Main Spark Research Articles

Investor Perception of Cryptocurrency: A Moderating Role of Social Media on Decision-Making

In all probability, the field of finance has been studied at great length. Still and all, the behavior aspect of finance is relatively new; wherefore, it remains wide open for great exploration. Over the years, social media has grown taller by leaps and bounds. This served as the main spark plug for this study to explore the field of behavioral finance in the light of social media. Thence the aim of this research is to study the impact of information flowing from social media (SM) on investment decision-making and to see whether social media acts as a moderator between risk perception and decision-making. The study is quantitative in nature, and the data was culled using an adapted questionnaire. The sample size of this study, as computed through G power, was 64, and 102 investors actually recorded their responses. The data was analyzed through SPSS software using Ordinary Least Square (OLS).

Plasma triggered spark gap switch for multiple switch synchronization.

A four-electrode plasma based triggered spark gap switch is designed for pulsed power applications, which consists of an anode and cathode of a main spark gap switch and an anode and cathode for a trigger pin. The anode and cathode of the trigger pin are coaxially arranged, and the gap between electrodes is 25 μm. A trigger voltage of 200 V is applied across the trigger gap with the help of a switching insulated gate bipolar transistor. With the breakdown of the trigger gap, plasma is generated, which is injected into the main gap. The trigger pin is placed axisymmetric to the main spark gap in the cathode. The main discharge channel of the spark gap has 0.6 mm space between two electrodes, which is charged to 1000 V. When the spark gap is triggered, the discharge current has a peak value of 6.1 kA with a quarter cycle time period of 0.97 µs. The four-electrode spark gap switch results are compared with those of a three-electrode trigatron switch, which has the peak current of 6 kA with 1.01 µs as quarter-cycle time period. Four similar four-electrode spark gap switches are triggered with the same scheme and synchronized within 10 ns as peak values of currents with jitter as less than 5 ns.

Dynamic Characteristics of the Spark Channel Plasma in Nitrogen Trigatron Investigated by the Laser Mach–Zehnder Interferometer

The spark channel plasma generated in the atmospheric nitrogen trigatron is studied with the laser Mach–Zehnder (M–Z) interferometer. The development of the spark channel plasma is described by analyzing the temporal and spatial evolution of the plasma electron density from the interferograms. The regions of the shock wave and the plasma are distinguished by the phase shift. Different spatial distributions of the anodic and cathodic plasma channels are obtained. The anodic spark channel shows good axial symmetry with constant radial expansion velocity. On the periphery of the main spark channel, a secondary spark channel occurs simultaneously in the cathodic region. After the collision of the two channels, the stagnation forms in the overlapping region and the secondary channel merges with the main one gradually. The leftward expansion velocity of the secondary channel is higher than the rightward velocity of the main channel, but both of them are lower than that near anode. The speculation on the production of the secondary spark channel is given and its influence on the development of the spark discharge in the gap is discussed in this work.

Corona-stabilized gas spark gap switch for a double forming line with 300 kV working voltage

A high-current self-breakdown gas switch stabilized by corona preionization was developed for closing of 300 kV repetitively operated at 10 pps water insulated double-forming line (Blumlein) of a nanosecond electron accelerator. The switch is installed at the end of the Blumlein and is used for closing of outer of two coaxial lines. High stability of the self-breakdown voltage (within ±1%) at fast charging of Blumlein (during ≈1.4 μs) is achieved by gas preionization in the spark-gap by additional pulsed corona discharge. The spark-gap electrode system includes two main toroidal electrodes and an additional corona needle that is located in the cavity of one of them (negative during the operation). It combines two parallel gas discharge gaps – the main spark gap and an additional corona discharge gap. Separating the functions of the spark and corona gaps makes it possible to optimize the geometry of the electrodes of each gap and provide both the ability to switch high currents and high dynamic characteristics for a long operating time. Dried air is used as a working gas at pressure of 3-4 atm (abs.). Gas blowing system includes 4 gas inlets located at outer flange supporting the high voltage insulator (water-gas interface) and one outlet in the cavity of the grounded main electrode. This scheme of gas flow protects the insulator from deposition of electrode erosion products and minimizes gas flow (≈20 l/min) for stable operation of the switch by removing of the hot gas throw the cavity of the grounded electrode.The design of the switch together with the main results of the working tests will be presented and discussed.

Shot-to-shot stability of intense ion beam generation in a spiral diode with self-magnetic insulation

The results of the analysis of the gigawatt-power ion-beam generation in a spiral diode in the selfmagnetic insulation mode are presented. Investigations were carried out using the TEMP-4M accelerator that operated in the double-pulse formation mode: the first pulse is negative (300–500 ns, 150–200 kV) and the second is positive (150 ns, 250–300 kV). Spiral diodes of different designs were investigated under the conditions of a closed electron drift in the anode–cathode gap without an external magnetic field. The conditions for the formation and stabilization of a virtual cathode were analyzed, and experimental studies of its configurations in diodes of different designs were performed. The influence of the gradient and centrifugal electron drifts on the stability of the virtual cathode was analyzed. Investigations showed a high correlation between the energy density and total energy of a high-power ion beam with the value of the total charge that is transferred in the diode during the beam generation. This charge is mainly determined by the duration of the first voltage pulse. To increase the duration stability of the first voltage pulse (in the double-pulse mode), the first pulse that is fed to the load of the double forming line is also used to trigger the main spark gap. This provided a high stability of the ion-beam energy density in a pulse train. The long service life of ion diodes with self-magnetic insulation and an explosive-emission cathode (more than 106 pulses) and the high beamgeneration stability in a pulse train make them promising devices for use in various technological applications.

Investigation of the operating modes of a Blumlein pulse forming line

Results of studying the operating modes and shot-to-shot performance of a Blumlein pulse forming line (BPFL) at varying accelerator parameters are presented. The studies were performed on the TEMP-4M accelerator operating in the bipolar-pulse mode with the first negative plasma-generating pulse (150 kV, 400–500 ns) followed by the second positive accelerating pulse (200–250 kV, 120 ns). The operation of the BPFL was analyzed using a focusing strip-line ion diode with a magnetic self-insulation. When the BPFL operated in the bipolar-pulse mode, a high stability of the breakdown voltage of the preliminary spark gap was observed. The standard deviation in the pulse train did not exceed 2%. However, the stability of the main gasfilled spark gap performance was significantly worse (6–8%). To decrease the shot-to-shot variation in the breakdown voltage of the main spark gap, the first pulse arriving at the load of the BPFL was used for triggering the main spark gap.

Stabilization of ion beam generation in a diode with self-magnetic insulation in double-pulse mode

AbstractThe paper presents the results of statistical studies of ion beam generation in different geometry diodes with explosive emission cathode in a mode of self-magnetic insulation. The experiments were carried out using the TEMP-4M pulsed ion beam accelerator during its operation in both unipolar pulse mode (100 ns, 250–300 kV) and bipolar-pulse mode with the first negative (300–600 ns, 100–150 kV) followed by a second positive (120 ns, 250–300 kV) pulse. It is found that the standard deviation of the total energy and energy density of the beam does not exceed 10–11%, while the same shot-to-shot variation in ion current density was found to be 20–30%. The mechanism of the energy density stabilization from pulse to pulse may be associated with the charge exchange between accelerated ions and stationary molecules and formation of accelerated neutrals. We observed a high correlation between the energy density (or total beam energy) and the duration of the first voltage pulse. We performed analysis of Blumlein statistical performance when the Blumlein was terminated with a resistive load and with a self-magnetically insulated ion diode. A characteristic feature of Blumlein operation in the double-pulse mode is an excellent reproducibility of breakdown of the preliminary spark gap, the variation in breakdown voltage is <2%. At the same time, the shot-to-shot variation in the breakdown voltage of the main spark gap in both bipolar- and unipolar pulse mode is 3–4 times higher than that for the preliminary spark gap. To improve the statistical performance of the main spark gap we used the first voltage pulse at the output of Blumlein to trigger the main spark gap. The new trigatron-type regime of the main spark gap operation showed a better reproducibility of the first pulse duration, with the time jitter not exceeding 10 ns in a set of 50 pulses.

Improvement in the statistical operation of a Blumlein pulse forming line in bipolar pulse mode.

The paper presents the results of studies on shot-to-shot performance of a water Blumlein pulse forming line of 1-1.2 kJ of stored energy. The experiments were carried using the TEMP-4M pulsed ion beam accelerator during its operation in both unipolar pulse mode (150 ns, 250-300 kV) and bipolar-pulse mode with the first negative (300-600 ns, 100-150 kV) followed by a second positive (120 ns, 250-300 kV) pulse. The analysis was carried out for two cases when the Blumlein was terminated with a resistive load and with a self-magnetically insulated ion diode. It was found that in bipolar pulse mode the shot-to-shot variation in breakdown voltage of a preliminary spark gap is small, the standard deviation (1σ) does not exceed 2%. At the same time, the shot-to-shot variation in the breakdown voltage of the main spark gap in both bipolar-pulse and unipolar pulse mode is 3-4 times higher than that for the preliminary spark gap. To improve the statistical performance of the main spark gap we changed the regime of its operation from a self-triggered mode to an externally triggered mode. In the new arrangement the first voltage pulse at the output of Blumlein was used to trigger the main spark gap. The new trigatron-type regime of the main spark gap operation showed a good stability of breakdown voltage and thus allowed to stabilize the duration of the first pulse. The standard deviation of the breakdown voltage and duration of the first pulse did not exceed 2% for a set of 50 pulses. The externally triggered mode of the main gap operation also allowed for a decrease in the charging voltage of the Blumlein to a 0.9-0.95 of self-breakdown voltage of the main spark gap while the energy stored in Marx generator was decreased from 4 kJ to 2.5 kJ. At the same time the energy stored in Blumlein remained the same.

Characterisation of nickel alloy powders processed by spark plasma sintering

In this study, nickel alloy powders were consolidated by spark plasma sintering. Experiments were performed between 700 and 750°C temperature range under 50 MPa pressure with holding times from 5 to 10 min. In addition to these main spark plasma sintering parameters three different heating rates ranging from 100 to 235°C min−1 and two different particle size ranges (75–106 μm narrow size distribution and −45 μm wide size distribution) were used for the experiments. After sintering, the sliding wear behaviour of the samples was investigated. The results revealed that the density of the material increased with raising the sintering temperature and holding time. However, heating rate and particle size also played an important role in the densification and these parameters were investigated in detail.

Attitude of Diamond Entrepreneurs to Carry out Social Responsibility (A Study of Surat Diamond Organizations)

Profit motivation is the main spark of any economic activity, but at a macro level any economic activity is a part of social responsibility. The social responsibility demands that business should take some of the responsibilities and help to solve the allied social problems and issues and help to reach socio-political goals of business. Business should be an active guardian of society's conscience and problems. This study may help the business world to understand the need for social responsibility and people's expectations from business.

Impact of spark plug number of ground electrodes on engine stability

There are many different spark plug designs available in the market nowadays. Understanding the differences between them is beneficial in helping the engine to run properly and efficiently.In the present study, a group of four spark plugs with different number of ground electrodes were chosen to explore their impact on the engine performance and especially the combustion instability.The results showed that the amount of crossover of the ground strap, the dimensions of the ground strap and the gap width are the primary factors affecting the spark onset, flame initiation and kernel growth.The plug that performed the best was a plug with no ground electrode where the amount of heat loses was the lowest and there was no obstacles affecting the flame growth. The coefficient of variation (COV) of this spark plug type was the lowest of the four main test spark plugs.

Fuelling the fire

Rising temperatures are set to take over from direct human activity as the main spark of global wildfires.

Correlation between Brightness and Channel Currents of Electrical Discharges

Channel brightness of 500 mm long electrical discharges were measured by analyzing a set of digitized images taken by 3 cameras placed symmetrically around a discharge gap at a radial distance of 200 cm from the axis of the spark. The sparks were generated between a steel rod and a plane electrode. The distribution of the brightness across the channel represented a Gaussian distribution. A linear correlation was seen between the channel brightness measured by different cameras looking at the same spark channel. No correlation was seen between the channel brightness and the channel depth (direction perpendicular to the camera plane). The measured peak current and the brightness of the main spark channel show a high degree of correlation (R <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> =0.97). The sum of brightness of branches was equal to the brightness of the parent channel. One can use this result to calculate the relative distribution of branch currents in complex electrical discharges including natural lightning flashes. If the current in the parent channel is known, branch currents can be calculated by measuring the optical intensities using photographic techniques.

Design of a laser-triggered driver for fast capillary discharge

We are developing a new upgraded capillary discharge device. The assembled set-up consists of a Marx generator, a pulse forming line, a gas-filled laser-triggered spark gap and a ceramic capillary. The special attention has been paid to the design of the spark gap. The laser triggering of this spark gap ensures a very low jitter in comparison with the present capillary discharge device CAPEX, where the main spark gap works in a self-breakdown regime. The description of the assembled apparatus, the main predicted parameters of the designed device (such as capillary current, capillary current rise-rte, and/or voltage at the end of pulse forming line) are presented.

Schlieren studies of impulse breakdown in air gaps

The initial expansion of the leader channel and its subsequent cooling have been investigated in 10-30cm rod-plane gaps in air using a high-speed schlieren technique. The channel was found to expand to a maximum value of 0.6 mm and a shock wave, associated with the initial rapid expansion, was observed. When breakdown occurred, the main spark channel always followed the track of the leader. Thermal time-constant calculations indicate that the neutral gas density along the track of the leader would be reduced for periods of ~100μs. As reillumination intervals in the case of the stepped leader are shorter than this, it is suggested that enhanced ionisation in the hot column would have to be included in any explanation of the mechanism governing the propagation of the stepped-leader discharge.

Vacuum Ultraviolet High Resolution Spectroscopy Using a BRV Continuum Source

The authors describe improvements to a Ballofet-Romand-Vodar continuum source, viz., accurate synchronization of the main spark, better cooling of the anode. High resolution absorption spectra with a 10-m concave grating spectrograph are shown as examples of the performance thus obtained.

Effect of the Plasma-Jet in a Double Electrode Spark Gap

The mechanism of trigger action in a double electrode spark gap was investigated, clarifying the role of a plasma-jet ejected from the nozzle of the double electrode. Time lag characteristics were measured under several different voltages. Form and growth of a plasma-jet were observed with a suitable arrangement of a lens and a photo cell. The results show that the trigger mechanism may be assumed as follows: (1) A plasma-jet, ejected with a trigger spark, behaves itself like a protruding conductive stick. (2) Electric field strength in the gap is increased with growth of the jet. (3) A main spark is initiated in the space between the jet-front and the anti-electrode. (4) The critical distance between the jet-front and the anti-electrode is dependent on the voltage applied to the anti-electrode, and independent of gap length. Ions transported by the plasma-jet help to initiate the main spark. From these assumptions, sparking voltage and time lag characteristics, fluctuation of time lags, and effect of var...

Dosage de l'oxygène et de l'azote dans des échantillons de titane, au moyen d'une étincelle condensée dans le vide d'un type particulier

A description is given of a triggered three electrode vacuum spark, consisting of a main analytical spark initiated by a second auxiliary vacuum spark. The advantages of this arrangement for spectrochemical analysis are discussed, and some results are given concerning an application of this source to the determination of the oxygen and nitrogen contents in titanium samples in the far ultra-violet region.

The mechanism of the long spark

Study of the mechanism of the electric spark has been mainly confined to the short spark in homogeneous fields, or to the long spark provided by Nature in the form of the lightning flash. Following some early work of the author's on the characteristics of the impulse-voltage spark from a negatively or positively charged point electrode to earth, the author has further studied these discharges with the rotating camera to find the chronological sequence of discharge processes. Discharges preceding the main spark were observed irrespective of the polarity of the high-voltage electrode, the separation in time of the pre-discharge manifestation from the main spark being almost equal to the time-to-sparkover as recorded by the cathode-ray oscillograph. These discharges have been studied in air at atmospheric and lower pressures, and it has been shown that the pre-discharge is a “leader stroke” in the strict sense of the word as applied to the lightning discharge: a “leader” blazes an ionized path from the high-voltage electrode (of either polarity) to earth and is then followed by the return or main stroke of the spark from earth to the high-voltage electrode. Under certain conditions leader strokes have been shown to develop from both electrodes simultaneously. The leader stroke always exhibits branching in the direction of propagation; the main stroke follows some of the more important branches but does not develop fresh branches. The direction of branching of the spark discharge has been shown to furnish the criterion for the direction of propagation of the leader stroke.

Development of the Spark Discharge

SOME time ago, one of us1 photographed the long electric spark with a rotating camera and showed that a preliminary discharge occurred prior to the main spark, just as in the case of the lightning discharge studied by Prof. B. F. J. Schonland and others. The original photographs of the spark between a pointed high-voltage electrode and a plane earthed electrode showed the course of this leader discharge for about 20 per cent of the inter-electrode spacing the luminosity diminishing with increasing distance from the high-voltage electrode. The time interval between the leader and the main stroke corresponded to the time-to-sparkover as recorded on the oscillograph. Leader strokes preceded positive and negative discharges.