Digital social signal processing - theorectical underpinning and research agenda

Organizations make increasingly use of social media in order to compete for customer awareness and improve the quality of their goods and services. Multiple techniques of social media analysis are already in use. Nevertheless, theoretical underpinnings and a sound research agenda are still unavailable in this field at the present time. In order to contribute to setting up such an agenda, we introduce digital social signal processing (DSSP) as a new research stream in IS that requires multi-facetted investigations. Our DSSP concept is founded upon a set of four sequential activities: sensing digital social signals that are emitted by individuals on social media; decoding online data of social media in order to reconstruct digital social signals; matching the signals with consumers’ life events; and configuring individualized goods and service offerings tailored to the individual needs of customers. We further contribute to tying loose ends of different research areas together, in order to frame DSSP as a field for further investigation. We conclude with developing a research agenda.

SBS-based slow light in optical fibers: optimum design considerations for undistorted slow-light signal propagation in steady-state and transient regimes

SPIE

Digital light

Artists Description: Moving rooms and domestic objects pass through the interior of the translucent house as we peer into it. At night they softly emanate a glow much like the glow of a television in the living room. The animated space is choreographed and timed in its movement, broadcasting the contents of the house. There is an interplay between real object and virtual object: the house is made of transparent/translucent glass while the interior objects are virtual images on the screen; total internal reflection occurs so that the image can be seen from certain angles only; the glass is a medium which distorts the animated image, while the animated image permeates the glass with its colour, movement and glow.

Digital Light Microscopy of Macroporous Ceramics Processed by Consolidation Casting with Mixtures of Native Starches

Porosity in starch consolidation casting technique is rightly related to original size and morphology of starch granules, leaving a pore structure after burning out. This work reports the results for the addition of different native potato and corn starch proportions in suspension,; with TiO(2) (rutile) powder. Gelling temperature have been defined after observation under light microscopy using a heating stage. Analysis of porous network and isolated pores have been clone from images of samples surfaces obtained by depth from focus reconstruction, revealing a qualitative correlation of pores characteristics and starches additions in suspensions, suggesting that the presence of isolated or interconnected pores can be handled by starches selection to control the amylopectin and amylose contents in slurries. Also, the analysis of porous fraction distribution shows no consistent pattern through specimens' volume according to starches in mixtures.

Digital light beam deflector with liquid crystals

In this communication we report a new method for deflecting a laser beam with liquid crystals cells. In order to improve previous response times of these cells, we use a wedge structure with twisted orientation.

Digital light beam deflector with liquid cristal (1980)

In this letter , we report a new method for óptical switching based on the electro-optical properties of liquid crystal materials and, in particular, of the nematic type. The basis of this new method is the use of twisted wedge structure that has not been reported before elsewhere. In the past several years , great efforts in integrated optics have been made to develop optical switching devices with fast speed by using electro-optic, acousto-optic or magneto -optic materials. A mechanically operated óptical switch made of grade-index rod 1enses and e1ectromagnets has been proposed too . Switches of this kind include one input and two output waveguides and, depending on the app1ied voltage, one incident light on the switch exits either in one or another of the two output waveguides.

Organizational, DS, GS, and depot maintenance manual including repair parts : light, signal, surveying, 5 in. dia. reflector, grille housing, in carrying case (military design) FSN 6675-641-3537.

"June 1965."

Five channel WDM communication using a single a:SiC-H double pin photo device

Amorphous SiC heterostructures built as a double pin device has a non linear spectral gain which is a function of the signal wavelength that impinges on its front or back surface. Illuminating the device with several single wavelength data channels in the visible spectrum allows for Wavelength Division Multiplexing (WDM) digital communication. Using fixed ultra-violet illumination at the front or back surfaces enables the recovery of the multiplexed channels. Five channels, each using a single wavelength which is modulated by a Manchester coded signal at 12,000 bps, form a frame with 1024 bits with a preamble for signal intensity and synchronisation purposes. Results show that the clustering of the received signal enables the successful recovery of the five channel data using the front and back illumination of the surfaces of the double pin photo device. (C) 2015 Elsevier B.V. All rights reserved.

Resolution and noise in ghost imaging with classical thermal light

The resolution and classical noise in ghost imaging with a classical thermal light are investigated theoretically. For ghost imaging with a Gaussian Schell model source, the dependences of the resolution and noise on the spatial coherence of the source and the aperture in the imaging system are discussed and demonstrated by using numerical simulations. The results show that an incoherent source and a large aperture will lead to a good image quality and small noise.

Reconfigurable photonic logic architecture

The amorphous silicon photo-sensor studied in this thesis, is a double pin structure (p(a-SiC:H)-i’(a-SiC:H)-n(a-SiC:H)-p(a-SiC:H)-i(a-Si:H)-n(a-Si:H)) sandwiched between two transparent contacts deposited over transparent glass thus with the possibility of illumination on both sides, responding to wave-lengths from the ultra-violet, visible to the near infrared range. The frontal il-lumination surface, glass side, is used for light signal inputs. Both surfaces are used for optical bias, which changes the dynamic characteristics of the photo-sensor resulting in different outputs for the same input. Experimental studies were made with the photo-sensor to evaluate its applicability in multiplexing and demultiplexing several data communication channels. The digital light sig-nal was defined to implement simple logical operations like the NOT, AND, OR, and complex like the XOR, MAJ, full-adder and memory effect. A pro-grammable pattern emission system was built and also those for the validation and recovery of the obtained signals. This photo-sensor has applications in op-tical communications with several wavelengths, as a wavelength detector and to execute directly logical operations over digital light input signals.

Digital Illumination for Augmented Studios

Virtual studio technology plays an important role for modern television productions. Blue-screen matting is a common technique for integrating real actors or moderators into computer generated sceneries. Augmented reality offers the possibility to mix real and virtual in a more general context. This article proposes a new technological approach for combining real studio content with computergenerated information. Digital light projection allows a controlled spatial, temporal, chrominance and luminance modulation of illumination – opening new possibilities for TV studios.

Digital chaos analysis in optical logic structures

Digital chaotic behavior in an optically processing element is analyzed. It was obtained as the result of processing two fixed trains of bits. The process is performed with an optically programmable logic gate. Possible outputs, for some specific conditions of the circuit, are given. Digital chaotic behavior is obtained, by using a feedback configuration. Different ways to analyze a digital chaotic signal are presented.

Analysis of digital chaotic optical signals

The main objective of this paper is to present some tools to analyze a digital chaotic signal. We have proposed some of them previously, as a new type of phase diagrams with binary signals converted to hexadecimal. Moreover, the main emphasis will be given in this paper to an analysis of the chaotic signal based on the Lempel and Ziv method. This technique has been employed partly by us to a very short stream of data. In this paper we will extend this method to long trains of data (larger than 2000 bit units). The main characteristics of the chaotic signal are obtained with this method being possible to present numerical values to indicate the properties of the chaos.

Vitamin B2-based blue-light photoreceptors in the retinohypothalamic tract as the photoactive pigments for setting the circadian clock in mammals

In mammals the retina contains photoactive molecules responsible for both vision and circadian photoresponse systems. Opsins, which are located in rods and cones, are the pigments for vision but it is not known whether they play a role in circadian regulation. A subset of retinal ganglion cells with direct projections to the suprachiasmatic nucleus (SCN) are at the origin of the retinohypothalamic tract that transmits the light signal to the master circadian clock in the SCN. However, the ganglion cells are not known to contain rhodopsin or other opsins that may function as photoreceptors. We have found that the two blue-light photoreceptors, cryptochromes 1 and 2 (CRY1 and CRY2), recently discovered in mammals are specifically expressed in the ganglion cell and inner nuclear layers of the mouse retina. In addition, CRY1 is expressed at high level in the SCN and oscillates in this tissue in a circadian manner. These data, in conjunction with the established role of CRY2 in photoperiodism in plants, lead us to propose that mammals have a vitamin A-based photopigment (opsin) for vision and a vitamin B2-based pigment (cryptochrome) for entrainment of the circadian clock.

Blue Light and Abscisic Acid Independently Induce Heterophyllous Switch in Marsilea quadrifolia1

In natural habitats Marsilea quadrifolia L. produces different types of leaves above and below the water level. In aseptic cultures growth conditions can be manipulated so that leaves of the submerged type are produced continuously. Under such conditions the application of either blue light or an optimal concentration of abscisic acid (ABA) induced the development of aerial-type leaves. When fluridone, an inhibitor of ABA biosynthesis, was added to the culture medium it did not prevent blue light induction of aerial leaf development. During blue light treatment the endogenous ABA level in M. quadrifolia leaves remained unchanged. However, after the plants were transferred to an enriched medium, the ABA level gradually increased, corresponding to a transition in development from the submerged type of leaves to aerial leaves. These results indicate that the blue light signal is not mediated by ABA. Therefore, in the regulation of heterophyllous determination, discrete pathways exist in response to environmental signals.