Dumitru Cazacu

Notice of Violation of IEEE Publication Principles Time minimization of hybrid BIST for systems-on-chip

In this paper, we concentrate on hybrid BIST optimization for multi-core designs. As total cost minimization for multi-core systems is an extremely complex problem and is rarely used in reality, the main emphasis here is on test time minimization under memory constraints with different test architectures. The memory constraints can be seen as limitations of on-chip memory or ATE memory, where the deterministic test set will be stored, and therefore with high practical importance. We will concentrate on one large classes of test architectures and we assume that every core is equipped with its own pseudorandom pattern generator and only deterministic patterns have to be transported to the cores. For this architecture we will describe test-per-clock as well as test-per-scan application schemes.

Notice of Violation of IEEE Publication Principles Cost minimization for ASIC hybrid BIST designs

In this paper are presented different methods for a hybrid BIST cost optimization for single-core designs. For selecting the optimal switching moment from the pseudorandom test mode to the stored test mode, two algorithms were proposed for calculating the complete cost curve of the different hybrid BIST solutions. The first one is a straightforward method based on using traditional fault simulation and test pattern generation. The second one is based on fault table manipulations and uses test compaction. The experimental simulated results demonstrate the feasibility of the approach and the efficiency of the fault table based cost calculation method.

Analysis of COMSOL multiphysics parallel performance on a multi-core system

In this paper the influence of the multi-core architecture on the processing time for solving a 2D problem, described by a non homogenous Poisson PDE, in COMSOL, was considered. Only the direct solvers were taken into account. Different levels of mesh refinement were compared and different Lagrange finite element orders have been used.

Performance improvement of the Comsol FEM analysis of 3D magnetostatic field problems on mobile computers

Being mobile is an important aspect in research, education and other domains. The hardware available for mobile devices has reduced computing power therefore it is important to determine its usability in the context of complex problem analysis. This paper presents the usage of direct and iterative solvers for a 3D magnetostatic finite element problem and analyses the results in relation to the hardware setup. The paper presents conclusions regarding the optimization of the simulation in order to obtain relevant results for the test problem with the reduced computing power of a mobile platform.

System using a hybrid application for virtual reality 3D drawing

Smart devices have many sensors that capture the user data and use it for device control, improving the user experience, or send it through a computer network in order to be processed. The interaction between user and applications, especially in virtual reality, is made via motion and gestures with information offered by sensors such as accelerometer, compass or gyroscope. In order to reduce the complexity of developing this type of applications, it is possible to write hybrid applications that allow the programmer to code using web technologies then deploy and run the resulted applications natively on multiple operating systems. This paper presents the implementation of a virtual reality drawing hybrid application, created with the Telerik Mobile platform, which reads the compass and accelerometer data and sends the information to a server that creates a 3D representation using the Processing Development Environment.

On the multishell cylindrical magnetostatic shields: Analytical and numerical approach

In this paper one and two shells magneto static cylindrical shields are considered. Using the interface conditions at the discontinuity surfaces between the media, algebraic systems of equations have been obtained. Solution of the systems offers the value of the magneto static field inside the shields. Structures of the systems matrices were analyzed and their sparsity patterns was visualized. 3D Finite element simulations of shields with different lengths were performed and comparisons with analytical results were done. Good agreement, among the shields efficiencies for different lengths and the analytical value, were obtained.

On the computation of the SAR for a 3D human head model using Ansys HFSS

The exposure to RF electromagnetic radiation of the cell phones has generated certain concerns about the possible health hazards. In this paper the peak SAR values for two 3D head models, with two and three layers, were computed, using ANSYS/HFSS finite element software. The values were obtained for three frequencies, both for UE and USA standards. Also three angles of rotation of the cell phone were considered. A multicore implementation was performed and the simulation times for each model were compared.

Finite element numerical experiments on the absorption of the EMF radiation in 3D human head models

Intesive usage of cellular phones has increased the public concern about their possible health hazards. Experimental as well as numerical approaches has been used in order to evaluate the biological effects. Most of the papers used the finite diference time domain(FDTD) and the MoM (method of moments) numerical methods .This paper deals with the computation of the local peak SAR and absorbed power values using the finite element method .Three spherical models have been taken into account: homogenous and layered. They were exposed to a dipole antenna operating at different frequenciesand different distances .The results were compared with those from the literature and a good agreement was obtained.

The Evaluation of the PCB's Behaviour under the Mechanical Stress

The aspect of the vulnerability of electronics generated by the mechanical causes requires a special analyzing and testing effort of the packages in the context of each different particular application. The main goal of this paper is to present the numerical evaluation by finite element analysis of the common class of PCBs under the mechanical stress. This work contributes to the study of packaged electronics vulnerability by comparing the numerical results with experimental tests.