Waveguide effect enhancement of local photocurrent in hybrid organic inorganic solar cells

The local efficiency of hybrid ZnO nanorods C60 ZnPc C60 MoO3 Ag solar cells, with different nanorods length has been investigated by scanning near field optical microscopy. Simultaneous spatially resolved measurements of topography and photocurrent suggest a waveguide effect enhancement of the local photocurrent. This interpretation is supported by finite element method simulations of the light propagation in the solar cel

Mapping near field plasmonic interactions of silver particles with scanning near field optical microscopy measurements

A scanning near field optical microscope SNOM is a powerful tool to investigate optical effects that are smaller than Abbe s limit. Its greatest strength is the simultaneous measurement of high resolution topography and optical near field data that can be correlated to each other. However, the resolution of an aperture SNOM is always limited by the probe. It is a technical challenge to fabricate small illumination tips with a well defined aperture and high transmission. The aperture size and the coating homogeneity will define the optical resolution and the optical image whereas the tip size and shape influence the topographic accuracy. Although the technique has been developing for many years, the correlation between theoretically expected near field data and measurement is still not convincing. To overcome this challenge, a new information depth is reached containing four optical images at the very same position. Different nanocluster samples with diverse distributions of silver particles are characterized via SNOM in illumination and collection mode. This will lead to topographical and optical images that can be used as an input for SNOM simulations with the aim of estimating optical artifacts. Including tip, particles, and substrate, our finite element method simulations are based on the realistic geometry. Correlating the high precision SNOM measurement and the detailed simulation of a full line scan will enable us to draw conclusions regarding near field enhancements caused by interacting particle

Local photocurrent mapping and cell performance behaviour on a nanometre scale for monolithically interconnected Cu In,Ga Se2 solar cells

The local efficiency of lamellar shaped Cu(In,Ga)Se2 solar cells has been investigated using scanning near‐field optical microscopy (SNOM). Topographic and photocurrent measurements have been performed simultaneously with a 100 nm tip aperture. The lamellar shaped solar cell with monolithic interconnects (P scribe) has been investigated on a nanometre scale for the first time at different regions using SNOM. It was found that, the cell region between P1 and P2 significantly contributes to the solar cells overall photocurrent generation. The photocurrent produced depends locally on the sample topography and it is concluded that it is mainly due to roughness changes of the ZnO:Al/i‐ZnO top electrode. Regions lying under large grains of ZnO produce significantly less current than regions under small granules. The observed photocurrent features were allocated primarily to the ZnO:Al/i‐ZnO top electrode. They were found to be independent of the wavelength of the light used (532 nm and 633 nm)

Memory Efficient Deployment of an Optical Flow Algorithm on GPU using OpenMP

International audienceIn this paper, we consider the recent set of OpenMP directives related to GPU deployment and seek an evaluation through the case of an optical flow algorithm. We start by investigating various agnostic transformations that attempt to improve memory efficiency. Our case study is the so-called Lucas-Kanade algorithm, which is typically composed of a series of convolution masks (approximation of the derivatives) followed by 2 × 2 linear systems for the optical flow vectors. Since, we are dealing with a stencil computation for each stage of the algorithm, the overhead of memory accesses together with the impact on parallel scalability are expected to be noticeable, especially with the complexity of the GPU memory system. We compare our OpenMP implementation with an OpenACC one from our previous work, both on a Quadro P5000

Scratchy : A Class of Adaptable Architectures with Software-Managed Communication for Edge Streaming Applications

International audienc

Congenital diaphragmatic hernia in neonate: A retrospective study about 28 observations

Objective:Our purpose was to review our experience with congenital diaphragmatic hernia emphasizing diagnosis, management, and outcome. StudyDesign: We conducted a retrospective review of all cases of babies with congenital diaphragmatic hernia diagnosed and treated in our centre from1998 to 2010. Results: There were 28 congenital diaphragmatic hernia cases, 13 girls and 15 boys with a mean weight birth of 3 kg. Three  patients (10,6% of cases) died within a few hours after admission. In the remaining cases, surgery was performed after a stabilization period of 2 days. The diaphragmatic defect was sitting in the posterolateral left in 23 cases and right in 2 cases. Its dimensions were on average 4,5 cm, tow cases of agenesis of the cupola were seen and required the placement of  gortex prosthesis. The remaining cases are treated by direct closure ofdefect. Postoperative course was marked by an early death in context of respiratory distress in six cases and later with sepsis in tow cases. The  outcome was favourable in 17 cases (60, 7%), despite the occurrence of sepsis in four cases and evisceration in two cases.Conclusions: Congenital diaphragmatic hernia remains a serious disease with high mortality and morbidity despite advances in prenatal diagnosis and neonatal  resuscitation.Key words: Congenital diaphragmatic hernia, pulmonary hypoplasia,  tracheal occlusion, paediatric surger