Some Electrical Characteristics of C3F8 Electrode Systems

This paper treats with corona discharges at normal pressure and at room temperature in C_3 F_3 and air with the following electrode systems: ¾” diameter sphere to 1 ¾” diameter plane, point to 1 ¾” diameter plane, point to point, 1” diameter sphere to 1” square plane, superimposed on a 1 ¾” diameter plate, 3/4” square plane to ¾” square plane (crossed and uncrossed), and ½” square plane to 1 ¾” diameter plane. The main discussions are: breakdown strength of these gases, mechanism of breakdown, and field mapping with the electrode systems. For transformers and circuit breakers insulation is most important for designing purposes. For transformers, oil is used for cooling and insulating. For circuit breakers, oil or some gases can be used for the purpose of quenching the arc. For these purposes, if gases are used, they should have high dielectric strength, noninflammability, etc. this paper discusses the dielectric strength of two gases and the effect in breakdown kV with different electrode systems at various gap settings. Oscillographic patterns of corona bursts for various electrode systems for the two gases are shown. Field analysis is also studied as it gives the physical concept of the system when the initiations of breakdown are confined to a single region of field, such as coiledges, clamps, and other sharp-edged electrode systems. Corona discharges are the transitory, faintly luminous, and audible glows which can be observed in a discharge gap, near the sparking value. Breakdown value of the gas depends upon the dielectric strength of the gas. It also depends upon electrode configuration; that is, concentrations of the filed. C_3 F_8 has high dielectric strength; mainly, due to the electronegativity of the gas. Air has less, as it is a mixture of gases

EPR and Optical Studies of Mo5+ Ions in Lithium Molybdoborate Glasses

Electron paramagnetic resonance (EPR) and optical absorption studies of Li2O–MoO3–B2O3 with varying concentrations of Li2O, MoO3 and B2O3 have been carried out at room temperature. Two series of glasses, one with constant MoO3 (CM) and another with constant borate (CB), have been investigated. Characteristic EPR spectra of Mo5+ have been observed centered around g ≅ 2.00, which are attributed to Mo5+ ion in an octahedral coordination sphere with an axial distortion. The spectra also show strong dependence on the concentration of Li2O and B2O3. Spin concentrations (N) and magnetic susceptibilities (χ) have been calculated. In the CM series, the N values decrease with increasing Li2O content up to 30 mol%, while in the CB series variation of N is found to increase initially up to 20 mol%, and with further increase in the Li2O content the N values tend to decrease. The variation of magnetic susceptibilities is almost similar to that observed with the variation of N. From the optical absorption spectra, an absorption edge (α) has been evaluated. In the CM series, the values of α show a blueshift. On the other hand, in the CB series a redshift is observed. The observed variations in spectral parameters are explained by considering the molybdoborate network. Addition of Li2O to the CM and CB series results in modification of [MoO6/2]0 → [MoOO5/2]− and [BO3/2]0 → [BO4/2]− → [BOO2/2]− groups, respectively, leading to creation of nonbridging oxygens. The optical basicity of the glasses has been evaluated in both the CM and the CB glasses. The optical basicity can be used to classify the covalent-to-ionic ratios of the glass, since an increasing optical basicity indicates decreasing covalency. It is observed that the covalency between Mo5+ ions and oxygen ligands increases in the CB series, whereas in the CM series the covalency between Mo5+ ions and oxygen ligands decreases

Improvement of Power Factor and Harmonic Reduction with VSC for HVDC System

This paper deals with analysis, simulation and control of a two level 48-pulse voltage source converter for High Voltage DC (HVDC) system. A set of two-level 6-pulse voltage source converters (VSCs) is used to form a 48-pulse converter operated at Fundamental Component of Switching Frequency (FCSF). The performance of the VSC system is improved in terms of reduced harmonic level at FCSF and THD (Total Harmonic Distortion). The performance of the VSC is studied to improve power factor and reduce harmonic distortion. Simulation results are presented for the proposed two level multi pulse converter

Review of Contemporary Literature on Machine Learning based Malware Analysis and Detection Strategies

Abstract: malicious software also known as malware are the critical security threat experienced by the current ear of internet and computer system users. The malwares can morph to access or control the system level operations in multiple dimensions. The traditional malware detection strategies detects by signatures, which are not capable to notify the unknown malwares. The machine learning models learns from the behavioral patterns of the existing malwares and attempts to notify the malwares with similar behavioral patterns, hence these strategies often succeeds to notify even about unknown malwares. This manuscript explored the detailed review of machine learning based malware detection strategies found in contemporary literature

Water-saving Rice Production Technologies in Krishna Western Delta Command of Andhra Pradesh – An Economic Analysis

The economic analysis of water-saving rice production technologies, viz. system of rice intensification (SRI), semi-dry and rotational irrigation vis-à-vis farmers’ practice has been carried out based on the study executed in Modukuru pilot area of Guntur district of Andhra Pradesh. Among the three water-saving rice production technologies analyzed, the total cost of cultivation has been recorded highest in SRI (Rs 58645/ha), followed by rotational (Rs 47140/ha) and semi-dry (Rs 39321/ha). But, the per hectare yield has been found highest in SRI (6.85 t), followed by semi-dry (6.66 t) and rotational (6.2 t), inferring that all the three technologies have recorded higher yields over farmers’ practice of 5.5 t/ha. However, the net returns and B-C ratio are maximum in semi-dry (Rs 43,484/ha; 1.11), followed by rotational (Rs 30,085; 0.64) and SRI (Rs 26,466/ha; 0.45) methods. Similarly, the water-use efficiency has been found highest in SRI (8.53 kg/ ha-mm), followed by semi-dry (8.02 kg/ha-mm) and rotational (7.33 kg/ ha-mm) methods, while the water-use efficiency benefit (Rs/ha-mm) has been recorded maximum in semi-dry (52.39), followed by SRI (42.08) and rotational (35.56) methods. With the initiation of Andhra Pradesh Water Management Project, Bapatla, the area under semi-dry rice cultivation has been found increasing over a period of four years, from 0.6 ha in 2004-2005 to 22 ha in 2007 -2008.Agricultural and Food Policy,

Service Level Agreements in Cloud Computing and Big Data

Now-a-days Most of the industries are having large volumes of data. Data has range of Tera bytes to Peta byte. Organizations are looking to handle the growth of data. Enterprises are using cloud deployments to address the big data and analytics with respect to the interaction between cloud and big data. This paper presents big data issues and research directions towards the ongoing work of processing of big data in the distributed environments

Stability Analysis of a Microwave Power Amplifier using Pole Zero Identification Method

This thesis demonstrates the use of pole zero identification method to stabilize a 2.32 - 2.37 GHz class AB power amplifier. In addition, the thesis presents a procedure to obtain values of stabilization components. Power amplifiers are used to drive transmitting antennas with high power in applications such as RADAR’s, cellular base stations and RF-driven lighting. They operate at large signal level to achieve these high output power levels. This increases the risk of potential oscillations in power amplifiers, which are undetectable using conventional linear stability factors. The oscillations degrade amplifier’s performance and may cause interference and transistor burnout. Non-applicability of linear stability factors for large-signal operation has led to development of new stability analysis methods such as Ohtomo, NDF and AG. Ability to detect oscillation due to large-signal has been the priority of these methods. A drawback is that, they are either complex to use or not fully complete in stabilizing a power amplifier. A recent method based on pole zero identification is shown to be rigorous and simple to use. However, this method requires a special additional software STability ANalysis(STAN) to identify poles and zeros of power amplifiers. This work utilized a simulation template in ADS 2011 to design the 2.32-2.37 GHz class AB power amplifier. The template requires measured load pull data of the transistor used in the amplifier design. The realized design has met maximum performance in first trial with little optimization. This design approach is useful to circumvent modeling problems in power transistors. However, the stability analysis is highly dependent on the transistor model accuracy. The designed and constructed class AB power amplifier in this work is unconditionally stable for small-signal operation and potentially unstable for large-signal operation. The amplifier is able to deliver an output power of 140 Watts with 15.2 dB gain and 42.08% efficiency at 2.345 GHz. Load pull measurements (peak power, peak gain and peak efficiency) of the amplifier and transistor used to design the amplifier are compared for design evaluation

Plant growth promoting bacteria from cow dung based biodynamic preparations

Not AvailableIndigenous formulations based on cow dung fermentation are commonly used in organic farming. Three biodynamic preparations viz., Panchagavya (PG), BD500 and ‘Cow pat pit’ (CPP) showed high counts of lactobacilli (109 ml-1) and yeasts (104 ml-1). Actinomycetes werepresent only in CPP (104 ml-1) and absent in the other two. Seven bacterial isolates from these ferments were identified by a polyphasic approach: Bacillus safensis (PG1), Bacillus cereus (PG2, PG4 PG5), Bacillus subtilis (BD2) Lysinibacillus xylanilyticus (BD3) and Bacillus licheniformis (CPP1). This is the first report of L. xylanilyticus and B. licheniformis in biodynamic preparations. Only three carbon sources—dextrose, sucrose and trehalose out of 21 tested were utilized by all the bacteria. None could utilizearabinose, dulcitol, galactose, inositol, inulin, melibiose,raffinose, rhamnose and sorbitol. All the strains producedindole acetic acid (1.8–3.7 lg ml-1 culture filtrate) and ammonia. None could fix nitrogen; but all except B. safensis and B. licheniformis could solubilize phosphorous from insoluble tri-calcium phosphate. All the strains except L. xylaniliticus exhibited antagonism to the plant pathogen Rhizoctonia bataticola whereas none could inhibit Sclerotium rolfsi. In green house experiment in soil microcosms, bacterial inoculation significantly promoted growth of maize; plant dry weight increased by *21 % due to inoculation with B. cereus (PG2). Results provide a basis forunderstanding the beneficial effects of biodynamic preparations and industrial deployment of the strainsNot Availabl

An 18 mer sequence in a rat 1.3 kbp EcoRI repeat detects genetic polymorphism in humans

DNA fingerprinting involves the typing of an individual's DNA content to produce somatically stable,individual-specific DNA fingerprints. This technique often uses hypervariable minisatellite (HVMS) sequences as the fingerprinting probe and has found extensive use in several disciplines. Recently, we sequenced a 1.3 kbp EcoRI repetitive DNA fragment, shown to harbour the meiotic DNA repair site(s) of rat pachytene spermatocytes. This 1.3 kbp clone contained four sequences sharing high homology to the various HVMS sequences reported in the literature. Here we show that one of the sequences can indeed detect polymorphism in human individuals and can be used for DNA fingerprinting