Cross spectral iris recognition for surveillance based applications

Multimedia Tools and Applications - Human iris has been explored as one of the most promising biometric traits since last many years. This paper presents a new ingenious feature extraction approach...     

Postoperative analgesia. Simple methods for improvements exist

An improved, combined staining method for myofibrillar ATPase (m-ATPase) and for acetylcholinesterase activity is described. This method allows the observations, on the same slide, of the classical histochemical m-ATPase profile following the Brooke and Kaiser technique and the neuromuscular junction morphology. Thus the pattern of innervation, nerve ending structure and number of nerve endings along the fibres is shown simultaneously for the basic differentiation between slow and fast fibres. The use of acidic and alkaline preincubation allows better visualization of endplate morphology and avoids the masking effect of a positive m-ATPase reaction. The technique has been validated on skeletal muscles from avian and mammalian species.     

An efficient new method for the detection of QRS in electrocardiogram

A simple and efficient new method for QRS detection in Electrocardiogram (ECG) is proposed in this paper. Initially data is preprocessed using two stage median filter for removing baseline drift. The second stage enhances the peaks of ECG wave components by using sixth power of signal. The next stage identifies the QRS complex by taking a variable window size. The detection sensitivity (Se) and positive predictivity (+P) of CSE (Common Standards for Quantitative Electrocardiography) measurement database, MIT/BIH (Massachusetts Institute of Technology/Beth Israel Hospital) Arrhythmia database, European ST-T database and QT database are Se 99.51 & +P 99.69%, Se 99.21 & +P 99.34%, Se 99.53 & +P 99.72% and Se 99.87 & +P 99.95% respectively. These four standard databases used to perform QRS detection considered 368 cases, tested 1,006,168 beats and achieved overall average sensitivity 99.52% and positive predictivity 99.69%. The MIT/BIH Noise Stress Test Database also tested by proposed method.     

Dielectric Properties of the "Twinned" 8H-Hexagonal Perovskite Ba8Nb4Ti3O24

The dielectric properties of dense ceramics of the "twinned" 8H-hexagonal perovskite Ba₈Nb₄Ti₃O₂₄ are reported. Single-phase powders were obtained from the mixed-oxide route at 1325°C and ceramics (>92% of the theoretical X-ray density) by sintering in air or flowing O₂ at 1400°–1450°C. The ceramics are dc insulators with a band gap >3.4 eV that resonate at microwave frequencies with relative permittivity, ɛ_r∼44–48, quality factor, Q × f _r∼21 000–23 500 GHz (at f _r∼5.5 GHz) and temperature coefficient of resonant frequency, TC _f,∼+115 ppm/K.     

A single-solenoid pulsed-magnet system for single-crystal scattering studies

We present a pulsed-magnet system that enables x-ray single-crystal diffraction in addition to powder and spectroscopic studies with the magnetic field applied on or close to the scattering plane. The apparatus consists of a single large-bore solenoid, cooled by liquid nitrogen. A second independent closed-cycle cryostat is used for cooling samples near liquid helium temperatures. Pulsed magnetic fields close to ~30 T with a zero-to-peak-field rise time of ~2.9 ms are generated by discharging a 40 kJ capacitor bank into the magnet coil. The unique characteristic of this instrument is the preservation of maximum scattering angle (~23.6°) on the entrance and exit sides of the magnet bore by virtue of a novel double-funnel insert. This instrument will facilitate x-ray diffraction and spectroscopic studies that are impractical, if not impossible, to perform using split-pair and narrow-opening solenoid magnets. Furthermore, it offers a practical solution for preserving optical access in future higher-field pulsed magnets.     

Large-area organic photovoltaic module—Fabrication and performance

Here we describe the fabrication of the largest (233 cm² total area) organic photovoltaic (OPV) module (polymer:fullerene) to be certified by the National Renewable Energy Laboratory (NREL). OPV solar cells were fabricated at Plextronics by spin coating a blend of poly 3-hexylthiophene-2,5 diyl (P3HT) and [6,6] phenyl C₆₁ butyric acid methyl ester (PCBM) on top of our hole transport layer (HTL), Plexcore^® OC. In laboratory-scale devices (0.09 cm²), this system routinely exhibits power conversion efficiencies exceeding 3.7%. This P3HT:PCBM active layer and HTL ink system was used to scale up to the larger area module (15.2 cm×15.2 cm module size, i.e. 233 cm² total area; 108 cm² active area), which was certified by NREL as having 1.1% total area efficiency (3.4% active area efficiency).     

Biaxial tensile behavior of spunbonded nonwoven geotextiles

Geotextiles can be successfully employed for any geotechnical application when they are able to sustain pre-defined levels of tensile stresses. The biaxial tensile test has an advantage over other tensile test methods in that it does not allow “necking” during deformation which simulates the operational conditions of geotextiles under confined stresses. In this study, the model for uniaxial tensile behavior of nonwovens has been modified to investigate the biaxial tensile behavior of spunbonded geotextiles. The model has included the effect of fiber re-orientation, stress-strain behavior of constituent fibers, and physical characteristics of nonwovens when the geotextile specimen is laterally constrained. A comparison is made between predicted and experimental stress-strain curves obtained from previous work (Bais-Singh and Goswami, 1998). Theoretical findings of biaxial tensile behavior obtained using the layer theory are also critically discussed. In addition, it has been revealed that fiber re-orientation is a key factor in translating the random spunbonded nonwoven geotextiles to anisotropic structures under defined biaxial tensile stresses.     

Optical Kerr switching technique for the production of a picosecond,multiwavelength CO2 laser pulse

A wavelength-independent method for optical gating, based on the optical Kerr effect, has been demonstrated. Using this method, we produced 100-ps, 10-kW, two-wavelength pulses (10.3 and 10.6 microm) with a signal-to-background ratio contrast of 10(5) by slicing a long CO2 pulse. The capability of gating consecutive pulses separated on a picosecond time scale with this method is also shown.     

Medium-access control protocols for WDM-based optical access networks with passive-star clusters interconnected by a backbone ring

This paper investigates the performance of medium access control (MAC) protocols in a wavelength-division multiplexing (WDM) based optical access network consisting of a backbone ring interconnecting several passive-star-based clusters of optical networking units (ONUs) at customer premises. Each cluster is connected to the backbone through an access node (AN). A scheduler located in each AN, executes two MAC protocols, one for the intracluster traffic and the other for the intercluster traffic. In order to maintain the quality of service, the scheduler in the AN employs, priority-based queuing for the intercluster traffic on pre-assigned wavelengths. For controlling the intracluster traffic, the scheduler employs pre-transmission coordination with ranging and look-ahead functionalities in the MAC protocol. The performance of MAC protocol for intracluster traffic is evaluated through event-driven simulation, while for intercluster traffic the MAC performance is evaluated through analytical modeling of the queuing system employing two dynamic bandwidth management schemes. Performance of the intracluster MAC protocol is shown to be improved by novel use of subcarrier multiplexing on the wavelength used for the control packet transmission. A comparative study of the two intercluster schemes in terms of end-to-end delay is carried out, to understand the effect of priority queuing on the real-time and non-real-time service packets.     

Study of inductively coupled Cl2/BCl3 plasma process for high etch rate selective etching of via-holes in GaAs

We have investigated the selective etching of 50 μm diameter via-holes for etch depth >200 μm using 30 μm thick photo resist mask in Inductively Coupled Plasma system with Cl₂/BCl₃ chemistry. Resultant etch rate/etch profiles are studied as a function of ICP process parameters and photo resist mask sidewall profile. Etch yield and aspect ratio variation with process pressure and substrate bias is also investigated at constant ICP power. The etch yield of ICP process increased with pressure due to reactant limited etch mechanism and reached a maximum of ∼19 for 200 μm depth at 50 mTorr pressure, 950 W coil power, 80 W substrate bias with an etch rate ∼4.9 μm/min. Final aspect ratio of etched holes is increased with pressure from 1.02 at 20 mTorr to 1.38 at 40 mTorr respectively for fixed etch time and then decreased to 1.24 at 50 mTorr pressure. The resultant final etch profile and undercut is found to have a strong dependence on the initial slope of photo resist mask sidewall angle and its selectivity in the pressure range of 20-50mTorr.