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Article NEW TURKISH BORROWS LAW ON THE FRAMEWORK OF COMPETITOR PORTER(Istanbul Univ, Fac Law, 2014) Suzek, Sarper[No Abstract Available]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.Book Part A Simulation Environment for Cybersecurity Attack Analysis Based on Network Traffic Logs(inst Engineering Tech-iet, 2019) Daneshgadeh, Salva; Oney, Mehmet Ugur; Kemmerich, Thomas; Baykal, NazifeThe continued and rapid progress of network technology has revolutionized all modern critical infrastructures and business models. Technologies today are firmly relying on network and communication facilities which in turn make them dependent on network security. Network-security investments do not always guarantee the security of organizations. However, the evaluation of security solutions requires designing, testing and developing sophisticated security tools which are often very expensive. Simulation and virtualization techniques empower researchers to adapt all experimental scenarios of network security in a more cost and time-effective manner before deciding about the final security solution. This study presents a detailed guideline to model and develop a simultaneous virtualized and simulated environment for computer networks to practice different network attack scenarios. The preliminary object of this study is to create a test bed for network anomaly detection research. The required dataset for anomaly or attack detection studies can be prepared based on the proposed environment in this study. We used open source GNS3 emulation tool, Docker containers, pfSense firewall, NTOPNG network traffic-monitoring tool, BoNeSi DDoS botnet simulator, Ostinato network workload generation tool and MYSQL database to collect simulated network traffic data. This simulation environment can also be utilized in a variety of cybersecurity studies such as vulnerability analysis, attack detection, penetration testing and monitoring by minor changes.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.Article Citation - WoS: 14Citation - Scopus: 14Analysis of Temperature-Dependent Forward and Leakage Conduction Mechanisms in Organic Thin Film Heterojunction Diode With Fluorine-Based Pcbm Blend(Springer, 2020) Yildiz, D. E.; Gullu, H. H.; Toppare, L.; Cirpan, A.The forward and reversed biased current-voltage behaviors of the organic diode were detailed in a wide range of temperatures. In this diode, a donor-acceptor-conjugated copolymer system was constructed with poly((9,9-dioctylfluorene)-2,7-diyl-(2-dodecyl-benzo[1,2,3]triazole)) as a partner of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM). Two-order of magnitude rectification ratio was achieved, and the temperature-dependent values of saturation current, zero-bias barrier height, and ideality factor were extracted according to the thermionic emission model. The temperature responses of these diode parameters showed an existence of inhomogeneity in the barrier height formation. As a result, the observed non-ideal behavior was explained by Gaussian distribution of barrier height where low-barrier regions are effective in the forward biased conduction mechanism at low temperatures. Together with this analysis, series resistances were evaluated using Cheung's functions and also density of interface states were investigated. On the other hand, reverse biased current flow was found under the dominant effect of Poole-Frenkel effects associated with these interfacial traps. The reverse current conduction mechanism was detailed by calculating characteristic field-lowering coefficients and barrier height values in the emission process from the trapped state in the range of temperatures of interest.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.Article Citation - WoS: 14Citation - Scopus: 15Yielding of Two-Layer Shrink-Fitted Composite Tubes Subject To Radial Pressure(Springer Heidelberg, 2005) Eraslan, AN; Akis, TYielding of two-layer shrink-fitted composite tubes with axially constrained ends subject to either internal or external pressure is investigated in detail. In the framework of small deformations, a state of plane strain and von Mises yield criterion, analytical expressions are obtained for critical values of the pressure leading to plastic flow. It is shown that, depending on material properties and tube dimensions, different modes of plastic deformation may occur. Yielding may commence at the inner tube or at the outer tube or simultaneously in both tubes. The conditions for different nature of plastic flow are determined. Using analytical expressions obtained for critical values of the parameters and properties of real engineering materials, various numerical examples are handled and the variation of elastic limit pressure with interference and interface radius is explained.Article Citation - WoS: 7Computation of a Tunable Slot-Loaded Equilateral Triangular Microstrip Antenna(Vsp Bv, 2009) Aydin, E.In this paper, a simple closed form expression is developed to accurately estimate the lower and upper operating frequencies of a single feed slot loaded triangular patch (SLTP) with variations of the bent slot lengths. It is obtained by using cavity model analysis and useful to antenna engineers for accurately predicting both operating resonant frequencies of the SLTP. The theory is compared with the experimental results available in the literature, and excellent agreement is observed. The proposed computation is also extended to the analysis of tunability of the SLTP as a function of the air-gap height.Article Citation - WoS: 9Citation - Scopus: 9Urinalysis of Individuals With Renal Hyperfiltration Using Atr-Ftir Spectroscopy(Nature Portfolio, 2022) Kurultak, Ilhan; Sarigul, Neslihan; Kodal, Nil Su; Korkmaz, FilizAbnormal increased glomerular filtration rate (GFR), otherwise known as renal hyperfiltration (RHf), is associated with an increased risk of chronic kidney disease and cardiovascular mortality. Although it is not considered as a disease alone in medicine today, early detection of RHf is essential to reducing risk in a timely manner. However, detecting RHf is a challenge since it does not have a practical biochemical marker that can be followed or quantified. In this study, we tested the ability of ATR-FTIR spectroscopy to distinguish 17 individuals with RHf (hyperfiltraters; RHf (+)), from 20 who have normal GFR (normofiltraters; RHf(-)), using urine samples. Spectra collected from hyperfiltraters were significantly different from the control group at positions 1621, 1390, 1346, 933 and 783/cm. Intensity changes at these positions could be followed directly from the absorbance spectra without the need for pre-processing. They were tentatively attributed to urea, citrate, creatinine, phosphate groups, and uric acid, respectively. Using principal component analysis (PCA), major peaks of the second derivative forms for the classification of two groups were determined. Peaks at 1540, 1492, 1390, 1200, 1000 and 840/cm were significantly different between the two groups. Statistical analysis showed that the spectra of normofiltraters are similar; however, those of hyperfiltraters show diversity at multiple positions that can be observed both from the absorbance spectra and the second derivative profiles. This observation implies that RHf can simultaneously affect the excretion of many substances, and that a spectroscopic analysis of urine can be used as a rapid and non-invasive pre-screening tool.Conference Object Improvement of Mechanical Performance in Different Concrete Applications Through Use of Steel Fibers(International Committee of the SCMT conferences, 2016) Baran,E.; Mertol,H.C.; Akis,T.The use of steel fibers improves the brittle characteristics of concrete and provides superior mechanical performance compared to the conventional concrete. Remarkable increase in tensile strength and flexural toughness is obtained when steel fibers are used in conventional concrete, mainly due to the crack arrest effect of these fibers. The use of waste materials, such as scrap tires as a source of steel fibers, as well as the resulting increase in service life and the savings in the life cycle cost make the steel fiber reinforced concrete (SFRC) a sustainable construction material. From this perspective, SFRC offers a strong potential for a more sustainable and more economical alternative to conventional concrete. This paper presents examples of how the addition of steel fibers improves the mechanical performance in two different concrete applications: (1) bond behavior of prestressing strands and (2) flexural behavior of reinforced concrete beams. The first part of the study aimed at investigating the variation in bonding mechanism of prestressing strands when used in plain concrete and in SFRC. Pullout tests were conducted on 12.7 mm diameter prestressing strands embedded in SFRC blocks with four different fiber concentrations. This way, the applicability of the available transfer length and development length formulas for prestressing strands embedded in SFRC was investigated. In the second part of the study, flexural behavior of SFRC beams with various levels of flexural reinforcement ratio was studied. The aim was to identify the influence of steel fibers on the mechanical response of lightly and relatively heavily reinforced SFRC beams. The response of SFRC beams and the companion plain concrete beams were evaluated based on the moment capacity, deformation capacity, and service stiffness. © 2016 International Committee of the SCMT conferences. All rights reserved.
