Browsing by Subject "Computer hardware"

Now showing 1 - 4 of 4

Open Access
Hardware accelerator design for data centers
(IEEE, 2016-11) Yeşil, Şerif; Özdal, Muhammet Mustafa; Kim, T.; Ayupov, A.; Burns, S.; Öztürk, Özcan.
As the size of available data is increasing, it is becoming inefficient to scale the computational power of traditional systems. To overcome this problem, customized application-specific accelerators are becoming integral parts of modern system on chip (SOC) architectures. In this paper, we summarize existing hardware accelerators for data centers and discuss the techniques to implement and embed them along with the existing SOCs. © 2015 IEEE.
Open Access
Log-periodic antenna design using electromagnetic simulations
(IEEE, 2003-06) Ergül, Özgür; Gürel, Levent
It is essential to complement theoretical antenna design recipes with the numerical results obtained from electromagnetic simulations. As such, the benefit of such a hybrid procedure is demonstrated by using the design of an LP antenna as a case study. It is shown that significant performance improvements can be obtained by applying corrections shown by the simulation results.
Open Access
Mesh topology design in overlay virtual private networks
(IET, 2002) Karasan, E.; Ekin-Karasan, O.; Akar, N.; Pinar, M. C.
The mesh topology design problem in overlay virtual private networks is studied. Given a set of customer nodes and an associated traffic matrix, tunnels that connect node pairs through a service provider network are determined such that the total multi-hopped traffic is minimised. A tabu search based heuristic is proposed.
Open Access
Simulations of ground-penetrating radars over lossy and heterogeneous grounds
(IEEE, 2001) Gürel, Levent; Oğuz, U.
The versatility of the three-dimensional (3-D) finite-difference time-domain (FDTD) method to model arbitrarily inhomogeneous geometries is exploited to simulate realistic groundpenetrating radar (GPR) scenarios for the purpose of assisting the subsequent designs of high-performance GPR hardware and software. The buried targets are modeled by conducting and dielectric prisms and disks. The ground model is implemented as lossy with surface roughness, and containing numerous inhomogeneities of arbitrary permittivities, conductivities, sizes, and locations. The impact of such an inhomogeneous ground model on the GPR signal is demonstrated. A simple detection algorithm is introduced and used to process these GPR signals. In addition to the transmitting and receiving antennas, the GPR unit is modeled with conducting and absorbing shield walls, which are employed to reduce the direct coupling to the receiver. Perfectly matched layer absorbing boundary condition is used for both simulating the physical absorbers inside the FDTD computational domain and terminating the lossy and layered background medium at the borders.