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Conference Object Citation - Scopus: 2Effect of Discontinuity Orientation and Spacing on the Blasting Performance in Some Open Cast Mines of Tki-Turkey(International Society for Rock Mechanics, 2003) Kaçar,G.; Özgenoglu,A.; Bilgin,H.A.In this study, the influences of rock mass properties on the blasting performance in open cast mines are investigated. To this end, discontinuity spacings and discontinuity orientations are measured and full scale blasts with various designs are observed in open cast mines of Aegean Lignite (ELI) and Bursa Lignite (BLI) Establishments belonging to Turkish Coal Enterprises (TKI). For each blast, blasting cost is calculated, and particle size distribution representing the fragmentation of muckpile is determined by means of Split-Desktop software using image processing. 50%(K50), 80%(K80) passing sizes and topsize values are used in the determination of blasting performance according to rock mass properties. The relationships between orientation angle, which is the acute angle between the strikes of slope face and major discontinuity, and 50%(K50) and 80%(K80) passing sizes and topsize values and also blasting cost are investigated in order to analyse the influences of major discontinuity orientation on fragmentation and blasting cost. Furthermore, the relationships between discontinuity modal spacing (or block size index) and 50%(K50) and 80%(K80) passing sizes and topsize values and also blasting cost are investigated in order to analyse the influences of discontinuity spacing on fragmentation and blasting cost. In this paper, the trends observed in these relationships are discussed and the importance of it in mining is commented. © 2003 10th ISRM Congress. All rights reserved.Conference Object Citation - WoS: 6Discrete calculus of variations(Amer inst Physics, 2004) Guseinov, GSThe continuous calculus of variations is concerned mainly with the determination of minima or maxima of certain definite integrals involving unknown functions. In this paper, a discrete calculus of variations for sums is treated, including the discrete Euler-Lagrange equation.Conference Object Bar code localization by image processing;(2005) Öktem,R.; Çetin,A.E.This paper addresses the problem of bar code recognition by use of image processing. Bar codes are composed of parallel alternating dark-light stripes; hence they also appear as parallel lines connected at some orientation in a binary edge map. The proposed algorithms exploit that feature and use morphology and free angle thresholding for localization. Edge map is formed by Sobel operator and binary subband decomposition separately, and the two methods are compared in terms of time complexity and performance. Detailed discussion of test results are also presented. ©2005 IEEE.Conference Object Citation - Scopus: 9A Layered Security Architecture for Corporate 802.11 Wireless Networks(Institute of Electrical and Electronics Engineers Inc., 2004) Erten,Y.M.; Tomur,E.In this study we have investigated the security aspects of wireless local area networks and discussed the weaknesses associated with various conventional 802.11 security protocols such as WEP and 802.1x. We propose an architecture to control access to corporate 802.11 wireless networks, based on the privileges and location of users, using the tested wired network components such as VPNs and Firewalls. The presented architecture reduces the security risks in enterprise level deployment of wireless LANs.Conference Object Citation - Scopus: 8Modeling-Error Based Adaptive Fuzzy Sliding Mode Control for Trajectory-Tracking of Nonlinear Systems(2003) Yu,S.; Yu,X.; Efe,M.O.A novel adaptive fuzzy sliding mode control design is developed for trajectory tracking of a class of nonlinear systems in this paper. This control design uses the modelling error to adaptively estimate the deterministic uncertainties as well as the control gain based on the fuzzy systems approach. By this design, the bounds of the uncertainties are not required to be known in advance, and the robust stability of closed loop systems is analysed in the Lyapunov sense. Simulation results are given to demonstrate the improved performance.Conference Object Citation - Scopus: 16Target Tracking Using Artificial Potentials and Sliding Mode Control(2004) Gazi,V.; Ordóñez,R.In this article we develop an algorithm for capturing/intercepting a moving target based on the sliding mode control method. First, we consider a "kinematic" model (in a sense) for the capture/intercept problem and develop a method for that case. Then, we build on the developed method to include general fully actuated vehicle dynamics for the pursuer agent. The algorithm is robust with respect to the system uncertainties and additive disturbances. Finally, we also provide a numerical simulation in order to illustrate the procedure.Conference Object Citation - Scopus: 3A simulation model for mine production sequences(2006) Aydiner,K.; Çelebi,N.; Paşamehmetoǧlu,A.G.Mine design process strictly dependent on the economical variables of the orebody and the rock mass properties having effect on the physical parameters of the intended mining system. In addition, the dynamic aspects of the possible system must be taken into account. Difficulty in design arises mainly from the difficulty in obtaining enough and reliable data. Collecting enough and quality data requires to costly and timely procedures. Therefore, the mine design engineers have to consider alternative cases in their designs or they have to design with limited data. This study presents a simulation model that can be used to develop the production subsystem model of an underground mining system. A mechanized production system model and a decision analysis tool using a discrete event simulation process were developed. The tool allows an engineer with experimenting his/her design to generate a model that can meet the targeted production rate.Conference Object Citation - Scopus: 3Design of Frp Retrofitted Flexural Members Against Debonding Failures(2006) Gunes,O.; Karaca,E.; Gunes,B.Use of fiber reinforced polymer (FRP) composites in seismic retrofitting of structural members has been steadily increasing in recent years. An important design issue with significant performance and safety implications is the debonding of externally bonded FRP reinforcement in flexural members. This paper provides the highlights of an experimental and analytical research aimed at understanding and modeling of debonding failures in FRP strengthened reinforced concrete beams. An evolutionary experimental program investigated debonding failure mechanisms and modes in beams strengthened in shear and/or flexure in various configurations and tested under monotonic and cyclic loading. A newly developed fracture mechanics based model considers the global energy balance of the system and predicts the debonding failure load by characterizing the dominant mechanisms of energy dissipation during debonding. Validation of the model is performed using experimental data obtained from several independent experimental studies.Conference Object Citation - Scopus: 1Ore-Age: an Intelligent Assisting and Tutoring System for Mining Method Selection(2003) Guray,C.; Celebi,N.; Atalay,V.; Gunhan,A.In the past studies about the mining method selection process, which is among the most critical aspects in the mining engineering discipline, there are attempts to build up a systematic approach to make this selection. But, these approaches work based on static databases and fail in inserting the intuitive feelings and engineering judgments of experienced engineers to the selection process. In this study, a hybrid system based on 13 different expert systems and one interface agent is developed, to make mining method selection for the given ore-bodies. The learning procedure to insert the expertise of the experienced engineers to the selection process, works based on a neuro-fuzzy model, combining the TSK model of the fuzzy theory and a two layered neural network with the utilization of the back-propagation algorithm. Again, to supply the maximum assistance to the users, the agent executes the system's tutoring procedure in case an inexperienced user enters the system, to complete his/her missing knowledge about mining method selection. The system that is being developed in this study can be introduced as the first example of dynamic, intelligent assisting and tutoring systems in the mining profession.Conference Object Citation - Scopus: 25Blockage/Shadowing and Polarization Measurements at 2.45ghz for Interference Evaluation Between Bluetooth and Ieee 802.11 Wlan(2001) Kara,A.; Bertoni,H.L.We present measurement results at 2.45 GHz to evaluate blockage shadowing and fading effects due to furniture and people next to terminals for short range indoor communication systems. The followings are the results: people crossing the link near to a terminal can cause fading up to 20dB which is more than furniture blockage measured of about 5-13dB depending on objects over the links, polarization coupling was also measured by using dual polarized antenna at receiving end, and coupling is higher for obstructed links, which suggests polarization diversity.
