Optical behaviour of display performance enhancement films

Abstract

The optical properties of holographic display screen enhancement films are investigated. Experimental data show that the on-axis scattering from such films is significantly stronger than the off-axis scattering. The results are modelled using the beam propagation method in two dimensions. Good qualitative comparisons between experimental and theoretical results are obtained.     

Effect of supplementation of low-molecular-weight chitosan oligosaccharide,GO2KA1, on postprandial blood glucose levels in healthy individuals following bread consumption

Food Science and Biotechnology - The effect of chitosan oligosaccharide (GO2KA1) administration on postprandial blood glucose levels of subjects with normal blood glucose levels was evaluated...     

Computational modeling of cortical pathways involved in action execution and action observation

Brain imaging studies in macaque monkeys have recently shown that the observation and execution of specific types of grasp actions activate the same regions in the parietal, primary motor and somatosensory lobes. This extended overlapping pathway of activations provides new insights on how primates are able to learn during observation. It suggests that an observed behavior is recognized by simulating it using the circuitry developed for action execution. In the present paper we consider how learning via observation can be implemented in an artificial agent based on the above overlapping pathway of activations. We demonstrate that the circuitry developed for action execution can be activated during observation, if the agent is able to perform action association, i.e. to relate its own actions with the ones of the demonstrator. Following this intuition, a computational model of observation/execution of grasp actions is developed and used in experiments to study its properties and learning capacities. Results show that the agent is able to associate novel objects with known behaviors only by observation. Model investigation after training reveals that, during observation, not only the same regions, but also the same neural representations are activated, implying that an observed action is understood by employing the same neural codes used for its execution.     

Proposal of a control strategy for desiccant air-conditioning systems

A control strategy for the operation of desiccant air-conditioning systems is proposed in this work. The proposed strategy consists of a basic scenario, while some alternative strategy schemes are also proposed on the basis of the approach adopted for the controlling of the humidifiers or the desiccant system operation modes included. The control strategy aims at sustaining the building conditions within values suitable for human thermal comfort, thus taking care of both temperature and humidity. The assessment of the proposed control strategy scenarios is performed in terms of effectiveness and efficiency, through the use of a desiccant system model, which takes into account the effect of transient phenomena as well. Specific information for the required hardware equipment and its implementation for the controlling of the respective system components is provided, pointing out the simplicity of the proposed solutions.     

An open source forensic tool to visualize digital evidence

Visualizing digital evidence in an easy and constructive manner is a major problem because of the advanced techniques for hiding, wiping, encrypting and deleting digital data developed during the last few years. Òo tackle this problem, a system for visualizing digital data in 3-dimensional (3D) mode has been developed. XML was used as a common language to allow fine-grained management of digital data with flexibility and ease. The extensibility of the implementation makes it particularly suitable as a research and development platform in the sector of open source computer forensics tools for the future. This article examines real-life problems that benefit from using this tool in a congenial and constructive manner to validate its key underlining concept. The design decisions that have been taken in producing the system architecture, and the features it supports are elaborated upon. To determine the effectiveness of the tool, an actual case study is presented which examines the results of the tool and why it is necessary to go for an open source model as a standard. The paper concludes with performance measurements of the tool and suggests possible extensions to make the tool even smarter.     

Tool life increase of coated carbide tools by micro blasting

In today’s production engineering nearly every cutting tool is coated. Since using the technology of coating different process chains for reconditioning have been developed. The last innovation is micro blasted coatings, which is the main topic of this paper. Concerning this topic influences on tool life have been investigated. Investigations on the tool life especially of hobbing tools were made thereby and coherences between coating bond, roughness and other attributes were discovered. The investigations were made with an aluminum oxide and a zirconium oxide as blasting abrasives and a variation of the blasting parameters pressure and period. The final result is an optimization of tool wear behavior by micro blasting of the coating.     

Theoretical formulation and experimental validation of the input-output modeling approach for large solar thermal systems

In this study, a theoretical and experimental investigation of a new modeling method for solar thermal processes, based on the input-output (I/O) approach is presented.This approach is characterized primarily by the consideration of the solar thermal system, irrespective of size, as a functionally integral set, the daily yield of which is expressed as a function of the total daily radiation, the average ambient temperature and the energy level of the storage tank at the beginning of the day.The study focuses first on the theoretical foundation of the method, based on the analysis of the evolution of the main energy quantities during a daily cycle, with emphasis on the energetically most important phase of the pseudo-steady state. By integrating the instantaneous energy balances over the entire duration of this phase, analytical expressions for the coefficients of the characteristic I/O equation arise, as a function of the main characteristics of the solar system.Subsequently, the experimental validation of the proposed approach is presented, based on the comparison of theoretical results with extensive measurements on two typical large-scale solar systems, one with a fully-stratified and the other with a fully-mixed thermal storage tank, respectively.     

Transient Photoinduced Absorption in Ultrathin As-grown Nanocrystalline Silicon Films

We have studied ultrafast carrier dynamics in nanocrystalline silicon films with thickness of a few nanometers where boundary-related states and quantum confinement play an important role. Transient non-degenerated photoinduced absorption measurements have been employed to investigate the effects of grain boundaries and quantum confinement on the relaxation dynamics of photogenerated carriers. An observed long initial rise of the photoinduced absorption for the thicker films agrees well with the existence of boundary-related states acting as fast traps. With decreasing the thickness of material, the relaxation dynamics become faster since the density of boundary-related states increases. Furthermore, probing with longer wavelengths we are able to time-resolve optical paths with faster relaxations. This fact is strongly correlated with probing in different points of the first Brillouin zone of the band structure of these materials.     

Use of Fresnelets for phase-shifting digital hologram compression.

Fresnelets are wavelet-like base functions specially tailored for digital holography applications. We introduce their use in phase-shifting interferometry (PSI) digital holography for the compression of such holographic data. Two compression methods are investigated. One uses uniform quantization of the Fresnelet coefficients followed by lossless coding, and the other uses set portioning in hierarchical trees (SPIHT) coding. Quantization and lossless coding of the original data is used to compare the performance of the proposed algorithms. The comparison reveals that the Fresnelet transform of phase-shifting holograms in combination with SPIHT or uniform quantization can be used very effectively for the compression of holographic data. The performance of the new compression schemes is demonstrated on real PSI digital holographic data.