Mirror or Molder? A Study of Media Coverage,Stock Prices,and Trading Volumes in Germany

This article investigates the short‐term relationship between media coverage, stock prices, and trading volumes of eight listed German companies. A content analysis of news reports about the selected companies and a secondary analysis of the daily changes in closing prices and the trading volumes of these companies were combined in a time‐series design. After ARIMA‐modeling each of them, the results suggest that media coverage rather reflects than shapes the development at stock exchanges from a short‐term perspective (2 months). There were almost no hints for a widespread media effect, that is, an impact on so many investors that it will result in a measurable change in stock prices or trading volumes. Finally, theoretical and methodological consequences for exploring widespread media effects are discussed.     

Tiny and Blurred Face Alignment for Long Distance Face Recognition

Applying face alignment after face detection exerts a heavy influence on face recognition. Many researchers have recently investigated face alignment using databases collected from images taken at close distances and with low magnification. However, in the cases of home‐service robots, captured images generally are of low resolution and low quality. Therefore, previous face alignment research, such as eye detection, is not appropriate for robot environments. The main purpose of this paper is to provide a new and effective approach in the alignment of small and blurred faces. We propose a face alignment method using the confidence value of Real‐AdaBoost with a modified census transform feature. We also evaluate the face recognition system to compare the proposed face alignment module with those of other systems. Experimental results show that the proposed method has a high recognition rate, higher than face alignment methods using a manually‐marked eye position.     

Dual mode wideband band-pass filter with notched band for communication system

This paper presents a planar microstrip wideband dual mode Band-Pass Filter (BPF) from 2 GHz to 3.4 GHz with a notched band at 2.62 GHz. The dual mode band-pass filter consists of a ring resonator with two quarter-wavelength open-circuited stubs at ?? =90° and ?? =0°, respectively. A square perturbation stub has been put at the corner of the ring resonator to increase the narrow stopbands and improve the performance of selectivity. By using a parallel-coupled feed line, a narrow notched band is introduced at the required frequency and its Fractional BandWidth (FBW) is about 5%. The proposed filter has a narrow notched band and a wide pass-band with a sharp cutoff frequency characteristic, the attenuation rate for the sharp cutoff frequency responses is 297.17 dB/GHz (calculated from 1.959 GHz with ?34.43 dB to 2.065 GHz with ?2.93 dB) and 228.10 dB/GHz (calculated from 3.395 GHz with ?2.873 dB to 3.507 GHz with ?28.42 dB). This filter has the advantages of good insertion loss in both operating bands and two rejections of greater than 16 dB in the range of 1.59 GHz to 1.99 GHz and 3.49 GHz to 3.98 GHz. Having been presented in this article, the measurement results agree well with the simulation results, which validates our idea.     

AN IMPROVED EPON UPSTREAM TRANSMISSION SCHEME WITH ZERO INTER-PERIOD IDLE LOSS

Existing Ethernet Passive Optical Network (EPON) Dynamic Bandwidth Allocation (DBA) algorithms suffer from the disadvantage of idle time loss,which lower the upstream bandwidth utilization.This letter ...     

Role of hydrogen in the surface passivation of crystalline silicon by sputtered aluminum oxide

Aluminum oxide films can provide excellent surface passivation on both p‐type and n‐type surfaces of silicon wafers and solar cells. Even though radio frequency magnetron sputtering is capable of depositing aluminum oxide with concentrations of negative charges comparable to some of the other deposition methods, the surface passivation has not been as good. In this paper, we compare the composition and bonding of aluminum oxide deposited by thermal atomic layer deposition and sputtering, and find that the interfacial silicon oxide layer and hydrogen concentration can explain the differences in the surface passivation. Copyright © 2010 John Wiley & Sons, Ltd.     

Uncertainty of the spectral mismatch correction factor in STC measurements on photovoltaic devices

Valuation of photovoltaic devices depends strongly on the measured power output of the device. This quantity is usually determined under artificial sunlight in production line measurement systems or industrial or research test labs. A practical calibration chain is realized essentially with measurements at solar simulators. The measurement conditions are defined in the IEC 60904 series of standards. An important part of the standard testing conditions is the definition of a specific spectral distribution of the sunlight (AM1.5 global). The inevitable deviations of the spectrum of artificial light sources from the standard spectrum have to be taken into account by a spectral mismatch factor. The uncertainty of this crucial correction is spectrally dependent, in most cases unknown and complex and inconvenient to evaluate. In this article a randomizing method is proposed which allows one to calculate the uncertainty of the mismatch factor from the uncertainties of the input parameters determined with high spectral resolution. Based on a range of different spectral responses of solar cells on the one hand and variations of the solar simulator spectral distribution on the other, we are able to generalize the results to a broad set of measurement configurations. A sensitivity analysis reveals the crucial wavelength regions and thus allows the systematic optimization of simulator spectra and selection of reference cells. Copyright © 2010 John Wiley & Sons, Ltd.     

Long‐Range,Entangled Carbon Nanotube Networks in Polycarbonate

A method is presented for dispersing ropes or bundles of single‐walled carbon nanotubes (RCNTs) in a polycarbonate (PC) matrix. Films of PC/RCNT composites are produced, with thicknesses ranging from 10 to 60 μm, and containing small concentrations (0.06–0.25 wt.‐%) of RCNT. Our process is based on a unique method of hot casting, annealing, and drying from dichlorobenzene solution. A wet annealing prior to complete drying yields a uniform and transparent film. Despite the low RCNT loading, scanning electron microscopy (SEM) analysis of the films after fracture reveals that the RCNTs form an entangled network throughout the film, which is a key requirement for enhanced properties. An increase of up to 30 % in the Young's modulus, as compared to PC, results with this method of composite fabrication.     

Positively Thermo‐Sensitive Monodisperse Core–Shell Microspheres

In this paper, we report on a novel family of monodisperse thermo‐sensitive core–shell hydrogel microspheres that is featured with high monodispersity and positively thermo‐responsive volume phase transition characteristics with tunable swelling kinetics, i.e., the particle swelling is induced by an increase rather than a decrease in temperature. The microspheres were fabricated in a three‐step process. In the first step, monodisperse poly(acrylamide‐co‐styrene) seeds were prepared by emulsifier‐free emulsion polymerization. In the second step, poly(acrylamide) or poly[acrylamide‐co‐(butyl methacrylate)] shells were fabricated on the microsphere seeds by free radical polymerization. In the third step, the core–shell microspheres with poly‐ (acrylamide)/poly(acrylic acid) based interpenetrating polymer network (IPN) shells were finished by a method of sequential IPN synthesis. The proposed monodisperse core–shell microspheres provide a new mode of the phase transition behavior for thermo‐sensitive “smart” or “intelligent” monodisperse micro‐actuators that is highly attractive for targeting drug delivery systems, chemical separations, sensors, and so on.     

Near‐Infrared Light‐Emitting Diodes (LEDs) Based on Poly(phenylene)/Yb‐tris(β‐Diketonate) Complexes

Near‐infrared‐emitting electroluminescent (EL) devices using blue‐light‐emitting polymers blended with the Yb complexes Yb(DBM)₃phen (DBM = dibenzoylmethane), Yb(DNM)₃phen (DNM = dinaphthoylmethane), and Yb(TPP)L(OEt) (L(OEt) = [(C₅H₅)Co{P(O)Et₂}₃]^–) have been studied. EL devices composed of Yb(DNM)₃phen blended with PPP‐OR11 showed enhanced near‐IR output at 977 nm when compared to those fabricated with Yb(DBM)₃phen/PPP‐OR11 blends. The maximum near‐IR external efficiencies of the devices with Yb(DBM)₃phen and Yb(DNM)₃phen are, respectively, 7 × 10^–5 (at 6 V and at 0.81 mA mm^–2) and 4 × 10^–4 (at 7 V, and 0.74 mA mm^–2). The optimal blend composition for EL device performance consisted of PPP‐OR11 blended with 10–20 mol‐% Yb(DNM)₃phen. A device fabricated using Yb‐(TPP)L(OEt)/PPP‐OR11 showed significantly enhanced near‐IR output efficiency, and future efforts will focus on devices fabricated using porphyrin‐based materials.     

Performance Analysis of a Discrete‐Time Two‐Phase Queueing System

This paper introduces the modeling and analysis of a discrete‐time, two‐phase queueing system for both exhaustive batch service and gated batch service. Packets arrive at the system according to a Bernoulli process and receive batch service in the first phase and individual services in the second phase. We derive the probability generating function (PGF) of the system size and show that it is decomposed into two PGFs, one of which is the PGF of the system size in the standard discrete‐time Geo/G/1 queue without vacations. We also present the PGF of the sojourn time. Based on these PGFs, we present useful performance measures, such as the mean number of packets in the system and the mean sojourn time of a packet.