Arc Control Research Articles

MAG welding of S700MC steel used in transport means with the operation of low arc welding method

Manufacturers of welding equipment strive to develop the most efficient, cost-effective and easy to process welding methods. This necessity is also related to welding of new, often hard-to-weld steel types. The article aims to present the possibility of welding a high-strength S700MC steel with an increased yield point using MAG (135) process and a blowtorch with an intelligent arc control. The blowtorch allows to reduce input energy and reduce splinters while maintaining the mechanical properties of the material. The S700MC steel has been selected for the tests purposefully, as it may create welding problems in order to maintain high strength and increased yield point. The applied technology provided lower power consumption compared to traditional welding machines and joints with very good mechanical properties were achieved.

Efficient methane-to-acetylene conversion using low-current arcs.

The proliferation of natural gas production had led to increased utilization of methane as a raw material for chemicals. The most significant bottleneck in this process is the high activation energy of methane. This paper reports the direct conversion of methane to acetylene in a novel rotating arc driven by AC electrical power. By feeding a sufficiently high concentration of CH4 (greater than 43%) diluted in H2 (the discharge gas) through the arc column, a low specific energy requirement (SER) of 10.2 kW h kg−1 C2H2 was achieved. The use of hydrogen as the discharge gas strongly suppressed soot formation during the methane conversion process under high methane concentration conditions, resulting in a carbon balance of greater than 95% and a C2H2 selectivity of greater than 90% while maintaining a methane conversion rate of greater than 70%, depending on the conditions. The novel rotating arc enabled the elongation of the arc column itself, which controlled heat loss and improved the energy use for reaction. The ability to control the arc length based on low-current type arc generation has additional benefits for reaction enhancement. These results demonstrate that arc control, optimization of the reaction conditions, and a full understanding of reaction pathway are viable means for the energy-efficient direct conversion of methane to acetylene.

Run control of straight and arc of ACV by single controller using image information

Run control of straight and arc of ACV by single controller using image information

ATLAS utilisation of the Czech national HPC center

The Czech national HPC center IT4Innovations located in Ostrava provides two HPC systems, Anselm and Salomon. The Salomon HPC is amongst the hundred most powerful supercomputers on Earth since its commissioning in 2015. Both clusters were tested for usage by the ATLAS experiment for running simulation jobs. Several thousand core hours were allocatedto the project for tests, but the main aim is to use free resources waitigfor large parallel jobs of other users. Multiple strategies for ATLAS job execution were tested on the Salomon and Anselm HPCs. The solution described herein is based on the ATLAS experience with other HPC sites. ARC Compute Element (ARCCE) installed at the grid site in Prague is used for job submission to Salomon. The ATLAS production system submits jobs to the ARC-Evia ARC Control Tower (aCT). The ARC-CE processes job requirements from aTand creates a script for a batch system which is then executed via ssh. Sshfs is used to share scripts and input files between the site and the HPC cluster. The software used to run jobs is rsynced from the site's CVMFS installation to the HPC's scratch space every day to ensure availabiliy of recent software. Using this setting, opportunistic capacity of the Salomon HPC was exploited.

Research on Arc Length Control Technology of Double Closed-loop for Pulsed MIG Welding

This paper presents a pulsed MIG welding arc length control method based on fuzzy control, which can better realize the dynamic control of arc and ensure arc length stability. In this system, a double-closed-loop control scheme is proposed, a variable-parameter PI control method is used, and a two-dimensional fuzzy controller of an arc-length loop is designed. Both the simulation and the experimental results show that when the distance between the welding gun and the workpiece changes, the arc length can reach a new balance and stable state after 9 pulse periods. The arc length control technology of double closed-loop for pulsed MIG welding is verified feasible in this paper.

Statistical Tool for the Control of ARC of Human Resources of the Strategic Planning of the University of Guantánamo

Statistical Tool for the Control of ARC of Human Resources of the Strategic Planning of the University of Guantánamo

Chemogenomic analysis reveals key role for lysine acetylation in regulating Arc stability

The role of Arc in synaptic plasticity and memory consolidation has been investigated for many years with recent evidence that defects in the expression or activity of this immediate-early gene may also contribute to the pathophysiology of brain disorders including schizophrenia and fragile X syndrome. These results bring forward the concept that reversing Arc abnormalities could provide an avenue to improve cognitive or neurological impairments in different disease contexts, but how to achieve this therapeutic objective has remained elusive. Here, we present results from a chemogenomic screen that probed a mechanistically diverse library of small molecules for modulators of BDNF-induced Arc expression in primary cortical neurons. This effort identified compounds with a range of influences on Arc, including promoting its acetylation—a previously uncharacterized post-translational modification of this protein. Together, our data provide insights into the control of Arc that could be targeted to harness neuroplasticity for clinical applications.

Influence of the pulsed AMF arc control on the vacuum arc and post arc characteristic in vacuum interrupters

The paper investigates the influence of the pulsed AMF arc control on the vacuum arc and the post arc characteristic to reveal the mechanism of AMF arc control in different control time and find the proper AMF arc control. The pulsed AMF control system is designed and the pulse width is adjusted from 1.5 ms to 10 ms by changing the capacitors. The test circuit is set up in the synthetic test circuit and the test vacuum interrupter (VI) is transparent in order to observe the development of the vacuum arc by the high speed CMOS camera. The rated voltage and current of the test VI is 10 kV and 25 kA respectively. The post arc current of the test VI is measured in order to analyze the post arc characteristic, such as the post arc charge, post arc conductance and dynamic dielectric strength. The development of vacuum arc and the post arc characteristic influenced by the pulse width, magnitude and control time of the pulsed AMF is obtained, which is useful to special magnetic contacts design.

Computer system for automatic control of arc surfacing processes using electrode wires

Computer system for automatic control of arc surfacing processes using electrode wires

Компьютерная система автоматического управления процессов дуговой наплавки электродными проволоками

Компьютерная система автоматического управления процессов дуговой наплавки электродными проволоками

Rotating Constricted Switching Arcs Burning in Gas and in Vacuum

The method of controlling high-current switching arcs by transverse magnetic fields (TMF) forcing the constricted arc to rotate in a contact system is being applied successfully to improve the breaking capability of vacuum interrupters and gas circuit breakers. We describe the behavior of magnetically driven switching arcs in vacuum and in gas environment. We report on experiments using high-velocity videography, magnetic probes, and spectroscopy; they deliver the velocity, the temperature and the voltage of an arc. We present models and simulations of the moving constricted arc burning in metal vapor and in air. And we describe a particular switching application of TMF arc control and explain a scaling law of the contact size with the current interruption capability.

Estimation of excitation forces for wave energy converters control using pressure measurements

ABSTRACTMost control algorithms of wave energy converters require prediction of wave elevation or excitation force for a short future horizon, to compute the control in an optimal sense. This paper presents an approach that requires the estimation of the excitation force and its derivatives at present time with no need for prediction. An extended Kalman filter is implemented to estimate the excitation force. The measurements in this approach are selected to be the pressures at discrete points on the buoy surface, in addition to the buoy heave position. The pressures on the buoy surface are more directly related to the excitation force on the buoy as opposed to wave elevation in front of the buoy. These pressure measurements are also more accurate and easier to obtain. A singular arc control is implemented to compute the steady-state control using the estimated excitation force. The estimated excitation force is expressed in the Laplace domain and substituted in the control, before the latter is transformed to the time domain. Numerical simulations are presented for a Bretschneider wave case study.

Influence of the AMF Arc Control on Voltage Distribution of Double-Break VCBs

This paper investigates the influence of the axial magnetic field (AMF) arc control on voltage distribution (VD) of double-break vacuum circuit breakers (VCBs) in order to gain balanced VD, and thus enhance the breaking capacity. The interaction of vacuum arc plasma, postarc current (PAC), and AMF is discussed. We conduct the breaking test of double-break VCBs with externally applied AMF of a different pulsewidth, magnitude, and a different moment. The PAC, postarc charge, and the VD are measured to analyze the relationship between the AMF arc control and the VD. The optimal AMF arc control and the relationship between the AMF magnitude and the unbalanced voltage ratio are gained when the grading capacitors were 400 pF. The experimental test showed that the proper AMF arc control can improve the unbalanced VD. The mechanism is that the proper AMF arc control can make the postarc charge small and stable, so the unbalanced postarc charge, which caused the unbalanced VD is limited.

Aligning organizational priorities with ARC to improve youth mental health service outcomes.

The Availability, Responsiveness, and Continuity (ARC) organizational intervention is designed to improve community-based youth mental health services by aligning organizational priorities with 5 principles of effective service organizations (i.e., mission driven, results oriented, improvement directed, relationship centered, participation based). This study assessed the effect of the ARC intervention on youth outcomes and the mediating role of organizational priorities as a mechanism linking the ARC intervention to outcomes. Fourteen community-based mental health agencies in a midwestern metropolis along with 475 clinicians and 605 youth (ages 5-18) served by those agencies were randomly assigned to the 3-year ARC intervention or control condition. The agencies' priorities were measured with the ARC Principles Questionnaire (APQ) completed by clinicians at the end of the intervention. Youth outcomes were measured as total problems in psychosocial functioning described by their caregivers using the Shortform Assessment for Children (SAC) at 6 monthly intervals. The rate of improvement in youths' psychosocial functioning in agencies assigned to the ARC condition was 1.6 times the rate of improvement in agencies assigned to the control condition, creating a standardized difference in functioning of d = .23 between the 2 groups at the 6-month follow-up. The effect on youth outcomes was fully mediated by the alignment of organizational priorities described in the 5 ARC principles (d = .21). The ARC organizational intervention improves youth outcomes by aligning organizational priorities with the 5 ARC principles. The findings suggest that organizational priorities explain why some community mental health agencies are more effective than others. (PsycINFO Database Record

Auxiliary particle filter-model predictive control of the vacuum arc remelting process

Solidification control is required for the suppression of segregation defects in vacuum arc remelting of superalloys. In recent years, process controllers for the VAR process have been proposed based on linear models, which are known to be inaccurate in highly-dynamic conditions, e.g. start-up, hot-top and melt rate perturbations. A novel controller is proposed using auxiliary particle filter-model predictive control based on a nonlinear stochastic model. The auxiliary particle filter approximates the probability of the state, which is fed to a model predictive controller that returns an optimal control signal. For simplicity, the estimation and control problems are solved using Sequential Monte Carlo (SMC) methods. The validity of this approach is verified for a 430 mm (17 in) diameter Alloy 718 electrode melted into a 510 mm (20 in) diameter ingot. Simulation shows a more accurate and smoother performance than the one obtained with an earlier version of the controller.

SU‐F‐T‐531: Determination of Site‐Specific Dynamic‐Jaw Versus Static‐Jaw RapidArc Delivery

Purpose:Dynamic‐jaw tracking maximizes the area blocked by both jaw and MLC in RapidArc. We developed a method to quantify jaw tracking.Methods:An Eclipse Scripting API (ESAPI) was used to export beam parameters for each arc's control points. The specific beam parameters extracted were: gantry angle, control point number, meterset, x‐jaw positions, y‐jaw positions, MLC bank‐number, MLC leaf‐number, and MLC leaf‐position. Each arc contained 178 control points with 120 MLC positions. MATLAB routines were written to process these parameters in order to calculate both the beam aperture (unblocked) size for each control point. An average aperture size was weighted by meterset. Jaw factor was defined as the ratio between dynamic‐jaw to static‐jaw aperture size. Jaw factor was determined for forty retrospectively replanned patients treated with static‐jaw delivery sites including lung, brain, prostate, H&N, rectum, and bladder.Results:Most patients had multiple arcs and reduced‐field boosts, resulting in 151 fields. Of these, the lowest (0.4722) and highest (0.9622) jaw factor was observed in prostate and rectal cases, respectively. The median jaw factor was 0.7917 meaning there is the potential unincreased blocking by 20%. Clinically, the dynamic‐jaw tracking represents an area surrounding the target which would receive MLC‐only leakage transmission of 1.68% versus 0.1% with jaws. Jaw‐tracking was more pronounced at areas farther from the target. In prostate patients, the rectum and bladder had 5.5% and 6.3% lower mean dose, respectively; the structures closer to the prostate such as the rectum and bladder both had 1.4% lower mean dose.Conclusion:A custom ESAPI script was coupled with a MATLAB routine in order to extract beam parameters from static‐jaw plans and their replanned dynamic‐jaw deliveries. The effects were quantified using jaw factor which is the ratio between the meterset weighted aperture size for dynamic‐jaw fields versus static‐jaw fields.

水プラズマのアーク制御による廃棄物分解の高効率化

A water plasma was generated by DC arc discharge between a hafnium cathode and a cupper anode. Arc fluctuation in the water plasma was examined by arc image observation synchronized with voltage measurement. Axial and radial extent of the arc was observed by high-speed camera. The effect of anode nozzle length was investigated to control the arc fluctuation. Radial extent of arc was suppressed when anode nozzle length increased. Therefore, available arc energy was increased when anode nozzle length was more than 7 mm. Decomposition rate of the treated material can be improved by arc control.

ARC Control Tower: A flexible generic distributed job management framework

While current grid middleware implementations are quite advanced in terms of connecting jobs to resources, their client tools are generally quite minimal and features for managing large sets of jobs are left to the user to implement. The ARC Control Tower (aCT) is a very flexible job management framework that can be run on anything from a single users laptop to a multi-server distributed setup. aCT was originally designed to enable ATLAS jobs to be submitted to the ARC CE. However, with the recent redesign of aCT where the ATLAS specific elements are clearly separated from the ARC job management parts, the control tower can now easily be reused as a flexible generic distributed job manager for other communities. This paper will give a detailed explanation how aCT works as a job management framework and go through the steps needed to create a simple job manager using aCT and show that it can easily manage thousands of jobs.

Dynamic Resource Allocation with the arcControlTower

Distributed computing resources available for high-energy physics research are becoming less dedicated to one type of workflow and researchers workloads are increasingly exploiting modern computing technologies such as parallelism. The current pilot job management model used by many experiments relies on static dedicated resources and cannot easily adapt to these changes. The model used for ATLAS in Nordic countries and some other places enables a flexible job management system based on dynamic resources allocation. Rather than a fixed set of resources managed centrally, the model allows resources to be requested on the fly. The ARC Computing Element (ARC-CE) and ARC Control Tower (aCT) are the key components of the model. The aCT requests jobs from the ATLAS job management system (PanDA) and submits a fully-formed job description to ARC-CEs. ARC-CE can then dynamically request the required resources from the underlying batch system. In this paper we describe the architecture of the model and the experience of running many millions of ATLAS jobs on it.

Increasing clinicians' EBT exploration and preparation behavior in youth mental health services by changing organizational culture with ARC

ObjectiveClinician EBT exploration and preparation behavior is essential to the ongoing implementation of new EBTs. This study examined the effect of the ARC organizational intervention on clinician EBT exploration and preparation behavior and assessed the mediating role of organizational culture as a linking mechanism. MethodFourteen community mental health agencies that serve youth in a major Midwestern metropolis along with 475 clinicians who worked in those agencies, were randomly assigned to either the three-year ARC intervention or control condition. Organizational culture was assessed with the Organizational Social Context (OSC) measure at baseline and follow-up. EBT exploration and preparation behavior was measured as clinician participation in nine separate community EBT workshops held over a three-year period. ResultsThere was 69 percent greater odds (OR = 1.69, p < .003) of clinicians in the ARC condition (versus control) attending each subsequent workshop. Workshop attendance in the control group remained under two percent and declined over three years while attendance in the ARC condition grew from 3.6 percent in the first workshop to 12 percent in the ninth and final workshop. Improvement in proficient organizational culture mediated the positive effect of the ARC intervention on clinicians' workshop attendance (a × b = .21; 95% CI:LL = .05, UL = .40). ConclusionsOrganizational interventions that create proficient mental health agency cultures can increase clinician EBT exploration and preparation behavior that is essential to the ongoing implementation of new EBTs in community youth mental health settings.