Abstract. The main purpose of this study is to investigate the possibilities of monitoring crustal movement, during collective evaluation of first-and second-order GPS densification networks. The new criteria, which are independent from the network datum, are widely used for the evaluation and quality processing of geodetic networks. In this study, the values of detectable minimum displacement for a real GPS network are investigated as well as how sensitivity levels are affected by additional datum conditions, which are added to the adjustment model.

An optimization strategy based on head losses minimization is developed for the least cost design of water distribution networks. A new weighting approach is suggested for calculating the initial flow distribution and optimum pipe diameters of the weighted flow distribution is presented by using least square method. In the mean time homogenous and isotropous head losses are maintained with implications of head loss path choice. The model is employed for designing and/or modifying pipe sizes while the classical HardyCross network solver is used to balance the flows. The whole algorithm is programmed and applied to a two-looped network selected from the literature and the results are presented on a comparative basis. A FORTRAN software with the necessary steps in the flow chart is written for the optimization calculations in this paper.

Geodetic Networks designed as Deformation Networks or Continuous Networks are observed in different epochs/ sessions and evaluated as a function of time. Those can be design as global GNSS networks for aim monitoring active tectonic movements or as regional densification geodetic and deformation networks for monitoring local earthquakes and surface movements. The areas covered geodetic networks are assumed as any surface on ellipsoid or sphere. Characteristics of surfaces are analyzed with Geometric Strain Models using deformation data on surface points. In this case, effect rates on geodetic network area are determined from local surface movements or regional active earthquakes and interpreted as experimental. On the other hand, undetermined outliers by model hypothesis test affect coordinateunknowns separately. Outliers cause deformations in certain magnitude on networks points. Therefore, network points strain in different rates and directions. Query of maximum affects caused by these strain rates is a referenced reliability method called "Robustness Analysis in Geodetic Networks". Mentioned strain rates are modelled by various estimation methods. Thus, deformation results could be interpreted together by the obtained strain components and deformation vector. In this paper, possible strain components belonging to network points are determined with methods of L1 Norm, Least Median Squares (LMS) and Least Squares Estimation (LSE). These estimation methods are tested on KOUSAGA (Kocaeli University Permanent GPS Network). Strain components are estimated by use polyhedrons covered by network points. Obtained results are compared and analyzed according to weakness and strengths of proposed estimation methods.

ÖzYerkabuğu hareketleri doğal gaz, ulaşım, iletişim enerji vb yasamsal alt yapı sistemlerini olumsuz yönde etkilerler. Bu nedenle ekonomik değeri yüksek olan, kamu hizmetleri kapsamındaki yaşamsal altyapı sistemleri jeodezik kontrol noktaları/ağları yardımıyla düzenli aralıklarla izlenmeleri gerekli ve zorunludur.Bu çalışmada, bilimsel amaçlı bir araştırma projesi kapsamında izlenmekte olan Kocaeli İZDOGAP Sıklaştırma GPS Ağı, gerçek bir yaşamsal altyapı izleme sistemi olarak seçilmiştir. Belli aralıklarla izlenmekte olan İZDOGAP GPS Ağı'ndan elde edilen konum ve hız bilgileri kullanılarak; bölgede olası yıllık yer kabuğu hareketlerini algılayabilme düzeyi ve bu ağı temsil eden bölgesel gerinim parametreleri irdelenmektedir. Elde edilen deneysel bulgular matematik/istatistik modellerle yorumlanmakta, sonuçlar karşılaştırmalı olarak sergilenmektedir.Anahtar Kelimeler: Algılayabilirlik, Hız Alanı, Gerinim, Jeodezik Ağlar. Monitoring of Lifeline Systems with Densification GPS Networks and Interpretation of deformations: Application of Kocaeli IZDOGAP GPS Network AbstractEarth crustal movements affect negatively Lifeline systems such as natural gas, electrical power, communication and transportation facilities. Therefore Lifeline systems with high economic value must be monitored temporal with geodetic networks.In this study, the Kocaeli İZDOGAP Densification GPS Network monitored within the scope of a scientific research project is selected as a real lifeline monitoring system. The sensitivity level of possible annual crustal movements in the region and regional strain parameters of the network are analysed by using position and velocity values of IZDOGAP GPS Network. The experimental findings obtained are interpreted with mathematical / statistical models and the results are presented comparatively.

The geodetic networks should be able to detect the possible earth crust movements caused by active tectonic movements in Turkey. Geodetic networks should also be able to determine the crust movements accurately as well as provide precision and reliability requests. The capacity of geodetic networks to determine the crustal movements can be determined by sensitivity analysis. Robustness analysis consists of strengthening internal reliability analysis with strain techniques. Robustness is defined as the deformation strength induced by the maximum undetectable errors with the internal reliability analysis. The robustness of a geodetic network is determined by the global initial condition, which aims at minimizing the total displacement value in the network. In this study, the local initial condition that aims to minimize the total displacement value at the uniform polyhedron, which consists of observations from each station points. The displacement values obtained according to the local and the global initial conditions are compared with threshold values. The results have also been interpreted.