Automatic Restart Research Articles

Supervisor watchdog circuit to monitor an accelerator beam and control the safety interlock system

A supervisor watchdog circuit was developed to both monitor the dose and temperature at an accelerator beamline and provide signals to the safety interlock system of the accelerator. The implementation involved a D type flip-flop and subsequent logic gates to monitor the input and output signal states. It used a series of LEDs to inform the user about the state of the system and to enable identification of issues causing the beamline to shut down. The design allowed for a manual circuit restart to be performed to continue signal monitoring and accelerator operation. The supervisor watchdog circuit was installed at the tandem accelerator of the Reactor Materials Testing Laboratory at Queen’s University to monitor the beam properties during nuclear materials irradiation experiments. The scope for future improvements of the circuit such as automatic circuit restart in case of power fluctuations and addition of new signals is discussed.

Steady-State Operation Control of Gyrotrons in Support of Long Pulse Plasma Operation in EAST

In order to realize the 1000 s long pulse operation of the ECRH (Electron Cyclotron Resonance Heating) system on EAST (Experimental Advanced Superconducting Tokamak), we developed an ECRH steady-state operation control system. Four working modes were designed, namely manual restart mode, automatic restart mode, timed alternate operation mode, and protection trigger alternate operation mode. The FPGA-based NI cRIO was used as the control device, and the LabVIEW was used to write the program. The system has a quick response and accurate timing sequence, and can realize the long-pulse steady-state operation of the gyrotrons in EAST ECRH system. The steady-state operation control system has been verified in nearly two rounds of EAST experiments, helping EAST achieve the 1056 s long pulse discharge.

Аналіз роботи реле частоти із застосуванням цифрової системи тестування

We were given the task of automatically checking the characteristics of the digital frequency relay. To test and configure complex devices of relay protection and automation, which are digital frequency relays, there have been used special technical means using digital technology. Therefore, this problem is solved by creating algorithms to verify the characteristics of the operation of the typical and special characteristics of the digital frequency relay. On the basis of algorithms the specialized module of check of the frequency relay which became a subsystem of domestic digital test systems of check of devices of relay protection and automatic equipment “RZA-Tester”, “Relay-Tester” and “RTS-M” is created. The developed module allows to check almost all characteristics of the domestic digital frequency relay of the URCH-3M series in the modes of automatic frequency unloading, frequency automatic restart, automatic frequency unloading with blocking on speed of decrease in frequency, control of speed of decrease in frequency. The functional unit of the specialized module allows to check all the characteristics of the frequency relay in one cycle and significantly reduce its testing time. The frequency relay test module showed high efficiency at the stage of manufacturing the URCH-3M series frequency relay on the technological lines of the RELSIS research and production enterprise and during the adjustment of the frequency relay in the power systems of Ukraine.

The Maximum Common Subgraph Problem: A Parallel and Multi-Engine Approach

The maximum common subgraph of two graphs is the largest possible common subgraph, i.e., the common subgraph with as many vertices as possible. Even if this problem is very challenging, as it has been long proven NP-hard, its countless practical applications still motivates searching for exact solutions. This work discusses the possibility to extend an existing, very effective branch-and-bound procedure on parallel multi-core and many-core architectures. We analyze a parallel multi-core implementation that exploits a divide-and-conquer approach based on a thread pool, which does not deteriorate the original algorithmic efficiency and it minimizes data structure repetitions. We also extend the original algorithm to parallel many-core GPU architectures adopting the CUDA programming framework, and we show how to handle the heavily workload-unbalance and the massive data dependency. Then, we suggest new heuristics to reorder the adjacency matrix, to deal with “dead-ends”, and to randomize the search with automatic restarts. These heuristics can achieve significant speed-ups on specific instances, even if they may not be competitive with the original strategy on average. Finally, we propose a portfolio approach, which integrates all the different local search algorithms as component tools; such portfolio, rather than choosing the best tool for a given instance up-front, takes the decision on-line. The proposed approach drastically limits memory bandwidth constraints and avoids other typical portfolio fragility as CPU and GPU versions often show a complementary efficiency and run on separated platforms. Experimental results support the claims and motivate further research to better exploit GPUs in embedded task-intensive and multi-engine parallel applications.

An analysis of perceptions and support for Windows 10 Home Edition update features

Abstract Home computer users are regularly advised to install software updates to stay secure. Windows 10 Home Edition automatically downloads and installs updates, restarting the computer if needed. Automatic restarts can be managed through a number of features, such as ‘active hours’ (within which a computer will not restart to complete an update) or by setting a time for restart. Applications active prior to a restart can register with the operating system, to automatically restart once updates have been installed. This research investigates if the features Microsoft provides for managing updates on Windows 10 Home Edition are appropriate for computer owners. We build a model of Windows 10 update behaviour, identifying interaction points between update features and users. We contrast theory with reality in a survey with 93 Windows 10 Home users, capturing experiences and perceptions. While overall perceptions of updates were positive, the pattern of use of most participants was incompatible with the default ‘active hours’ settings (28% of participants knew of its existence). Participants were mostly unaware of quality (bug fix) updates, mostly perceiving that updates add features. Half of our participants reported unexpected restarts, while half also reported growing concern about the state of their device if an update took a long time. Those with previous negative update experiences had weaker beliefs about their ability to control updates than those who had not. To make the updates less disruptive, applications can request to be restarted by Windows after a reboot. Of the 47 commonly used applications which were tested, only two supported seamless continuation after a restart. Unsaved data were lost in 21 applications, and 14 appeared to rely on internal autosave features to capture unsaved data, but did not completely restore User Interface arrangements. We recommend that operating systems obtain explicit permission for restarts, consistently; there are opportunities for features such as active hours and update progress displays to learn from usage activity. At the same time, applications should be more resilient to restarts to reduce the burden on users to recover their activities.

Memetic algorithm for solving resource constrained project scheduling problems

The resource constrained project scheduling problem (RCPSP) has a wide variety of practical applications in construction, manufacturing, project planning, and other areas. Since the 1960s many optimization algorithms have been proposed to solve this NP-hard problem, and their performances are evaluated in well-known test problems with different complexities. Although it is desirable to find an algorithm which can provide promising solutions with reasonable computational efforts for any problem under consideration, no single algorithm can meet that condition. To deal with this challenge, we present a genetic algorithm based memetic algorithm (MA) for solving RCPSP. The algorithm is initiated by a critical path-based heuristic and a variant of the Nawaz, Enscore, and Ham (NEH) heuristic. The algorithm involves a similar block order crossover and a variable insertion based local search. An automatic restart scheme is also presented which assists the algorithm to escape from local optima. In addition, a design-of-experiment (DOE) method is used to determine the set of suitable parameters for the proposed MA. Numerical results, statistical analysis and comparisons with state-of-the-art algorithms demonstrate the effectiveness of the proposed approach.

A new algorithm for automating power supply of an AC traction network with a sectioning points on switches

The article considers modern sectioning points on contact network and determining the location of the damage, imthe switches, which differs by the introduction of new functions for plemented in the IntTer smart terminal. These new functions are determining a stable (or passing) short circuit in the disconnected deciding whether to perform a quick automatic restart of the circuit breakers after an emergency shutdown or finding the fault zone without testing the insulation of the contact network. The principle of operation of the functions under consideration is analyzed in the article. The limits of the optimum time of the current-free pause of the circuit breaker for automatic re-activation (AR) for each inter-substation zone are established. The paper describes the existing algorithm for automating power supply of an AC traction network (the normal reclosing algorithm) and indicates the unfavorable consequences from its application, in particular, related to the long time of the absence of voltage in the contact network. It was noted that the decision to reduce the voltage recovery time performed by introducing the function of determining the passing (or stable) short-circuit in the switched-off contact network in traction substations is due to the cost of additional high-voltage equipment and requires a rethinking. Thus, a new algorithm for automating the power supply of the traction network (the BAR algorithm) is presented, which is quite easily implemented at the modern sectioning post, which has voltage transformers for each supply line of the contact network, in contrast to the supply lines of the substation contact network and is caused by the transfer of the function of determining the passing (or steady ) short circuit to the sectioning point. In the article, the issue of performing the automatic reclosure of the power line of the traction substation is considered dependent on the successful operation of the BAR algorithm of the sectioning point. It is established that the most rational option is the implementation of a dependent automatic reclosing of a traction substation using telemechanics. The authors analyze the possibility of manufacturing compact sections of the ac contact network on the basis of single-phase re-closers OR-27.5 kV. It is noted that it is advisable to use a new automation scheme in conjunction with the sectionalization points on reclosers.

A descent hybrid modification of the Polak–Ribière–Polyak conjugate gradient method

Hybridizing self-adjusting approach of Dong et al. and three-term formulation of Zhang et al ., a nonlinear conjugate gradient method is proposed. The method reduces to the Polak–Ribiere–Polyak method under the exact line search and satisfies the sufficient descent condition independent of the line search and the objective function convexity. Similar to the Polak–Ribiere–Polyak method, the method possesses an automatic restart feature which avoids jamming. Global convergence analyses are conducted when the line search fulfills the popular Wolfe conditions as well as an Armijo-type condition. Numerical experiments are done on a set of CUTEr unconstrained optimization test problems. Results of comparisons show computational efficiency of the proposed method in the sense of Dolan–More performance profile.

アキュムレータを用いたアイドリングストップ方式による油圧源の省エネルギー

Recently, energy saving is very important because the environmental contamination and the shortage of energy resources have become a major problem in a number of fields including oil hydraulic systems. We previously proposed a pump unit driven by an electric motor with intermittent operation. This pump unit achieves electrical energy saving compared with conventional pump units under a wide range of driving condition. However, construction machines and vehicles mainly use an engine as a power source. In this study, we test the intermittent operation of a pump unit driven by an engine, and we achieve automatic engine restart by means of a hydraulic assist. We research an intermittently operated pump unit driven by a gasoline engine and achieve a saving in energy. In addition, we research the effect of accumulator volume and the stability of the engine restart.

White Paper Report of the 2012 RAD-AID Conference on International Radiology for Developing Countries: Planning the Implementation of Global Radiology

The RAD-AID Conference on International Radiology for Developing Countries is a yearly forum addressing global shortages of radiology that contribute to health care disparity. In this paper, the authors present key issues and consensus positions related to the planning, analyzing, implementing, and monitoring of radiology in limited-resource areas on the basis of presentations at the 2012 RAD-AID conference, to advocate for (1) economic development to build health care capacity, (2) multidisciplinary educational strategies, (3) innovative epidemiologic and infrastructural solutions tailored to community needs, (4) advanced technical solutions leveraging the widespread use of wireless telecommunications and phone-based portable devices, and (5) improved dialog across radiology and public health institutions for coordinating global health strategies.

Automatic restart of essential motors: A field evaluation using microprocessor-based protective relays

Industrial Facilities that employ numerous electrical motors for vital functions require either continuous operation, ride through, and/or automatic restart operation for abnormal conditions, such as momentary voltage loss, voltage dips, or other system voltage transients. With large essential motors, it is either impractical or not economical to provide an uninterruptible power source. Therefore, the next option to reduce the effects of transient interrupted service is to automatically sense the disturbance and initiate a sequenced restart of the essential motors on the basis of process requirements, motor acceleration characteristics, and power system capabilities. A customized logic algorithm that is programmed into microprocessor- based motor protection relays, eliminating additional undervoltage, control, timing relays, and wiring associated with traditional schemes, is described in this article. The algorithm is simulated during factory and site acceptance tests. This approach offers many user-configurable features that could be used in virtually any microprocessor-based relay protecting a medium-voltage induction motor. Also, the plant essential motors are prioritized into different categories, defining the order in which some essential motors are staggered and restarted together.

MCOR – Monte Carlo depletion code for reference LWR calculations

The MCOR (MCnp-kORigen) code system is a Monte Carlo based depletion system for reference fuel assembly and core calculations. The MCOR code is designed as an interfacing code that provides depletion capability to the LANL Monte Carlo code by coupling two codes: MCNP5 with the AREVA NP depletion code, KORIGEN. The physical quality of both codes is unchanged. The MCOR code system has been maintained and continuously enhanced since it was initially developed and validated. The verification of the coupling was made by evaluating the MCOR code against similar sophisticated code systems like MONTEBURNS, OCTOPUS and TRIPOLI-PEPIN. After its validation, the MCOR code has been further improved with important features. The MCOR code presents several valuable capabilities such as: (a) a predictor–corrector depletion algorithm, (b) utilization of KORIGEN as the depletion module, (c) individual depletion calculation of each burnup zone (no burnup zone grouping is required, which is particularly important for the modeling of gadolinium rings), and (d) on-line burnup cross-section generation by the Monte Carlo calculation for 88 isotopes and usage of the KORIGEN libraries for PWR and BWR typical spectra for the remaining isotopes. Besides the just mentioned capabilities, the MCOR code newest enhancements focus on the possibility of executing the MCNP5 calculation in sequential or parallel mode, a user-friendly automatic re-start capability, a modification of the burnup step size evaluation, and a post-processor and test-matrix, just to name the most important. The article describes the capabilities of the MCOR code system; from its design and development to its latest improvements and further ameliorations. Additionally, several interesting studies performed with MCOR are explained; its validation against MONTEBURNS, OCTOPUS and TRIPOLI-PEPIN; sensitivity studies with different voids and cross-section libraries; detailed comparison against measurement. Finally, the MCOR is used as a reference tool for benchmarking deterministic codes on the example of qualification of the spectral codes (APOLLO2-A and CASMO-4).

Thyristor rectifiers with digital control units based on microcontroller 80C196 for uninterruptible power supply systems

In this paper the thyristor rectifiers with digital control units developed in Institute 'Nikola Tesla' are presented. Digital control units of the types 'DRI 05' and 'DRI 07' are based on microcontroller 'Intel' 80C196KB16. Implemented technical solutions are described in detail, also as the experience derived from industrial exploitation of thyristor rectifiers. The new features implemented on the Institute's digital control units were triple automatic restart, detection of asymmetry of thyristor bridge and output voltage ripple, also as program hysteresis for alternation of voltage and current regulators. Responses of the implemented PI regulators of laboratory thyristor rectifier connected to RLC circuit are studied in detail. Results of examinations of rectifier's output current and voltage waveforms in industrial facilities are also presented.

Optimization potential of the vehicle launch performance for start—stop micro-hybrid vehicles

One of the primary features of a micro-hybrid vehicle is the automatic shutdown and restart of the engine to avoid engine idling when the vehicle is at rest. The system strategy and its calibration have important significance for the driveability of the vehicle in terms of the vehicle launch behaviour. An unsatisfactory vehicle launch is defined as an inferior launch performance of the vehicle resulting in a stalled engine, a launch with negative vehicle acceleration, and an aborted engine restart due to the inability of the vehicle to provide torque as demanded by the user. In this research, micro-hybrid system optimization for reduction in the percentage of impaired vehicle launch events in real-world usage has been conducted on a start—stop vehicle. The design for the six-sigma process was followed for the optimization study. A high-fidelity electrical and powertrain system and a longitudinal vehicle dynamics model for a start—stop vehicle have been developed. The model has been validated with experimental data. The drivers' behaviour for vehicle launch events from a customer clinic of start—stop vehicles has been used as an input to the model. Using design of experiments, the system has been optimized to maximize the percentage of successful launch events in real-world usage.

Making sense of log management for security purposes – an approach to best practice log collection, analysis and management

Every computer action registers a log somewhere – giving a rich source of data that can help businesses identify any trace of corruption within their networks. Log collection is also a strong component of keeping in line with legislation such as Sarbanes-Oxley, HIPAA, GLBA in the US, and the European Data Protection Directive in the EU. Mathieu Gorge looks at what logs organizations need to keep and what standards require their storage. He recommends proactive monitoring of firewalls, anti-virus, VPNs and IDS logs among other security systems. The main goal is to link a transaction back to an individual user in order to perform a forensic investigation. But it is important to be wary, as some countries do not allow companies to monitor staff usage of IT systems. See page 3 on how the European court ruled that a British college's monitoring of one employee was a breach of human rights. Therefore, linking a log with a person's actions may not stand up in court. Gorge says logs can give as good an insight into external attacks as well as internally driven ones. Logs should be analyzed for the following: •User account activity: creation, elevation of privilege, changes, inactivity.•Client requests and server response.•Operational status: shutdown (planned or unplanned), system failure and automatic restart.•Usage information and trends – basic user behaviour analysis. User account activity: creation, elevation of privilege, changes, inactivity. Client requests and server response. Operational status: shutdown (planned or unplanned), system failure and automatic restart. Usage information and trends – basic user behaviour analysis. It is best practice to collect, store and analyze logs with a view to being able to get complete, accurate and verifiable information. This will improve the organization's ability to comply with key standards and legislation as regards e-evidence. It could save an organization from potential liability and repair costs and will give visibility over mission critical and security systems, performance and usage. The main advice is to remain proactive so as to be able to respond to a security incident and comply with legal requests should anything happen. Mathieu Gorge looks at what logs can do for your business and how governance demands them.

On Accelerated Random Search

A new variant of pure random search (PRS) for function optimization is introduced. The basic finite-descent accelerated random search (ARS) algorithm is simple: the search is confined to shrinking neighborhoods of a previous record-generating value, with the search neighborhood reinitialized to the entire space when a new record is found. Local maxima are avoided by including an automatic restart feature which reinitializes the search neighborhood after some number of shrink steps have been performed. One goal of this article is to provide rigorous mathematical comparisons of ARS to PRS. It is shown that the sequence produced by the ARS process converges, with probability one, to the maximum of a continuous objective function faster than that of the PRS process by adjustably large multiples of the time step (Theorem). Regarding an infinite-descent (no automatic restart) version of ARS, it is shown that if the objective function satisfies a local nonflatness condition, then the right tails of the distributions of inter-record times are exponentially smaller than those of PRS (Theorem). Performance comparisons between ARS, PRS, and three quasi-Newton-type optimization routines are reported in attempting to find extrema of (i) each of a small collection of standard test functions of two variables, and (ii) d-dimensional polynomials with random roots. Also reported is a three-way performance comparison between ARS, PRS, and a simulated annealing algorithm in attempting to solve traveling salesman problems.

PEGASUS 5: An Automated Preprocessor for Overset-Grid Computational Fluid Dynamics

An all new, automated version of the PEGASUS software has been developed and tested. PEGASUS provides the hole-cutting and connectivity information between overlapping grids and is used as the final part of the grid-generation process for overset-grid computational fluid dynamics approaches. The new PEGASUS code (Version 5) has many new features: automated hole cutting, a projection scheme for fixing small discretization errors in overset surfaces, more efficient interpolation search methods using an alternating digital tree and a stencil-jumping scheme, hole-size optimization based on adding additional layers of fringe points, and an automatic restart capability. The new code has also been parallelized using the message-passing interface standard. The parallelization performance provides efficient speedup of the execution time by an order of magnitude, and up to a factor of 30 for very large problems. The results of two example cases are presented: a three-element high-lift airfoil and a complete Boeing 777-200 aircraft in a high-lift landing configuration

Ultrasonic diagnostic imaging system with automatic restart and response

An ultrasound system is described which will automatically turn on at predetermined times and condition itself for a specific scanning procedure. The system can also respond to remote queries even when not in service. Such an ultrasound system can be turned off at night, respond to external queries during the night, and be ready for use at a desired time the next day, without operator intervention, thereby conserving energy while maintaining efficiency.

A Fault Tolerance Solution for Sequential and MPI Applications on the Grid

The Grid community has made an important effort in developing middleware to provide different functionalities, such as resource discovery, resource management, job submission or execution monitoring. As part of this effort this paper addresses the design and implementation of an architecture (CPPC-G) based on services to manage the execution of fault tolerant applications on Grids. The CPPC (Con­troller/Pre­com­piler for Portable Checkpointing) framework is used to insert checkpoint instrumentation into the code of sequential and MPI applications. Designed services will be in charge of submission and monitoring of the execution of CPPC-instrumented applications, management of checkpoint files generated by the fault-tolerant applications, and detection and automatic restart of failed executions.

Availability in parallel systems: Automatic process restart

Parallel and clustered architectures are increasingly being used as a foundation for high-capacity servers. At the same time, the availability expectations are also rising rapidly, since the effects of down time become more apparent and have higher economic consequences for larger systems. The use of parallel structures generally implies more hardware and software components. The presence of more and larger components increases the chances that an individual component will fail, and that failure has the potential to hurt the overall availability of the system. This paper discusses the use of “restart techniques” as an important strategy in providing increased availability in a parallel structure. The paper covers a set of functions that have been developed for the S/390® Parallel Sysplex™.