Hybrid Solar Cells Based in Silicon Nanowires: Electronic Simulation and Optimization

Silicon - This paper presents recent progress in computational modeling on blend morphology of silicon nanowires (SiNWs) dispersed in a conjugated polymer poly(3-hexylthiophene) P3HT hybrid solar...     

Hash key-based image encryption using crossover operator and chaos

This paper proposes a color image encryption scheme using one-time keys based on crossover operator, chaos and the Secure Hash Algorithm(SHA-2). The (SHA-2) is employed to generate a 256-bit hash value from both the plain-image and the secret hash keys to make the key stream change in each encryption process. The SHA-2 value is employed to generate three initial values of the chaotic system. The permutation-diffusion process is based on the crossover operator and XOR operator, respectively. Experimental results and security analysis show that the scheme can achieve good encryption result through only one round encryption process, the key space is large enough to resist against common attacks,so the scheme is reliable to be applied in image encryption and secure communication.     

Local nonlinear unknown input observer

This paper proposes a new nonlinear unknown input observer. The observer design approach utilizes the first order Taylor expansion. The observer gains are then obtained by a systematic method. In this paper, we added some improvements to this method. The developed approach also can enable observer design for a large class of differentiable nonlinear systems. The necessary and sufficient conditions for the existence of the observer are given. A numerical example is given to illustrate the attractiveness and the simplicity of the new design procedure.     

Combining temporal partitioning and temporal placement techniques for communication cost improvement

In this paper, we present a typical temporal partitioning methodology that temporally partitions a data flow graph on reconfigurable system. Our approach optimizes the communication cost of the design. This aim can be reached by minimizing the transfer of data required between design partitions and the routing cost between FPGA modules. Consequently, our algorithm is composed by two main steps. The first step aims to find a temporal partitioning of the graph. This step gives the optimal solution in term of communication cost. Next, our approach builds the best architecture, on a partially reconfigurable FPGA, that gives the lowest routing cost between modules. The proposed methodology was tested on several examples on the Xilinx Virtex-II pro. The results show significant reduction in the communication cost compared with others famous approaches used in this field.     

Inelastic Neutron Scattering and Density Functional Theory–Molecular Dynamics Study of Si Dynamics in Ti3SiC2

Observed differences between measured and calculated elastic constants for Ti₃SiC₂ are investigated using Density Functional Theory and Inelastic Neutron Scattering. The agreement between the calculated lattice dynamics and the dynamics measured by inelastic neutron scattering is considered good except at energies below ~20 meV where discrepancies suggest anharmonic potentials. This suggestion is confirmed by Density Functional Theory—Molecular Dynamics simulation which shows multiple site occupancy of the Si atoms within the basal plane at finite temperature and produces a calculated inelastic spectrum in better agreement with the measured spectrum in the low‐energy region. The highly anharmonic potential energy surface of the Si atoms offers an explanation for the failure of elastic constants, calculated based on the harmonic approximation, to agree with initial experimental measurements.     

Design and implementation of new,silicon-based,cross-coupling reactions: importance of silicon-oxygen bonds

This Account chronicles the conceptual development, proof of principle, exploration of scope, and mechanistic investigations of a newly developed class of palladium-catalyzed cross-coupling reactions of silicon derivatives. Under the influence of fluoride activation a myriad of oxygen-containing silicon moieties undergo mild and stereospecific cross-coupling. The diversity of methods for introduction of silicon groupings into organic molecules and the range of organic electrophiles that can be used are outlined.     

L'effet du niveau d'experiencing du client et de l'aidant sur l'abandon d'un processus thérapeutique.

Studied the effect of client and therapist level of experiencing, beginning with the initial stage of psychological counseling, on early termination of therapy. Human subjects: 32 male and female Canadian adults (mean age 30–32 yrs) (personality disorders, neuroses, or interpersonal problems) (clients of therapists). 19 normal male and female Canadian adults (mean age 31 yrs) (graduate students) (therapists). Clients were subdivided into 2 groups: those who had terminated therapy (early or late), and those who had not terminated therapy. Ss were interviewed. Levels of experiencing were compared for the 2 groups of clients and for therapists who had counseled these clients. Tests used: The Global Assessment Scale, Psychiatric Symptom Index (F. Ilfeld, 1976), and Experiencing Scale (P. Mathieu-Coughlan and M. Klein, 1984). (PsycINFO Database Record (c) 2010 APA, all rights reserved)