MOVPE growth of (Al, Ga)InP-based laser structures monitored by real-time reflectance anisotropy spectroscopy

Using a specially-designed spectrometer enabling combined reflectance anisotropy spectroscopy (RAS) and reflectance measurements on rotating substrates in a commercial MOVPE reactor, we report the first full-spectroscopic RAS-monitoring of (Al,Ga)InP-based 650 nm laser growth. First, a spectral database was built up from systematic studies of AlGaInP RAS signatures for different Al compositions, doping levels and growth temperatures. These data are subsequently used for the interpretation of characteristic RAS fingerprints taken throughout the entire laser growth process. From the analysis of characteristic changes in the RAS spectra even small deviations from the optimum process (doping levels, composition, etc.) which would effect the performance of the final device can be detected.     

Upgrading of biomass by means of torrefaction

We present results on upgrading of wood and briquettes by means of torrefaction. The torrefied products showed significantly less smoking during combustion and a relatively faster rate of combustion. The weight and energy yeilds of torrefied wood are 66.7–83.3 and 76.5–89.6%, respectively; the corresponding values for sawdust briquettes are 76.3–93.8 and 83.1–95.3%, respectively.     

Fifth sustainable development goal gender equality in India: analysis by mathematics of uncertainty and covering of fuzzy graphs

Neural Computing and Applications - In the present situation, the sustainable development goal on “Gender Equality” (SDG 5) is a challenging problem over the entire globe, also in...     

Susceptibility of several varieties of soybean to Ephestia cautella (Walker) (Lepidoptera: Phycitidae)

Ephestia cautella (Walker) was reared on 39 varieties of soybean at 30 ± 1°C, 80 ± 5% r.h. and 12 hr light: 12 hr dark photoperiod. Larvae were reared individually on whole grains and flours of each variety and larval period, pupal period, per cent pupation and per cent adult formation were recorded. Larvae failed to develop on grains of 13 varieties while grains of Grant, Clark glabrous, Clark dense, Henry, Harrowmanchu and Hawkey-63 were highly susceptible to this pest. On the other hand larvae completed development successfully on all 39 varieties when seeds were ground into flours. It was also clear that UPSM-158 was somewhat tolerant to the attack of this pest while UPSM-120, Hawkey-63, Clark-63, Chippewa, UPSM-57, Harrowmanchu, Hampton, Goldsoy, Davis, Hood, and Kohachugatsu were also less efficient in supporting the development. Addition of 5% yeast to these varieties produced remarkable improvement in the quality of the diet which indicated that the flours of these varieties were deficient in one or more essential nutrients.     

Bayesian prediction for business mortality analysis

Summary This paper is concerned with business mortality analysis in a Bayesian setting. We assume that a businessman startsN businesses at different points of time and at a certain epoch referred to as the ‘present’, the failure times of the failed businesses and the survival times of the still surviving businesses are recorded. Bayesian prediction for business mortality or survival up to a future time pointt ₀ is made under the assumptions of a Weibull business survival distribution (WBSD) and the squared error loss function (SELF). The results are extended to the situation where one of the observed times of business failure may possibly be an outlier.     

Time of flight (TOF) spectrometer for accurate measurement of mass and angular distribution of fission fragments in heavy ion induced fission reactions

The performance of a dual time of flight (TOF) spectrometer using two 24 cm×10 cm area X–Y position sensitive Multi-Wire Proportional Counters (MWPC) is reported. Good separation of compound nuclear fission channel from elastic, quasi-elastic and non-compound fission channels have been achieved. Time calibration of the spectrometer using a technique, dependent on the detector independence of the mass or kinetic energy distributions gave a three times better mass resolutions compared to the conventional calibration technique using elastically scattered projectiles in a heavy ion induced fission reaction. Detail experimental methods in determining fission fragment mass and angular distribution have been presented and discussed.     

Sixth International Conference ACID ROCK DRAINAGE 2003

CONFERENCE

Sixth International Conference ACID ROCK DRAINAGE 2003     

Flux-based active filter controller

This paper presents a synchronous frame flux-based control method for a parallel active filter application. The flux-based controller directly implements the inverter switchings in the synchronous reference frame by a hysteresis rule-based carrier-less pulse-width modulation (PWM) strategy to achieve high current bandwidth. This paper addresses the issues and impact on parallel active filtering requirements for utility interface of commonly used harmonic front-ends. The synchronous frame flux-based controller provides additional insights for harmonic current compensation requirements. Simulation results provide the validation of the flux-based active filter controller to meet IEEE Standard 519 recommended harmonic standards for large rated nonlinear loads under balanced and unbalanced supply conditions     

Electrical and thermo-mechanical analysis of beam recovery system for megawatt power gyrotron

The paper presents the electrical and thermo-mechanical design of single stage beam recovery system for 120 GHz, 1 MW gyrotron. The electrical study shows that the cylindrical shape single stage beam recovery system enhances the efficiency by 66.26%. The maximum power deposited to collector in depressed collector operation is 0.48 MW for electronic efficiency, 30% and 1.44 MW for DC electron beam. The thermo-mechanical analysis has been performed to evaluate the water cooling system. The cooling system has capability of accommodating a peak wall loading, 0.9 kW/cm² at flow rate of 1500 l/min for safe operating time, 60 ms. Further, a high voltage analysis is also carried out to appraise the electric field distribution in the collector.