Estimation of number-area-frequency dimensions of surface water bodies

This paper proposes a technique that includes a set of mathematical morphological transformations to estimate the frequency dimension. The dimension computed through a power law relationship is tallied with the dimension computed through a correlational plot. This technique is demonstrated on a two-dimensional section embodying a large number of surface water bodies, extracted from remotely sensed data, situated randomly, and the frequency dimension (D) for surface water bodies yields straight-line dependence of lnC(r) (correlational integral) on ln(r) (radius of structuring template). The correlational integral is computed for two aspects by considering the number of water bodies and their corresponding occupied areas. The number-frequency dimension and the area frequency dimension computed through correlational plots yield straight-line dependencies with slopes that are greater than unity but less than 2.0 (1.3 and 1.7, respectively).     

Two-Color Capillary Electrophoresis with On-Column Excitation and Wave-Guide Based Fluorescent Detection

An optical wave-guide based two-color capillary electrophoresis laser induced fluorescence (CE-LIF) instrument is described. The wave-guide based approach allows for on column excitation and detection with two-color discrimination. The instrument is designed to allow either electrokinetic or hydrodynamic injections. In its present configuration, the attainable limit of detection (LOD, S/N = 3) was 50 X 10⁻²¹ moles of fluorescein with a 488-nm excitation source. This study was designed to test the instrument design for applications in protein analyses. Fluorescent dyes with two different wavelengths were simultaneously separated and detected as were complexes formed by labeled antibodies to NFκB p65 and cdc2p34. Quantification of both proteins in THP-1 cell lysates performed using this approach illustrates a rapid screening application of this instrument.     

Fault tolerance in multiprocessor systems

Multiprocessor systems which afford a high degree of parallelism are used in a variety of applications. The extremely stringent reliability requirement has made the provision of fault-tolerance an important aspect in the design of such systems. This paper presents a review of the various approaches towards tolerating hardware faults in multiprocessor systems. It emphasizes the basic concepts of fault tolerant design and the various problems to be taken care of by the designer. An indepth survey of the various models, techniques and methods for fault diagnosis is given. Further, we consider the strategies for fault-tolerance in specialized multiprocessor architectures which have the ability of dynamic reconfiguration and are suited tovlsi implementation. An analysis of the state-of-the-art is given which points out the major aspects of fault-tolerance in such architectures.     

DSP-based digital FM demodulation for GMSK signals

Demodulation of Gaussian Minimum Shift Keying (GMSK) using a limiter-discriminator is a low complexity alternative to coherent demodulation. This so-called digital FM demodulation is followed by clock recovery, sampling, and thresholding. Conventionally, clock recovery is done in hardware, and matched filtering is usually not possible when the Gaussian pulse is wider than a bit duration. We propose a clock recovery technique based on discrete-time processing of the demodulated baseband signal. This technique couples very nicely with a new maximum likelihood sequence estimator for the data that uses a whitening filter followed by a Viterbi decoder. The entire detection algorithm can be implemented in an efficient manner on a Digital Signal Processor (DSP). Computer simulation results are presented to show that the new algorithm performs better than the conventional slicer by as much as 5.5 dB.     

Basic studies leading to the development of an ultrahigh strength,high fracture toughness low-alloy steel

Ultrahigh strength steels have been used increasingly in recent years for critical aircraft and aerospace structural applications. In such applications, though materials performance is of prime consideration, cost and availability makes the low-alloy steels an attractive option. This paper describes the development of an ultrahigh strength NiSiCrCoMo low-alloy steel, supported by significant findings obtained from the basic studies that were aimed at understanding how solute additions influence fracture resistance of iron, with and without the presence of carbon. The results of the basic studies, in combination with the work of Garrison (1986) on a NiSiCr steel, have profitably been employed in the development of a NiSiCrCoMo low-alloy steel possessing a strength-toughness combination quite comparable to the highly alloyed 250-grade maraging steel. Reproducibility of attractive strength and toughness properties has been established in tonnage scale melts. This steel, in the softened condition, has good formability and machinability. Weld parameters have also been established. The NiSiCrCoMo low-alloy steel thus meets the requirements of performance and cost rendering it an attractive option for advanced structural applications.     

Kinetics of emitted mass—A study with three dry powder inhaler devices

The purpose of this study was to understand the kinetics of emptying of micronised salbutamol sulphate (SS) and lactohale 300 (LH300) under varying air flow rates (30–180 L min⁻¹) from three dry powder inhaler devices, Rotahaler^® (RH), Monodose Inhaler^® (MI) and Handihaler^® (HH). Aerosol concentration vs. time profiles, determined through real-time laser diffraction particle sizing, demonstrated that the majority of the powder from RH was emitted within one second while a more prolonged aerosolisation was observed from MI and HH. Peak aerosol concentrations were achieved more rapidly from RH compared to MI for both SS and LH300. Calculated cumulative emitted mass (CCEM) vs. time profiles were obtained from the aerosol concentration vs. time profiles and the emitted mass and the rate of CCEM (k_CCEM), estimated from a modelling approach, increased with increasing air flow rates. The k_CCEMvs. air flow rate profiles of SS and LH300 were significantly different at high air flow rates. The k_CCEM was highest from RH and lowest from MI. Differences in k_CCEM between the devices were related to capsule aperture size while the differences between the materials were due to the powder bed structure. This approach provided an understanding of the rate at which powder mass emptied from dry powder inhaler devices and was proposed to be a powerful development tool for the future powder inhalers.     

A new configuration of two-level 48-pulse VSCs based STATCOM for voltage regulation

In this paper, a new configuration of STATCOM (Static Compensator) with constant DC link voltage is proposed for the voltage regulation. The proposed STATCOM consists of eight sets of two-level double-way Voltage Source Converters (VSCs). Each double-way VSC consists of two six-pulse VSCs connected through an open winding transformer unit. The phase-angle difference between these two VSCs is varied for the reactive power control. The proposed STATCOM model is developed using MATLAB/Simulink, SimPowerSystems (SPS) toolboxes and dynamic performance is studied for the change in the reference reactive power, the terminal voltage reference and voltage control under switching on an inductive and a capacitive loads. Simulation results are presented to demonstrate the voltage regulation capability of the STATCOM under these conditions.     

Prediction and assessment of demand response potential with coupon incentives in highly renewable power systems

Demand Response (DR) provides both operational and financial benefits to a variety of stakeholders in the power system. For example, in the deregulated market operated by the Electric Reliability Council of Texas (ERCOT), load serving entities (LSEs) usually purchase electricity from the wholesale market (either in day-ahead or real-time market) and sign fixed retail price contracts with their end-consumers. Therefore, incentivizing end-consumers’ load shift from peak to off-peak hours could benefit the LSE in terms of reducing its purchase of electricity under high prices from the real-time market. As the first-of-its-kind implementation of Coupon Incentive-based Demand Response (CIDR), the EnergyCoupon project provides end-consumers with dynamic time-of-use DR event announcements, individualized load reduction targets with EnergyCoupons as the incentive for meeting these targets, as well as periodic lotteries using these coupons as lottery tickets for winning dollar-value gifts. A number of methodologies are developed for this special type of DR program including price/baseline prediction, individualized target setting and a lottery mechanism. This paper summarizes the methodologies, design, critical findings, as well as the potential generalization of such an experiment. Comparison of the EnergyCoupon with a conventional Time-of-Use (TOU) price-based DR program is also conducted. Experimental results in the year 2017 show that by combining dynamic coupon offers with periodic lotteries, the effective cost for demand response providers in EnergyCoupon can be substantially reduced, while achieving a similar level of demand reduction as conventional DR programs.