phones are one of these new types of equipment. Since fisheye lenses integrated with mobile phones are lightweight and easy to use, they are advantageous. In addition to this advantage, whether fisheye lens and mobile phone combination can be used in a photogrammetric way is experimented, and if so, what will be the result. The main purpose of this study is to test fisheye lens equipment used with mobile phones. In this study, standard calibration of “Olloclip 3 in one” fisheye lens used with iPhone 4S mobile phone and “Nikon FC-E9” fisheye lens used with Nikon Coolpix8700 are compared based on equidistant model. The results of these calibrations are analyzed, using photogrammetric...
Kentler, yaşayan canlı organizmalara benzetilebilir. İnsanların ihtiyaçları doğrultusunda gelişir... more Kentler, yaşayan canlı organizmalara benzetilebilir. İnsanların ihtiyaçları doğrultusunda gelişirler, ihtiyaçların değişmesi ile fonksiyon değiştirler. Zamanla ya da doğal afetler gibi zorlayıcı etkiler ile yıpranırlar ve yenilenmeye ihtiyaç duyarlar. İnsanların zaman içinde yaşadıkları pek çok sosyal olgununda kentlerde değişime neden olduğu bilinmektedir. Dünya nüfusu hızla artmaktadır, artan nüfus ağırlıklı olarak şehirlerin sunduğu cazip imkânlardan dolayı kentlerde yaşama arzusundadır. Tüm bunlar yeni yerleşim alanlarının imara açılmasını gerektirdiği gibi, zamanla yetersiz ya da sağlıksız hale gelen kent içi alanların da yeniden kente kazandırılmasını gündeme getirmektedir. Zira arazi sınırlıdır ve her arazi parçası yerleşime uygun değildir. Kentsel dönüşümü en genel ifadeyle çarpık yapılaşmış, yetersiz altyapıya sahip, imara aykırı ve afet riski altındaki yerlerin yeni imar planı verilerine uygun olarak düzenlenmesi şeklinde tanımlamak mümkündür. Kentsel dönüşüme girecek parsellerin değerlerinin doğru olarak belirlenmesi süreç içerisinde ekonomi ve zaman kaybı yaşanmaması için önemlidir. Bu çalışmada Yalova ili Bağlarbaşı Mahallesi kentsel dönüşüm uygulama sahasındaki bir alan uygulama alanı olarak seçilmiştir. Belediye ve Kadastro Müdürlüğü gibi kamu kurumlarından alana ait sayısal veriler ile sayısal olmayan veriler temin edilmiştir. Alanın yerinde incelemesi yapılarak konumsal ve konumsal olmayan değerlemeyi etkileyecek öznitelik verilerine ulaşılmıştır. Değer haritalarının üretiminde Coğrafi Bilgi Sistemi (CBS) teknolojileri kullanılmıştır. Çalışma alanı olarak seçilen Yalova ili Bağlarbaşı Mahallesi kentsel dönüşüm uygulama sahasında birden fazla öznitelik bilgileri değerlendirilerek ayrı ayrı değer haritaları oluşturulmuştur. Toplam değerler üzerinden sonuç değer haritası üretmek amacıyla çalışma alanında yer alan kadastro parsellerinin kıyıya uzaklıkları, okula uzaklıkları ile alan ve metrekare üzerinden hesaplanmış olan değerleri normalizasyon metodu uygulanarak veri seti değerleri 0 ile 1 arasında normalize edilmiştir.
Thanks to advances in current technology and computer software, mathematical computations and eng... more Thanks to advances in current technology and computer software, mathematical computations and engineering applications that used to require hours or even days can now be performed quickly. Cartography, unquestionably one of the world's oldest branches of scientific study, is among the fields that have been most influenced by technological improvements. These improvements have enhanced interest in historical maps while also paving the way for modern mapping. All of this process has created new topics of study for cartographers. Also, it is possible to examine old maps using the Map Analyst software which can enable the investigation of time dependent changes. Helmert, Affine and Huber loss function as robust estimation method were analysed. Thanks to the distortion grids, it can be observed in which region the movement is denser. In this study, by using 29 absolute tie points, the old Istanbul maps (the German Blue maps produced in 1913-1914 and the Moltke maps produced in 1836-1...
Reproduction of the tiles often utilized as finishing material in Ottoman architecture is on the ... more Reproduction of the tiles often utilized as finishing material in Ottoman architecture is on the agenda during the restoration of the buildings. The documentation should be prepared before passing it on to the reproduction of the tiles. In this study, photogrammetric modeling has been used for the documentation of an Ottoman replica tile. The primary goal of the photogrammetric measurement system was to solve the problem of the issues concerning the time and the accuracy of modeling of small objects. Photogrammetric modeling is the best model that enables the minimum margin of error and documentation of the original model. There are conventional drawing methods for tile conservation and documentation. Photogrammetric modeling technique is faster and more precise than the conventional documentation. This modeling technique has the main advantage of measuring and modeling CAD documentation without touching the tile surface.
Modern Fuzzy Control Systems and Its Applications, 2017
The digital cameras have been effected from systematical errors which decreased metric quality of... more The digital cameras have been effected from systematical errors which decreased metric quality of image. The digital cameras have been effected from systematical errors that decreases metric quality of image. The aim of this chapter is to explore usability of fuzzy logic on calibration of digital cameras. Therefore, a 145-pointed planar test field has been prepared in the laboratories of Department of Geodesy and Photogrammetric Engineering at the Gebze Technical University. The test field has been imaged from five points of view with the digital camera Nikon Coolpix-E8700 within maximum (71.2 mm) and minimum (8.9 mm) focal length. The input-output data have been determined from 10 calibration images obtained for fuzzy logic process. These data have also been used and formed for the space resection process. Adaptive neuro-fuzzy inference system (ANFIS) functions have been used for fuzzy process at MATLAB 7.0, and the results of these two distinct methods have been compared. Finally, the most convenient (least squares average error) or the most useful ANFIS "Trimf, trapmf, gbellmf, gaussmf, gauss2mf, pimf, dsigmf and psigmf" functions are determined and compared for space resection method for the conventional bundle adjustment process.
Currently, as a result of the massive continuous advancements in laser measurement technology, po... more Currently, as a result of the massive continuous advancements in laser measurement technology, possibilities of map production are broadened, the loss of time and the waste of material sources are highly prevented, and the accuracy and precision of the obtained results are significantly improved. In the view of engineering concept. However, big data which are from laser point clouds have been especially used in the significant procedures of surveying studies. Programming methods are dependent in each studies. In the necessity of the applications, the coding procedure has more efficient, the data of work has increased, and time has been consumed. The coding methods have necessarily been optimized for working together especially in the big data studies. In this section, an automated survey (building facade surveying) is produced from scanning data by means of coding in MatLAB.
Positioning of a GPS-equipped (Global Positioning System) moving target was determined by stereo-... more Positioning of a GPS-equipped (Global Positioning System) moving target was determined by stereo-videogrammetry from two images of cameras where they were placed on another GPS-equipped moving platform. The computed position outputs of target were compared with the relative positions obtained from two GPS receivers. The target, a small square-like pattern, was tracked from a certain distance depending on the base distance between the cameras. The video files were created from acquired images data. These video files were used in real-time computation to get the target image position for every film frame. First, the location of target was computed within video film frames. Since the target cannot be searched on the whole picture, maximum pixel length, which the target can travel on the consecutive film frames was considered as offset. Therefore, the search was made over a small area rather than whole picture. That was improved the performance of positioning. Finally, videogrammetrically computed coordinates for all epochs were compared with GPS-based relative distances to justify performance of relative target positioning results.
Terrestrial Laser Scanners (TLS) are used frequently in three dimensional documentation studies a... more Terrestrial Laser Scanners (TLS) are used frequently in three dimensional documentation studies and present an alternative method for three dimensional modeling without any deformation of scale. In this study, point cloud data segmentation is used for photogrammetrical image data production from laser scanner data. The segmentation studies suggest several methods for automation of curve surface determination for digital terrain modeling. In this study, fuzzy logic approach has been used for the automatic segmentation of the regular curve surfaces which differ in their depths to the instrument. This type of shapes has been usually observed in the dome surfaces for close range architectural documentation. The model of C-means integrated fuzzy logic approach has been developed with MatLAB 7.0 software. Gauss2mf membership functions algorithm has been tested with original data set. These results were used in photogrammetric 3D modeling process. As the result of the study, testing the results of point cloud data set has been discussed and interpreted with all of its advantages and disadvantages in Section 5.
Terrestrial laser scanning is a popular methodology that is used frequently in the process of doc... more Terrestrial laser scanning is a popular methodology that is used frequently in the process of documenting historical buildings and cultural heritage. The historical peninsula region sprawls over an area of approximately 1,500 ha and is one of the main aggregate areas of the historical buildings in Istanbul. In this study, terrestrial laser scanning and close range photogrammetry techniques are integrated into each other to create a 3D city model of this part of Istanbul, including some of the buildings that represent the most brilliant areas of Byzantine and Ottoman Empires. Several terrestrial laser scanners with their different specifications were used to solve various geometric scanning problems for distinct areas of the subject city. Photogrammetric method was used for the documentation of the facades of these historical buildings for architectural purposes. This study B. Ergun (B) •
Unmanned Aerial Vehicles (UAVs) are often preferred for modeling cultural heritage buildings due ... more Unmanned Aerial Vehicles (UAVs) are often preferred for modeling cultural heritage buildings due to their costs and time savings. The need for data collection, analysis, processing, and visual presentation in the context of cultural heritage buildings has become prominent, underscoring the significance of the concept of Level of Detail (LoD). The utilization of CityGML LoD standards enhances the performance of visual presentations, decreases the geometric complexity of objects, and enables users to view the model at the desired level of detail within a computerized environment. Within the scope of this study, it is aimed to determine the accuracy analysis of the 3D model for a cultural building, which is named Hekimbaşı Hunting Lodge, at different LoDs. Drawings were created at LoD 0-1-2-3 levels with 418 photographs taken by the UAV photogrammetry method. Additionally, conservative and UAV measures of facade detail at the same LoD were compared in terms of accuracy. As a result, RM...
Smartphones from an Applied Research Perspective, 2017
Nowadays, mobile phones are more than a device that can only satisfy the communication need betwe... more Nowadays, mobile phones are more than a device that can only satisfy the communication need between people. Since fisheye lenses integrated with mobile phones are lightweight and easy to use, they are advantageous. In addition to this advantage, it is experimented whether fisheye lens and mobile phone combination can be used in a photogrammetric way, and if so, what will be the result. Fisheye lens equipment used with mobile phones was tested in this study. For this, standard calibration of 'Olloclip 3 in one' fisheye lens used with iPhone 4S mobile phone and 'Nikon FC-E9' fisheye lens used with Nikon Coolpix8700 are compared based on equidistant model. This experimental study shows that Olloclip 3 in one fisheye lens developed for mobile phones has at least the similar characteristics with classic fisheye lenses. The dimensions of fisheye lenses used with smart phones are getting smaller and the prices are reducing. Moreover, as verified in this study, the accuracy of fisheye lenses used in smartphones is better than conventional fisheye lenses. The use of smartphones with fisheye lenses will give the possibility of practical applications to ordinary users in the near future.
Nowadays, mobile phones are more than a device that can only satisfy the communication need betwe... more Nowadays, mobile phones are more than a device that can only satisfy the communication need between people. In addition to providing ease to human lives with various applications, lens kits that can be integrated to mobile phones have recently been introduced. Fisheye lenses that are compliant with mobile phones are one of these new types of equipment. Since fisheye lenses integrated with mobile phones are lightweight and easy to use, they are advantageous. In addition to this advantage, whether fisheye lens and mobile phone combination can be used in a photogrammetric way is experimented, and if so, what will be the result. The main purpose of this study is to test fisheye lens equipment used with mobile phones. In this study, standard calibration of “Olloclip 3 in one” fisheye lens used with iPhone 4S mobile phone and “Nikon FC-E9” fisheye lens used with Nikon Coolpix8700 are compared based on equidistant model. The results of these calibrations are analyzed, using photogrammetric...
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