Berkant Konakoglu

Amasya University · Architecture and Urban Planning

With the advent of unmanned aerial vehicles (UAVs) for mapping applications, it is possible to generate 3D dense point clouds using stereo images. This technology, however, has some disadvantages when compared to LiDAR (Light Detection and Ranging) system. Unlike LiDAR, digital cameras mounted on UAVs are incapable of viewing beneath the canopy, wh...

This paper investigates the behaviour of the double-curvature Deriner dam, which is in the operation phase and also one of the highest dams in the world. In order to determine the displacements, a geodetic network consisting of twelve reference and seven object points was measured in four periods by means of the Global Navigation Satellite Systems...

The prediction of an accurate geodetic point velocity has great importance in geosciences. The purpose of this work is to explore the predictive capacity of three artificial neu-ral network (ANN) models in predicting geodetic point velocities. First, the multi-layer perceptron neural network (MLPNN) model was developed with two hidden layers. The g...

In the present article, the efficiency of a new hybrid learning method, named artificial neural network with gradient‐based optimizer algorithm (ANN‐GBO), is investigated to determine a local geoid. The outcomes of the assessed method are compared with classical ANN (without GBO), some metaheuristic‐based ANN models and other study results (interpo...

In recent years, machine learning techniques, especially artificial neural networks (ANN), have been widely applied for engineering problems since they have proven to be a good predictor, especially in accurate weather forecasting applications. The study aims to evaluate the prediction capability of the novel hybrid ANN-GTO (Gorilla Troops Optimize...

Turkey is located in a region with a high density of fault lines, which makes it susceptible to a significant earthquake risk. The Kahramanmaraş earthquake on February 6, 2023, was one of the most devastating in recent years, causing extensive damage and loss. This study aims to support post-disaster rapid response and rescue operations by using de...

The selection of emergency assembly points within the urban area holds significant importance for ensuring swift and effective intervention in the aftermath of a potential disaster until temporary shelter areas are prepared. In both historical and instrumental periods, Erzincan (Türkiye) has experienced major earthquakes resulting in significant lo...

Unmanned Aerial Vehicles (UAVs) are widely acknowledged as an optimal technology owing to their exceptional capabilities in terms of time efficiency, precision, safety, and cost-effectiveness. As a result, there is a rapidly growing interest in this technology, which is now being utilized across various sectors, such as agriculture, forestry, se...

Forest environment and topographic obstacles tend to reduce the positioning performance of precise point positioning (PPP) with ambiguity resolution (AR) and may even prevent radio signals from reaching the global navigation satellite systems (GNSS) antenna. In this study, we investigated the positioning performance of PPP-AR in a forest environmen...

The selection of emergency assembly points within the urban area holds significant importance for ensuring swift and effective intervention in the aftermath of a potential disaster until temporary shelter areas are prepared. In both historical and instrumental periods, Erzincan (Turkey) has experienced major earthquakes resulting in significant los...

The Journal of Geodesy (JOGE) is acknowledged as a globally respected peer-reviewed journal in the domain of geodetic science and its related interdisciplinary fields. In recent years, there has been significant attention directed towards bibliometric analysis within the scientific community. As a result, we opted to conduct a bibliometric analysis...

GNSS teknolojisi, orman kaynaklarının araştırılması ve izlenmesi için güçlü bir araç haline gelmiştir. Ancak, ormanlık/ağaçlık alanlarda orman örtüsü GNSS sinyalleri ve uydu sayısı üzerinde olumsuz etkiye sahiptir. Bu yüzden hassas konum belirlemek mümkün olmayabilmektedir. Uydu jeodezisinde ve analiz tekniklerinde yaşanılan gelişmeler ile sadece b...

2022 Mw 6.0 Düzce depremi, 23 Kasım 2022 tarihinde Yerel Saatle 04:08'de Türkiye'ninDüzce ili Gölyaka İlçesi'nde meydana gelmiştir. Boğaziçi Üniversitesi Kandilli Rasathanesi veDeprem Araştırma Enstitüsü'nün (KOERI) verilerine göre, depremin merkez üssü yaklaşık 10.6km derinlikte 40.8175°K, 30.9868°D'de bulunmaktadır. Sarsıntı, 200 kilometre uzakta...

Bu çalışmada, orman ortamında tek bir GNSS alıcısı kullanılarak Hassas Nokta Konumlandırma (PPP) tekniğinin konum belirleme performansı araştırılmıştır. Bu kapsamda, Amasya Üniversitesi Yeşilırmak Kampüsünde ormanlık bir test alanı seçilmiş ve bu alanın tepe kapalılık haritası uzaktan algılama yöntemleriyle üretilmiştir. Statik GNSS ölçümleri (seki...

This study provides a comprehensive comparison of four different machine learning models including the group method of data handling (GMDH), M5 model tree (M5MT), multivariate adaptive regression spline (MARS), and Gaussian process regression (GPR) for predicting geoid undulation. For the first time, GMDH and M5MT were applied for this purpose. The...

Local geoid determination studies are commonly carried out today to establish the relationship between the ellipsoidal height (ℎ) determined by satellite geodesy methods and the orthometric height (𝐻) found using geoid undulation (𝑁) . The aim of this study was to determine a local geoid using the kriging, local polynomial (LP), and inverse distanc...

This study evaluated different methods for geoid undulation prediction and included two types of artificial neural networks (ANNs)-the radial basis function neural network (RBFNN) and the generalized regression neural network (GRNN)-as well as conventional methods including multiple linear regression (MLR) and ten different interpolation techniques...

With the developments in technology in recent years, it is known that the UAV (Unmanned Aerial Vehicle) photogrammetric map production technique is widely used in the photogrammetric mapping. The study aims to compare the effect of the positional accuracies of the orthophotos of Amasya University Hâkimiyet Campus produced using DJI Phantom 4 PRO UA...

Klasik nivelman ölçümleri ile mühendislik uygulamalarında kullanılan ortometrik yükseklikleri bulmak çok zor ve zaman alıcı olmasına rağmen, GNNS tekniği ile belirlenen elipsoid yüksekliklerden ortometrik yüksekliklere dönüşüm daha kolaydır. Ancak bu dönüşüm için jeoid ondülasyon değerlerinin kesin doğrulukla bilinmesi gerekir. Bu bağlamda bu çalış...

The transformation from geodetic coordinates to 3D Cartesian coordinates is very easy, whereas the transformation from 3D Cartesian to geodetic coordinates is a bit more difficult because of the mathematical relationship between the latitude and the 3D Cartesian coordinates. Numerous papers have been published in the geodetic literature describing...

Türkiye Ulusal Sabit GNSS İstasyonları Ağı-Aktif (TUSAGA-Aktif) projesi, KKTC ve Türkiye dâhil olmak üzere toplam 158 adet sabit istasyon ile kullanıcılarına hizmet vermektedir. Oluşturulan bu GNSS ağı yardımıyla depremlerin neden olduğu hareketler etkin bir şekilde belirlenebilmektedir. Doğu Anadolu Fay Zonu (DAFZ) üzerinde 04 Nisan 2019 (5.2 Mw),...

On October 30, 2020, at 14.51 (2.51 pm) (local time), a 16 kilometer-depth earthquake, whose instrumental magnitude was Mw 6,6 (AFAD - Disaster and Emergency Management Presidency), Mw 6,9 (BU – Boğaziçi University Kandilli Observatory and Earthquake Research Institute), occurred between the north of Samos Island and the coast of Doğanbey, İzmir in...

To serve the purpose of their establishment in a beneficial way, dams should be monitored periodically by geodetic or geotechnical methods. To this aim, in this study, geodetic deformation monitoring was conducted on the Deriner Dam, Turkey’s highest double–curvature concrete arc dam. The GNSS measurements were taken within 4 campaigns between the...

In order to convert ellipsoidal heights obtained by the Global Navigation Satellite System (GNSS) to orthometric heights, it is necessary to know the distance between the ellipsoidal and geoid surface, called the geoid undulation. The geoid undulation can be predicted using emerging mathematics tools and algorithms. The objective of this study was...

This study aimed to determine the most suitable local geoid model based on 641 GNSS/leveling points within the borders of Kars Province in eastern Turkey using the generalized regression neural network (GRNN), weighted average (WA), multiquadric (MQ), inverse multiquadric (IMQ) function, and local polynomial (LP) method. Among these methods used in...

Determining orthometric heights used in engineering applications by geometric leveling is a very difficult and time-consuming process. It is easy to transform ellipsoidal heights determined from Global Positioning System (GPS) measurements to orthometric heights. However, an assured degree of accuracy is very important in determining a geoid model...

TUSAGA-Aktif (Türkiye Ulusal Sabit GNSS Ağı-Aktif) sistemi, Türkiye Cumhuriyeti ve KKTC’ ye yerleştirilen 158 adet sabit GNSS (Global Navigation Satellite System) istasyonu ile, ticari ve akademik çalışmalar için kullanıma sunulmuştur. 24 Ocak 2020 tarihinde Doğu Anadolu Fay Zonu (DAFZ) üzerinde Sivrice-Elazığ merkezli saat 20:55’ de (lokal zaman)...

Jeodezik elipsoidal koordinatlar (φ, λ, h) ile üç boyutlu (3B) global kartezyen koordinatlar (X, Y, Z) arasındaki dönüşüm işlemi sıklıkla karşılaşılan bir problemdir. Bu dönüşüm problemini çözmek için sadece bir yöntem bulunmuştur. Mevcut araştırmalar incelendiğinde jeodezik elipsoidal koordinatlardan 3B global kartezyen koordinatlara dönüşüm yönte...

Civil engineering structures (e.g., bridges, dams) are exposed to deformation under the influence of various factors such as water level changes, landslides, tectonic phenomena, etc. These deformations must be periodically monitored. Various deformation analysis approaches have been developed to describe the behaviour of a structure or natural proc...

Yapım maliyeti oldukça yüksek olan barajlar, barajın kendi ağırlığı, sıcaklık değişimi ve su yükü gibi iç ve dış faktörlerden dolayı deformasyona maruz kalırlar. Bahsi geçen faktörler karşısında yapısal davranışın ne kadar etkilendiği izlenmeli, varsa hareketlerin belirlenmesi ve barajların güvenlikleri sağlanmalıdır. Barajların kurulum amaçlarına...

The coordinate transformation has always been a hot topic in the field of geodesy. The artificial neural network (ANN) has been used as an alternative tool to determine the relationship between any two coordinate systems. Construction of an effective neural network depends on the network architecture, learning parameters and normalization technique...

To serve the purpose of their establishment in a healthy way, dams should be monitored periodically by geodetic or geotechnical methods. For this aim, in this thesis, geodetic deformation monitoring was conducted on the Deriner Dam, Turkey's highest double-curvature concrete arch dam, based on the GNSS measurements made within four periods between...

A digital elevation model (DEM), an important source of data for terrain-based analysis, used in many fields such as hydrology, geology and cartography. The aim of this study is to examine the performance of three different training algorithms for predicting the heights on a DEM. Levenberg-Marquardt Backpropagation (LM), Bayesian Regularization Bac...

Coordinate transformation is an important subject for geodesy, surveying, photogrammetry, GIS, cadastral and other related professions. A large number of one-dimensional (1D), two-dimensional (2D) and three-dimensional (3D) transformations have been proposed and conducted using conventional techniques such as similarity, affine, projective and poly...

Dams, one of the country's most natural and cheapest way to product energy, are built for energy production, agricultural activities and flood protection. Dams with high construction costs are subject to deformation due to some physical factors. Therefore, dams should be kept safe to prevent possible dam accidents, loss of life and property. Engine...

The purpose of this work is to evaluate the vertical movements of the Deriner dam based on periodic conventional geodetic measurement campaigns conducted starting from the first filling of the reservoir. The Deriner dam, which is a double-curvature concrete arch, is the highest in Turkey with a body height of 249 m. Conventional geodetic measuremen...

Dams are among the most significant energy sources in today's world. Hence, it is vital to maintain their sustainability. Geodetic and non-geodetic techniques are used to investigate the deformations of the dams periodically and to prevent any possible dam accidents, loss of life and property. This study aims at investigating the horizontal movemen...

One of such transformation methods, the two-dimensional similarity transformation, is widely used in geodetic studies. The outliers in the measure group should be detected so that the model established during the transformation process gives accurate results. In transformation practices, conventional outlier detection test procedures based on the l...

Two coordinate systems used in Turkey, namely the ED50 (European Datum 1950) and ITRF96 (International Terrestrial Reference Frame 1996) coordinate systems. In most cases, it is necessary to conduct transformation from one coordinate system to another. The artificial neural network (ANN) is a new method for coordinate transformation. One of the big...

Two coordinate systems used in Turkey, namely the ED50 (European Datum 1950) and ITRF96 (International Terrestrial Reference Frame 1996) coordinate systems. In most cases, it is necessary to conduct transformation from one coordinate system to another. The artificial neural network (ANN) is a new method for coordinate transformation. One of the big...

In this study, Karadeniz Technical University campus has been selected as study area. Monthly average values of the number of clear sky days, air temperature, atmospheric pressure, relative humidity, sunshine duration and solar radiation parameters obtained for the years between 2005 and 2015 will be used to perform artificial neural network analys...

INVESTIGATION OF GEODETIC TRANSFORMATION METHODS AND DEVELOPING THEIR SOFTWARES