FAILURE MODE OF THE WEFTLESS BEAD AND EVALUATION OF IMPROVED CONTINUOUS SINGLE WIRE BASED BEAD

Weftless Bead design has long been in existence and still used in many passenger car, bus, truck and agriculture tractors. The ideal bead design is a high strength flexible cable with minimal cross section and covered by rubberized nylon, rayon or steel wire side wall. The basic tire bead designs are weftless bead with rubberized ribbon of parallel wires of multiple wound layers and a continuous wire wound in sufficient number of loops to give the required strength. Weftless bead failures generally occur within about 5cm from the end of the overlapping parallel wire ribbon. The cause for this failure is generally attributed to the mounting process in which the diameter of the tire bead is changed during the mounting process in the well of the rim. A finite element model of the tire bead was developed and under the known stresses of the mounting and final use conditions. The Weftless bead generally consists of five steel wires in parallel in a continuous rubber tape or ribbons, which loosely secures the wires in a soft insulating rubber. The ribbon is wound into a hoop with four courses resulting in a grommet composed of a stack of wires. This ribbon with ten cut ends forming a splice, with five at the inner cut edge and five at the outer cut edge. A continuous bead formed from a single wire does not have this failure prone splice region. Field data and the finite element calculations show the failure point of the weftless bead is almost always at the under lap or at the starting point of the weftless bead. Continuous wire bead have significant advantages in safety over the Weftless bead still used in tires

Invasive Monitoring in the Intensive Care Unit

The purpose of monitoring of the patient in an intensive care unit (ICU) is to improve patient care, like bringing about a change in the treatment or transfer of the patient to a step-down unit. Monitoring also shows the extent of compliance with a formulated standard of care or the degree of deviation from the expected standard of care. The monitoring used for a patient admitted to an ICU can be invasive or noninvasive. Invasive monitoring in an ICU includes arterial blood pressure, transesophageal Doppler, central venous pressure (CVP) measurement, pulmonary artery catheterization, arterial blood gas (ABG) analysis and measurement of intracranial pressure (ICP) and intra-abdominal pressure (IAP). Monitoring of the physiologic parameters depends on the underlying illness of the patient and the availability of equipment in the ICU

A new hybrid acquisition scheme for CDMA systems employing short concatenated codes

With the rapid growth of Personal Wireless Communications in our times and the important role being played by Code Division Multiple Access (CDMA) in the realization of the goals of second generation wireless systems, there is an ever increasing need for the development of better acquisitions techniques along with the study of a variety of techniques. Noting the important role of synchronization in CDMA systems, active research is being carried out to develop synchronization (acquisition+tracking) schemes that suit particular applications. In the first part of this thesis we propose a New Hybrid Acquisition Scheme for CDMA systems employing Short Concatenated Codes. A new coding scheme using short concatenated codes is presented along with a detailed description of a new hybrid acquisition scheme. Simulation studies of the scheme are performed in a multiple access and additive white gaussian noise environment. In the second part of the thesis, a Simplified Analytical Model of the scheme is developed using the state transition flow diagram approach and standard signal flow graph reduction techniques. Expressions for the mean and variance of the acquisition along with the probability of detection are developed. Finally the simplified model is studied in a Rayleigh fading channel

Multimode VIS–NIR transmission through silver coated hollow optical waveguides

Multimode transmission of continuous wave 633 nm radiation and 1064 nm Q-switched Nd:YAG pulses using silver coated hollow core optical waveguides (HCWs) with bore diameters of 700 μm and 1000 μm is reported. The effect of launch conditions, input beam polarization and waveguide bore diameter on the pulse energy transmission and potential for focussing the beam effectively at the HCW exit is detailed. An optimal launch f-number range of 155–165 is identified for minimizing the exit angle