Demonstration of Bidirectional Services Using MPEG‐4 BIFS in Terrestrial DMB Systems

Digital broadcasting technology has developed focusing on multi‐channel/multi‐media, high‐definition quality, and mobility‐support. Recently, there has been a clear trend toward bidirectional service with the convergence between broadcasting and communication. The broadcasting viewer is no longer simply a passive receptor but has also become an information generator. Currently, the digital multimedia broadcasting (DMB) specifications are the major standard for portable digital broadcasting and have been establishing the overall guidelines for bidirectional service using the MPEG‐4 system. While detailed specifications for DMB systems are not well‐established for bidirectional service yet, they share the basic concepts underlying the European Eureka‐147 Digital Audio Broadcasting (DAB) system. This paper develops key scenarios for bidirectional service in DMB, describes the signal transaction of broadcasting and return channels, and demonstrates typical scenarios using binary format for scenes (BIFS) in the MPEG‐4 system.     

Computerised analysis of foetal heart rate variation: prediction of adverse perinatal outcome in patients undergoing prostaglandin induction of labour at term

The aim of this study was to determine the value of antenatal numerical assessment of foetal heart rate variation in the prediction of adverse perinatal outcome in patients undergoing prostaglandin induction of labour at term. Two hundred and seven patients who underwent prostaglandin cervical ripening after 37 weeks gestation for the indications of pregnancy-induced hypertension, foetal growth retardation or post-dates pregnancy were included in this study. Prior to commencement of cervical ripening, a 30-minute cardiotocography tracing was recorded on the System 8000 machine and the long-term and short-term variations were calculated. Forty-three patients (20.8%) had a long-term variation of less than 30 ms; 9 (4.3%) had a short-term variation of less than 3 ms. The sensitivity and positive predictive values of long-term variation in the prediction of admission to neonatal special care unit were 25.6% and 23.2%, respectively. Corresponding values for short-term variation were 2.6% and 11.1%, respectively. The sensitivity and positive predictive values of long-term variation in the prediction of caesarean section for foetal distress were 33.3% and 9.3%, respectively. Corresponding values for short-term variation were 8.3% and 11.1%, respectively. Long-term and short-term variations appeared to be both poor predictors of adverse perinatal outcome. However, of 4 foetuses with both reduced antenatal heart rate variation and who were subsequently delivered by caesarean section for foetal distress in labour, all 4 were admitted to neonatal special care unit (NSCU). Foetuses with intrapartum evidence of foetal distress were more likely to be admitted to NSCU when antenatal foetal heart rate variation was reduced.     

Effective comminution of diatomaceous earth in a vertical type jet mill

Comminution characteristics of diatomaceous earth have been investigated in a vertical type jet mill of pilot plant scale; the diameter of the chamber of mill is 26.3 cm. Fluidization of the particles in the chamber has been proposed to enhance the comminution efficiency of the jet mill by promoting the effective contacting of powders with compressed air as well as the chamber wall. Effects of the pressures or densities of pulverizing-air and fluidizing-air and comminution time on the mean size of the particles and the rate of comminution have been examined. The statistical analysis of pressure fluctuations in the chamber of the mill has been utilized to predict the characteristics of the vertical-type jet mill taking advantage of the fluidization technique. The particle size and comminution rate have been correlated with the operating variables, respectively.     

Interfacial crack tip field in anisotropic/isotropic bimaterials

The co-cured joint is more efficient than the adhesively bonded joint for composite structures because of its several advantages. However, failure analysis of the co-cured joint has just a little been reported since the co-cured joining method was introduced. Observing based on the experimental results, failure starts at the interface corner of the co-cured joint. Therefore, it is important to consider stress intensities at the interface corner of the co-cured joint.

In this paper, the eigenvalue problem was used to determine asymptotic stress and displacement fields near the interface corner between composite and steel adherends. For obtaining stress intensities at the interface corner a path independent conservative line integral was used.     

RF CMOS low-phase-noise LC oscillator through memory reduction tail transistor

Based on the understanding of flicker noise generation in "silicon metal-oxide semiconductor field-effect transistors" (MOSFETs), a novel method for improving the phase noise performance of a CMOS LC oscillator is presented. Zhou et al. and Hoogee have suggested that the 1/f noise can be reduced through a switched gate, and the flicker noise generated is inversely proportional to the gate switching frequency. The novel tail transistor topology is compared to the two popular tail transistor topologies, namely, the fixed biasing tail transistor and without tail transistor. Through this technique, a figure of merit of 193 dB is achieved using a fully integrated CMOS oscillator with a tank quality factor of about 9.     

The contraction of lattice constant and the reduction of growth rate in p-InGaAs grown by organometallic vapor phase epitaxy

We have investigated the effect of diethylzinc (DEZn) on the lattice constant and the growth rate of InGaAs. Introducing DEZn for p-type doping induces the contraction of lattice constant and the reduction of growth rate compared to undoped InGaAs. Depletion of indium is responsible for these effects. These effects are reduced at lower growth temperatures or at lower growth pressures. From the observed effects of the growth temperatures and the growth pressures on the contraction of the lattice constant, it is concluded that depletion of indium occurs in the gas phase.     

An adaptation algorithm for parallel model reference adaptive bilinear systems

An adaptation algorithm is presented for parallel model reference adaptive bilinear systems. The output error converges asymptotically to zero and the parameter estimates are bounded for stable reference models. The convergence criterion depends only upon the input sequence and a priori estimates of the maximum parameter values. A passivity condition, which is generally difficult to verify, is not required.