Rajeev Kumar

Improvement of voltage profile in Smart Grid using voltage sensitivity approach

The “Smart Grid” modernizes the aging power system and is characterised by two-way flow of electrical power and information within the network. Voltage stability is the prime concern of over stressed power system network. In Smart Grid, the overall voltage profile of the power network can be efficiently improved and thus avoids problems of voltage collapse and resultant blackouts. A simulation work has been done where reactive power requirement at different buses is calculated that improves the voltage profile of the overall network with the proposed approach using voltage sensitivity at the buses and effective locations for reactive power injection within the buses is determined. Also an approach is presented for capacitor bank operation associated to a bus. Voltage stability assessment considering different voltage stability indices is done under different system conditions that give vital information about the network (including weak buses & lines, maximum loading, most secure buses etc.) and these assessments can be very helpful in taking decisions to avoid uneven outages.

Effect of Heat Treatment Parameters on the Characteristics of Thin Wall Austempered Ductile Iron Casting

The technology of thin parts is necessary steps to designers for energy consuming equipment to choose accurate material based on material properties. Here austempering treatment process was utilized to acquire thin wall austempered ductile iron castings. The plate thickness (2-5) mm were austenitized at 900 °C for, 30 minutes took after by holding at 350°C, 400°C and 450°C inoculated by Ce-Ca-Al-S-O-FeSi,Zr-Mn-Ca-Al-Ba-FeSi and Sr-Al-Ca-FeSi at 0.2wt%,0.4wt% and 0.6wt% for 2,5 and 10 minutes for every temperature.The austempered samples are comparatively harder than the as-cast ductile iron plates. The micro hardness(HV20) also decreases with increase in austempering temperature for a given austempering time for thinner plates and also the micro hardness(HV20) is more for the samples treated at 350°C than those treated at 400°C and 450°C at 0.4wt% for a given austempering time. The yield strength and ultimate tensile strength of 2 mm thin wall austempered ductile iron are higher and ductility and impact strength are lower than that of as-cast 2 mm thin plate ductile iron inoculated by Ce-Ca-Al-S-O-FeSi compare to Zr-Mn-Ca-Al-Ba-FeSi and Sr-Al-Ca-FeSi at 0.4wt%. This may be attributed to the change in the structure change from ferrite-pearlite to austenite-bainite.

GuiTones-I: An audio-visual database of monophonic guitar tones

Automatic music transcription (AMT) is considered one of the most complex problems in music information retrieval (MIR). Many attempts of transcribing polyphonic music have been made in the past but monophonic tones, that build melodious music pieces, still remain largely untouched. The foremost approach is preparation of a database consisting of isolated and continuous monophonic sounds in order to proceed with the recognition and transcription of monophonic music pieces. In this paper one such audio-visual database of monophonic guitar tones for multi-modal signal processing has been introduced and evaluated for a test case of both online and offline recognition and transcription. The database comprises of recorded audio samples of first nine frets for all six strings and images of different ways in which the fretboard was held while playing these frets. A total of over 10,000 audio-visual samples have been recorded by 40 amateur and professional guitarists. The prepared database will be made available for free download under a CC BY-NC-SA 4.0 license and in DVDs at a nominal cost covering shipping and handling charges.