Alkan Günlü

Prof. Dr. Alkan Günlü


Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 February 2008 in Environmental Monitoring and Assessment
Verified
Journal Article
Closed access
PDF file
AGAlkan Günlü
Alkan Günlü
AKAli Ihsan Kadıoğulları
Ali Ihsan Kadıoğulları
SKSedat Keleş
Sedat Keleş
Emin Zeki BASKENTEmin Zeki BASKENT
Emin Zeki BASKENT

20 September 2018 in Geocarto International
Verified
Journal Article
Closed access
AGAlkan Günlü
Alkan Günlü
IEIlker Ercanli
Ilker Ercanli
The goal of this study was to estimate aboveground stand carbon (AGSC) of pure beech stands in Turkey with ground measurements as well as topographic information and remote sensing data. For this purpose, 153 sample plots were collected from pure beech stands in study area. The AGSC of each sample plot was computed. Eight texture images (variance, dissimilarity, homogeneity, entropy, contrast, mean, second moment and correlation) with five window sizes (3 × 3, 5 × 5, 7 × 7, 9 × 9 and 11 × 11) generated from ALOS PALSAR L-band satellite image. The AGSC models predicting the relationships between ALOS PALSAR texture values and topographic information, and sample plot AGSC were developed by using multiple linear regressions (MLR). Also, artificial neural networks (ANNs) architectures were trained by comparing various numbers of neurons and activation functions in its network types. Our results revealed the ability of ANNs was better than MLR models to predict AGSC values.

22 May 2008 in Environmental Monitoring and Assessment
Verified
Journal Article
Closed access
PDF file
AGAlkan Günlü
Alkan Günlü
Emin Zeki BASKENTEmin Zeki BASKENT
Emin Zeki BASKENT
AKAli Ihsan Kadıoğulları
Ali Ihsan Kadıoğulları
LALokman Altun
Lokman Altun

1 January 2014 in European Journal of Remote Sensing
Verified
Journal Article
Open access
AGAlkan Günlü
Alkan Günlü
IEIlker Ercanli
Ilker Ercanli
TSTuran Sönmez
Turan Sönmez
Emin Zeki BASKENTEmin Zeki BASKENT
Emin Zeki BASKENT

9 April 2008 in Sensors
Verified
Journal Article
Open access
PDF file
AGAlkan Günlü
Alkan Günlü
FSFATIH SIVRIKAYA
FATIH SIVRIKAYA
Emin Zeki BASKENTEmin Zeki BASKENT
Emin Zeki BASKENT
SKSedat Keles
Sedat Keles
GÇGünay Çakir
Günay Çakir
AKAli Ihsan Kadıoğulları
Ali Ihsan Kadıoğulları
Remote sensing has been considered a low-cost, large-area coverage forest information resource ideally suited to broad-scale forest inventory objectives. The objective of this study is to determine stand type parameters such as crown closure, development stage and stand types, and land cover obtained from Landsat 7 ETM image and forest cover type map (stand type map). The research also focuses on classifying and mapping the stand parameters with the spatial analysis functions of GIS. In the study, stand parameters determined by forest cover type map and remote sensing methods were compared and contrasted to evaluate the potential use of the remote sensing methods. The result showed that development stage were estimated with Landsat 7 ETM image using supervised classification with a 0.89 kappa statistic value and 92% overall accuracy assessments. Among the features, development stages were the most successfully classified stand parameters in classification process. According to the spatial accuracy assessment results, development stages also had the highest accuracy of 72.2%. As can be seen in the results, spatial accuracy is lower than classification accuracy. Stand type had the lowest accuracy of 32.8. In conclusion, it could be stated that development stages, crown closure and land cover could be determined at an acceptable level using Landsat 7 ETM image. However, Landsat 7 ETM image do not provide means to map and monitor minor vegetation communities and stand types at stand level due to low spatial resolution. High resolution satellite images could be used either alone or with field survey data.

15 April 2023 in Bartın Orman Fakültesi Dergisi
Verified
Journal Article
Open access
PDF file
IGİzZet Güverçi̇n
İzZet Güverçi̇n
AGAlkan Günlü
Alkan Günlü
Bu çalışmanın amacı; saf kızılçam (Pinus brutia Ten.) meşcrelerinde aktif (Sentinel-1A) ve pasif (Landsat 8 OLI) uydu görüntüleri ile bazı topoğrafik veriler kullanılarak topraküstü biyokütlenin tahmin edilmesidir. Çalışmada toplam 404 adet örnek alan verisi kullanılmıştır. Bu örnek alan verilerinin 323 (%80) modellerin oluşturulmasında ve 81 (%20) ise modellerin test edilmesinde kullanılmıştır. Her bir örnek alana ilişkin topraküstü biyokütle değerleri allometrik denklem kullanılarak hesaplanmıştır. Ayrıca her bir örnek alana ilişkin Landsat 8 OLI uydu görüntüsünden bant reflektans, vejetasyon indis ve tekstür değerleri, Sentinel-1A uydu görüntüsünün her iki polarizasyonu (VV ve VH) için parlaklık ve geri yansıtım değerleri ile Alos-Palsar uydu görüntüsünden üretilen Sayısal Yükseklik Model (SYM) verisinden yükselti, eğim ve bakı değerleri hesaplanmıştır. Topraküstü biyokütle ile Landsat 8 OLI, Sentinel-1A ve SAM verisinden elde edilen değişkenler arasındaki ilişkiler regresyon analizi ile modellenmiştir. Toplam 22 farklı regresyon modeli geliştirilmiştir. Geliştirilen modeller arasında en iyi ilişki (R2= 0,509 ; Sy.x= 28,39), Landsat 8 OLI uydu görüntüsünün bant reflektans değerleri, vejetasyon indisleri, tekstür değerleri, Sentinel-1A uydu görüntüsünün iki polarizasyona ilişkin parlaklık değerleri ile yükselti ve bakının bağımsız değişkenler olarak yer aldığı modelle elde edilmiştir.