Papers by RAMAZAN GÜRSEL HOŞBAŞ
KSCE Journal of Civil Engineering
Geodetski List, 2009
The multipath is a serious of error source in both the static and the kinematic GPS measurements.... more The multipath is a serious of error source in both the static and the kinematic GPS measurements. The positioning accuracy is being degraded due to multipath signal. The multipath detection depends on the difference of carrier to noise (C/NO) between the reference station and the rovers. It is focused on signal strength fading due to reflection and masking by surrounding objects such as trees and buildings. This paper shows the method to detect multipath and the example to improve the positioning accuracy by using the L1 signal processing in the different multipath environments.
Geodesy and Cartography, 2019
Applications in geodesy and engineering surveying require the determination of the heights of the... more Applications in geodesy and engineering surveying require the determination of the heights of the vertical control points in the national and local networks using different techniques. These techniques can be classified as geometric, trigonometric, barometric and Global Positioning System (GPS) levelling. The aim of this study is to analyse height differences obtained from these three techniques using precise digital level and digital level, total station (trigonometric levelling) and GPS which collects phase and code observations (GPS levelling). The accuracies of these methods are analysed. The results obtained show that the precise digital levelling is more stable and reliable than the other two methods. The results of the three levelling methods agree with each other within a few millimetres. The different levelling methods are compared. Geometric levelling is usually accepted as being more accurate than the other methods. The discrepancy between geometric levelling and short ra...
Bu calismada, 16. yuzyilin sonlarinda biri doguda digeri ise batida yer alan iki rasathane ve bur... more Bu calismada, 16. yuzyilin sonlarinda biri doguda digeri ise batida yer alan iki rasathane ve burada gorev yapmis bulunan iki onemli astronomi alimi ele alinmistir. Doguda Osmanli Imparatorlugunun yukselme doneminin son yillarinda payitaht Istanbul’da kurulmus Rasathane ve Italyan ronesansinin yeserttigi ortamda gelisen Danimarka’daki Hven Adasi’ndaki Uranibourg Rasathanesi tanitilmistir. Bu rasathanelerde gorev yapan sirasiyla Takiyuddin ve Tycho Brahe’nin hayatlari anlatilmistir. Ardindan, yuzyilin son ceyreginin basinda 1577’de bu iki rasathane tarafindan gozlenen bir kuyruklu yildizin dogu ve bati toplumlari tarafindan nasil algilandigi irdelenmistir. Dunyanin farkli bolgelerinde de gozlenen bu kuyruklu yildizin aslinda ayni gok cismi oldugunun kim tarafindan belirlendigi aciklanmistir. Sonuc olarak, o donemde rasathanelerin kaderi ele alinarak her iki toplumda bilime nasil yaklasildigi anlasilmaya calisilmistir.
The multipath is a serious of error source in both the static and the kinematic GPS measurements.... more The multipath is a serious of error source in both the static and the kinematic GPS measurements. The positioning accuracy is being degraded due to multipath signal. The multipath detection depends on the difference of carrier to noise (C/NO) between the reference station and the rovers. It is focused on signal strength fading due to reflection and masking by surrounding objects such as trees and buildings. This paper shows the method to detect multipath and the example to improve the positioning accuracy by using the L1 signal processing in the different multipath environments.
Nacrtak Until the mid-1990s, post-processing was the only method available to determine survey-gr... more Nacrtak Until the mid-1990s, post-processing was the only method available to determine survey-grade positions using GPS. A new method was then introduced called Real-Time Kinematic (RTK). Real Time Kinematic surveying is an advanced form of relative GPS carrier phase surveying in which the base station transmits its raw measurement data to rovers, which then compute a vector baseline from the base station to the rover. RTK GPS shows a really efficient and fast improvement within today’s technological developments. The most important reason for using it is that this technique enables obtaining coordinates instantaneously and in the centimeter level accuracy. This technique is widely used in construction and survey applications because of its above mentioned properties. The aim of this paper is to evaluate the repeatability of RTK measurement accuracy under different satellite configurations near/in forest and unobstructed environments. Testing was performed by using GPS+GLONASS rece...
Gunumuzde yeraltindaki madenleri kesfetmek amacli yapilan, sinyal gonderilerek yansiyan bu sinyal... more Gunumuzde yeraltindaki madenleri kesfetmek amacli yapilan, sinyal gonderilerek yansiyan bu sinyaller uzerinden yapilan yorumlama analiz calismalarina sismik calisma adi verilir. Sismik Yansima Yontemi, yapay sekilde uretilen sismik enerjinin yer icinde sismik dalgalar seklinde yansimasi, tabaka ara yuzeylerinden yansimasi ve kayit edilen yansimalarin sinyal analiz tekniklerine gore islenip yeraltini gosteren sismik kesitler haline getirilmesidir. Sismik yansima yontemi gunumuzde cesitli amaclar icin kara ve denizde uygulanmakla birlikte en onemli uygulama alani petrol ve dogalgaz kaynaklarinin bulunmasidir. Sismik Yansima Yontemi iki boyutlu veya uc boyutlu seklinde uygulanabilir. Iki boyutlu sismik uygulamalarda sadece bir alici kablosu kullanilir. Bir hat boyunca toplanan sismik verilerden veri-islem sonrasinda yeraltini gosteren sismik kesitler elde edilir. Uc boyutlu sismik uygulamalarda birden fazla alici kablosu ve birden fazla sismik kaynak kullanilir. Sismik veriler yeraltin...
Ömer Halisdemir Üniversitesi Mühendislik Bilimleri Dergisi
Arazi bölümlendirmeleri ve parsel kırık sınırlarının düzeltilmesinde son zamanlara kadar uygulana... more Arazi bölümlendirmeleri ve parsel kırık sınırlarının düzeltilmesinde son zamanlara kadar uygulanan yöntemler genellikle sınama esasına dayanmaktadır. Bu durum, normal olarak geometrik ve trigonometrik elemanların hesaplanmasını gerektirir. Bu çalışmada herhangi bir parsel şekline bağlı olmaksızın uygulanabilecek genel formüller verilmektedir. Böylelikle bölümlendirme sonuçlarını elde etmek mümkün olmaktadır. Bu yöntem arazideki parsellerin dik koordinat sistemindeki koordinatlarını esas almaktadır. Bölümlendirme, belirli bir alanın ayrılmasını ve bölümlendirme çizgisinin istenen bir yerden geçirilmesini sağlamaktadır. Böyle üç gereksinim düşünülebilir; bölümlendirme çizgisinin bir uç noktası sabit olabilir, çizginin yönü sabit olabilir veya çizginin bilinen bir iç noktadan geçmesi istenebilir, [1]. Bunlara ilaveten bazı teknik ve ekonomik gerekçelerle kırık parsel sınırlarının da düzeltilmesi gerekmektedir. Bazı özel durumlar için, yöntem formüller uygulamadan önce dik koordinat eksenlerinin döndürülmesini gerektirmektedir. Sunulan çalışmada, iki uygulama verilerek yöntemin sonuçlarının uygunluğu gösterilmiştir.
Tehnicki vjesnik - Technical Gazette
One of the important indicators of developed societies, protect their history and transport them ... more One of the important indicators of developed societies, protect their history and transport them for future generations. Therefore, sustainable monitoring and determination present situations of the historical buildings are important for protection of them. Knowledge and awareness of these structures in terms of absolute positional and dimensional information acquisition, evaluation and analysis associated with geomatic engineering. In this context, it is aimed to monitor the existing structural deformations of barrack located in Davutpasa Campus at Yildiz Technical University, for two hundred years, using modern geodetic techniques. In this study, geodetic network, has fixed and dynamic points, established to monitor horizontal and vertical deformations occurred in the southern-east facade of barrack. Mentioned network consists of 5 reference points and 10 traverse points. Six of polygons inside of the structure and the remaining 4 polygons are out of it. The structure has 54 object points, 28 of them are based inside the structure and the remaining 26 object point of them out of it. These points are based in a form of on the wall to determine the deviations from vertical plane and also the points in a form of a pair of points are based on the wall with same vertical direction. Since the date of June 2011, the structure measured for three periods by terrestrial and satellite observation techniques. The displacements observed during three periods of measurement. Horizontal positions of 5 fixed points are measured by satellite observation techniques. Also terrestrial measurements were made depending on 5 fixed points as mentioned above to determine the 10 polygon point's horizontal position. Horizontal positions of the object points are measured by distance/angle surveying technique and calculate their coordinates with resection method depend on polygons. Vertical displacement of 15 fixed points measured by precise geometric levelling method and horizontal displacement of 54 object points measured by precise trigonometric method. In this study, design of geodetic control network, measurements, evaluation and analysis first results are given.
Šumarski list
A GNSS involves a constellation of satellites orbiting Earth, continuously transmitting signals t... more A GNSS involves a constellation of satellites orbiting Earth, continuously transmitting signals that enable users to determine their three-dimensional (3D) position with global coverage. The positioning principle is based on solving an elemental geometric problem, involving the distances (ranges) of a user to a set of at least 4-5 GNSS satellites with known coordinates. These ranges and satellite coordinates are determined by the user’s receiver using signals and navigation data transmitted by the satellites; the resulting user coordinates can be computed to an accuracy of several metres. However, centimetre-level positioning can be achieved using more advanced techniques (kinematic). GPS/GLONASS technique is becoming compulsory for many applications concerning forest management and inventory. This paper aims to comparing the coordinates resulted from Post Process Kinematic with the resulted coordinates for the same points resulted from static technique. Nonetheless, it appears that...
Uploads
Papers by RAMAZAN GÜRSEL HOŞBAŞ