Delayless acceleration measurement method for motion control applications

Energy Technology Data Exchange (ETDEWEB)

Vaeliviita, S.; Ovaska, S.J. [Helsinki University of Technology, Otaniemi (Finland). Institute of Intelligent Power Electronics

1997-12-31

Delayless and accurate sensing of angular acceleration can improve the performance of motion control in motor drives. Acceleration control is, however, seldom implemented in practical drive systems due to prohibitively high costs or unsatisfactory results of most acceleration measurement methods. In this paper we propose an efficient and accurate acceleration measurement method based on direct differentiation of the corresponding velocity signal. Polynomial predictive filtering is used to smooth the resulting noisy signal without delay. This type of prediction is justified by noticing that a low-degree polynomial can usually be fitted into the primary acceleration curve. No additional hardware is required to implement the procedure if the velocity signal is already available. The performance of the acceleration measurement method is evaluated by applying it to a demanding motion control application. (orig.) 12 refs.

Control problems in very large accelerators

International Nuclear Information System (INIS)

Crowley-Milling, M.C.

1985-06-01

There is no fundamental difference of kind in the control requirements between a small and a large accelerator since they are built of the same types of components, which individually have similar control inputs and outputs. The main difference is one of scale; the large machine has many more components of each type, and the distances involved are much greater. Both of these factors must be taken into account in determining the optimum way of carrying out the control functions. Small machines should use standard equipment and software for control as much as possible, as special developments for small quantities cannot normally be justified if all costs are taken into account. On the other hand, the very great number of devices needed for a large machine means that, if special developments can result in simplification, they may make possible an appreciable reduction in the control equipment costs. It is the purpose of this report to look at the special control problems of large accelerators, which the author shall arbitarily define as those with a length of circumference in excess of 10 km, and point out where special developments, or the adoption of developments from outside the accelerator control field, can be of assistance in minimizing the cost of the control system. Most of the first part of this report was presented as a paper to the 1985 Particle Accelerator Conference. It has now been extended to include a discussion on the special case of the controls for the SSC

Modern control techniques for accelerators

International Nuclear Information System (INIS)

Goodwin, R.W.; Shea, M.F.

1984-05-01

Beginning in the mid to late sixties, most new accelerators were designed to include computer based control systems. Although each installation differed in detail, the technology of the sixties and early to mid seventies dictated an architecture that was essentially the same for the control systems of that era. A mini-computer was connected to the hardware and to a console. Two developments have changed the architecture of modern systems: (a) the microprocessor and (b) local area networks. This paper discusses these two developments and demonstrates their impact on control system design and implementation by way of describing a possible architecture for any size of accelerator. Both hardware and software aspects are included

Architecture of the modern accelerator control system

International Nuclear Information System (INIS)

Samardzic, B.; Drndarevic, V.

2000-01-01

Well defined concept of the system and construction plan are the important conditions for the successful realization of the accelerator control system. In this paper the modern concept of accelerator control system as well as guidelines for its efficient development have been presented. Described concept could be applied for the design of control systems for other types of facilities for experimental physics and for industrial process control. (author)

Accelerator-control-system interface for intelligent power supplies

International Nuclear Information System (INIS)

Cohen, S.

1992-01-01

A number of high-current high-precision magnet power supplies have been installed at the proton storage ring at the Los Alamos National Laboratory Accelerator Complex. The units replace existing supplies, powering large dipole magnets in the ring. These bending magnets require a high-current supply that is precise and stable. The control and interface design for these power supplies represents a departure from all others on-site. The supplies have sophisticated microprocessor control on-board and communicate with the accelerator control system via RS-422 (serial communications). The units, built by Alpha Scientific Electronics, Hayward, CA use a high-level ASCII control protocol. The low-level ''front-end'' software used by the accelerator control system has been written to accommodate these new devices. They communicate with the control system through a terminal server port connected to the site-wide ethernet backbone. Details of the software implementation for the analog and digital control of the supplies through the accelerator control system will be presented

Neural Networks for Modeling and Control of Particle Accelerators

CERN Document Server

Edelen, A.L.; Chase, B.E.; Edstrom, D.; Milton, S.V.; Stabile, P.

2016-01-01

We describe some of the challenges of particle accelerator control, highlight recent advances in neural network techniques, discuss some promising avenues for incorporating neural networks into particle accelerator control systems, and describe a neural network-based control system that is being developed for resonance control of an RF electron gun at the Fermilab Accelerator Science and Technology (FAST) facility, including initial experimental results from a benchmark controller.

Innovative Digitally Controlled Particle Accelerator Magnet Power Supply

DEFF Research Database (Denmark)

Nielsen, Rasmus Ørndrup; Bidoggia, Benoit; Maheshwari, Ram Krishan

2013-01-01

Particle accelerator magnet power supplies needs to be extremely precise. A new and innovative power supply for particle accelerator magnets is proposed. The topologies for the input and the output converter are shown and the control architecture is described.......Particle accelerator magnet power supplies needs to be extremely precise. A new and innovative power supply for particle accelerator magnets is proposed. The topologies for the input and the output converter are shown and the control architecture is described....

A Parallel Controls Software Approach for PEP II: AIDA and Matlab Middle Layer

International Nuclear Information System (INIS)

Wittmer, W.; Colocho, W.; White, G.

2007-01-01

The controls software in use at PEP II (Stanford Control Program - SCP) had originally been developed in the eighties. It is very successful in routine operation but due to its internal structure it is difficult and time consuming to extend its functionality. This is problematic during machine development and when solving operational issues. Routinely, data has to be exported from the system, analyzed offline, and calculated settings have to be reimported. Since this is a manual process, it is time consuming and error-prone. Setting up automated processes, as is done for MIA (Model Independent Analysis), is also time consuming and specific to each application. Recently, there has been a trend at light sources to use MATLAB as the platform to control accelerators using a 'MATLAB Middle Layer' (MML), and so called channel access (CA) programs to communicate with the low level control system (LLCS). This has proven very successful, especially during machine development time and trouble shooting. A special CA code, named AIDA (Accelerator Independent Data Access), was developed to handle the communication between MATLAB, modern software frameworks, and the SCP. The MML had to be adapted for implementation at PEP II. Colliders differ significantly in their designs compared to light sources, which poses a challenge. PEP II is the first collider at which this implementation is being done. We will report on this effort, which is still ongoing

Concurrent control system for the JAERI tandem accelerator

International Nuclear Information System (INIS)

Hanashima, S.; Shoji, T.; Horie, K.; Tsukihashi, Y.

1992-01-01

Concurrent processing with a multiprocessor system is introduced to the particle accelerator control system region. The control system is a good application in both logical and physical aspects. A renewal plan of the control system for the JAERI tandem accelerator is discussed. (author)

Discovery Mondays "Controlling the accelerators: tracking the protons"

CERN Multimedia

2007-01-01

Le Centre de contrôle des accélérateurs du CERN.Like a train of particles that picks up speed every time it passes a set of points, by the time they collide the protons and ions in the LHC will have followed their path through the six stages of the CERN accelerator complex, picking up speed at each stage. Operating the controls of this huge complex designed to accelerate the infinitesimally small are its peerless controllers. From the CERN Control Centre, they will be on duty day and night to accelerate the "wagon-loads" of particles, ensuring that they stay on track and lining them up for head-on collisions. At the next Discovery Monday you will discover the path taken by the particles through the accelerator chain. You will gain an insight into the complex work performed by those controlling the particles and learn more about the CERN accelerator complex and its Control Centre. Hop on board for a speed-of-light tour of the C...

Accelerator optimization using a network control and acquisition system

International Nuclear Information System (INIS)

Geddes, Cameron G.R.; Catravas, P.E.; Faure, Jerome; Toth, Csaba; Tilborg, J. van; Leemans, Wim P.

2002-01-01

Accelerator optimization requires detailed study of many parameters, indicating the need for remote control and automated data acquisition systems. A control and data acquisition system based on a network of commodity PCs and applications with standards based inter-application communication is being built for the l'OASIS accelerator facility. This system allows synchronous acquisition of data at high (> 1 Hz) rates and remote control of the accelerator at low cost, allowing detailed study of the acceleration process

Neural Networks for Modeling and Control of Particle Accelerators

Science.gov (United States)

Edelen, A. L.; Biedron, S. G.; Chase, B. E.; Edstrom, D.; Milton, S. V.; Stabile, P.

2016-04-01

Particle accelerators are host to myriad nonlinear and complex physical phenomena. They often involve a multitude of interacting systems, are subject to tight performance demands, and should be able to run for extended periods of time with minimal interruptions. Often times, traditional control techniques cannot fully meet these requirements. One promising avenue is to introduce machine learning and sophisticated control techniques inspired by artificial intelligence, particularly in light of recent theoretical and practical advances in these fields. Within machine learning and artificial intelligence, neural networks are particularly well-suited to modeling, control, and diagnostic analysis of complex, nonlinear, and time-varying systems, as well as systems with large parameter spaces. Consequently, the use of neural network-based modeling and control techniques could be of significant benefit to particle accelerators. For the same reasons, particle accelerators are also ideal test-beds for these techniques. Many early attempts to apply neural networks to particle accelerators yielded mixed results due to the relative immaturity of the technology for such tasks. The purpose of this paper is to re-introduce neural networks to the particle accelerator community and report on some work in neural network control that is being conducted as part of a dedicated collaboration between Fermilab and Colorado State University (CSU). We describe some of the challenges of particle accelerator control, highlight recent advances in neural network techniques, discuss some promising avenues for incorporating neural networks into particle accelerator control systems, and describe a neural network-based control system that is being developed for resonance control of an RF electron gun at the Fermilab Accelerator Science and Technology (FAST) facility, including initial experimental results from a benchmark controller.

A broadband accelerator control network

International Nuclear Information System (INIS)

Skelly, J.; Clifford, T.; Frankel, R.

1983-01-01

A broadband data communications network has been implemented at BNL for control of the Alternating Gradient Synchrotron (AGS) proton accelerator, using commercial CATV hardware, dual coaxial cables as the communications medium, and spanning 2.0 km. A 4 MHz bandwidth Digital Control Channel using CSMA-CA protocol is provided for digital data transmission, with 8 access nodes available over the length of the RELWAY. Each node consists of an rf modem and a microprocessor-based store-and-forward message handler which interfaces the RELWAY to a branch line implemented in GPIB. A gateway to the RELWAY control channel for the (preexisting) AGS Computerized Accelerator Operating System has been constructed using an LSI-11/23 microprocessor as a device in a GPIB branch line. A multilayer communications protocol has been defined for the Digital Control Channel, based on the ISO Open Systems Interconnect layered model, and a RELWAY Device Language defined as the required universal language for device control on this channel

A Comparison of Middle School Teachers' Pupil Control Ideology

Science.gov (United States)

Jones, Paul; Garner, Arthur E.

1978-01-01

Compares pupil control ideology--discipline policy--of middle school classroom teachers with the intent of finding what attributes are needed for middle school teachers and the particular type classroom environment that facilitates optimum learning conditions for middle school children. (Author/RK)

Computer applications: Automatic control system for high-voltage accelerator

International Nuclear Information System (INIS)

Bryukhanov, A.N.; Komissarov, P.Yu.; Lapin, V.V.; Latushkin, S.T.. Fomenko, D.E.; Yudin, L.I.

1992-01-01

An automatic control system for a high-voltage electrostatic accelerator with an accelerating potential of up to 500 kV is described. The electronic apparatus on the high-voltage platform is controlled and monitored by means of a fiber-optic data-exchange system. The system is based on CAMAC modules that are controlled by a microprocessor crate controller. Data on accelerator operation are represented and control instructions are issued by means of an alphanumeric terminal. 8 refs., 6 figs

Resonance control for a CW accelerator

International Nuclear Information System (INIS)

Young, L.M.; Biddle, R.S.

1987-01-01

This paper describes a resonance-control technique that has been successfully applied to several cw accelerating structures built by the Los Alamos National Laboratory for the National Bureau of Standards and for the University of Illinois. The technique involves sensing the rf fields in an accelerating structure as well as the rf power feeding into the cavity and, then, using the measurement to control the resonant frequency of the structure by altering the temperature of the structure. The temperature of the structure is altered by adjusting the temperature of the circulating cooling water. The technique has been applied to continuous wave (cw) side-coupled cavities only but should have applications with most high-average-power accelerator structures. Some additional effort would be required for pulsed systems

Workshop Engages PCs in Accelerator Controls

International Nuclear Information System (INIS)

Matthew Bickley

2006-01-01

To discuss the rapidly growing and changing use of personal computers (PCs) in accelerator control systems, 80 accelerator controls specialists from 26 institutions in North America, Europe and Asia attended the 6. International Workshop on Personal Computers and Particle Accelerator Controls, PCaPAC2006, held October 24-27 at Jefferson Lab in Newport News, Virginia. PCs have become increasingly applicable to the control of accelerators as their computing capacities have increased exponentially over the last 10 years. Capabilities that once required the power available only from expensive, small-market systems offered by DEC, Sun or IBM can now be obtained with commodity hardware offered by many vendors. The price/performance ratio presented by any standard PC makes a compelling case for using PC hardware in accelerator controls wherever possible. The PCaPAC meeting underscored the importance of collaborative control system development. Several talks focused on additions to three such systems, TINE, TANGO and EPICS. The diverse contributions to these toolkits, both in content and source, demonstrate the power of leveraged software development across a number of facilities. TINE originated in DESY's desire to give users a unified software bus above disparate underlying platforms. TINE discussions at PCaPAC centered on the toolkit's interface layers, including address redirection and integration with other control systems. TANGO has been a collaborative effort from its inception. Based on CORBA, this open-source controls toolkit is a registered project in the source forge system. The workshop TANGO presentation discussed contributions from four TANGO institutions, and mentioned a broad range of new tools, from user interface applications to code generators and database integration software. EPICS, which was started at LANL in the 1980s, includes contributions from dozens of institutions around the world. EPICS-related PCaPAC discussions included virtual machines at

Centralized digital control of accelerators

International Nuclear Information System (INIS)

Melen, R.E.

1983-09-01

In contrasting the title of this paper with a second paper to be presented at this conference entitled Distributed Digital Control of Accelerators, a potential reader might be led to believe that this paper will focus on systems whose computing intelligence is centered in one or more computers in a centralized location. Instead, this paper will describe the architectural evolution of SLAC's computer based accelerator control systems with respect to the distribution of their intelligence. However, the use of the word centralized in the title is appropriate because these systems are based on the use of centralized large and computationally powerful processors that are typically supported by networks of smaller distributed processors

Modern computer networks and distributed intelligence in accelerator controls

International Nuclear Information System (INIS)

Briegel, C.

1991-01-01

Appropriate hardware and software network protocols are surveyed for accelerator control environments. Accelerator controls network topologies are discussed with respect to the following criteria: vertical versus horizontal and distributed versus centralized. Decision-making considerations are provided for accelerator network architecture specification. Current trends and implementations at Fermilab are discussed

ORNL 25 MV tandem accelerator control system

International Nuclear Information System (INIS)

Juras, R.C.; Biggerstaff, J.A.; Hoglund, D.E.

1985-01-01

The CAMAC-based control system for the 25 MV tandem electrostatic accelerator of the Holifield Heavy Ion Research Facility at Oak Ridge National Laboratory (ORNL) was specified by ORNL and built by the National Electrostatics Corporation. Two Perkin-Elmer 32-bit minicomputers are used in the system, a message switching computer and a supervisory computer. The message switching computer transmits and receives control information on six serial highways. This computer shares memory with the supervisory computer. Operator consoles are located on a serial highway; control is by means of a console CRT, trackball, and assignable shaft encoders and meters. Two identical consoles operate simultaneously: one is located in the tandem control room; the other is located in the cyclotron control room to facilitate operation during injection of tandem beams into the cyclotron or when beam lines under control of the cyclotron control system are used. The supervisory computer is used for accelerator parameter setup calculations, actual accelerator setup for new beams based on scaled, recorded parameters from previously run beams, and various other functions. Nearly seven years of control system operation and improvements will be discussed

Model-based accelerator controls: What, why and how

International Nuclear Information System (INIS)

Sidhu, S.S.

1987-01-01

Model-based control is defined as a gamut of techniques whose aim is to improve the reliability of an accelerator and enhance the capabilities of the operator, and therefore of the whole control system. The aim of model-based control is seen as gradually moving the function of model-reference from the operator to the computer. The role of the operator in accelerator control and the need for and application of model-based control are briefly summarized

Measurements and simulation of controlled beamfront motion in the Laser Controlled Collective Accelerator

International Nuclear Information System (INIS)

Yao, R.L.; Destler, W.W.; Striffler, C.D.; Rodgers, J.; Scgalov, Z.

1989-01-01

In the Laser Controlled Collective Accelerator, an intense electron beam is injected at a current above the vacuum space charge limit into an initially evacuated drift tube. A plasma channel, produced by time-sequenced, multiple laser beam ionization of a solid target on the drift tube wall, provides the necessary neutralization to allow for effective beam propagation. By controlling the rate of production of the plasma channel as a function of time down the drift tube, control of the electron beamfront can be achieved. Recent experimental measurements of controlled beamfront motion in this configuration are presented, along with results of ion acceleration experiments conducted using two different accelerating gradients. These results are compared with numerical simulations of the system in which both controlled beamfront motion and ion acceleration is observed consistent with both design expectations and experimental results. 5 refs., 6 figs

Generic device controller for accelerator control systems

International Nuclear Information System (INIS)

Mariotti, R.; Buxton, W.; Frankel, R.; Hoff, L.

1987-01-01

Distributed intelligence for accelerator control systems has become possible as a result of advances in microprocessor technology. A system based on distributed intelligence is inherently versatile, readily expandable, and reduces both information flow across the system and software complexity in each unit

Computer Based Dose Control System on Linear Accelerator

International Nuclear Information System (INIS)

Taxwim; Djoko-SP; Widi-Setiawan; Agus-Budi Wiyatna

2000-01-01

The accelerator technology has been used for radio therapy. DokterKaryadi Hospital in Semarang use electron or X-ray linear accelerator (Linac)for cancer therapy. One of the control parameter of linear accelerator isdose rate. It is particle current or amount of photon rate to the target. Thecontrol of dose rate in linac have been done by adjusting repetition rate ofanode pulse train of electron source. Presently the control is stillproportional control. To enhance the quality of the control result (minimalstationer error, velocity and stability), the dose control system has beendesigned by using the PID (Proportional Integral Differential) controlalgorithm and the derivation of transfer function of control object.Implementation of PID algorithm control system is done by giving an input ofdose error (the different between output dose and dose rate set point). Theoutput of control system is used for correction of repetition rate set pointfrom pulse train of electron source anode. (author)

40 CFR 81.120 - Middle Tennessee Intrastate Air Quality Control Region.

Science.gov (United States)

2010-07-01

... Quality Control Region. 81.120 Section 81.120 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Air Quality Control Regions § 81.120 Middle Tennessee Intrastate Air Quality Control Region. The Middle Tennessee Intrastate Air Quality Control Region consists of the territorial area encompassed by...

High-performance control system for a heavy-ion medical accelerator

Energy Technology Data Exchange (ETDEWEB)

Lancaster, H.D.; Magyary, S.B.; Sah, R.C.

1983-03-01

A high performance control system is being designed as part of a heavy ion medical accelerator. The accelerator will be a synchrotron dedicated to clinical and other biomedical uses of heavy ions, and it will deliver fully stripped ions at energies up to 800 MeV/nucleon. A key element in the design of an accelerator which will operate in a hospital environment is to provide a high performance control system. This control system will provide accelerator modeling to facilitate changes in operating mode, provide automatic beam tuning to simplify accelerator operations, and provide diagnostics to enhance reliability. The control system being designed utilizes many microcomputers operating in parallel to collect and transmit data; complex numerical computations are performed by a powerful minicomputer. In order to provide the maximum operational flexibility, the Medical Accelerator control system will be capable of dealing with pulse-to-pulse changes in beam energy and ion species.

High-performance control system for a heavy-ion medical accelerator

International Nuclear Information System (INIS)

Lancaster, H.D.; Magyary, S.B.; Sah, R.C.

1983-03-01

A high performance control system is being designed as part of a heavy ion medical accelerator. The accelerator will be a synchrotron dedicated to clinical and other biomedical uses of heavy ions, and it will deliver fully stripped ions at energies up to 800 MeV/nucleon. A key element in the design of an accelerator which will operate in a hospital environment is to provide a high performance control system. This control system will provide accelerator modeling to facilitate changes in operating mode, provide automatic beam tuning to simplify accelerator operations, and provide diagnostics to enhance reliability. The control system being designed utilizes many microcomputers operating in parallel to collect and transmit data; complex numerical computations are performed by a powerful minicomputer. In order to provide the maximum operational flexibility, the Medical Accelerator control system will be capable of dealing with pulse-to-pulse changes in beam energy and ion species

The NSC 16 MV tandem accelerator control system

International Nuclear Information System (INIS)

Ajith Kumar, B.P.; Kannaiyan, J.; Sugathan, P.; Bhowmik, R.K.

1994-01-01

The computerized control system for the 16 MV Pelletron accelerator at the Nuclear Science Centre runs on a PC-AT 386 computer. Devices in the accelerator are interfaced to the computer by using a CAMAC Serial Highway. The software, written in C, is Database oriented and supports many features useful for the accelerator operation. The control console consists of an EGA monitor, keyboard, assignable control knobs and meters, a diagrammatic display showing the overall status of the machine and a similar panel for showing the status of radiation safety interlocks. The system has been operational for the past three years and is discussed below. (orig.)

Experimental studies of the laser-controlled collective ion accelerator

International Nuclear Information System (INIS)

Destler, W.W.; Rodgers, J.; Segalov, Z.

1989-01-01

Detailed experimental studies of a collective acceleration experiment in which a time-sequenced laser-generated ionization channel is used to control the propagation of an intense relativistic electron beamfront are presented. Ions trapped in the potential well at the beamfront are accelerated as the velocity of the beamfront is increased in a manner controlled by the time-dependent axial extent of the ionization channel. Beamfront propagation data for two different accelerating gradients are presented, together with results of ion acceleration studies for both gradients

Design of digital logic control for accelerator magnet power supply

International Nuclear Information System (INIS)

Long Fengli; Hu Wei; Cheng Jian

2008-01-01

For the accelerator magnet power supply, usually the Programmable Logic Controller (PLC) is used to server as the controller for logic protection and control. Along with the development of modern accelerator technology, it is a trend to use fully-digital control to the magnet power supply. It is possible to integrate the logic control part into the digital control component of the power supply, for example, the Field Programmable Gate Array (FPGA). The paper introduces to different methods which are designed for the logic protection and control for accelerator magnet power supplies with the FPGA as the control component. (authors)

Common control system for the CERN accelerators

International Nuclear Information System (INIS)

Rausch, R.; Serre, Ch.

1992-01-01

The PS and SPS Accelerator Control Systems are becoming obsolete and need urgent rejuvenation. After a control users forum, where users expressed their needs, two main Working Groups were set up, consisting of Control and Equipment Specialists and experienced Machine Operators. One Working Group studied the architecture and the front-end processing and the other a common approach to the application software needed to run the CERN accelerator complex. The paper presents the technical conclusion of their work and the policy to implement it, taking into account the necessity to operate both machines without interruption of the Physics Program. (author)

Software for virtual accelerator designing

International Nuclear Information System (INIS)

Kulabukhova, N.; Ivanov, A.; Korkhov, V.; Lazarev, A.

2012-01-01

The article discusses appropriate technologies for software implementation of the Virtual Accelerator. The Virtual Accelerator is considered as a set of services and tools enabling transparent execution of computational software for modeling beam dynamics in accelerators on distributed computing resources. Distributed storage and information processing facilities utilized by the Virtual Accelerator make use of the Service-Oriented Architecture (SOA) according to a cloud computing paradigm. Control system tool-kits (such as EPICS, TANGO), computing modules (including high-performance computing), realization of the GUI with existing frameworks and visualization of the data are discussed in the paper. The presented research consists of software analysis for realization of interaction between all levels of the Virtual Accelerator and some samples of middle-ware implementation. A set of the servers and clusters at St.-Petersburg State University form the infrastructure of the computing environment for Virtual Accelerator design. Usage of component-oriented technology for realization of Virtual Accelerator levels interaction is proposed. The article concludes with an overview and substantiation of a choice of technologies that will be used for design and implementation of the Virtual Accelerator. (authors)

Application accelerator system having bunch control

Science.gov (United States)

Wang, Dunxiong; Krafft, Geoffrey Arthur

1999-01-01

An application accelerator system for monitoring the gain of a free electron laser. Coherent Synchrotron Radiation (CSR) detection techniques are used with a bunch length monitor for ultra short, picosec to several tens of femtosec, electron bunches. The monitor employs an application accelerator, a coherent radiation production device, an optical or beam chopping device, an infrared radiation collection device, a narrow-banding filter, an infrared detection device, and a control.

Low-level RF control system issues for an ADTT accelerator

International Nuclear Information System (INIS)

Ziomek, C.D.; Regan, A.H.; Lynch, M.T.; Bowling, P.S.

1994-01-01

The RF control system for a charged-particle accelerator must maintain the correct amplitude and phase of RF field inside the accelerator cavity in the presence of perturbations, noises, and time varying system components. For an accelerator with heavy beam-loading, fluctuations in the beam current cause large perturbations to the RF field amplitude and phase that must be corrected by the RF control system. The ADTT applications require a high-current, heavily beam-loaded, continuous-wave (CW) accelerator. Additional concerns created by the CW operation include system start-up, beam interruption, and fault recovery. Also, the RF control system for an ADTT facility must include sophisticated automation to reduce the operator interaction and support. This paper describes an RF control system design that addresses these various issues by evaluation a combination of feedback and feed forward control techniques. Experience from the high-current Ground Test Accelerator (GTA) is drawn upon for this RF control system design. Comprehensive computer modeling with the Matrix x software has been used to predict the performance of this RF control system

Collective ion acceleration via laser controlled ionization channel

International Nuclear Information System (INIS)

Destler, W.W.; O'Shea, P.G.; Rodgers, J.; Segalov, Z.

1987-01-01

Initial results from a successful laser-controlled collective ion acceleration experiment at the University of Maryland are presented. In the experiment, positive ions are trapped in the potential well at the head of an intense relativistic electron beam injected at current levels above the space charge limit. Seed ions for acceleration are provided by puff valve injection of a neutral gas cloud localized to within 3 cm of the injection point. Control over the acceleration of the well and the ions is then achieved by means of a laser-generated ionization channel produced by passing the light from a Q-switched ruby laser through a series of partially and fully reflecting mirrors in such a way as to provide time-sequenced laser ionization of a target located on the drift tube wall. Using this system, controlled acceleration of protons at a rate of approximately 40 MV/m has been demonstrated over a distance of about 50 cm

IKONET: distributed accelerator and experiment control

International Nuclear Information System (INIS)

Koldewijn, P.

1986-01-01

IKONET is a network consisting of some 35 computers used to control the 500 MeV Medium Energy Amsterdam electron accelerator (MEA) and its various experiments. The control system is distributed over a whole variety of machines, which are combined in a transparent central-oriented network. The local hardware is switched and tuned via Camac by a series of mini-computers with a real-time multitask operating system. Larger systems provide central intelligence for the higher-level control layers. An image of the complete accelerator settings is maintained by central database administrators. Different operator facilities handle touchpanels, multi-purpose knobs and graphical displays. The network provides remote login facilities and file servers. On basis of the present layout, an overview is given of future developments for subsystems of the network. (Auth.)

Application accelerator system having bunch control

International Nuclear Information System (INIS)

Wang, D.; Krafft, G.A.

1999-01-01

An application accelerator system for monitoring the gain of a free electron laser is disclosed. Coherent Synchrotron Radiation (CSR) detection techniques are used with a bunch length monitor for ultra short, picosec to several tens of femtosec, electron bunches. The monitor employs an application accelerator, a coherent radiation production device, an optical or beam chopping device, an infrared radiation collection device, a narrow-banding filter, an infrared detection device, and a control. 1 fig

Control Infrastructure for a Pulsed Ion Accelerator

International Nuclear Information System (INIS)

Persaud, A.; Regis, M. J.; Stettler, M. W.; Vytla, V. K.

2016-01-01

We report on updates to the accelerator controls for the Neutralized Drift Compression Experiment II, a pulsed induction-type accelerator for heavy ions. The control infrastructure is built around a LabVIEW interface combined with an Apache Cassandra backend for data archiving. Recent upgrades added the storing and retrieving of device settings into the database, as well as ZeroMQ as a message broker that replaces LabVIEW's shared variables. Converting to ZeroMQ also allows easy access via other programming languages, such as Python.

Control Infrastructure for a Pulsed Ion Accelerator

Science.gov (United States)

Persaud, A.; Regis, M. J.; Stettler, M. W.; Vytla, V. K.

2016-10-01

We report on updates to the accelerator controls for the Neutralized Drift Compression Experiment II, a pulsed induction-type accelerator for heavy ions. The control infrastructure is built around a LabVIEW interface combined with an Apache Cassandra backend for data archiving. Recent upgrades added the storing and retrieving of device settings into the database, as well as ZeroMQ as a message broker that replaces LabVIEW's shared variables. Converting to ZeroMQ also allows easy access via other programming languages, such as Python.

Adaptive control for accelerators

International Nuclear Information System (INIS)

Eaton, L.E.; Jachim, S.P.; Natter, E.F.

1991-01-01

This patent describes an adaptive feedforward control loop is provided to stabilize accelerator beam loading of the radio frequency field in an accelerator cavity during successive pulses of the beam into the cavity. A digital signal processor enables an adaptive algorithm to generate a feedforward error correcting signal functionally determined by the feedback error obtained by a beam pulse loading the cavity after the previous correcting signal was applied to the cavity. Each cavity feedforward correcting signal is successively stored in the digital processor and modified by the feedback error resulting from its application to generate the next feedforward error correcting signal. A feedforward error correcting signal is generated by the digital processor in advance of the beam pulse to enable a composite correcting signal and the beam pulse to arrive concurrently at the cavity

Adaptive control for accelerators

Science.gov (United States)

Eaton, Lawrie E.; Jachim, Stephen P.; Natter, Eckard F.

1991-01-01

An adaptive feedforward control loop is provided to stabilize accelerator beam loading of the radio frequency field in an accelerator cavity during successive pulses of the beam into the cavity. A digital signal processor enables an adaptive algorithm to generate a feedforward error correcting signal functionally determined by the feedback error obtained by a beam pulse loading the cavity after the previous correcting signal was applied to the cavity. Each cavity feedforward correcting signal is successively stored in the digital processor and modified by the feedback error resulting from its application to generate the next feedforward error correcting signal. A feedforward error correcting signal is generated by the digital processor in advance of the beam pulse to enable a composite correcting signal and the beam pulse to arrive concurrently at the cavity.

Fermilab accelerator control system: Analog monitoring facilities

International Nuclear Information System (INIS)

Seino, K.; Anderson, L.; Smedinghoff, J.

1987-10-01

Thousands of analog signals are monitored in different areas of the Fermilab accelerator complex. For general purposes, analog signals are sent over coaxial or twinaxial cables with varying lengths, collected at fan-in boxes and digitized with 12 bit multiplexed ADCs. For higher resolution requirements, analog signals are digitized at sources and are serially sent to the control system. This paper surveys ADC subsystems that are used with the accelerator control systems and discusses practical problems and solutions, and it describes how analog data are presented on the console system

The computer-based control system of the NAC accelerator

International Nuclear Information System (INIS)

Burdzik, G.F.; Bouckaert, R.F.A.; Cloete, I.; Du Toit, J.S.; Kohler, I.H.; Truter, J.N.J.; Visser, K.

1982-01-01

The National Accelerator Centre (NAC) of the CSIR is building a two-stage accelerator which will provide charged-particle beams for the use in medical and research applications. The control system for this accelerator is based on three mini-computers and a CAMAC interfacing network. Closed-loop control is being relegated to the various subsystems of the accelerators, and the computers and CAMAC network will be used in the first instance for data transfer, monitoring and servicing of the control consoles. The processing power of the computers will be utilized for automating start-up and beam-change procedures, for providing flexible and convenient information at the control consoles, for fault diagnosis and for beam-optimizing procedures. Tasks of a localized or dedicated nature are being off-loaded onto microcomputers, which are being used either in front-end devices or as slaves to the mini-computers. On the control consoles only a few instruments for setting and monitoring variables are being provided, but these instruments are universally-linkable to any appropriate machine variable

Accelerator controls at CERN: Some converging trends

International Nuclear Information System (INIS)

Kuiper, B.

1990-01-01

CERN's growing services to the high-energy physics community using frozen resources has led to the implementation of 'Technical Boards', mandated to assist the management by making recommendations for rationalizations in various technological domains. The Board on Process Control and Electronics for Accelerators, TEBOCO, has emphasized four main lines which might yield economy in resources. First, a common architecture for accelerator controls has been agreed between the three accelerator divisions. Second, a common hardware/software kit has been defined, from which the large majority of future process interfacing may be composed. A support service for this kit is an essential part of the plan. Third, high-level protocols have been developed for standardizing access to process devices. They derive from agreed standard models of the devices and involve a standard control message. This should ease application development and mobility of equipment. Fourth, a common software engineering methodology and a commercial package of application development tools have been adopted. Some rationalization in the field of the man-machine interface and in matters of synchronization is also under way. (orig.)

Accelerator controls at CERN: Some converging trends

Science.gov (United States)

Kuiper, B.

1990-08-01

CERN's growing services to the high-energy physics community using frozen resources has led to the implementation of "Technical Boards", mandated to assist the management by making recommendations for rationalizations in various technological domains. The Board on Process Control and Electronics for Accelerators, TEBOCO, has emphasized four main lines which might yield economy in resources. First, a common architecture for accelerator controls has been agreed between the three accelerator divisions. Second, a common hardware/software kit has been defined, from which the large majority of future process interfacing may be composed. A support service for this kit is an essential part of the plan. Third, high-level protocols have been developed for standardizing access to process devices. They derive from agreed standard models of the devices and involve a standard control message. This should ease application development and mobility of equipment. Fourth, a common software engineering methodology and a commercial package of application development tools have been adopted. Some rationalization in the field of the man-machine interface and in matters of synchronization is also under way.

Accelerator and feedback control simulation using neural networks

International Nuclear Information System (INIS)

Nguyen, D.; Lee, M.; Sass, R.; Shoaee, H.

1991-05-01

Unlike present constant model feedback system, neural networks can adapt as the dynamics of the process changes with time. Using a process model, the ''Accelerator'' network is first trained to simulate the dynamics of the beam for a given beam line. This ''Accelerator'' network is then used to train a second ''Controller'' network which performs the control function. In simulation, the networks are used to adjust corrector magnetics to control the launch angle and position of the beam to keep it on the desired trajectory when the incoming beam is perturbed. 4 refs., 3 figs

Development of a distributed control system for the JAERI tandem accelerator facility

International Nuclear Information System (INIS)

Hanashima, Susumu

2005-01-01

In the JAERI tandem accelerator facility, we are building accelerator complex aiming generation and acceleration of radio nuclear beam. Several accelerators, ion sources and a charge breeder are installed in the facility. We are developing a distributed control system enabling smooth operation of the facility. We report basic concepts of the control system in this article. We also describe about a control hardware using plastic optical fiber, which is developed for the control system. (author)

Towards MRI-guided linear accelerator control: gating on an MRI accelerator.

Science.gov (United States)

Crijns, S P M; Kok, J G M; Lagendijk, J J W; Raaymakers, B W

2011-08-07

To boost the possibilities of image guidance in radiotherapy by providing images with superior soft-tissue contrast during treatment, we pursue diagnostic quality MRI functionality integrated with a linear accelerator. Large respiration-induced semi-periodic target excursions hamper treatment of cancer of the abdominal organs. Methods to compensate in real time for such motion are gating and tracking. These strategies are most effective in cases where anatomic motion can be visualized directly, which supports the use of an integrated MRI accelerator. We establish here an infrastructure needed to realize gated radiation delivery based on MR feedback and demonstrate its potential as a first step towards more advanced image guidance techniques. The position of a phantom subjected to one-dimensional periodic translation is tracked with the MR scanner. Real-time communication with the MR scanner and control of the radiation beam are established. Based on the time-resolved position of the phantom, gated radiation delivery to the phantom is realized. Dose distributions for dynamic delivery conditions with varying gating windows are recorded on gafchromic film. The similarity between dynamically and statically obtained dose profiles gradually increases as the gating window is decreased. With gating windows of 5 mm, we obtain sharp dose profiles. We validate our gating implementation by comparing measured dose profiles to theoretical profiles calculated using the knowledge of the imposed motion pattern. Excellent correspondence is observed. At the same time, we show that real-time on-line reconstruction of the accumulated dose can be performed using time-resolved target position information. This facilitates plan adaptation not only on a fraction-to-fraction scale but also during one fraction, which is especially valuable in highly accelerated treatment strategies. With the currently established framework and upcoming improvements to our prototype-integrated MRI accelerator

Accelerator Control and Global Networks State of the Art

CERN Document Server

Gurd, D P

2004-01-01

As accelerators increase in size and complexity, demands upon their control systems increase correspondingly. Machine complexity is reflected in complexity of control system hardware and software and careful configuration management is essential. Model-based procedures and fast feedback based upon even faster beam instrumentation are often required. Managing machine protection systems with tens of thousands of inputs is another significant challenge. Increased use of commodity hardware and software introduces new issues of security and control. Large new facilities will increasingly be built by national (e.g. SNS) or international (e.g. a linear collider) collaborations. Building an integrated control system for an accelerator whose development is geographically widespread presents particular problems, not all of them technical. Recent discussions of a “Global Accelerator Network” include the possibility of multiple remote control rooms and no more night shifts. Based upon current experien...

Kinematics and Dynamics of Motion Control Based on Acceleration Control

Science.gov (United States)

Ohishi, Kiyoshi; Ohba, Yuzuru; Katsura, Seiichiro

The first IEEE International Workshop on Advanced Motion Control was held in 1990 pointed out the importance of physical interpretation of motion control. The software servoing technology is now common in machine tools, robotics, and mechatronics. It has been intensively developed for the numerical control (NC) machines. Recently, motion control in unknown environment will be more and more important. Conventional motion control is not always suitable due to the lack of adaptive capability to the environment. A more sophisticated ability in motion control is necessary for compliant contact with environment. Acceleration control is the key technology of motion control in unknown environment. The acceleration control can make a motion system to be a zero control stiffness system without losing the robustness. Furthermore, a realization of multi-degree-of-freedom motion is necessary for future human assistance. A human assistant motion will require various control stiffness corresponding to the task. The review paper focuses on the modal coordinate system to integrate the various control stiffness in the virtual axes. A bilateral teleoperation is a good candidate to consider the future human assistant motion and integration of decentralized systems. Thus the paper reviews and discusses the bilateral teleoperation from the control stiffness and the modal control design points of view.

Automatic frequency control system for driving a linear accelerator

International Nuclear Information System (INIS)

Helgesson, A.L.

1976-01-01

An automatic frequency control system is described for maintaining the drive frequency applied to a linear accelerator to produce maximum particle output from the accelerator. The particle output amplitude is measured and the frequency of the radio frequency source powering the linear accelerator is adjusted to maximize particle output amplitude

Controller for control of pulsed electron linear accelerator

International Nuclear Information System (INIS)

Bryazgin, A.A.; Faktorovich, B.L.

1995-01-01

The controller is based on the K1816VE31 microprocessor and contains 22-channel integrating 10-digital two-wire analog-to-digital converter, 8-channel 12-digit digital-to-analog converter, 24-digit output register, 16-digit input register pulse generator in the range of 0.5 - 50 Hz with the regulation step of 0.05 Hz and delayed pulse generator. The controller is used for pulsed electron linear accelerator control and is reduced to regulation of the electron beam pulse repetition rate and beam energy. 1 ref., 1 fig

Microprocessor controller for phasing the accelerator

International Nuclear Information System (INIS)

Howry, S.K.; Wilmunder, A.R.

1977-03-01

A microprocessor controller is being developed to perform automatic phasing of the SLAC accelerator. It will replace the existing relay/analog boxes which are ten years old. The new system is all solid state except for the stepping motors that drive the phase shifters. A description is given of the components of the system, the control algorithm, microprocessor hardware and software design and development, and interaction with SLAC's computer control system

Evolution of control systems for accelerators

International Nuclear Information System (INIS)

Crowley-Milling, M.C.

1983-01-01

The author reviews the development of control systems for accelerators. After an historical survey and a general introduction the hardware and software of such systems is described. As example the control system of the CERN SP5 is considered. Finally an outlook is given to future developments with special regards to the LEP storage ring. (HSI)

The BNL Accelerator Test Facility control system

International Nuclear Information System (INIS)

Malone, R.; Bottke, I.; Fernow, R.; Ben-Zvi, I.

1993-01-01

Described is the VAX/CAMAC-based control system for Brookhaven National Laboratory's Accelerator Test Facility, a laser/linac research complex. Details of hardware and software configurations are presented along with experiences of using Vsystem, a commercial control system package

Database application research in real-time data access of accelerator control system

International Nuclear Information System (INIS)

Chen Guanghua; Chen Jianfeng; Wan Tianmin

2012-01-01

The control system of Shanghai Synchrotron Radiation Facility (SSRF) is a large-scale distributed real-time control system, It involves many types and large amounts of real-time data access during the operating. Database system has wide application prospects in the large-scale accelerator control system. It is the future development direction of the accelerator control system, to replace the differently dedicated data structures with the mature standardized database system. This article discusses the application feasibility of database system in accelerators based on the database interface technology, real-time data access testing, and system optimization research and to establish the foundation of the wide scale application of database system in the SSRF accelerator control system. Based on the database interface technology, real-time data access testing and system optimization research, this article will introduce the application feasibility of database system in accelerators, and lay the foundation of database system application in the SSRF accelerator control system. (authors)

General man-machine interface used in accelerators controls

International Nuclear Information System (INIS)

Boutheon, M.; Di Maio, F.; Pace, A.

1992-01-01

A large community is now using Workstations as Accelerators Computer Controls Interface, through the concepts of windows - menus - synoptics - icons. Some standards were established for the CERN-PS control systems rejuvenation. The Booster-to-PS transfer and injection process is now entirely operated with these tools. This application constitutes a global environment providing the users with the controls, analysis, visualization of a part of an accelerator. Individual commands, measurements, and specialized programs including complex treatments are available in a homogeneous frame. Some months of experience in current operation have shown that this model can be extended to the whole project. (author)

Resonance control for a cw [continuous wave] accelerator

International Nuclear Information System (INIS)

Young, L.M.; Biddle, R.S.

1987-01-01

A resonance-control technique is described that has been successfully applied to several cw accelerating structures built by the Los Alamos National Laboratory for the National Bureau of Standards and for the University of Illinois. The technique involves sensing the rf fields in an accelerating structure as well as the rf power feeding into the cavity and, then, using the measurement to control the resonant frequency of the structure by altering the temperature of the structure. The temperature of the structure is altered by adjusting the temperature of the circulating cooling water. The technique has been applied to continuous wave (cw) side-coupled cavities only but should have applications with most high-average-power accelerator structures. Some additional effort would be required for pulsed systems

Object oriented programming interfaces for accelerator control

International Nuclear Information System (INIS)

Hoff, L.T.

1997-01-01

Several years ago, the AGS controls group was given the task of developing software for the RHIC accelerator. Like the AGS, the RHIC control system needs to control and monitor equipment distributed around a relatively large geographic area. A local area network connects this equipment to a collection of UNIX workstations in a central control room. Similar software had been developed for the AGS about a decade earlier, but isn't well suited for RHIC use for a number of reasons. Rather than adapt the AGS software for RHIC use, the controls group opted to start with a clean slate. To develop software that would address the shortcomings of the AGS software, while preserving the useful features that evolved through years of use. A current trend in control system design is to provide an object oriented programming interface for application developers. This talk will discuss important aspects and features of object oriented application programming interfaces (APIs) for accelerator control systems, and explore why such interfaces are becoming the norm

Automatic control variac system for electronic accelerator

International Nuclear Information System (INIS)

Zhang Shuocheng; Wang Dan; Jing Lan; Qiao Weimin; Ma Yunhai

2006-01-01

An automatic control variac system is designed in order to satisfy the controlling requirement of the electronic accelerator developed by the Institute. Both design and operational principles, structure of the system as well as the software of industrial PC and micro controller unit are described. The interfaces of the control module are RS232 and RS485. A fiber optical interface (FOC) could be set up if an industrial FOC network is necessary, which will extend the filed of its application and make the communication of the system better. It is shown in practice that the system can adjust the variac output voltage automatically and assure the accurate and automatic control of the electronic accelerator. The system is designed in accordance with the general design principles and possesses the merits such as easy operation and maintenance, good expansibility, and low cost, thus it could also be used in other industrial branches. (authors)

Techniques for increasing the reliability of accelerator control system electronics

International Nuclear Information System (INIS)

Utterback, J.

1993-09-01

As the physical size of modern accelerators becomes larger and larger, the number of required control system circuit boards increases, and the probability of one of those circuit boards failing while in service also increases. In order to do physics, the experimenters need the accelerator to provide beam reliably with as little down time as possible. With the advent of colliding beams physics, reliability becomes even more important due to the fact that a control system failure can cause the loss of painstakingly produced antiprotons. These facts prove the importance of keeping reliability in mind when designing and maintaining accelerator control system electronics

Requirements and solutions for accelerator control systems

International Nuclear Information System (INIS)

Anicic, D.; Blumer, T.; Jirousek, I.; Lutz, H.; Mezger, A.

2001-01-01

Throughout the life cycle of control systems, we are faced with the question of what fabulous new piece of hardware or software should be used and how to integrate this into a viable system. Accelerators cover a wide range, from simple cyclotrons for isotope production, to cascades of cyclotrons for variable energy and multiple particles, this precludes a standard answer for all cases. The system requirements according to the purpose and nature of the accelerator are analyzed and we try to extract some guidelines for implementation, development and maintenance of the appropriate control systems. We then try to analyze present trends in a selection of fields like operating systems, commercial systems, software sharing, field busses, etc

77 FR 22637 - Federal Motor Vehicle Safety Standards; Accelerator Control Systems

Science.gov (United States)

2012-04-16

... revise the Federal Motor Vehicle Safety Standard for accelerator control systems (ACS) in two ways. First... Standard (FMVSS) No. 124, Accelerator Control Systems,\\2\\ in two ways. First, we are proposing to update... February 2011 final report ``Technical Assessment of Toyota Electronic Throttle Control Systems,'' the...

Model-based Acceleration Control of Turbofan Engines with a Hammerstein-Wiener Representation

Science.gov (United States)

Wang, Jiqiang; Ye, Zhifeng; Hu, Zhongzhi; Wu, Xin; Dimirovsky, Georgi; Yue, Hong

2017-05-01

Acceleration control of turbofan engines is conventionally designed through either schedule-based or acceleration-based approach. With the widespread acceptance of model-based design in aviation industry, it becomes necessary to investigate the issues associated with model-based design for acceleration control. In this paper, the challenges for implementing model-based acceleration control are explained; a novel Hammerstein-Wiener representation of engine models is introduced; based on the Hammerstein-Wiener model, a nonlinear generalized minimum variance type of optimal control law is derived; the feature of the proposed approach is that it does not require the inversion operation that usually upsets those nonlinear control techniques. The effectiveness of the proposed control design method is validated through a detailed numerical study.

A high performance architecture for accelerator controls

International Nuclear Information System (INIS)

Allen, M.; Hunt, S.M; Lue, H.; Saltmarsh, C.G.; Parker, C.R.C.B.

1991-01-01

The demands placed on the Superconducting Super Collider (SSC) control system due to large distances, high bandwidth and fast response time required for operation will require a fresh approach to the data communications architecture of the accelerator. The prototype design effort aims at providing deterministic communication across the accelerator complex with a response time of < 100 ms and total bandwidth of 2 Gbits/sec. It will offer a consistent interface for a large number of equipment types, from vacuum pumps to beam position monitors, providing appropriate communications performance for each equipment type. It will consist of highly parallel links to all equipment: those with computing resources, non-intelligent direct control interfaces, and data concentrators. This system will give each piece of equipment a dedicated link of fixed bandwidth to the control system. Application programs will have access to all accelerator devices which will be memory mapped into a global virtual addressing scheme. Links to devices in the same geographical area will be multiplexed using commercial Time Division Multiplexing equipment. Low-level access will use reflective memory techniques, eliminating processing overhead and complexity of traditional data communication protocols. The use of commercial standards and equipment will enable a high performance system to be built at low cost

A high performance architecture for accelerator controls

International Nuclear Information System (INIS)

Allen, M.; Hunt, S.M.; Lue, H.; Saltmarsh, C.G.; Parker, C.R.C.B.

1991-03-01

The demands placed on the Superconducting Super Collider (SSC) control system due to large distances, high bandwidth and fast response time required for operation will require a fresh approach to the data communications architecture of the accelerator. The prototype design effort aims at providing deterministic communication across the accelerator complex with a response time of <100 ms and total bandwidth of 2 Gbits/sec. It will offer a consistent interface for a large number of equipment types, from vacuum pumps to beam position monitors, providing appropriate communications performance for each equipment type. It will consist of highly parallel links to all equipments: those with computing resources, non-intelligent direct control interfaces, and data concentrators. This system will give each piece of equipment a dedicated link of fixed bandwidth to the control system. Application programs will have access to all accelerator devices which will be memory mapped into a global virtual addressing scheme. Links to devices in the same geographical area will be multiplexed using commercial Time Division Multiplexing equipment. Low-level access will use reflective memory techniques, eliminating processing overhead and complexity of traditional data communication protocols. The use of commercial standards and equipment will enable a high performance system to be built at low cost. 1 fig

Hacking control systems, switching… accelerators off?

CERN Multimedia

Computer Security Team

2013-01-01

In response to our article in the last Bulletin, we received the following comment: “Wasn’t Stuxnet designed to stop the Iranian nuclear programme? Why then all this noise with regard to CERN accelerators? Don’t you realize that ‘computer security’ is not the raison d'être of CERN?”. Thank you for this golden opportunity to delve into this issue.   Given the sophistication of Stuxnet, it might have been hard to detect such a targeted attack against CERN, if at all. But this is not the point. There are much simpler risks for our accelerator complex and infrastructure. And, while “‘computer security’ is [indeed] not the raison d' être”, it is our collective responsibility to keep this risk at bay.   Examples? Just think of a simple computer virus infecting Windows-based control PCs connected to the accelerator network (the Technical Network, &ld...

Accelerator control using RSX-11M and CAMAC

International Nuclear Information System (INIS)

Kulaga, J.E.

1978-01-01

This paper describes a computer-control system for a superconducting linear accelerator currently under development at Argonne National Laboratory. RSX-11M V3.1 running on a PDP 11/34 is used with CAMAC hardware to fully control 22 active beam-line elements and monitor critical accelerator conditions such as temperature, vacuum, and beam characteristics. This paper contrasts the use of an RSX compatible CAMAC driver for most CAMAC I/O operations and the use of the Connect-to-Interrupt Vector directive for fast ADC operation. The usage of table-driven software to achieve hardware configuration independence is discussed, along with the design considerations of the software interface between a human operator and a computer-control system featuring multi-function computer-readable control knobs and computer-writable displays which make up the operator's control console

Quick setup of test unit for accelerator control system

International Nuclear Information System (INIS)

Fu, W.; D'Ottavio, T.; Gassner, D.; Nemesure, S.; Morris, J.

2011-01-01

Testing a single hardware unit of an accelerator control system often requires the setup of a program with graphical user interface. Developing a dedicated application for a specific hardware unit test could be time consuming and the application may become obsolete after the unit tests. This paper documents a methodology for quick design and setup of an interface focused on performing unit tests of accelerator equipment with minimum programming work. The method has three components. The first is a generic accelerator device object (ADO) manager which can be used to setup, store, and log testing controls parameters for any unit testing system. The second involves the design of a TAPE (Tool for Automated Procedure Execution) sequence file that specifies and implements all te testing and control logic. The sting third is the design of a PET (parameter editing tool) page that provides the unit tester with all the necessary control parameters required for testing. This approach has been used for testing the horizontal plane of the Stochastic Cooling Motion Control System at RHIC.

Neuromuscular Control of Rapid Linear Accelerations in Fish

Science.gov (United States)

2016-06-22

sunfish, Lepomis macrochirus. Animals with flexible bodies, like fishes , face a tradeoff for rapid movements. To produce high forces, they must...2014 30-Apr-2015 Approved for Public Release; Distribution Unlimited Final Report: Neuromuscular Control of Rapid Linear Accelerations in Fish The...Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 swimming, acceleration, fish , muscle, stiffness REPORT DOCUMENTATION PAGE 11. SPONSOR

On designing a control system for a new generation of accelerators

International Nuclear Information System (INIS)

Schaller, S.C.; Schultz, D.E.

1987-01-01

A well-conceived plan of attack is essential to the task of designing a control system for a large accelerator. Several aspects of such a plan have been investigated during recent work at LAMPF on design strategies for an Advanced Hadron Facility control system. Aspects discussed in this paper include: identification of requirements, creation and enforcement of standards, interaction with users, consideration of commercial controls products, integration with existing control systems, planning for continual change, and establishment of design reviews. We emphasize the need for the controls group to acquire and integrate accelerator design information from the start of the design process. We suggest that a controls design for a new generation of accelerators be done with a new generation of software tools. 12 refs

COSY Control Status. First results with rapid prototyped man-machine interface for accelerator control

Energy Technology Data Exchange (ETDEWEB)

Hacker, U [Forschungszentrum Juelich, Postfach 1913, 52425 Juelich (Germany); Haberbosch, C [Forschungszentrum Juelich, Postfach 1913, 52425 Juelich (Germany); Henn, K [Forschungszentrum Juelich, Postfach 1913, 52425 Juelich (Germany); Weinert, A [Forschungszentrum Juelich, Postfach 1913, 52425 Juelich (Germany)

1994-12-15

The experience gained with the COSY Control System after a six month commissioning period followed by a six month production period will be presented. The COSY Control System runs approximately 300 VME and VXI target systems using a total of about 1000 CPUs, the systems are driven by the diskless operating environment RT/OS, hosted by eight workcells. Application software is implemented using Object-Orientated programming paradigms. All accelerator components become interface functions as instances of an abstract device model class. Methods defined here present an abstract picture of the accelerator giving immediate access to device states and parameters. Operator interaction is defined by building views and controllers for the model. Higher level functions, such as defining an acceleration cycle, are easily developed and modified with the accelerator connected on-line to the model. In the first year of COSY operation the object based approach for a control system, together with a rapid prototyped man-machine interface has brought to light the potential of new functions such as on-line, real time programming on a running system yielding high programming performance. The advantages of this approach have not been, until now, fully appreciated. ((orig.))

Shaking table control taking account of reaction force. Two-degree-of-freedom controller design of shaking-table acceleration control

International Nuclear Information System (INIS)

Hironaka, Koji; Suzuki, Kitami; Narutaki, Mamoru; Tagawa, Yasutaka

2011-01-01

When carrying out seismic performance examination on a structure by using a shaking table, it is important to reproduce the acceleration faithfully. In the conventional method, we transformed the acceleration wave into a displacement wave and used a hydraulic actuator for displacement control. However, this method had several disadvantages related to disturbance rejection, tracking performance, and stability. In this study, we have developed a full-closed compensation, in which the shaking-table acceleration is assumed the feedback signal for the acceleration wave of the reference signal. Also we adopt the dual model matching (DMM) control technique in order to design a controller. To confirm the disturbance rejection performance and to investigate the effect of enhancing the reproducibility of the shaking-target waveform by DMM control, we perform an experiment using a one-degree-of-freedom specimen placed on a shaking table driven by a hydraulic actuator. (author)

Control system technology for particle accelerators

International Nuclear Information System (INIS)

Tsumura, Yoshihiko; Matsuo, Keiichi; Maruyama, Takayuki.

1995-01-01

Control systems for particle accelerators are being designed around open-architecture systems, which allows easy upgrading, high-speed networks and high-speed processors. Mitsubishi Electric is applying realtime Unix operating systems, fiber-distributed data interface (FDDI), shared memory networks and remote I/O systems to achieve these objectives. In the area of vacuum control systems, which requires large-scale sequence control, the corporation is employing general-purpose programmable logic controllers (PLCs) to achieve cost-effective design. Software for these applications is designed around a library of application program interfaces (APIs) that give users direct access to key system functions. (author)

A New Concept of Controller for Accelerators' Magnet Power Supplies

Science.gov (United States)

Visintini, Roberto; Cleva, Stefano; Cautero, Marco; Ciesla, Tomasz

2016-04-01

The complexity of a particle accelerator implies the remote control of very large numbers of devices, with many different typologies, either distributed along the accelerator or concentrated in locations, often far away from each other. Local and global control systems handle the devices through dedicated communication channels and interfaces. Each controlled device is practically a “smart node” performing a specific task. In addition, very often, those tasks are managed in real-time mode. The performances required to the control interface has an influence on the cost of the distributed nodes as well as on their hardware and software implementation. In large facilities (e.g. CERN) the “smart nodes” derive from specific in-house developments. Alternatively, it is possible to find on the market commercial devices, whose performances (and prices) are spread over a broad range, and spanning from proprietary design (customizable to the user's needs) to open source/design. In this paper, we will describe some applications of smart nodes in the particle accelerators field, with special focus on the power supplies for magnets. In modern accelerators, in fact, magnets and their associated power supplies constitute systems distributed along the accelerator itself, and strongly interfaced with the remote control system as well as with more specific (and often more demanding) orbit/trajectory feedback systems. We will give examples of actual systems, installed and operational on two light sources, Elettra and FERMI, located in the Elettra Research Center in Trieste, Italy.

An "Elective Replacement" Approach to Providing Extra Help in Math: The Talent Development Middle Schools' Computer- and Team-Assisted Mathematics Acceleration (CATAMA) Program.

Science.gov (United States)

Mac Iver, Douglas J.; Balfanz, Robert; Plank, Stephan B.

1999-01-01

Two studies evaluated the Computer- and Team-Assisted Mathematics Acceleration course (CATAMA) in Talent Development Middle Schools. The first study compared growth in math achievement for 96 seventh-graders (48 of whom participated in CATAMA and 48 of whom did not); the second study gathered data from interviews with, and observations of, CATAMA…

Qt based control system software for Low Energy Accelerator Facility

International Nuclear Information System (INIS)

Basu, A.; Singh, S.; Nagraju, S.B.V.; Gupta, S.; Singh, P.

2012-01-01

Qt based control system software for Low Energy Accelerating Facility (LEAF) is operational at Bhabha Atomic Research Centre (BARC), Trombay, Mumbai. LEAF is a 50 keV negative ion electrostatic accelerator based on SNICS ion source. Control system uses Nokia Trolltech's QT 4.x API for control system software. Ni 6008 USB based multifunction cards has been used for control and read back field equipments such as power supplies, pumps, valves etc. Control system architecture is designed to be client server. Qt is chosen for its excellent GUI capability and platform independent nature. Control system follows client server architecture. The paper will describe the control system. (author)

The control computer for the Chalk River electron test accelerator

International Nuclear Information System (INIS)

McMichael, G.E.; Fraser, J.S.; McKeown, J.

1978-02-01

A versatile control and data acquisition system has been developed for a modest-sized linear accelerator using mainly process I/O hardware and software. This report describes the evolution of the present system since 1972, the modifications needed to satisfy the changing requirements of the various accelerator physics experiments and the limitations of such a system in process control. (author)

Large Display Interaction via Multiple Acceleration Curves and Multifinger Pointer Control

Directory of Open Access Journals (Sweden)

Andrey Esakia

2014-01-01

Full Text Available Large high-resolution displays combine high pixel density with ample physical dimensions. The combination of these factors creates a multiscale workspace where interactive targeting of on-screen objects requires both high speed for distant targets and high accuracy for small targets. Modern operating systems support implicit dynamic control-display gain adjustment (i.e., a pointer acceleration curve that helps to maintain both speed and accuracy. However, large high-resolution displays require a broader range of control-display gains than a single acceleration curve can usably enable. Some interaction techniques attempt to solve the problem by utilizing multiple explicit modes of interaction, where different modes provide different levels of pointer precision. Here, we investigate the alternative hypothesis of using a single mode of interaction for continuous pointing that enables both (1 standard implicit granularity control via an acceleration curve and (2 explicit switching between multiple acceleration curves in an efficient and dynamic way. We evaluate a sample solution that augments standard touchpad accelerated pointer manipulation with multitouch capability, where the choice of acceleration curve dynamically changes depending on the number of fingers in contact with the touchpad. Specifically, users can dynamically switch among three different acceleration curves by using one, two, or three fingers on the touchpad.

Studies of ion acceleration in a one meter laser controlled collective accelerator

International Nuclear Information System (INIS)

Destler, W.W.; Rodgers, J.; Striffler, C.D.; Yao, R.L.

1991-01-01

The basic concept behind the Laser Controlled Beam-front Experiment has been described in detail in previous reports. In the experiment, control over the propagation of a virtual cathode at the front of an intense relativistic electron beam is achieved by a time-sequenced plasma channel produced by laser-target interactions. Ions are trapped and accelerated by the very strong electric fields (50-400 MV/m) at the virtual cathode

Nodal in computerized control systems of accelerators

International Nuclear Information System (INIS)

Kagarmanov, A.A.; Koval'tsov, V.I.; Korobov, S.A.

1994-01-01

Brief description of the Nodal language programming structure is presented. Its possibilities as high-level programming language for accelerator control systems are considered. The status of the Nodal language in the HEPI is discussed. 3 refs

Neuro-fuzzy control of structures using acceleration feedback

Science.gov (United States)

Schurter, Kyle C.; Roschke, Paul N.

2001-08-01

This paper described a new approach for the reduction of environmentally induced vibration in constructed facilities by way of a neuro-fuzzy technique. The new control technique is presented and tested in a numerical study that involves two types of building models. The energy of each building is dissipated through magnetorheological (MR) dampers whose damping properties are continuously updated by a fuzzy controller. This semi-active control scheme relies on the development of a correlation between the accelerations of the building (controller input) and the voltage applied to the MR damper (controller output). This correlation forms the basis for the development of an intelligent neuro-fuzzy control strategy. To establish a context for assessing the effectiveness of the semi-active control scheme, responses to earthquake excitation are compared with passive strategies that have similar authority for control. According to numerical simulation, MR dampers are less effective control mechanisms than passive dampers with respect to a single degree of freedom (DOF) building model. On the other hand, MR dampers are predicted to be superior when used with multiple DOF structures for reduction of lateral acceleration.

Control system for a heavy-ion accelerator complex K4 - K10

International Nuclear Information System (INIS)

Kotov, V.M.; Pose, R.

1992-01-01

Control systems for newly created accelerators, perhaps for the first time, may be designed almost only around international standards for communication and control techniques. This is also true for the project of a control system for the accelerator complex K4-K10 at the Joint Institute for Nuclear Research Dubna. Nevertheless, open systems architecture with construction principles being essential for modern systems of such big devices as particle accelerators leaves designers enough possibilities for solving even very sophisticated problems. (author)

New control architecture for the SPS accelerator at CERN

International Nuclear Information System (INIS)

Kissler, K.H.; Rausch, R.

1992-01-01

The Control System for the 450 Gev proton accelerator SPS at CERN was conceived and implemented some 18 years ago. The 16 Bit minicomputers with their proprietary operating system and interconnection with a dedicated network do not permit the use of modern workstations, international communication standards and industrial software packages. The upgrading of the system has therefore become necessary. After a short review of the history and the current state of the SPS control system, the paper describes how CERN's new control architecture, which will be common to all accelerators, will be realized at the SPS. The migration path ensuring a smooth transition to the final system is outlined. Once the SPS upgrade is complete and following some enhancements to the LEP control system, the operator in the SPS/LEP control center will be working in a single uniform control environment. (author)

Methods of Phase and Power Control in Magnetron Transmitters for Superconducting Accelerators

Energy Technology Data Exchange (ETDEWEB)

Kazadevich, G. [MUONS Inc., Batavia; Johnson, R. [MUONS Inc., Batavia; Neubauer, M. [MUONS Inc., Batavia; Lebedev, V. [Fermilab; Schappert, W. [Fermilab; Yakovlev, V. [Fermilab

2017-05-01

Various methods of phase and power control in magnetron RF sources of superconducting accelerators intended for ADS-class projects were recently developed and studied with conventional 2.45 GHz, 1 kW, CW magnetrons operating in pulsed and CW regimes. Magnetron transmitters excited by a resonant (injection-locking) phasemodulated signal can provide phase and power control with the rates required for precise stabilization of phase and amplitude of the accelerating field in Superconducting RF (SRF) cavities of the intensity-frontier accelerators. An innovative technique that can significantly increase the magnetron transmitter efficiency at the widerange power control required for superconducting accelerators was developed and verified with the 2.45 GHz magnetrons operating in CW and pulsed regimes. High efficiency magnetron transmitters of this type can significantly reduce the capital and operation costs of the ADSclass accelerator projects.

Rf control system for a rocket-borne accelerator

International Nuclear Information System (INIS)

Lynch, M.T.; Sorum, L.N.; Keffeler, D.R.

1987-01-01

The Beam Experiments Aboard Rockets (BEAR) accelerator experiment imposes several nonstandard requirements on the rf control system. The experiment is entirely hands-off and must operate under local computer control. The rf control system must be extremely reliable, which implies excellence in design and fabrication as well as redundancy whenever possible. This paper describes the design of the frequency-source, frequency-control, and amplitude-control systems for the BEAR experiment

An Automatic Control System for Conditioning 30 GHz Accelerating Structures

CERN Document Server

Dubrovskiy, A

2008-01-01

A software application programme has been developed to allow fast and automatic high-gradient conditioning of accelerating structures at 30 GHz in CTF3. The specificity of the application is the ability to control the high-power electron beam which produces the 30 GHz RF power used to condition the accelerating structures. The programme permits operation round the clock with minimum manpower requirements. In this paper the fast control system, machine control system, logging system, graphical user control interface and logging data visualization are described. An outline of the conditioning control system itself and of the feedback controlling peak power and pulse length is given. The software allows different types of conditioning strategies to be programmed

Development of a fast voltage control method for electrostatic accelerators

International Nuclear Information System (INIS)

Lobanov, Nikolai R.; Linardakis, Peter; Tsifakis, Dimitrios

2014-01-01

The concept of a novel fast voltage control loop for tandem electrostatic accelerators is described. This control loop utilises high-frequency components of the ion beam current intercepted by the image slits to generate a correction voltage that is applied to the first few gaps of the low- and high-energy acceleration tubes adjoining the high voltage terminal. New techniques for the direct measurement of the transfer function of an ultra-high impedance structure, such as an electrostatic accelerator, have been developed. For the first time, the transfer function for the fast feedback loop has been measured directly. Slow voltage variations are stabilised with common corona control loop and the relationship between transfer functions for the slow and new fast control loops required for optimum operation is discussed. The main source of terminal voltage instabilities, which are due to variation of the charging current caused by mechanical oscillations of charging chains, has been analysed

STUXNET and the Impact on Accelerator Control Systems

CERN Document Server

Lüders, S

2011-01-01

2010 has seen wide news coverage of a new kind of computer attack, named "Stuxnet", targeting control systems. Due to its level of sophistication, it is widely acknowledged that this attack marks the very first case of a cyber-war of one country against the industrial infrastructure of another, although there is still much speculation about the details. Worse yet, experts recognize that Stuxnet might just be the beginning and that similar attacks, eventually with much less sophistication, but with much more collateral damage, can be expected in the years to come. Stuxnet was targeting a special model of the Siemens 400 PLC series. Similar modules are also deployed for accelerator controls like the LHC cryogenics or vacuum systems as well as the detector control systems in LHC experiments. Therefore, the aim of this presentation is to give an insight into what this new attack does and why it is deemed to be special. In particular, the potential impact on accelerator and experiment control sys...

Dynamical Aperture Control in Accelerator Lattices With Multipole Potentials

CERN Document Server

Morozov, I

2017-01-01

We develop tools for symbolic representation of a non-linear accelerator model and analytical methods for description of non-linear dynamics. Information relevant to the dynamic aperture (DA) is then obtained from this model and can be used for indirect DA control or as a complement to direct numerical optimization. We apply two analytical methods and use multipole magnets to satisfy derived analytical constraints. The accelerator model is represented as a product of unperturbed and perturbed exponential operators with the exponent of the perturbed operator given as a power series in the perturbation parameter. Normal forms can be applied to this representation and the lattice parameters are used to control the normal form Hamiltonian and normal form transformation. Hamiltonian control is used to compute a control term or controlled operator. Lattice parameters are then fitted to satisfy the imposed control constraints. Theoretical results, as well as illustrative examples, are presented.

Validation of a new control system for Elekta accelerators facilitating continuously variable dose rate

DEFF Research Database (Denmark)

Bertelsen, Anders; Lorenzen, Ebbe L; Brink, Carsten

2011-01-01

) as well as BVDR. Using CVDR opposed to BVDR for VMAT has the potential of reducing the treatment time but may lead to lower dosimetric accuracy due to faster moving accelerator parts. Using D7 and a test version of Integrity, differences in ability to control the accelerator, treatment efficiency......Elekta accelerators controlled by the current clinically used accelerator control system, Desktop 7.01 (D7), uses binned variable dose rate (BVDR) for volumetric modulated arc therapy (VMAT). The next version of the treatment control system (Integrity) supports continuously variable dose rate (CVDR...

Control system modelling for superconducting accelerator

International Nuclear Information System (INIS)

Czarski, T.; Pozniak, K.; Romaniuk, R.

2006-01-01

A digital control of superconducting cavities for a linear accelerator is presented. The LLRF - Low Level Radio Frequency system for FLASH project in DESY is introduced. FPGA based controller supported by MATLAB system was developed to investigate the novel firmware implementation. Algebraic model in complex domain is proposed for the system analyzing. Calibration procedure of a signal path is considered for a multi-channel control. Identification of the system parameters is carried out by the least squares method application. Control tables: Feed-Forward and Set- Point are determined for the required cavity performance, according to the recognized process. Feedback loop is tuned by fitting a complex gain of a corrector unit. Adaptive control algorithm is applied for feed-forward and feedback modes. Experimental results are presented for a cavity representative operation. (orig.)

Trends in accelerator control systems

International Nuclear Information System (INIS)

Crowley-Milling, M.C.

1984-04-01

Over the years, we have seen a revolution in control systems that has followed the ever decreasing cost of computer power and memory. It started with the data gathering, when people distrusted the computer to perform control actions correctly, through the stage of using a computer to perform control actions correctly, through the stage of using a computer system to provide a convenient remote look and adjust facility, to the present day, when more and more emphasis is being placed on using a computer system to simulate or model all or parts of the accelerator, feed in the required performance and calling for the computers to set the various parameters and then measure the actual performance, with iteration if necessary. The progress that has been made in the fields of architecture, communications, computers, interface, software design and operator interface is reviewed

A study on optimal control of the aero-propulsion system acceleration process under the supersonic state

Directory of Open Access Journals (Sweden)

Fengyong Sun

2017-04-01

Full Text Available In order to solve the aero-propulsion system acceleration optimal problem, the necessity of inlet control is discussed, and a fully new aero-propulsion system acceleration process control design including the inlet, engine, and nozzle is proposed in this paper. In the proposed propulsion system control scheme, the inlet, engine, and nozzle are simultaneously adjusted through the FSQP method. In order to implement the control scheme design, an aero-propulsion system component-level model is built to simulate the inlet working performance and the matching problems between the inlet and engine. Meanwhile, a stabilizing inlet control scheme is designed to solve the inlet control problems. In optimal control of the aero-propulsion system acceleration process, the inlet is an emphasized control unit in the optimal acceleration control system. Two inlet control patterns are discussed in the simulation. The simulation results prove that by taking the inlet ramp angle as an active control variable instead of being modulated passively, acceleration performance could be obviously enhanced. Acceleration objectives could be obtained with a faster acceleration time by 5%.

Present SLAC accelerator computer control system features

International Nuclear Information System (INIS)

Davidson, V.; Johnson, R.

1981-02-01

The current functional organization and state of software development of the computer control system of the Stanford Linear Accelerator is described. Included is a discussion of the distribution of functions throughout the system, the local controller features, and currently implemented features of the touch panel portion of the system. The functional use of our triplex of PDP11-34 computers sharing common memory is described. Also included is a description of the use of pseudopanel tables as data tables for closed loop control functions

Feasibility and advantages of commercial process I/O systems for accelerator control

International Nuclear Information System (INIS)

Belshe, R.A.; Elischer, V.P.; Jacobson, V.

1975-03-01

Control systems for large particle accelerators must be able to handle analog and digital signals and timing coordination for devices which are spread over a large physical area. Many signals must be converted and transmitted to and from a central control area during each accelerator cycle. Digital transmission is often used to combat common mode and RF interference. Most accelerators in use today have met these requirements with custom process I/O hardware, data transmission systems, and computer interfaces. In-house development of hardware and software has been a very costly and time consuming process, but due to the lack of available commercial equipment, there was often no other alternative. Today, a large portion of these development costs can be avoided. Small control computers are now available off the shelf which have extensive process control I/O hardware and software capability. Computer control should be designed into accelerator systems from the beginning, using operating systems available from manufacturer. With most of the systems programming done, the designers can begin immediately on the applications software. (U.S.)

Controls and Beam Diagnostics for Therapy-Accelerators

CERN Document Server

Eickhoff, H

2000-01-01

During the last four years GSI has developed a new procedure for cancer treatment by means of the intensity controlled rasterscan-method. This method includes active variations of beam parameters during the treatment session and the integration of 'on-line' PET monitoring. Starting in 1997 several patients have been successfully treated within this GSI experimental cancer treatment program; within this program about 350 patients shall be treated in the next 5 years. The developments and experiences of this program accompanied by intensive discussions with the medical community led to a proposal for a hospital based light ion accelerator facility for the clinic in Heidelberg. An essential part for patients treatments is the measurement of the beam properties within acceptance and constancy tests and especially for the rasterscan method during the treatment sessions. The presented description of the accelerator controls and beam diagnostic devices mainly covers the requests for the active scanning method, which...

Concurrent control system for the JAERI tandem accelerator

International Nuclear Information System (INIS)

Hanashima, Susumu; Shozi, Tokio; Shiozaki, Yasuo; Saito, Motoi; Oogane, Yasuo; Sekiguchi, Satoshi.

1994-01-01

A new control system for the JAERI tandem accelerator is constructed. The system utilizes concurrent processing technology with multiprocessor. Transputers are used both for central processor and I/O front end processors. (author)

Research on Acceleration Compensation Strategy of Electric Vehicle Based on Fuzzy Control Theory

Science.gov (United States)

Zhu, Tianjun; Li, Bin; Zong, Changfu; Wei, Zhicheng

2017-09-01

Nowadays, the driving technology of electric vehicle is developing rapidly. There are many kinds of methods in driving performance control technology. The paper studies the acceleration performance of electric vehicle. Under the premise of energy management, an acceleration power compensation method by fuzzy control theory based on driver intention recognition is proposed, which can meet the driver’s subjective feelings better. It avoids the problem that the pedal opening and power output are single correspondence when the traditional vehicle accelerates. Through the simulation test, this method can significantly improve the performance of acceleration and output torque smoothly in non-emergency acceleration to ensure vehicle comfortable and stable.

The impact of new computer technology on accelerator control

International Nuclear Information System (INIS)

Theil, E.; Jacobson, V.; Paxson, V.

1987-01-01

This paper describes some recent developments in computing and stresses their application to accelerator control systems. Among the advances that promise to have a significant impact are: i) low cost scientific workstations; ii) the use of ''windows'', pointing devices and menus in a multitasking operating system; iii) high resolution large-screen graphics monitors; iv) new kinds of high bandwidth local area networks. The relevant features are related to a general accelerator control system. For example, the authors examine the implications of a computing environment which permits and encourages graphical manipulation of system components, rather than traditional access through the writing of programs or ''canned'' access via touch panels

The impact of new computer technology on accelerator control

International Nuclear Information System (INIS)

Theil, E.; Jacobson, V.; Paxson, V.

1987-04-01

This paper describes some recent developments in computing and stresses their application in accelerator control systems. Among the advances that promise to have a significant impact are (1) low cost scientific workstations; (2) the use of ''windows'', pointing devices and menus in a multi-tasking operating system; (3) high resolution large-screen graphics monitors; (4) new kinds of high bandwidth local area networks. The relevant features are related to a general accelerator control system. For example, this paper examines the implications of a computing environment which permits and encourages graphical manipulation of system components, rather than traditional access through the writing of programs or ''canned'' access via touch panels

Control system user interface for accelerator commissioning and operation

International Nuclear Information System (INIS)

Dobrott, D.; Keeley, D.; Kolte, G.; Mikic, Z.; Lee, M.; Corbett, J.; Howry, S.; King, A.

1991-01-01

An Interactive Accelerator Interface Module (AIM) has been developed in a workstation environment for the purposes of assisting in the commissioning and operation of any storage ring/collider system. The function of AIM is to integrate modeling and simulation codes into accelerator and beamline control systems for the purpose of rapid on-line data analysis and error-correction, resulting in significant time-saving. A system dependent module provides for the translation of specific control system data files to appropriate input format for application programs within AIM. Interactive screen graphics, including system function diagrams, menus, beamline element status and update information are standard in AIM. AIM is currently connected to the Stanford Linear Collider (SLC) control system, but is easily transportable to other facilities. This paper describes the development of AIM and its applications on SLC

Personal computer control system for small size tandem accelerator

Energy Technology Data Exchange (ETDEWEB)

Takayama, Hiroshi; Kawano, Kazuhiro; Shinozaki, Masataka [Nissin - High Voltage Co. Ltd., Kyoto (Japan)

1996-12-01

As the analysis apparatus using tandem accelerator has a lot of control parameter, numbers of control parts set on control panel are so many to make the panel more complex and its operativity worse. In order to improve these faults, development and design of a control system using personal computer for the control panel mainly constituted by conventional hardware parts were tried. Their predominant characteristics are shown as follows: (1) To make the control panel construction simpler and more compact, because the hardware device on the panel surface becomes the smallest limit as required by using a personal computer for man-machine interface. (2) To make control speed more rapid, because sequence control is closed within each block by driving accelerator system to each block and installing local station of the sequencer network at each block. (3) To make expandability larger, because of few improvement of the present hardware by interrupting the sequencer local station into the net and correcting image of the computer when increasing a new beamline. And, (4) to make control system cheaper, because of cheaper investment and easier programming by using the personal computer. (G.K.)

An Integration Testing Facility for the CERN Accelerator Controls System

CERN Document Server

Stapley, N; Bau, J C; Deghaye, S; Dehavay, C; Sliwinski, W; Sobczak, M

2009-01-01

A major effort has been invested in the design, development, and deployment of the LHC Control System. This large control system is made up of a set of core components and dependencies, which although tested individually, are often not able to be tested together on a system capable of representing the complete control system environment, including hardware. Furthermore this control system is being adapted and applied to CERN's whole accelerator complex, and in particular for the forthcoming renovation of the PS accelerators. To ensure quality is maintained as the system evolves, and toimprove defect prevention, the Controls Group launched a project to provide a dedicated facility for continuous, automated, integration testing of its core components to incorporate into its production process. We describe the project, initial lessons from its application, status, and future directions.

The Talent Development Middle School. An Elective Replacement Approach to Providing Extra Help in Math--The CATAMA Program (Computer- and Team-Assisted Mathematics Acceleration). Report No. 21.

Science.gov (United States)

Mac Iver, Douglas J.; Balfanz, Robert; Plank, Stephen B.

In Talent Development Middle Schools, students needing extra help in mathematics participate in the Computer- and Team-Assisted Mathematics Acceleration (CATAMA) course. CATAMA is an innovative combination of computer-assisted instruction and structured cooperative learning that students receive in addition to their regular math course for about…

Lessons learned on the Ground Test Accelerator control system

International Nuclear Information System (INIS)

Kozubal, A.J.; Weiss, R.E.

1994-01-01

When we initiated the control system design for the Ground Test Accelerator (GTA), we envisioned a system that would be flexible enough to handle the changing requirements of an experimental project. This control system would use a developers' toolkit to reduce the cost and time to develop applications for GTA, and through the use of open standards, the system would accommodate unforeseen requirements as they arose. Furthermore, we would attempt to demonstrate on GTA a level of automation far beyond that achieved by existing accelerator control systems. How well did we achieve these goals? What were the stumbling blocks to deploying the control system, and what assumptions did we make about requirements that turned out to be incorrect? In this paper we look at the process of developing a control system that evolved into what is now the ''Experimental Physics and Industrial Control System'' (EPICS). Also, we assess the impact of this system on the GTA project, as well as the impact of GTA on EPICS. The lessons learned on GTA will be valuable for future projects

The Fermilab Accelerator control system

Science.gov (United States)

Bogert, Dixon

1986-06-01

With the advent of the Tevatron, considerable upgrades have been made to the controls of all the Fermilab Accelerators. The current system is based on making as large an amount of data as possible available to many operators or end-users. Specifically there are about 100 000 separate readings, settings, and status and control registers in the various machines, all of which can be accessed by seventeen consoles, some in the Main Control Room and others distributed throughout the complex. A "Host" computer network of approximately eighteen PDP-11/34's, seven PDP-11/44's, and three VAX-11/785's supports a distributed data acquisition system including Lockheed MAC-16's left from the original Main Ring and Booster instrumentation and upwards of 1000 Z80, Z8002, and M68000 microprocessors in dozens of configurations. Interaction of the various parts of the system is via a central data base stored on the disk of one of the VAXes. The primary computer-hardware communication is via CAMAC for the new Tevatron and Antiproton Source; certain subsystems, among them vacuum, refrigeration, and quench protection, reside in the distributed microprocessors and communicate via GAS, an in-house protocol. An important hardware feature is an accurate clock system making a large number of encoded "events" in the accelerator supercycle available for both hardware modules and computers. System software features include the ability to save the current state of the machine or any subsystem and later restore it or compare it with the state at another time, a general logging facility to keep track of specific variables over long periods of time, detection of "exception conditions" and the posting of alarms, and a central filesharing capability in which files on VAX disks are available for access by any of the "Host" processors.

The Fermilab accelerator control system

International Nuclear Information System (INIS)

Bogert, D.

1986-01-01

With the advent of the Tevatron, considerable upgrades have been made to the controls of all the Fermilab Accelerators. The current system is based on making as large an amount of data as possible available to many operators or end-users. Specifically there are about 100000 separate readings, settings, and status and control registers in the various machines, all of which can be accessed by seventeen consoles, some in the Main Control Room and others distributed throughout the complex. A ''Host'' computer network of approximately eighteen PDP-11/34's, seven PDP-11/44's, and three VAX-11/785's supports a distributed data acquisition system including Lockheed MAC-16's left from the original Main Ring and Booster instrumentation and upwards of 1000 Z80, Z8002, and M68000 microprocessors in dozens of configurations. Interaction of the various parts of the system is via a central data base stored on the disk of one of the VAXes. The primary computer-hardware communication is via CAMAC for the new Tevatron and Antiproton Source; certain subsystems, among them vacuum, refrigeration and quench protection, reside in the distributed microprocessors and communicate via GAS, an in-house protocol. An important hardware feature is an accurate clock system making a large number of encoded ''events'' in the accelerator supercycle available for both hardware modules and computers. System software features include the ability to save the current state of the machine or any subsystem and later restore it or compare it with the state at another time, a general logging facility to keep track of specific variables over long periods of time, detection of 'exception conditions' and the posting of alarms, and a central filesharing capability in which files on VAX disks are available for access by any of the ''Host'' processors. (orig.)

Accelerated diffusion controlled creep of polycrystalline materials. Communication 1. Model of diffusion controlled creep acceleration

International Nuclear Information System (INIS)

Smirnova, E.S.; Chuvil'deev, V.N.

1998-01-01

The model is suggested which describes the influence of large-angle grain boundary migration on a diffusion controlled creep rate in polycrystalline materials (Coble creep). The model is based on the concept about changing the value of migrating boundary free volume when introducing dislocations distributed over the grain bulk into this boundary. Expressions are obtained to calculate the grain boundary diffusion coefficient under conditions of boundary migration and the parameter, which characterized the value of Coble creep acceleration. A comparison is made between calculated and experimental data for Cd, Co and Fe

Stuxnet and the impact on accelerator control systems

International Nuclear Information System (INIS)

Lueders, S.

2012-01-01

2010 has seen wide news coverage of a new kind of computer attack, named 'Stuxnet', targeting control systems. Due to its level of sophistication, it is widely acknowledged that this attack marks the very first case of a cyber-war of one country against the industrial infrastructure of another, although there is still much speculation about the details. Worse yet, experts recognize that Stuxnet might just be the beginning and that similar attacks, eventually with much less sophistication, but with much more collateral damage, can be expected in the years to come. Stuxnet was targeting a special model of the Siemens 400 PLC series. Similar modules are also deployed for accelerator controls like the LHC cryogenics or vacuum systems as well as the detector control systems in LHC experiments. Therefore, the aim of this presentation is to give an insight into what this new attack does and why it is deemed to be special. In particular, the potential impact on accelerator and experiment control systems will be discussed, and means will be presented on how to properly protect against similar attacks. Deploying a 'Defense-in-depth' approach appears to be mandatory. (author)

Computer networks in future accelerator control systems

International Nuclear Information System (INIS)

Dimmler, D.G.

1977-03-01

Some findings of a study concerning a computer based control and monitoring system for the proposed ISABELLE Intersecting Storage Accelerator are presented. Requirements for development and implementation of such a system are discussed. An architecture is proposed where the system components are partitioned along functional lines. Implementation of some conceptually significant components is reviewed

Database foundation for the configuration management of the CERN accelerator controls systems

International Nuclear Information System (INIS)

Zaharieva, Z.; Martin Marquez, M.; Peryt, M.

2012-01-01

The Controls Configuration Database (CCDB) and its interfaces have been developed over the last 25 years in order to become nowadays the basis for the Configuration Management of the Control System for all accelerators at CERN. The CCDB contains data for all configuration items and their relationships, required for the correct functioning of the Control System. The configuration items are quite heterogeneous, depicting different areas of the Control System - ranging from 3000 Front-End Computers, 75000 software devices allowing remote control of the accelerators, to valid states of the Accelerators Timing System. The article will describe the different areas of the CCDB, their inter-dependencies and the challenges to establish the data model for such a diverse configuration management database, serving a multitude of clients. The CCDB tracks the life of the configuration items by allowing their clear identification, triggering of change management processes as well as providing status accounting and audits. This required the development and implementation of a combination of tailored processes and tools. The Controls System is a data-driven one - the data stored in the CCDB is extracted and propagated to the controls hardware in order to configure it remotely. Therefore a special attention is placed on data security and data integrity as an incorrectly configured item can have a direct impact on the operation of the accelerators. (authors)

Application of Smalltalk language for accelerator control

International Nuclear Information System (INIS)

Mejuev, I.; Abe, I.; Nakahara, K.

1997-01-01

This paper describes the results of studies for object-oriented control system creation. Using VisualWorks environment based on Smalltalk we created a set of programs, such as Control Model Editor, Control Model Scanner and Control Views, for developing and running an object-oriented model of an accelerator. Our system allows the user to easily create a class library which can be used to develop a number of control programs. The object model defines the object under control, the control logic and graphics for displaying control objects' states. Our experience shows that object-oriented software development is faster compared with traditional languages, and provides more functionality. VisualWorks is a multiplatform environment, and all applications can be ported to different operating systems with only minor changes. VisualWorks also provides high performance, which is important for time-critical control applications. (orig.)

Advanced concepts in accelerator timing control

International Nuclear Information System (INIS)

Frankel, R.; Salwen, C.

1988-01-01

The control system for the Booster accelerator presently under construction at BNL includes a timing section with serial high speed coded data distribution, computer based encoders for both real time and field driven clocks and a method of easily tracking the performance and reliability of these timing streams. We have developed a simple method for the generation of timing which operates to produce pulses which may be repeated as desired with minimal latency

Accelerated middle Miocene exhumation of the Talesh Mountains constrained by U-Th/He thermochronometry: Evidence for the Arabia-Eurasia collision in the NW Iranian Plateau

Science.gov (United States)

Madanipour, Saeed; Ehlers, Todd A.; Yassaghi, Ali; Enkelmann, Eva

2017-08-01

The Talesh Mountains at the NW margin of the Iranian Plateau curve around the southwestern corner of the South Caspian Block and developed in response to the collision of the Arabian-Eurasian Plates. The timing, rates, and regional changes in late Cenozoic deformation of the Talesh Mountains are not fully understood. In this study, we integrate 23 new apatite and zircon bedrock U-Th/He ages and structurally restored geologic cross sections with previously published detrital apatite fission track data to reconstruct the deformation history of the Talesh Mountains. Our results reveal that slow rock exhumation initiated during the late Oligocene ( 27-23 Ma) and then accelerated in the middle Miocene ( 12 Ma). These events resulted in the present-day high-elevation and curved geometry of the mountains. The spatial and temporal distribution of cooling ages suggest that the Oligocene bending of the Talesh Mountains was earlier than in the eastern Alborz, Kopeh Dagh, and central Alborz Mountains that initiated during the late Cenozoic. Late Oligocene and middle Miocene deformation episodes recorded in the Talesh Mountains can be related to the collisional phases of the Arabian and Eurasian Plates. The lower rate of exhumation recorded in the Talesh Mountains occurred during the initial soft collision of the Arabian-Eurasian Plates in the late Oligocene. The accelerated exhumation that occurred during final collision since the middle Miocene resulted from collision of the harder continental margin.

Wideband Motion Control by Position and Acceleration Input Based Disturbance Observer

Science.gov (United States)

Irie, Kouhei; Katsura, Seiichiro; Ohishi, Kiyoshi

The disturbance observer can observe and suppress the disturbance torque within its bandwidth. Recent motion systems begin to spread in the society and they are required to have ability to contact with unknown environment. Such a haptic motion requires much wider bandwidth. However, since the conventional disturbance observer attains the acceleration response by the second order derivative of position response, the bandwidth is limited due to the derivative noise. This paper proposes a novel structure of a disturbance observer. The proposed disturbance observer uses an acceleration sensor for enlargement of bandwidth. Generally, the bandwidth of an acceleration sensor is from 1Hz to more than 1kHz. To cover DC range, the conventional position sensor based disturbance observer is integrated. Thus, the performance of the proposed Position and Acceleration input based disturbance observer (PADO) is superior to the conventional one. The PADO is applied to position control (infinity stiffness) and force control (zero stiffness). The numerical and experimental results show viability of the proposed method.

Database Foundation For The Configuration Management Of The CERN Accelerator Controls Systems

CERN Document Server

Zaharieva, Z; Peryt, M

2011-01-01

The Controls Configuration Database (CCDB) and its interfaces have been developed over the last 25 years in order to become nowadays the basis for the Configuration Management of the Controls System for all accelerators at CERN. The CCDB contains data for all configuration items and their relationships, required for the correct functioning of the Controls System. The configuration items are quite heterogeneous, depicting different areas of the Controls System – ranging from 3000 Front-End Computers, 75 000 software devices allowing remote control of the accelerators, to valid states of the Accelerators Timing System. The article will describe the different areas of the CCDB, their interdependencies and the challenges to establish the data model for such a diverse configuration management database, serving a multitude of clients. The CCDB tracks the life of the configuration items by allowing their clear identification, triggering of change management processes as well as providing status accounting and aud...

Thermionic gun control system for the CEBAF [Continuous Electron Beam Accelerator Facility] injector

International Nuclear Information System (INIS)

Pico, R.; Diamond, B.; Fugitt, J.; Bork, R.

1989-01-01

The injector for the CEBAF accelerator must produce a high-quality electron beam to meet the overall accelerator specifications. A Hermosa electron gun with a 2 mm-diameter cathode and a control aperture has been chosen as the electron source. This must be controlled over a wide range of operating conditions to meet the beam specifications and to provide flexibility for accelerator commissioning. The gun is controlled using Computer Automated Measurement and Control (CAMAC IEEE-583) technology. The system employs the CAMAC-based control architecture developed at CEBAF. The control system has been tested, and early operating data on the electron gun and the injector beam transport system has been obtained. This system also allows gun parameters to be stored at the operator location, without paralyzing operation. This paper describes the use of this computer system in the control of the CEBAF electron gun. 2 refs., 6 figs., 1 tab

Control system for the NBS microtron accelerator

International Nuclear Information System (INIS)

Martin, E.R.; Trout, R.E.; Wilson, B.L.; Ayres, R.L.; Yoder, N.R.

1985-01-01

As various subsystems of the National Bureau of Standards/Los Alamos racetrack microtron accelerator are being brought on-line, we are gaining experience with some of the innovations implemented in the control system. Foremost among these are the joystick-based operator controls, the hierarchical distribution of control system intelligence, and the independent secondary stations, permitting sectional stand-alone operation. The result of the distributed database philosophy and parallel data links has been very fast data updates, permitting joystick interaction with system elements. The software development was greatly simplified by using the hardware arbitration of several parallel processors in the Multibus system to split the software tasks into independent modules

Multi-agent cooperation for particle accelerator control

CERN Document Server

Skarek, Paul

1996-01-01

We present practical investigations in a real industrial controls environment for justifying theoretical DAI (Distributed Artificial Intelligence) results, and we discuss theoretical aspects of practical investigations for accelerator control and operation. A generalized hypothesis is introduced based on a unified view of control, monitoring, diagnosis, maintenance and repair tasks leading to a general method of cooperation for expert systems by exchanging hypotheses. This has been tested for task and result sharing cooperation scenarios. Generalized hypotheses also allow us to treat the repetitive diagnosis-recovery cycle as task sharing cooperation. Problems with such a loop or even recursive calls between the different agents are discussed.

Nonlinear predictive control in the LHC accelerator

CERN Document Server

Blanco, E; Cristea, S; Casas, J

2009-01-01

This paper describes the application of a nonlinear model-based control strategy in a real challenging process. A predictive controller based on a nonlinear model derived from physical relationships, mainly heat and mass balances, has been developed and commissioned in the inner triplet heat exchanger unit (IT-HXTU) of the large hadron collider (LHC) particle accelerator at European Center for Nuclear Research (CERN). The advanced regulation\\ maintains the magnets temperature at about 1.9 K. The development includes a constrained nonlinear state estimator with a receding horizon estimation procedure to improve the regulator predictions.

Status of control systems for industrial electron accelerators at EBC, Kharghar

International Nuclear Information System (INIS)

Jain, Arvind; Kumar, Mukesh; Kaurav, P.S.; Sharma, Vijay; Chawla, A.S.; Sethi, R.C.

2005-01-01

The Bhabha Atomic Research Centre (BARC) is setting up two industrial electron accelerators at the Electron Beam Center (EBC) Kharghar. These are a 10 MeV, 10 KW beam power RF linac and a 30 KW, DC, Dynamitron type of machine. The present status of the control systems of these accelerators are presented. Some novel features in the design of the control system include (a) the software and hardware of the control system has been designed such that the same package can be used for the two widely different machines. Thus the control system developed can be used for any new accelerator also by reformatting the built in data base (b) an attempt is being made towards push button operation to minimize the need for machine operators. This is achieved by a sequential start-up and shut down procedure with appropriate time lags built into the software. The PC based centralized control system has been tested and now gives automated operation of the 22 sub-systems of the linac and operating experience of the system for the last one year has been achieved. Similarly, the control system of the 3 MeV DC machine having about 20 subsystems are in the final stage of commissioning and testing. (author)

The Automatic Radiation Control System Of The Inr Linear Accelerator (troitsk).

CERN Document Server

Grachev, M I; Kuptsov, S I; Peleshko, V N; Shishkin, K I; Shmelev, M O; Skorkin, V M

2004-01-01

The radiation monitor system (RMS) at accelerator INR is a part of radiation safety system of experimental complex INR. RMS is intended for continuous monitoring of radiation field behind biological protection of linear accelerator INR with the personnel dose control and alarm purposes. Three-level system RMS consists of the operator computer, microprocessor data acquisition modules and networks of UDBN-02R neutron detectors and BDRC-01P photon detectors, located inside and behind biological protection of the accelerator (fig. 1).

A Shot Parameter Specification Subsystem for automated control of PBFA [Particle Beam Fusion Accelerator] II accelerator shots

International Nuclear Information System (INIS)

Spiller, J.L.

1987-01-01

The Shot Parameter Specification Subsystem (SPSS) is an integral part of the automatic control system developed for the Particle Beam Fusion Accelerator II (PBFA II) by the Control Monitor (C/M) Software Development Team. This system has been designed to fully utilize the accelerator by tailoring shot parameters to the needs of the experimenters. The SPSS is the key to this flexibility. Automatic systems will be required on many pulsed power machines for the fastest turnaround, the highest reliability, and most cost effective operation. These systems will require the flexibility and the ease of use that is part of the SPSS. The PBFA II control system has proved to be an effective modular system, flexible enough to meet the demands of both the fast track construction of PBFA II and the control needs of Hermes III at the Simulation Technology Laboratory. This system is expected to meet the demands of most future machine changes

Design concept of radiation control system for the high intensity proton accelerator facility

Energy Technology Data Exchange (ETDEWEB)

Miyamoto, Yukihiro; Ikeno, Koichi; Akiyama, Shigenori; Harada, Yasunori [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2002-11-01

Description is given for the characteristic radiation environment for the High Intensity Proton Accelerator Facility and the design concept of the radiation control system of it. The facility is a large scale accelerator complex consisting of high energy proton accelerators carrying the highest beam intensity in the world and the related experimental facilities and therefore provides various issues relevant to the radiation environment. The present report describes the specifications for the radiation control system for the facility, determined in consideration of these characteristics. (author)

Global Accelerator Network, Control Systems And Beam Diagnostics

CERN Document Server

Raich, U

2003-01-01

Falling funds force all accelerator centers to look for new sources of financing and for the most efficient way of implementing new projects. This very often leads to collaborations between institutes scattered around the globe, a problem well known to big high energy physics experiments. The collaborations working on big detectors e.g. for LHC started thinking about detector acquisition and control systems which can be remotely used from their respective home institutes with minimal support on the spot. This idea was taken up by A. Wagner from DESY for the TESLA machine, who proposed the “Global Accelerator Network” (GAN) enabling users from around the world to run an accelerator remotely. Questions around this subject that immediately come to mind Is the GAN only relevant to big labs ? Or is it reasonable e.g. for operators or engineers in charge to do certain manipulations from home? Are our instruments ready for the GAN? Does the fact of being “GAN ready” increa...

The Control System of CERN Accelerators Vacuum (Current Status and Recent Improvements)

CERN Document Server

Gomes, P; Blanchard, S; Boccioli, M; Girardot, G; Vestergard, H; Kopylov, L; Mikheev, M

2011-01-01

The vacuum control system of most of the CERN accelerators is based on Siemens PLCs and on PVSS SCADA. After the transition from the LHC commissioning phase to its regular operation, there has been a number of additions and improvements to the vacuum control system. They were driven by new technical requirements and by feedback from the accelerator operators and vacuum specialists. New control functions have been implemented in the PLCs; new tools have been developed for the SCADA, while its ergonomics and navigation have been enhanced.

Merging AI and numerical modeling for accelerator control

International Nuclear Information System (INIS)

Schultz, D.E.; Silbar, R.R.

1987-01-01

The authors report the beginnings of an experiment to evaluate the power and limitations of artificial intelligence techniques combined with beam-line modeling for solving problems in accelerator control. Using the Knowledge Engineering Environment (KEE) system, they have built a knowledge base that describes the characteristics and the relationships of about 30 devices in a typical accelerator beam line. Each device in the line is categorized and pertinent attributes for each category are defined. Specific values for each device are assigned in the knowledge base to represent static characteristics. Device-specific slots are also provided for dynamic attributes. The definition of these slots reflects the data type and any limitations or restrictions on the range of the data. The authors model relationships between the various beam-line devices using the techniques of rules, active values, and object-oriented models. The knowledge base provides a framework for analyzing faults and offering suggestions to assist in tuning, based on information provided by the accelerator physicists (domain experts) responsible for designing and tuning this beam line. Our knowledge base has a powerful graphical interface. It allows the operator to mouse on an icon for a particular icon in the schematic of the beam line and obtain device-specific information and control over that device. The beam optics code Transport is used to model the beam line numerically. 11 refs., 7 figs

Tools for man-machine interface development in accelerator control applications

International Nuclear Information System (INIS)

Kopylov, L.; Mikhev, M.; Trofimov, N.; Yurpalov, V.

1994-01-01

For the UNK Project a development of the Accelerator Control Applications is in the progress. These applications will use a specific Graphical User Interface for data presentation and accelerator parameter management. A number of tools have been developed based on the Motif Tool Kit. They contain a set of problem oriented screen templates and libraries. Using these tools, full scale prototype applications of the UNK Tune and Orbit measurement and correction were developed and are described, as examples. A subset of these allows the creation of the synoptic control screens from the Autocad pictures files and Oracle DB equipment descriptions. The basic concepts and a few application examples are presented. ((orig.))

Status of the Advanced Photon Source and its accelerator control system

International Nuclear Information System (INIS)

McDowell, W.; Knott, M.; Kraimer, K.M.

1993-01-01

This paper presents the current status of the Advanced Photon Source (APS), its control system and the Experimental Physics and Industrial Control System (EPICS) tools being used to implement this control system. The status of the physical plant and each of the accelerators as well as detailed descriptions of the software tools used to build the accelerator control system are presented. The control system uses high-performance graphic workstations and the X-windows graphical user interface (GUI) at the operator interface level. It connects to VME/VXI-based microprocessors at the field level using TCP/IP protocols over high-performance networks. This strategy assures the flexibility and expansibility of the control system. A defined interface between the system components will allow the system to evolve with the direct addition of future, improved equipment and new capabilities

First experience with the MATLAB Middle Layer at ANKA

International Nuclear Information System (INIS)

Marsching, S.; Huttel, E.; Klein, M.; Mueller, A.S.; Smale, N.J.

2012-01-01

ANKA is a synchrotron radiation facility at the Karlsruhe Institute of Technology. The MATLAB Middle Layer (MML) is a collection of scripts for the MATLAB programming environment, designed to control and measure parameters of an accelerator. MML has been adapted for use at ANKA and the commissioning process was quite simple and would have been even simpler if we had used one of the control systems directly supported by MML. At ANKA MML is used for accelerator physics studies and regular tasks like beam-based alignment and response matrix analysis using LOCO. Furthermore, we intend to study the MML as default orbit correction tool for user operation. We report on the experience made during the commissioning process and present the latest results obtained while using the MML for machine studies. MML simplifies the task of performing a beam-based alignment dramatically compared to our old solution which required the user to copy the measured data into specific files for further evaluation

Artificial intelligence approach to accelerator control systems

International Nuclear Information System (INIS)

Schultz, D.E.; Hurd, J.W.; Brown, S.K.

1987-01-01

An experiment was recently started at LAMPF to evaluate the power and limitations of using artificial intelligence techniques to solve problems in accelerator control and operation. A knowledge base was developed to describe the characteristics and the relationships of the first 30 devices in the LAMPF H+ beam line. Each device was categorized and pertinent attributes for each category defined. Specific values were assigned in the knowledge base to represent each actual device. Relationships between devices are modeled using the artificial intelligence techniques of rules, active values, and object-oriented methods. This symbolic model, built using the Knowledge Engineering Environment (KEE) system, provides a framework for analyzing faults, tutoring trainee operators, and offering suggestions to assist in beam tuning. Based on information provided by the domain expert responsible for tuning this portion of the beam line, additional rules were written to describe how he tunes, how he analyzes what is actually happening, and how he deals with failures. Initial results have shown that artificial intelligence techniques can be a useful adjunct to traditional methods of numerical simulation. Successful and efficient operation of future accelerators may depend on the proper merging of symbolic reasoning and conventional numerical control algorithms

Differences in grip force control between young and late middle-aged adults.

Science.gov (United States)

Zheng, Lianrong; Li, Kunyang; Wang, Qian; Chen, Wenhui; Song, Rong; Liu, Guanzheng

2017-09-01

Grip force control is a crucial function for human to guarantee the quality of life. To examine the effects of age on grip force control, 10 young adults and 11 late middle-aged adults participated in visually guided tracking tasks using different target force levels (25, 50, and 75% of the subject's maximal grip force). Multiple measures were used to evaluate the tracking performance during force rising phase and force maintenance phase. The measurements include the rise time, fuzzy entropy, mean force percentage, coefficient of variation, and target deviation ratio. The results show that the maximal grip force was significantly lower in the late middle-aged adults than in the young adults. The time of rising phase was systematically longer among late middle-aged adults. The fuzzy entropy is a useful indicator for quantitating the force variability of the grip force signal at higher force levels. These results suggest that the late middle-aged adults applied a compensatory strategy that allow allows for sufficient time to reach the required grip force and reduce the impact of the early and subtle degenerative changes in hand motor function.

Overview of Fermi National Accelerator Lab Control System

International Nuclear Information System (INIS)

Lucas, P.W.

1990-01-01

Various facets of the control of the Fermilab accelerators, in particular the Tevatron, are presented. Since Fermilab contains a superconducting machine and a sophisticated injection complex, much of the controls functionality will of necessity be the same at the SSC. The various functions required at a large laboratory are discussed; these include computer-based fire and security alarms and a cable television system, as well as computer networks connected to accelerator hardware components. A description is given of that hardware, of which much is Camac but with considerable computer backplane bus equipment also present. A large fraction of the controls hardware has access to high precision real-time clocks. Our various networks are introduced, with the physical layer being a combination of copper and more modern optic cables, with the primary intercomputer link being Token Ring. A description of the computers is presented - basically these consist of operators' consoles, host VAXs, and link driving front ends. The software effort is detailed, with emphasis on consoles and microprocessors where the majority of effort has been placed. Future plans for the system are presented briefly. 3 refs., 2 figs., 2 tabs

The planned replacement of a functioning control system on the CERN 28 GEV accelerator

International Nuclear Information System (INIS)

Carpenter, B.E.; Daneels, A.; Perriollat, F.

1979-01-01

The subject is discussed under the following headings: the accelerators (in the 28 GeV accelerator complex) and the old control system; goals of the new control system; constraints (involved in planning a replacement for the control system); a pilot project; major software issues in the system design; portability; parallelism; transition; conclusion. (U.K.)

Medical Proton Accelerator Project

International Nuclear Information System (INIS)

Comsan, M.N.H.

2008-01-01

A project for a medical proton accelerator for cancer treatment is outlined. The project is motivated by the need for a precise modality for cancer curing especially in children. Proton therapy is known by its superior radiation and biological effectiveness as compared to photon or electron therapy. With 26 proton and 3 heavy-ion therapy complexes operating worldwide only one (p) exists in South Africa, and none in south Asia and the Middle East. The accelerator of choice should provide protons with energy 75 MeV for eye treatment and 250 MeV for body treatment. Four treatment rooms are suggested: two with isocentric gantries, one with fixed beams and one for development. Passive scanning is recommended. The project can serve Middle East and North Africa with ∼ 400 million populations. The annual capacity of the project is estimated as 1,100 to be compared with expected radiation cases eligible for proton cancer treatment of not less than 200,000

The control system of CERN accelerators vacuum (current status and recent improvements)

International Nuclear Information System (INIS)

Gomes, P.; Antoniotti, F.; Blanchard, S.; Boccioli, M.; Girardot, G.; Vestergard, H.; Kopylov, L.; Mikheev, M.

2012-01-01

The vacuum control system of most of the CERN accelerators is based on Siemens PLCs and on PVSS SCADA. After the transition from the LHC commissioning phase to its regular operation, there has been a number of additions and improvements to the vacuum control system. They were driven by new technical requirements and by feedback from the accelerator operators and vacuum specialists. New control functions have been implemented in the PLCs; new tools have been developed for the SCADA, while its ergonomic and navigation have been enhanced. (authors)

Industrial influences on an accelerator control system

International Nuclear Information System (INIS)

Westervelt, R.

1992-01-01

Industrial applications of a control system package have extended from industrial research to process control. While the requirements of these applications have much in common with accelerator controls, there are always extensions, different emphases, and additional requirements. These often add to the applicability of the software in all fields and certainly keep the development team challenged. This paper discusses some of the influences that industrial applications such as power distribution monitoring, casting and rolling mills, and aircraft engine testing have on software originally designed for scientific research. We also discuss some of the differences in the software development process between development for in-house use and development for sales and industrial use. (Author) ref., fig

Optimization of Aero Engine Acceleration Control in Combat State Based on Genetic Algorithms

Science.gov (United States)

Li, Jie; Fan, Ding; Sreeram, Victor

2012-03-01

In order to drastically exploit the potential of the aero engine and improve acceleration performance in the combat state, an on-line optimized controller based on genetic algorithms is designed for an aero engine. For testing the validity of the presented control method, detailed joint simulation tests of the designed controller and the aero engine model are performed in the whole flight envelope. Simulation test results show that the presented control algorithm has characteristics of rapid convergence speed, high efficiency and can fully exploit the acceleration performance potential of the aero engine. Compared with the former controller, the designed on-line optimized controller (DOOC) can improve the security of the acceleration process and greatly enhance the aero engine thrust in the whole range of the flight envelope, the thrust increases an average of 8.1% in the randomly selected working states. The plane which adopts DOOC can acquire better fighting advantage in the combat state.

The new accelerator control system of GANIL

International Nuclear Information System (INIS)

Luong, T.T.; David, L.; Duneau, P.; De Saint Jores, P.; Lecorche, E.; Lemaitre, E.; Lermine, P.; Loyant, J.M.; Maugeais, C.; Regnault, F.; Roze, J.F.; Souf, A.; Ulrich, M.

1994-01-01

The new computer control system has operated the heavy ion accelerator GANIL from the beginning of 1993 and has reached a state of routine operation. It supersedes the obsolete initial system to cope with the harsh experimental conditions required by the very high intensity beams expected in the near future. Hardware and software implementations, as well as the human interface, are presented. Emphasis is placed on the three-layer distributed architecture adopted. An Ethernet local area network (LAN) links the basic components: a VAX/VMS cluster, XWINDOWS-interfaced operator consoles, VAXELN-driven CAMAC crate controllers and programmable logic controllers for the front end controls. Also the data management, through the INGRES relational database management system (RDBMS), as well as the operating software written in ADA, are described. The early experience with the new control system is reported and future developments discussed. ((orig.))

Applications of microprocessors in upgrading of accelerator controls

International Nuclear Information System (INIS)

Mallory, K.B.

1977-03-01

Experience at SLAC demonstrates that the criteria for selection and use of microprocessors in modifying an existing control system may differ from the criteria that apply during installation of the control system of a new accelerator. Considerations such as cost of individual projects, progressive installation without disruption of operations and training of on-board personnel can outweigh ''obvious'' goals such as standardization of hardware, uniformity of software, or even a rigid specification of link protocols with the main computer system

A mobile console for local access to accelerator control systems.

CERN Multimedia

1981-01-01

Microprocessors were installed as auxiliary crate controllers (ACCs) in the CAMAC interface of control systems for various accelerators. The same ACC was also at the hearth of a stand-alone system in the form of a mobile console. This was also used for local access to the control systems for tests and development work (Annual Report 1981, p. 80, Fig. 10).

Control of electron injection and acceleration in laser-wakefield accelerators

International Nuclear Information System (INIS)

Guillaume, E.

2015-01-01

Laser-plasma accelerators provide a promising compact alternative to conventional accelerators. Plasma waves with extremely strong electric fields are generated when a high intensity laser is focused into an underdense gas target. Electrons that are trapped in these laser-driven plasma waves can be accelerated up to energies of a few GeVs. Despite their great potential, laser-wakefield accelerators face some issues, regarding notably the stability and reproducibility of the beam when electrons are injected in the accelerating structure. In this manuscript, different techniques of electron injection are presented and compared, notably injection in a sharp density gradient and ionization injection. It is shown that combining these two methods allows for the generation of stable and tunable electron beams. We have also studied a way to manipulate the electron bunch in the phase-space in order to accelerate the bunch beyond the dephasing limit. Such a technique was used with quasi-monoenergetic electron beams to enhance their energy. Moreover, the origin of the evolution of the angular momentum of electrons observed experimentally was investigated. Finally, we demonstrated experimentally a new method - the laser-plasma lens - to strongly reduce the divergence of the electron beam. This laser-plasma lens consists of a second gas jet placed at the exit of the accelerator. The laser pulse drives a wakefield in this second jet whose focusing forces take advantage to reduce the divergence of the trailing electron bunch. A simple analytical model describing the principle is presented, underlining the major importance of the second jet length, density and distance from the first jet. Experimental demonstration of the laser-plasma lens shows a divergence reduction by a factor of 2.6 for electrons up to 300 MeV, in accordance with the model predictions

Fast digital feedback control systems for accelerator RF system using FPGA

International Nuclear Information System (INIS)

Bagduwal, Pritam Singh; Sharma, Dheeraj; Tiwari, Nitesh; Lad, M.; Hannurkar, P.R.

2012-01-01

Feedback control system plays important role for proper injection and acceleration of beam in particle accelerators by providing the required amplitude and phase stability of RF fields in accelerating structures. Advancement in the field of digital technology enables us to develop fast digital feedback control system for RF applications. Digital Low Level RF (LLRF) system offers the inherent advantages of Digital System like flexibility, adaptability, good repeatability and reduced long time drift errors compared to analog system. To implement the feedback control algorithm, I/Q control scheme is used. By properly sampling the down converted IF signal using fast ADC we get accurate feedback signal and also eliminates the need of two separate detectors for amplitude and phase detection. Controller is implemented in Vertex-4 FPGA. Codes for control algorithms which controls the amplitude and phase in all four quadrants with good accuracy are written in the VHDL. I/Q modulator works as common actuator for both amplitude and phase correction. Synchronization between RF, LO and ADC clock is indispensable and has been achieved by deriving the clock and LO signal from RF signal itself. Control system has been successfully tested in lab with phase and amplitude stability better then ±1% and ±1° respectively. High frequency RF signal is down converted to IF using the super heterodyne technique. Super heterodyne principal not only brings the RF signal to the Low IF frequency at which it can be easily processed but also enables us to use the same hardware and software for other RF frequencies with some minor modification. (author)

Field bus technology in accelerator control systems

International Nuclear Information System (INIS)

Tang Shuming

1999-01-01

Since eighties to now, the computer technology, network communication and ULSI technology have been developing rapidly. The level of control for industries and scientific experiments has been upgraded accordingly, so as to meet the increasing requirements for automation. The control systems become more complicated; the devices in control systems become more and more intelligent. However the cost of DCS (Distributed Control System) is quite expensive and the period of system integration is very long. More than ten measurement results for two methods defined in the world, in order to get inter operability of intelligent devices and reduce the costs. The author presents the development trend of fieldbuses briefly and describes the main performances of CAN, LONWORKS, WOLDFIP and PROFIBUS which are mainly used in the world today. The author proposes that the field bus technology will be introduced into the accelerator control systems in the country

The new accelerator control system of GANIL

International Nuclear Information System (INIS)

Luong, T.T.; David, L.; Duneau, P.; Saint Jores, P. De; Lecorche, E.; Lemaitre, E.; Lermine, P.; Loyant, J.M.; Maugeais, C.; Regnault, F.

1993-01-01

The new computer control system is conducting the heavy ion accelerator GANIL from the beginning of 1993 and has reached a state of routine operation. It was carried out to supersede the obsolete initial system and to cope with the harsh experimental conditions required by the very high intensity beams envisioned for the next future. Hardware and software implementations, as well as human interface, are presented. Emphasis is placed on the three-layer distributed architecture adopted. An ETHERNET local area network (LAN) links the basic components: a VAX/VMS cluster, XWINDOWS interfaced operator consoles, VAXELN driven CAMAC crate controllers and programmable logic controllers for front end controls. Also data management with the INGRES relational database management system (RDBMS), as well as operating software written in ADA language, are described. First experience with the new control system is reported. Finally, trend considerations are addressed. (author) 8 refs., 6 figs

Resonance Control for Future Linear Accelerators

Energy Technology Data Exchange (ETDEWEB)

Schappert, Warren [Fermilab

2017-05-01

Many of the next generation of particle accelerators (LCLS II, PIP II) are designed for relatively low beam loading. Low beam loading requirement means the cavities can operate with narrow bandwidths, minimizing capital and base operational costs of the RF power system. With such narrow bandwidths, however, cavity detuning from microphonics or dynamic Lorentz Force Detuning becomes a significant factor, and in some cases can significantly increase both the acquisition cost and the operational cost of the machine. In addition to the efforts to passive environmental detuning reduction (microphonics) active resonance control for the SRF cavities for next generation linear machine will be required. State of the art in the field of the SRF Cavity active resonance control and the results from the recent efforts at FNAL will be presented in this talk.

49 CFR 571.124 - Standard No. 124; Accelerator control systems.

Science.gov (United States)

2010-10-01

... and injuries resulting from engine overspeed caused by malfunctions in the accelerator control system..., respectively. S5. Requirements. The vehicle shall meet the following requirements when the engine is running...

Protecting Accelerator Control Systems in the Face of Sophisticated Cyber Attacks

International Nuclear Information System (INIS)

Hartman, Steven M.

2012-01-01

Cyber security for industrial control systems has received significant attention in the past two years. The news coverage of the Stuxnet attack, believed to be targeted at the control system for a uranium enrichment plant, brought the issue to the attention of news media and policy makers. This has led to increased scrutiny of control systems for critical infrastructure such as power generation and distribution, and industrial systems such as chemical plants and petroleum refineries. The past two years have also seen targeted network attacks aimed at corporate and government entities including US Department of Energy National Laboratories. Both of these developments have potential repercussions for the control systems of particle accelerators. The need to balance risks from potential attacks with the operational needs of an accelerator present a unique challenge for the system architecture and access model.

Towards full automation of accelerators through computer control

CERN Document Server

Gamble, J; Kemp, D; Keyser, R; Koutchouk, Jean-Pierre; Martucci, P P; Tausch, Lothar A; Vos, L

1980-01-01

The computer control system of the Intersecting Storage Rings (ISR) at CERN has always laid emphasis on two particular operational aspects, the first being the reproducibility of machine conditions and the second that of giving the operators the possibility to work in terms of machine parameters such as the tune. Already certain phases of the operation are optimized by the control system, whilst others are automated with a minimum of manual intervention. The authors describe this present control system with emphasis on the existing automated facilities and the features of the control system which make it possible. It then discusses the steps needed to completely automate the operational procedure of accelerators. (7 refs).

Towards full automation of accelerators through computer control

International Nuclear Information System (INIS)

Gamble, J.; Hemery, J.-Y.; Kemp, D.; Keyser, R.; Koutchouk, J.-P.; Martucci, P.; Tausch, L.; Vos, L.

1980-01-01

The computer control system of the Intersecting Storage Rings (ISR) at CERN has always laid emphasis on two particular operational aspects, the first being the reproducibility of machine conditions and the second that of giving the operators the possibility to work in terms of machine parameters such as the tune. Already certain phases of the operation are optimized by the control system, whilst others are automated with a minimum of manual intervention. The paper describes this present control system with emphasis on the existing automated facilities and the features of the control system which make it possible. It then discusses the steps needed to completely automate the operational procedure of accelerators. (Auth.)

Colliding pulse injection experiments in non-collinear geometry for controlled laser plasma wakefield acceleration of electrons

International Nuclear Information System (INIS)

Toth, Carl B.; Esarey, Eric H.; Geddes, Cameron G.R.; Leemans, Wim P.; Nakamura, Kei; Panasenko, Dmitriy; Schroeder, Carl B.; Bruhwiler, D.; Cary, J.R.

2007-01-01

An optical injection scheme for a laser-plasma based accelerator which employs a non-collinear counter-propagating laser beam to push background electrons in the focusing and acceleration phase via ponderomotive beat with the trailing part of the wakefield driver pulse is discussed. Preliminary experiments were performed using a drive beam of a 0 = 2.6 and colliding beam of a 1 = 0.8 both focused on the middle of a 200 mu m slit jet backed with 20 bar, which provided ∼ 260 mu m long gas plume. The enhancement in the total charge by the colliding pulse was observed with sharp dependence on the delay time of the colliding beam. Enhancement of the neutron yield was also measured, which suggests a generation of electrons above 10 MeV

Expanding Fiscal Policies for Global and National Tobacco Control ...

International Development Research Centre (IDRC) Digital Library (Canada)

This project aims to accelerate the adoption of effective fiscal policies for public ... control and/or innovative financing mechanisms in low- and middle-income ... from the health sciences, medicine, chemistry and engineering departments.

Modelling of control system architecture for next-generation accelerators

International Nuclear Information System (INIS)

Liu, Shi-Yao; Kurokawa, Shin-ichi

1990-01-01

Functional, hardware and software system architectures define the fundamental structure of control systems. Modelling is a protocol of system architecture used in system design. This paper reviews various modellings adopted in past ten years and suggests a new modelling for next generation accelerators. (author)

High performance current controller for particle accelerator magnets supply

DEFF Research Database (Denmark)

Maheshwari, Ram Krishan; Bidoggia, Benoit; Munk-Nielsen, Stig

2013-01-01

The electromagnets in modern particle accelerators require high performance power supply whose output is required to track the current reference with a very high accuracy (down to 50 ppm). This demands very high bandwidth controller design. A converter based on buck converter topology is used...

State-of-the-Art developments in accelerator controls at the APS

International Nuclear Information System (INIS)

Lenkszus, F.

1999-01-01

The performance requirements of the Advanced Photon Source (APS) challenge the control system in a number of areas. This paper will review a few applications of advanced technology in the control and monitoring of the APS. The application of digital signal processors (DSPs) and techniques will be discussed, both from the perspective of a large distributed multiprocessor system and from that of embedded systems. In particular, two embedded applications will be highlighted, a beam position monitor processor and a DSP-based power supply controller. Fast data distribution is often a requirement. The application of a high-speed network based on reflective memory will also be discussed in the context of the APS global orbit feedback system. Timing systems provide opportunities to apply technologies such as high-speed logic and fiber optics. Examples of the use of these technologies will also be included. Finally, every modern accelerator control system of any size requires networking. Features of the APS accelerator controls network will be discussed

Controlled Microwave Heating Accelerates Rolling Circle Amplification.

Directory of Open Access Journals (Sweden)

Takeo Yoshimura

Full Text Available Rolling circle amplification (RCA generates single-stranded DNAs or RNA, and the diverse applications of this isothermal technique range from the sensitive detection of nucleic acids to analysis of single nucleotide polymorphisms. Microwave chemistry is widely applied to increase reaction rate as well as product yield and purity. The objectives of the present research were to apply microwave heating to RCA and indicate factors that contribute to the microwave selective heating effect. The microwave reaction temperature was strictly controlled using a microwave applicator optimized for enzymatic-scale reactions. Here, we showed that microwave-assisted RCA reactions catalyzed by either of the four thermostable DNA polymerases were accelerated over 4-folds compared with conventional RCA. Furthermore, the temperatures of the individual buffer components were specifically influenced by microwave heating. We concluded that microwave heating accelerated isothermal RCA of DNA because of the differential heating mechanisms of microwaves on the temperatures of reaction components, although the overall reaction temperatures were the same.

Controlled Microwave Heating Accelerates Rolling Circle Amplification.

Science.gov (United States)

Yoshimura, Takeo; Suzuki, Takamasa; Mineki, Shigeru; Ohuchi, Shokichi

2015-01-01

Rolling circle amplification (RCA) generates single-stranded DNAs or RNA, and the diverse applications of this isothermal technique range from the sensitive detection of nucleic acids to analysis of single nucleotide polymorphisms. Microwave chemistry is widely applied to increase reaction rate as well as product yield and purity. The objectives of the present research were to apply microwave heating to RCA and indicate factors that contribute to the microwave selective heating effect. The microwave reaction temperature was strictly controlled using a microwave applicator optimized for enzymatic-scale reactions. Here, we showed that microwave-assisted RCA reactions catalyzed by either of the four thermostable DNA polymerases were accelerated over 4-folds compared with conventional RCA. Furthermore, the temperatures of the individual buffer components were specifically influenced by microwave heating. We concluded that microwave heating accelerated isothermal RCA of DNA because of the differential heating mechanisms of microwaves on the temperatures of reaction components, although the overall reaction temperatures were the same.

A Framework for a General Purpose Intelligent Control System for Particle Accelerators. Phase II Final Report

International Nuclear Information System (INIS)

Westervelt, Robert; Klein, William; Kroupa, Michael; Olsson, Eric; Rothrock, Rick

1999-01-01

Vista Control Systems, Inc. has developed a portable system for intelligent accelerator control. The design is general in scope and is thus configurable to a wide range of accelerator facilities and control problems. The control system employs a multi-layer organization in which knowledge-based decision making is used to dynamically configure lower level optimization and control algorithms

Designing an object-oriented scheme for accelerator equipment control

International Nuclear Information System (INIS)

Trofimov, N.N.

1994-01-01

The object-oriented analysis (OOA) and design (OOD) formalisms developed by Project Technology Inc. is presented in this report. The method was originated in 1979 with the analysis phase of a large real-time project at Lawrence Berkeley Laboratory and since that time has been used in several large-scale industrial projects. It is supported by the Teamwork CASE package from Cadre Technologies Inc. For introducing basic concepts and definitions of the OOA/OOD, a typical accelerator device example: remotely controllable power supply which is used to power magnets in an accelerator beam transfer line is used through out this report. 18 refs., 18 figs

Design & simulation of a 800 kV dynamitron accelerator by CST studio

Directory of Open Access Journals (Sweden)

A M Aghayan

2015-09-01

Full Text Available Nowadays, middle energy electrostatic accelerators in industries are widely used due to their high efficiency and low cost compared with other types of accelerators. In this paper, the importance and applications of electrostatic accelerators with 800 keV energy are studied. Design and simulation of capacitive coupling of a dynamitron accelerator is proposed. Furthermore, accelerating tube are designed and simulated by means of CST Suit Studio

Accelerated spike resampling for accurate multiple testing controls.

Science.gov (United States)

Harrison, Matthew T

2013-02-01

Controlling for multiple hypothesis tests using standard spike resampling techniques often requires prohibitive amounts of computation. Importance sampling techniques can be used to accelerate the computation. The general theory is presented, along with specific examples for testing differences across conditions using permutation tests and for testing pairwise synchrony and precise lagged-correlation between many simultaneously recorded spike trains using interval jitter.

Evolution of the Argonne Tandem Linear Accelerator System (ATLAS) control system

International Nuclear Information System (INIS)

Power, M.; Munson, F.

2012-01-01

Given that the Argonne Tandem Linear Accelerator System (ATLAS) recently celebrated its 25. anniversary, this paper will explore the past, present, and future of the ATLAS Control System, and how it has evolved along with the accelerator and control system technology. ATLAS as we know it today, originated with a Tandem Van de Graff in the sixties. With the addition of the Booster section in the late seventies, came the first computerized control. ATLAS itself was placed into service on June 25, 1985, and was the world's first superconducting linear accelerator for ions. Since its dedication as a National User Facility, more than a thousand experiments by more than 2,000 users worldwide, have taken advantage of the unique capabilities it provides. Today, ATLAS continues to be a user facility for physicists who study the particles that form the heart of atoms. Its most recent addition, CARIBU (Californium Rare Isotope Breeder Upgrade), creates special beams that feed into ATLAS. ATLAS is similar to a living organism, changing and responding to new technological challenges and research needs. As it continues to evolve, so does the control system: from the original days using a DEC PDP-11/34 computer and two CAMAC crates, to a DEC Alpha computer running Vsystem software and more than twenty CAMAC crates, to distributed computers and VME systems. Future upgrades are also in the planning stages that will continue to evolve the control system. (authors)

The graphics software of the Saclay Linear Accelerator control system

International Nuclear Information System (INIS)

Gournay, J.F.

1988-01-01

The graphics software used for the control of the Saclay Linear Accelerator is described. The specific requirements that such a software must have in this environment are outlined and some typical applications are presented. (orig.)

Asynchronous data change notification between database server and accelerator controls system

International Nuclear Information System (INIS)

Fu, W.; Morris, J.; Nemesure, S.

2011-01-01

Database data change notification (DCN) is a commonly used feature. Not all database management systems (DBMS) provide an explicit DCN mechanism. Even for those DBMS's which support DCN (such as Oracle and MS SQL server), some server side and/or client side programming may be required to make the DCN system work. This makes the setup of DCN between database server and interested clients tedious and time consuming. In accelerator control systems, there are many well established software client/server architectures (such as CDEV, EPICS, and ADO) that can be used to implement data reflection servers that transfer data asynchronously to any client using the standard SET/GET API. This paper describes a method for using such a data reflection server to set up asynchronous DCN (ADCN) between a DBMS and clients. This method works well for all DBMS systems which provide database trigger functionality. Asynchronous data change notification (ADCN) between database server and clients can be realized by combining the use of a database trigger mechanism, which is supported by major DBMS systems, with server processes that use client/server software architectures that are familiar in the accelerator controls community (such as EPICS, CDEV or ADO). This approach makes the ADCN system easy to set up and integrate into an accelerator controls system. Several ADCN systems have been set up and used in the RHIC-AGS controls system.

Accelerator mass analysis at tandem accelerator in Kyoto University

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Masanobu; Tazawa, Yuji; Matsumoto, Hiroshi; Hirose, Masanori [Kyoto Univ. (Japan). Faculty of Science; Ogino, Koya; Kohno, Masuchika; Funaba, Hiroyuki

1996-12-01

Tandem accelerator in Science Faculty, Kyoto University was renewed from 5 MV in the highest terminal voltage of Van de Graaff to 8 MV of Peletron in 1992. And, AMS effective for cosmic ray, dating, environment measurement and so forth is determined to a column of collaborative studies by universities and institutes in Japan. On this renewal, because of using high energy beam transportation of the present tandem accelerator, super high sensitivity measurement of long half-life radioactive isotopes of heavy elements such as {sup 36}Cl, {sup 41}Ca, {sup 129}I and so forth is aimed, although having some limitations due to small magnet. The accelerator is active in characteristics of the middle size tandem accelerator, and developing {sup 14}C measurement for its standard technology, as aiming at {sup 36}Cl measurement, at first. As a result, in this tandem accelerator stable and high beam transmittance could be obtained by adding a slit at negative ion source to make emittance of incident beam smaller. {sup 14}C/{sup 12}C ratio of Modan`s sample obtained by graphitizing NBS oxalic acid and Ded`s sample consisting of mineral graphite produced in Sri Lanka are measured to confirm better reproductivity of this system. Future development of successive incident method is planned to test actual carbon samples. (G.K.)

An artificial intelligence approach to accelerator control systems

International Nuclear Information System (INIS)

Schultz, D.E.; Hurd, J.W.; Brown, S.K.

1987-01-01

An experiment was recently started at LAMPF to evaluate the power and limitations of using artificial intelligence techniques to solve problems in accelerator control and operation. A knowledge base was developed to describe the characteristics and the relationships of the first 30 devices in the LAMPF H+ beam line. Each device was categorized and pertinent attributes for each category defined. Specific values were assigned in the knowledge base to represent each actual device. Relationships between devices are modeled using the artificial intelligence techniques of rules, active values, and object-oriented methods. This symbolic model, built using the Knowledge Engineering Environment (KEE) system, provides a framework for analyzing faults, tutoring trainee operators, and offering suggestions to assist in beam tuning. Based on information provided by the domain expert responsible for tuning this portion of the beam line, additional rules were written to describe how he tunes, how he analyzes what is actually happening, and how he deals with failures. Initial results have shown that artificial intelligence techniques can be a useful adjunct to traditional methods of numerical simulation. Successful and efficient operation of future accelerators may depend on the proper merging of symbolic reasoning and conventional numerical control algorithms

Neural networks and orbit control in accelerators

International Nuclear Information System (INIS)

Bozoki, E.; Friedman, A.

1994-01-01

An overview of the architecture, workings and training of Neural Networks is given. We stress the aspects which are important for the use of Neural Networks for orbit control in accelerators and storage rings, especially its ability to cope with the nonlinear behavior of the orbit response to 'kicks' and the slow drift in the orbit response during long-term operation. Results obtained for the two NSLS storage rings with several network architectures and various training methods for each architecture are given

The impact of new accelerator control software on LEP performance

International Nuclear Information System (INIS)

Bailey, R.; Belk, A.; Collier, P.; Lamont, M.; Rigk, G. de; Tarrant, M.

1993-01-01

After the first year of running LEP, it became apparent that a new generation of application software would be required for efficient long term exploitation of the accelerator. In response to this need, a suite of accelerator control software has been developed, which is new both in style and functionality. During 1992 this software has been extensively used for driving LEP in many different operational modes, which include several different optics, polarisation runs at different energies and 8 bunch operation with Pretzels. The software has performed well and has undoubtedly enhanced the efficiency of accelerator operations. In particular the turnaround time has been significantly reduced, giving an increase of around 20% in the integrated luminosity for the year. Furthermore the software has made the accelerator accessible to less experienced operators. After outlining the development strategy, the overall functionality and performance of the software is discussed, with particular emphasis on improvements in operating efficiency. Some evaluation of the performance and reliability of ORACLE as an on-line database is also given

External radiation exposure control system in accelerator facilities

International Nuclear Information System (INIS)

Ogawa, Tatsuhiko; Iimoto, Takeshi; Kosako, Toshiso

2011-01-01

The external exposure control systems in KEK and CERN are discussed to find out good practices and unreasonableness of radiation control in accelerator facilities, which plays an important role in optimizing national and/or site specific radiological regulations, referring to relevant ICRP publications. Personal dose limits and radiation area classifications were analyzed and their reasonableness were explored. Good example of supervised areas, area classification based on realistic assumptions on working time etc are found. On the other hand, unreasonable systems, that are often attributed to the national regulation or ideas presented in the old publications are also found. (author)

Experimental study of liquid-metal target designs of accelerating-controlled systems

International Nuclear Information System (INIS)

Iarmonov, Mikhail; Makhov, Kirill; Novozhilova, Olga; Meluzov, A.G.; Beznosov, A.V.

2011-01-01

Models of a liquid-metal target of an accelerator-controlled system have been experimentally studied at the Nizhny Novgorod State Technical University to develop an optimal design of the flow part of the target. The main explored variants of liquid-metal targets are: Design with a diaphragm (firm-and-impervious plug) mounted on the pipe tap of particle transport from the accelerator cavity to the working cavity of the liquid-metal target. Design without a diaphragm on the pipe tab of particle transport from the accelerator. The study was carried out in a high-temperature liquid-metal test bench under the conditions close to full-scale ones: the temperature of the eutectic lead-bismuth alloy was 260degC - 400degC, the coolant mass flow was 5-80 t/h, and the rarefaction in the gas cavity was 10 5 Pa, the coefficient of geometric similarity equal to 1. The experimental studies of hydrodynamic characteristics of flow parts in the designs of targets under full-scale conditions indicated high efficiency of a target in triggering, operating, and deactivating modes. Research and technology instructions for designs of the flow part of the liquid-metal target, the target design as a whole, and the target circuit of accelerator-controlled systems were formulated as a result of the studies. (author)

Accelerator research on MBE-4, an experimental multi-beam induction linac

International Nuclear Information System (INIS)

Meuth, H.; Fessenden, T.J.; Keefe, D.; Warwick, A.I.

1988-06-01

The multiple beam accelerator MBE-4 is a device for research toward a heavy ion driver for inertial confinement fusion, based on the induction linac concept. Its main goal is proof of the principle of current amplification by acceleration and controlled self-similar beam pulse compression. Into the 16-m long device four beams, each with an initial current of 10 mA are injected from a Marx-driven diode at 200 keV. The current amplification is up to nine-fold, with a final beam energy of about 800 keV in the middle of the bunch. Now that all the apparatus' accelerator sections have been completed, installed and aligned, and its unaccelerated transport properties have been studied, our experimental research has reached the crucial phase of implementing appropriate accelerator schedules that approximate self-similar current-pulse compression. These schedules are established through a close interplay of computations using a one-dimensional simulation code and a manual empirical tuning procedure. In a first approach, with a rather vigorous schedule that uses most of the accelerator modules to their voltage limits, we have determined the limits of our capability for controlled pulse compression, mainly due to waveform shaping of the driving pulse-forming networks. We shall report on these results. In the future, we will also aim for gentler schedules that would model more closely an inertial confinement fusion scenario. 8 refs., 11 figs., 1 tab

Evolution and development of the Oak Ridge 25URC tandem accelerator control system

International Nuclear Information System (INIS)

Juras, R.C.; Ziegler, N.F.; Meigs, M.J.; McPherson, R.L.; Hoglund, D.E.; Biggerstaff, J.A.

1987-01-01

Since acceptance of the 25URC accelerator in 1982, we have continued to develop and improve both the accelerator control system and associated software. In this paper, we describe these improvements and also discuss how our experience with the present system would influence the architecture and design of future, similar systems

Power supplies in 14 UD pelletron accelerator and its control (Paper No. CP 12)

International Nuclear Information System (INIS)

Vaze, M.Y.; Bhalerao, P.J.; Tambvekar, V.V.

1990-01-01

14UD Pelletron is a 14 million volt tandem heavy ion accelerator. For generation of the accelerating voltage, heavy ion beams and transporting the beam through low energy injector systems, accelerator, high energy system, analysing magnets and finally upto the target different types of types of D.C. power supplies with varying capacity and specifications are used in this accelerator. Broadly these power supplies can be classified in three different types: (1)D.C. high voltage low current voltage regulated supplies, (2)Low voltage high current current regulated high precision D.C. power supplies, and (3)Medium power current regulated D.C. power supplies. These power supplies are described and systems where they are used are mentioned. They are interfaced with CAMAC module and are controlled and monitored remotely from the control room through the serial highway link. (author). 2 figs

Accelerated aging and controlled deterioration for the determination of the physiological potential of onion seeds

Directory of Open Access Journals (Sweden)

Rodo Angelica Brod

2003-01-01

Full Text Available International research on vegetable seed vigor is not at the same level attained for grain crops species. This study was conducted to identify reliable procedures for the accelerated aging and controlled deterioration tests to rank onion (Allium cepa L. seed lots according to their physiological potential. Six seed lots of the cultivars Aurora and Petroline were evaluated in the laboratory for germination, first count, seedling vigor classification, traditional and saturated salt accelerated aging (41masculineC / 48 and 72 h, controlled deterioration (24% of water / 45masculineC / 24 h and seedling emergence tests. Seed moisture content after the saturated salt accelerated aging test was lower and uniform, which is considered an important advantage in comparison to the traditional procedure. The saturated salt accelerated aging (41masculineC / 48 and 72 h and controlled deterioration (moisture content adjusted to 24% / 45masculineC / 24 h tests were the best procedures to assess the physiological potential of onion seeds, and are indicated for use in quality control programs.

An Integrated Enterprise Accelerator Database for the SLC Control System

International Nuclear Information System (INIS)

2002-01-01

Since its inception in the early 1980's, the SLC Control System has been driven by a highly structured memory-resident real-time database. While efficient, its rigid structure and file-based sources makes it difficult to maintain and extract relevant information. The goal of transforming the sources for this database into a relational form is to enable it to be part of a Control System Enterprise Database that is an integrated central repository for SLC accelerator device and Control System data with links to other associated databases. We have taken the concepts developed for the NLC Enterprise Database and used them to create and load a relational model of the online SLC Control System database. This database contains data and structure to allow querying and reporting on beamline devices, their associations and parameters. In the future this will be extended to allow generation of EPICS and SLC database files, setup of applications and links to other databases such as accelerator maintenance, archive data, financial and personnel records, cabling information, documentation etc. The database is implemented using Oracle 8i. In the short term it will be updated daily in batch from the online SLC database. In the longer term, it will serve as the primary source for Control System static data, an R and D platform for the NLC, and contribute to SLC Control System operations

Centralized digital control of accelerators

International Nuclear Information System (INIS)

Melen, R.E.

1984-01-01

Upon careful examination of the architecture of SLAC's computer control systems, it becomes evident that the distribution of the systems' intelligence generally falls into tree-like layers. The first layer typically consists of a central computer complex incorporating one or more relatively large and powerful processors. The more modern systems use state-of-the-art 32-bit processors with several megabytes of RAM and several hundreds of megabytes of disk memory. Further, they support extensive user-friendly operating systems and program development facilities. The second layer typically consists of several smaller processors which are downloaded from the central complex and whose primary task is to provide data acquisition and distribution. The more modern systems are 16-bit processors with several hundred kilobytes of RAM and no disk memory. The third layer typically consists of several tens or hundreds of micro-processors, each dedicated to a single device. The micro-processors for these ''dedicated intelligent controllers'' are small and inexpensive and typically require less than 32 kilobytes of RAM or EPROM memory. Their hardware may be general purpose in nature or may be built into the architecture of the device itself. Figure 5 illustrates several of the relevant features of each of these layers. This paper serves to illustrate that SLAC is commited to the centralized digital control of its accelerators

Transmission Control of Transport and Technological Cars in Acceleration Mode

Directory of Open Access Journals (Sweden)

B. I. Plujnikov

2015-01-01

Full Text Available In most structures a transmission of the transport-technological machine (TTM is controlled by automatic systems. In their creating it is necessary to specify the appropriate parameters and algorithms. In the total balance of the machine run time the acceleration mode is the most important. Therefore, an algorithm of the transmission gear ratio change during acceleration largely provides desirable rating of machines.It is known that the process of acceleration is estimated by its dynamic quality and fuel economy. To reach the best rating of both simultaneously is impossible. Therefore, as the criteria of estimate, were chosen the time and fuel consumption during acceleration to a fixed speed value.From a mathematical point of view, these criteria represent the sum of integrals, each of which defines the time or the fuel consumption during acceleration with a certain transmission gear ratio. The problem is formulated as follows: to determine the speed values of the TTM at the moments when the transmission gear ratio is changed providing the minimum values during fixed fuel supply for the estimate criteria. The latter condition in a certain way limits the task, but in explicit form there is no this control action in the dependence data.Given the variety of possible design options for the TTM, the solution is given by a specific example that simplifies the mathematics and makes it easier to understand the results obtained. As a TTM, is considered a passenger car with petrol engine and automatic transmission, which includes a hydrodynamic transformer and three-speed gearbox.A chosen way of solving the problem involves using the theory of ordinary maxima and minima, which allows finding the unknown values of independent variables. The expressions of sub-integral functions are in explicit form obtained and studied for meeting the necessary and sufficient conditions for existence of the extreme point. The result was a proof that in the case of

Operating experience with a new accelerator control system based upon microprocessors

Energy Technology Data Exchange (ETDEWEB)

Magyary, S.; Lancaster, H.; Selph, F.; Fahmie, M.; Timossi, C.; Glatz, J.; Ritchie, A.; Hinkson, J.; Benjegerdes, R.; Brodzik, D.

1981-03-01

This paper describes the design and operating experience with a high performance control system tailored to the requirements of the SuperHILAC accelerator. A large number (20) of the latest 16-bit microcomputer boards are used in a parallel-distributed manner to get a high system bandwidth. Because of the high bandwidth, software costs and complexity are significantly reduced. The system by its very nature and design is easily upgraded and repaired. Dynamically assigned and labeled knobs, together with touch-panels, allow a flexible and efficient operator interface. An X-Y vector graphics system provides for display and labeling of real-time signals as well as general plotting functions. This control system allows attachment of a powerful auxiliary computer for scientific processing with access to accelerator parameters.

Electron acceleration by surface plasma waves in double metal surface structure

Science.gov (United States)

Liu, C. S.; Kumar, Gagan; Singh, D. B.; Tripathi, V. K.

2007-12-01

Two parallel metal sheets, separated by a vacuum region, support a surface plasma wave whose amplitude is maximum on the two parallel interfaces and minimum in the middle. This mode can be excited by a laser using a glass prism. An electron beam launched into the middle region experiences a longitudinal ponderomotive force due to the surface plasma wave and gets accelerated to velocities of the order of phase velocity of the surface wave. The scheme is viable to achieve beams of tens of keV energy. In the case of a surface plasma wave excited on a single metal-vacuum interface, the field gradient normal to the interface pushes the electrons away from the high field region, limiting the acceleration process. The acceleration energy thus achieved is in agreement with the experimental observations.

Controlling Behaviors in Middle School Youth's Dating Relationships: Reactions and Help-Seeking Behaviors

Science.gov (United States)

Elias-Lambert, Nada; Black, Beverly M.; Chigbu, Kingsley U.

2014-01-01

This exploratory study examined middle school students' (N = 380) help-seeking behaviors and other reactions to controlling behaviors in their dating relationships. Over three-fourths of the participants perpetrated and were victimized by controlling behaviors in their dating relationships. Youth used emotional/verbal and dominance/isolation forms…

Particle accelerator control and data acquisition in the context of VAX/VMS

International Nuclear Information System (INIS)

Schaller, S.C.; Corley, J.K.

1983-01-01

The Los Alamos Meson Physics Facility (LAMPF) Control System monitors and controls a linear accelerator through more than 10,000 widely disparate I/O devices. The heart of the Control System software is the Data System, which provides a uniform application program interface based on symbolic device names. In many ways the Data System parallels the VAX/VMS Record Management Services (RMS) in its needs for asynchronous operations, protection, and locks for multiprocess interactions. Since the accelerator control hardware is continually changing, it is important that privileged code be kept to a minimum or be testable in a non-privileged environment. This paper describes the LAMPF Data System design including the use of VAX/VMS user written system services (both kernel and supervisor mode), a user supplied image rundown routine, the VAX/VMS lock manager, and a large (3.5 Mbyte) protected global section

Distribution of computer functionality for accelerator control at the Brookhaven AGS

International Nuclear Information System (INIS)

Stevens, A.; Clifford, T.; Frankel, R.

1985-01-01

A set of physical and functional system components and their interconnection protocols have been established for all controls work at the AGS. Portions of these designs were tested as part of enhanced operation of the AGS as a source of polarized protons and additional segments will be implemented during the continuing construction efforts which are adding heavy ion capability to our facility. Included in our efforts are the following computer and control system elements: a broad band local area network, which embodies MODEMS; transmission systems and branch interface units; a hierarchical layer, which performs certain data base and watchdog/alarm functions; a group of work station processors (Apollo's) which perform the function of traditional minicomputer host(s) and a layer, which provides both real time control and standardization functions for accelerator devices and instrumentation. Data base and other accelerator functionality is assigned to the most correct level within our network for both real time performance, long-term utility, and orderly growth

Accelerating Mathematics Achievement Using Heterogeneous Grouping

Science.gov (United States)

Burris, Carol Corbett; Heubert, Jay P.; Levin, Henry M.

2006-01-01

This longitudinal study examined the effects of providing an accelerated mathematics curriculum in heterogeneously grouped middle school classes in a diverse suburban school district. A quasi-experimental cohort design was used to evaluate subsequent completion of advanced high school math courses as well as academic achievement. Results showed…

An accelerator controls network designed for reliability and flexibility

International Nuclear Information System (INIS)

McDowell, W. P.; Sidorowicz, K. V.

1997-01-01

The APS accelerator control system is a typical modern system based on the standard control system model, which consists of operator interfaces to a network and computer-controlled interfaces to hardware. The network provides a generalized communication path between the host computers, operator workstations, input/output crates, and other hardware that comprise the control system. The network is an integral part of all modern control systems and network performance will determine many characteristics of a control system. This paper describes the methods used to provide redundancy for various network system components as well as methods used to provide comprehensive monitoring of this network. The effect of archiving tens of thousands of data points on a regular basis and the effect on the controls network will be discussed. Metrics are provided on the performance of the system under various conditions

Status and Future Developments in Large Accelerator Control Systems

International Nuclear Information System (INIS)

Karen S. White

2006-01-01

Over the years, accelerator control systems have evolved from small hardwired systems to complex computer controlled systems with many types of graphical user interfaces and electronic data processing. Today's control systems often include multiple software layers, hundreds of distributed processors, and hundreds of thousands of lines of code. While it is clear that the next generation of accelerators will require much bigger control systems, they will also need better systems. Advances in technology will be needed to ensure the network bandwidth and CPU power can provide reasonable update rates and support the requisite timing systems. Beyond the scaling problem, next generation systems face additional challenges due to growing cyber security threats and the likelihood that some degree of remote development and operation will be required. With a large number of components, the need for high reliability increases and commercial solutions can play a key role towards this goal. Future control systems will operate more complex machines and need to present a well integrated, interoperable set of tools with a high degree of automation. Consistency of data presentation and exception handling will contribute to efficient operations. From the development perspective, engineers will need to provide integrated data management in the beginning of the project and build adaptive software components around a central data repository. This will make the system maintainable and ensure consistency throughout the inevitable changes during the machine lifetime. Additionally, such a large project will require professional project management and disciplined use of well-defined engineering processes. Distributed project teams will make the use of standards, formal requirements and design and configuration control vital. Success in building the control system of the future may hinge on how well we integrate commercial components and learn from best practices used in other industries

Radiation control at the Continuous Electron Beam Accelerator Facility (CEBAF), a new high power CW electron accelerator installation

International Nuclear Information System (INIS)

Stapleton, G.B.; Thomas, R.H.

1989-01-01

A description is given of the design goals and radiation control measures, for a new 4 GeV, 1 MW electron accelerator under construction in the USA. The paper illustrates the importance of cooperation between designers and regulators. 15 refs., 1 fig., 3 tabs

FEATURES OF CONTROLLING ELECTROPNEUMATIC VALVES OF ACTUATOR TO CONTROL ITS CLUTCH WITH ACCELERATION VALVE

Directory of Open Access Journals (Sweden)

O. A. Yaryta

2018-01-01

Full Text Available The article deals with one of the ways to control an actuator of the automated clutch control system. The aim is to design control of the electropneumatic actuator, to control its coupling with the acceleration valve on the basis of experimental research as well as to provide rational parameters of the automated clutch control system for the robotic transmission. The feature of the system is an acceleration valve in the design of the electropneumatic actuator to control the clutch. New links demand to adjust the way to control the actuator. The connection of Pulse-Width Modulation (PWM with single power supply pulses to control electropneumatic valves is substantiated. The quantitative characteristics of single control pulses and PWM ones are determined. The error of operation accuracy for various ways of the control of the electropneumatic actuator to control the clutch of the robotic transmission is determined. Obtained separate PWM area is designed to suppress the initial hysteresis when the rod of the clutch actuator is moved. An algorithm for the operation of a clutch control system is proposed, taking into account the use of two modes of operation of solenoid valves. A graphical interpretation of the clutch control algorithm is presented, which gives an idea of the location of the constant signal feeding zones to the solenoid valve, as well as the operation areas of the solenoid valve in PWM mode. The control algorithm of the clutch booster provides a mode of guaranteed absence of excess pressure in the pneumatic cylinder after releasing the clutch pedal, provided that two normally closed solenoid valves are used. This configuration of the electro-pneumatic clutch control system allows the use of an emergency clutch release system in case of voltage absence. The reference algorithm for filtering the array of data coming from the feedback sensor, as well as the numerical values of the delay caused by the presence of a filter, are given.

Engineered and Administrative Safety Systems for the Control of Prompt Radiation Hazards at Accelerator Facilities

International Nuclear Information System (INIS)

Liu, James C.; SLAC; Vylet, Vashek; Walker, Lawrence S.

2007-01-01

The ANSI N43.1 Standard, currently in revision (ANSI 2007), sets forth the requirements for accelerator facilities to provide adequate protection for the workers, the public and the environment from the hazards of ionizing radiation produced during and from accelerator operations. The Standard also recommends good practices that, when followed, provide a level of radiation protection consistent with those established for the accelerator communities. The N43.1 Standard is suitable for all accelerator facilities (using electron, positron, proton, or ion particle beams) capable of producing radiation, subject to federal or state regulations. The requirements (see word 'shall') and recommended practices (see word 'should') are prescribed in a graded approach that are commensurate with the complexity and hazard levels of the accelerator facility. Chapters 4, 5 and 6 of the N43.1 Standard address specially the Radiation Safety System (RSS), both engineered and administrative systems, to mitigate and control the prompt radiation hazards from accelerator operations. The RSS includes the Access Control System (ACS) and Radiation Control System (RCS). The main requirements and recommendations of the N43.1 Standard regarding the management, technical and operational aspects of the RSS are described and condensed in this report. Clearly some aspects of the RSS policies and practices at different facilities may differ in order to meet the practical needs for field implementation. A previous report (Liu et al. 2001a), which reviews and summarizes the RSS at five North American high-energy accelerator facilities, as well as the RSS references for the 5 labs (Drozdoff 2001; Gallegos 1996; Ipe and Liu 1992; Liu 1999; Liu 2001b; Rokni 1996; TJNAF 1994; Yotam et al. 1991), can be consulted for the actual RSS implementation at various laboratories. A comprehensive report describing the RSS at the Stanford Linear Accelerator Center (SLAC 2006) can also serve as a reference

Experimental control of the beam properties of laser-accelerated protons and carbon ions

Energy Technology Data Exchange (ETDEWEB)

Amin, Munib

2008-12-15

The laser generation of energetic high quality beams of protons and heavier ions has opened up the door to a plethora of applications. These beams are usually generated by the interaction of a short pulse high power laser with a thin metal foil target. They could already be applied to probe transient phenomena in plasmas and to produce warm dense matter by isochoric heating. Other applications such as the production of radioisotopes and tumour radiotherapy need further research to be put into practice. To meet the requirements of each application, the properties of the laser-accelerated particle beams have to be controlled precisely. In this thesis, experimental means to control the beam properties of laser-accelerated protons and carbon ions are investigated. The production and control of proton and carbon ion beams is studied using advanced ion source designs: Experiments concerning mass-limited (i.e. small and isolated) targets are conducted. These targets have the potential to increase both the number and the energy of laser-accelerated protons. Therefore, the influence of the size of a plane foil target on proton beam properties is measured. Furthermore, carbon ion sources are investigated. Carbon ions are of particular interest in the production of warm dense matter and in cancer radiotherapy. The possibility to focus carbon ion beams is investigated and a simple method for the production of quasi-monoenergetic carbon ion beams is presented. This thesis also provides an insight into the physical processes connected to the production and the control of laser-accelerated ions. For this purpose, laser-accelerated protons are employed to probe plasma phenomena on laser-irradiated targets. Electric fields evolving on the surface of laser-irradiated metal foils and hollow metal foil cylinders are investigated. Since these fields can be used to displace, collimate or focus proton beams, understanding their temporal and spatial evolution is crucial for the design of

Experimental control of the beam properties of laser-accelerated protons and carbon ions

International Nuclear Information System (INIS)

Amin, Munib

2008-12-01

The laser generation of energetic high quality beams of protons and heavier ions has opened up the door to a plethora of applications. These beams are usually generated by the interaction of a short pulse high power laser with a thin metal foil target. They could already be applied to probe transient phenomena in plasmas and to produce warm dense matter by isochoric heating. Other applications such as the production of radioisotopes and tumour radiotherapy need further research to be put into practice. To meet the requirements of each application, the properties of the laser-accelerated particle beams have to be controlled precisely. In this thesis, experimental means to control the beam properties of laser-accelerated protons and carbon ions are investigated. The production and control of proton and carbon ion beams is studied using advanced ion source designs: Experiments concerning mass-limited (i.e. small and isolated) targets are conducted. These targets have the potential to increase both the number and the energy of laser-accelerated protons. Therefore, the influence of the size of a plane foil target on proton beam properties is measured. Furthermore, carbon ion sources are investigated. Carbon ions are of particular interest in the production of warm dense matter and in cancer radiotherapy. The possibility to focus carbon ion beams is investigated and a simple method for the production of quasi-monoenergetic carbon ion beams is presented. This thesis also provides an insight into the physical processes connected to the production and the control of laser-accelerated ions. For this purpose, laser-accelerated protons are employed to probe plasma phenomena on laser-irradiated targets. Electric fields evolving on the surface of laser-irradiated metal foils and hollow metal foil cylinders are investigated. Since these fields can be used to displace, collimate or focus proton beams, understanding their temporal and spatial evolution is crucial for the design of

High intensity proton accelerator controls network upgrade

International Nuclear Information System (INIS)

Krempaska, R.; Bertrand, A.; Lendzian, F.; Lutz, H.

2012-01-01

The High Intensity Proton Accelerator (HIPA) control system network is spread through a vast area in PSI and it was grown historically in an unorganized way. The miscellaneous network hardware infrastructure and the lack of the documentation and components overview could no longer guarantee the reliability of the control system and the facility operation. Therefore, a new network, based on modern network topology, PSI standard hardware with monitoring and detailed documentation and overview was needed. The number of active components has been reduced from 25 to 9 Cisco Catalyst 24- or 48-port switches. They are the same type as other PSI switches, thus a replacement emergency stock is not an issue anymore. We would like to present how we successfully achieved this goal and the advantages of the clean and well documented network infrastructure. (authors)

HEPTech Academia – Industry Matching Event on Control Systems for Accelerators and Detectors

CERN Multimedia

Anastasios Charitonidis (FP/KT), on behalf of the organizing committee

2013-01-01

The HEPTech AIME (Academia – Industry Matching Event) on Controls for accelerators and detectors will take place from 2 to 3 December in Athens, Greece.   The HEPTech network invites you to Demokritos NCSR to participate in an event that aims to bring together Academia and Industry to share ideas and potential applications of Controls Technology. The event will provide an overview of current Controls Systems for large scale projects including the LHC, the CMS and ATLAS detectors, medical accelerator facilities and contributions from companies active in these fields. CERN Computer Centre. The programme will also address some of the challenges faced by future High Energy Physics projects in the controls area and provide a glimpse into the future requirements of research infrastructures such as the European Spallation Source (ESS), and the Extreme Light Infrastructure (ELI), while exploring different possible approaches to the commercialisation of controls technology. The event ...

Architectures and Algorithms for Control and Diagnostics of Coupled-Bunch Instabilities in Circular Accelerators

Energy Technology Data Exchange (ETDEWEB)

Teytelman, Dmitry

2003-07-08

Modern light sources and circular colliders employ large numbers of high-intensity particle bunches in order to achieve high luminosity. The electromagnetic coupling of bunches via resonant structures causes coherent instabilities at high beam currents. Achieving high luminosity requires the control of such unstable motion. Feedback control is challenging due to wideband nature of the problem with up to 250 MHz bandwidths required. This thesis presents digital signal processing architectures and diagnostic techniques for control of longitudinal and transverse coupled-bunch instabilities. Diagnostic capabilities integrated into the feedback system allow one to perform fast transient measurements of unstable dynamics by perturbing the beam from the controlled state via feedback and recording the time-domain response. Such measurements enable one to thoroughly characterize plant (beam) dynamics as well as performance of the feedback system. Beam dynamics can change significantly over the operating range of accelerator currents and energies . Here we present several methods for design of robust stabilizing feedback controllers. Experimental results from several accelerators are presented. A new baseband architecture for transverse feedback is described that compactly implements the digital processing functions using field-programmable gate array devices. The architecture is designed to be software configurable so that the same hardware can be used for instability control in different accelerators.

Architectures and Algorithms for Control and Diagnostics of Coupled-Bunch Instabilities in Circular Accelerators

International Nuclear Information System (INIS)

Teytelman, Dmitry

2003-01-01

Modern light sources and circular colliders employ large numbers of high-intensity particle bunches in order to achieve high luminosity. The electromagnetic coupling of bunches via resonant structures causes coherent instabilities at high beam currents. Achieving high luminosity requires the control of such unstable motion. Feedback control is challenging due to wideband nature of the problem with up to 250 MHz bandwidths required. This thesis presents digital signal processing architectures and diagnostic techniques for control of longitudinal and transverse coupled-bunch instabilities. Diagnostic capabilities integrated into the feedback system allow one to perform fast transient measurements of unstable dynamics by perturbing the beam from the controlled state via feedback and recording the time-domain response. Such measurements enable one to thoroughly characterize plant (beam) dynamics as well as performance of the feedback system. Beam dynamics can change significantly over the operating range of accelerator currents and energies . Here we present several methods for design of robust stabilizing feedback controllers. Experimental results from several accelerators are presented. A new baseband architecture for transverse feedback is described that compactly implements the digital processing functions using field-programmable gate array devices. The architecture is designed to be software configurable so that the same hardware can be used for instability control in different accelerators

Accelerated dissolution testing for controlled release microspheres using the flow-through dissolution apparatus.

Science.gov (United States)

Collier, Jarrod W; Thakare, Mohan; Garner, Solomon T; Israel, Bridg'ette; Ahmed, Hisham; Granade, Saundra; Strong, Deborah L; Price, James C; Capomacchia, A C

2009-01-01

Theophylline controlled release capsules (THEO-24 CR) were used as a model system to evaluate accelerated dissolution tests for process and quality control and formulation development of controlled release formulations. Dissolution test acceleration was provided by increasing temperature, pH, flow rate, or adding surfactant. Electron microscope studies on the theophylline microspheres subsequent to each experiment showed that at pH values of 6.6 and 7.6 the microspheres remained intact, but at pH 8.6 they showed deterioration. As temperature was increased from 37-57 degrees C, no change in microsphere integrity was noted. Increased flow rate also showed no detrimental effect on integrity. The effect of increased temperature was determined to be the statistically significant variable.

Strategies for Better Hypertension Control in India and Other Lower Middle Income Countries.

Science.gov (United States)

Gupta, Rajeev; Khedar, Raghuvir Singh; Panwar, Raja Babu

2016-09-01

Hypertension is the most important cause of global burden of disease. It is highly prevalent in India and other low and lower-middle income countries. Prevalence of uncontrolled hypertension varies from 70-90% and is significantly greater in rural vs urban locations. Guidelines based treatment strategy has improved blood pressure (BP) control in high income countries but no context-specific guidelines exist in low and lower-middle income countries such as India. There are numerous barriers to proper BP control in these countries and include political apathy, bureaucratic inertia, weak health systems, overburdened healthcare providers and unempowered patients. Hypertension control can be improved in these countries by better political focus on social determinants of health such as education, development of health systems, proper healthcare financing, free or low-cost BP medicines, healthcare provider education for hypertension management, free primary care, task sharing with trained community health workers, patient empowerment and use of technological innovations. © Journal of the Association of Physicians of India 2011.

Project and implementation of the control system for the microtron accelerator

International Nuclear Information System (INIS)

Malafronte, Alexandre Almeida

2008-01-01

The racetrack microtron under construction at the Instituto de Fisica da Universidade de Sao Paulo, is a recirculated electron accelerator that has a few hundred parameters to be monitored and controlled. These parameters belong to several subsystems like transport, vacuum, RF, and diagnostics. To decrease the cognitive burden of the operator and help him to control the machine a computerized control system was built, pervading all subsystems. This system allows the operator to measure and change the parameters of interest, or alerts him when some of these parameters exceed a pre-defined value. The system was built using the three-layer model methodology: input and output device layer; device server layer; and the user interface layer. In the input and output device layer, several instruments with different communication interfaces were used, either commercial or in-house built. In the device server layer industrial PCs were used. The user interface layer uses a conventional PC running a human-computer interface built with assistance of the Lab Windows/CVI software (National Instruments). The control system must satisfy requirements of flexibility, upgradability and cost, must stand during the accelerator lifetime and allow maintenance by the Lab's technical support. (author)

Customizable software architectures in the accelerator control system environment

CERN Document Server

Mejuev, I; Kadokura, E

2001-01-01

Tailoring is further evolution of an application after deployment in order to adapt it to requirements that were not accounted for in the original design. End-user customization has been extensively researched in applied computer science from HCI and software engineering perspectives. Customization allows coping with flexibility requirements, decreasing maintenance and development costs of software products. In general, dynamic or diverse software requirements constitute the need for implementing end-user customization in computer systems. In accelerator physics research the factor of dynamic requirements is especially important, due to frequent software and hardware modifications resulting in correspondingly high upgrade and maintenance costs. We introduce the results of feasibility study on implementing end-user tailorability in the software for accelerator control system, considering the design and implementation of a distributed monitoring application for the 12 GeV KEK Proton Synchrotron as an example. T...

Numerical investigation of closed-loop control for Hall accelerators

International Nuclear Information System (INIS)

Barral, S.; Miedzik, J.

2011-01-01

Low frequency discharge current oscillations in Hall accelerators are conventionally damped with external inductor-capacitor (LC) or resistor-inductor-capacitor (RLC) networks. The role of such network in the stabilization of the plasma discharge is investigated with a numerical model and the potential advantages of proportional-integral-derivative (PID) closed-loop control over RLC networks are subsequently assessed using either discharge voltage or magnetic field modulation. Simulations confirm the reduction of current oscillations in the presence of a RLC network, but suggest that PID control could ensure nearly oscillation-free operation with little sensitivity toward the PID settings.

Separating VNF and Network Control for Hardware‐Acceleration of SDN/NFV Architecture

Directory of Open Access Journals (Sweden)

Tong Duan

2017-08-01

Full Text Available A hardware‐acceleration architecture that separates virtual network functions (VNFs and network control (called HSN is proposed to solve the mismatch between the simple flow steering requirements and strong packet processing abilities of software‐defined networking (SDN forwarding elements (FEs in SDN/network function virtualization (NFV architecture, while improving the efficiency of NFV infrastructure and the performance of network‐intensive functions. HSN makes full use of FEs and accelerates VNFs through two mechanisms: (1 separation of traffic steering and packet processing in the FEs; (2 separation of SDN and NFV control in the FEs. Our HSN prototype, built on NetFPGA‐10G, demonstrates that the processing performance can be greatly improved with only a small modification of the traditional SDN/NFV architecture.

Accelerator diagnosis and control by Neural Nets

International Nuclear Information System (INIS)

Spencer, J.E.

1989-01-01

Neural Nets (NN) have been described as a solution looking for a problem. In the last conference, Artificial Intelligence (AI) was considered in the accelerator context. While good for local surveillance and control, its use for large complex systems (LCS) was much more restricted. By contrast, NN provide a good metaphor for LCS. It can be argued that they are logically equivalent to multi-loop feedback/forward control of faulty systems, and therefore provide an ideal adaptive control system. Thus, where AI may be good for maintaining a 'golden orbit,' NN should be good for obtaining it via a quantitative approach to 'look and adjust' methods like operator tweaking which use pattern recognition to deal with hardware and software limitations, inaccuracies or errors as well as imprecise knowledge or understanding of effects like annealing and hysteresis. Further, insights from NN allow one to define feasibility conditions for LCS in terms of design constraints and tolerances. Hardware and software implications are discussed and several LCS of current interest are compared and contrasted. 15 refs., 5 figs

Accelerator diagnosis and control by Neural Nets

International Nuclear Information System (INIS)

Spencer, J.E.

1989-01-01

Neural Nets (NN) have been described as a solution looking for a problem. In the last conference, Artificial Intelligence (AI) was considered in the accelerator context. While good for local surveillance and control, its use for large complex systems (LCS) was much more restricted. By contrast, NN provide a good metaphore for LCS. It can be argued that they are logically equivalent to multi-loop feedback/forward control of faulty systems and therefore provide an ideal adaptive control system. Thus, where A1 may be good for maintaining a golden orbit, NN should be good for obtaining it via a quantitative approach to look and adjust methods like operator tweaking which use pattern recognition to deal with hardware and software limitations, inaccuracies or errors as well as imprecise knowledge or understanding of effects like annealing and hysteresis. Further, insights from NN allow one to define feasibility conditions for LCS in terms of design constraints and tolerances. Hardware and software implications are discussed and several LCS of current interest are compared and contrasted. 15 refs., 5 figs

CVT control and vehicle acceleration; CVT hensoku ni yoru shasoku otosei

Energy Technology Data Exchange (ETDEWEB)

Takiyama, T; Morita, S [Osaka City University, Osaka (Japan)

1997-10-01

For the drivetrain control, it becomes important for fuel economy or AHS to control the throttle valve of the engine and the gear ratio of CVT simultaneously by DBW when CVT is equipped with the automobile. In this paper, LQI control theory was applied to control the drivetrain as 2-I/O system to satisfy the commanded speed and better fuel economy. And modification of the weight parameter of LQI was investigated to obtain the desired performance for fuel economy or vehicle acceleration. Relatively good expected results were obtained. 5 refs., 7 figs., 1 tab.

Simulation of speed control in acceleration mode of a heavy duty vehicle; Ogatasha no kasokuji ni okeru shasoku seigyo simulation

Energy Technology Data Exchange (ETDEWEB)

Endo, S; Ukawa, H [Isuzu Advanced Engineering Center, Ltd., Tokyo (Japan); Sanada, K; Kitagawa, A [Tokyo Institute of Technology, Tokyo (Japan)

1997-10-01

A control law of speed of a heavy duty vehicle in acceleration mode is presented, which is an extended version of a control law in deceleration mode proposed by the authors. The control law is based on constant acceleration strategy. Using the control law, target velocity and target distance can be performed. Both control laws for acceleration and deceleration mode can be represented by a unified mathematical formulae. Some simulation results are shown to demonstrate the control performance. 7 refs., 9 figs., 2 tabs.

Acceleration of 14C beams in electrostatic accelerators

International Nuclear Information System (INIS)

Rowton, L.J.; Tesmer, J.R.

1981-01-01

Operational problems in the production and acceleration of 14 C beams for nuclear structure research in Los Alamos National Laboratory's Van de Graaff accelerators are discussed. Methods for the control of contamination in ion sources, accelerators and personnel are described. Sputter source target fabrication techniques and the relative beam production efficiencies of various types of bound particulate carbon sputter source targets are presented

The upper level of control system of electron accelerators

International Nuclear Information System (INIS)

Gribov, I.V.; Nedeoglo, F.N.; Shvedunov, I.V.

2005-01-01

The upper level software of a three-level control system that supports several electron accelerators is described. This software operates in the Linux and RTLinux (Real Time Linux) environment. The object information model functions on the basis of a parametric description supported by the SQLite Data Base Management System. The Javascript sublanguage is used for script forming, and the Qt Designer application is used to construct the user interface [ru

Open Hardware for CERN's accelerator control systems

International Nuclear Information System (INIS)

Bij, E van der; Serrano, J; Wlostowski, T; Cattin, M; Gousiou, E; Sanchez, P Alvarez; Boccardi, A; Voumard, N; Penacoba, G

2012-01-01

The accelerator control systems at CERN will be upgraded and many electronics modules such as analog and digital I/O, level converters and repeaters, serial links and timing modules are being redesigned. The new developments are based on the FPGA Mezzanine Card, PCI Express and VME64x standards while the Wishbone specification is used as a system on a chip bus. To attract partners, the projects are developed in an 'Open' fashion. Within this Open Hardware project new ways of working with industry are being evaluated and it has been proven that industry can be involved at all stages, from design to production and support.

Distributed active traction control system applied to the RoboCup middle size league

OpenAIRE

Almeida, José; Dias, André; Sequeira, João; Martins, Alfredo; Silva, Eduardo

2013-01-01

This work addresses the problem of traction control in mobile wheeled robots in the particular case of the RoboCup Middle Size League (MSL). The slip control problem is formulated using simple friction models for ISePorto Team robots with a differential wheel configuration. Traction was also characterized experimentally in the MSL scenario for relevant game events. This work proposes a hierarchical traction control architecture which relies in local slip detection and con...

Do Children with Better Inhibitory Control Donate More? Differentiating between Early and Middle Childhood and Cool and Hot Inhibitory Control

Directory of Open Access Journals (Sweden)

Jian Hao

2017-12-01

Full Text Available Inhibitory control may play an important part in prosocial behavior, such as donating behavior. However, it is not clear at what developmental stage inhibitory control becomes associated with donating behavior and which aspects of inhibitory control are related to donating behavior during development in early to middle childhood. The present study aimed to clarify these issues with two experiments. In Experiment 1, 103 3- to 5-year-old preschoolers completed cool (Stroop-like and hot (delay of gratification inhibitory control tasks and a donating task. The results indicated that there were no relationships between cool or hot inhibitory control and donating behavior in the whole group and each age group of the preschoolers. In Experiment 2, 140 elementary school children in Grades 2, 4, and 6 completed cool (Stroop-like and hot (delay of gratification inhibitory control tasks and a donating task. The results showed that inhibitory control was positively associated with donating behavior in the whole group. Cool and hot inhibitory control respectively predicted donating behavior in the second and sixth graders. Therefore, the present study reveals that donating behavior increasingly relies on specific inhibitory control, i.e., hot inhibitory control as children grow in middle childhood.

Computer control of large accelerators design concepts and methods

International Nuclear Information System (INIS)

Beck, F.; Gormley, M.

1984-05-01

Unlike most of the specialities treated in this volume, control system design is still an art, not a science. These lectures are an attempt to produce a primer for prospective practitioners of this art. A large modern accelerator requires a comprehensive control system for commissioning, machine studies and day-to-day operation. Faced with the requirement to design a control system for such a machine, the control system architect has a bewildering array of technical devices and techniques at his disposal, and it is our aim in the following chapters to lead him through the characteristics of the problems he will have to face and the practical alternatives available for solving them. We emphasize good system architecture using commercially available hardware and software components, but in addition we discuss the actual control strategies which are to be implemented since it is at the point of deciding what facilities shall be available that the complexity of the control system and its cost are implicitly decided. 19 references

Computer control of large accelerators design concepts and methods

Energy Technology Data Exchange (ETDEWEB)

Beck, F.; Gormley, M.

1984-05-01

Unlike most of the specialities treated in this volume, control system design is still an art, not a science. These lectures are an attempt to produce a primer for prospective practitioners of this art. A large modern accelerator requires a comprehensive control system for commissioning, machine studies and day-to-day operation. Faced with the requirement to design a control system for such a machine, the control system architect has a bewildering array of technical devices and techniques at his disposal, and it is our aim in the following chapters to lead him through the characteristics of the problems he will have to face and the practical alternatives available for solving them. We emphasize good system architecture using commercially available hardware and software components, but in addition we discuss the actual control strategies which are to be implemented since it is at the point of deciding what facilities shall be available that the complexity of the control system and its cost are implicitly decided. 19 references.

Dual-harmonic auto voltage control for the rapid cycling synchrotron of the Japan Proton Accelerator Research Complex

Directory of Open Access Journals (Sweden)

Fumihiko Tamura

2008-07-01

Full Text Available The dual-harmonic operation, in which the accelerating cavities are driven by the superposition of the fundamental and the second harmonic rf voltage, is useful for acceleration of the ultrahigh intensity proton beam in the rapid cycling synchrotron (RCS of Japan Proton Accelerator Research Complex (J-PARC. However, the precise and fast voltage control of the harmonics is necessary to realize the dual-harmonic acceleration. We developed the dual-harmonic auto voltage control system for the J-PARC RCS. We describe details of the design and the implementation. Various tests of the system are performed with the RCS rf system. Also, a preliminary beam test has been done. We report the test results.

A novel beam focus control at the entrance to the ANU 14UD accelerator

International Nuclear Information System (INIS)

De Cesare, M.; Weisser, D. C.; Fifield, L. K.; Tunningley, T. B.; Lobanov, N. R.

2013-01-01

Tandem electrostatic accelerators often require the flexibility to operate at variety of terminal voltages to cater for various user needs. However beam transmission will only be optimal for a limited range of terminal voltages. This paper describes a focussing system that greatly expands the range of terminal voltages for optimal transmission. This is achieved by controlling the gradient of the entrance of the low-energy tube providing an additional controllable focusing element. Up to 150 kV is applied to the fifth electrode of the first unit of the accelerator tube giving control of the tube entrance lens strength. Beam tests to confirm the efficacy of the lens have been performed. These tests demonstrate that the entrance lens control eliminates the need to short out sections of the tube for low terminal voltage operation. (authors)

Accelerator facilities and development of physics in Kazakhstan (1992-2002)

International Nuclear Information System (INIS)

Shkol'nik, V.S.; Arzumanov, A.A.; Borisenko, A.N.; Gorlachev, I.D.; Kadyrzhanov, K.K.; Kuterbekov, K.A.; Lysukhin, S.N.; Tuleushev, A.Zh.

2003-01-01

The monograph is devoted to the use both the isochronous cyclotron U-150M and the accelerator of the heavy ions UKP-2-1, which are the base facilitates of the Institute of Nuclear Physics of the National Nuclear Center of the Republic of Kazakhstan (INP NNC RK) for scientific researches in the field of nuclear physics of low and middle energies, radiation solid state physics and applied nuclear physics. The history of creation of facilities, some archival documents are given The use of the accelerators of INP NNC RK for the last ten years (1992-2002) is described in detail. The parameters of facilities, photos of the main functional units of the accelerators as well as nuclear and physical methods realized on these basic facilities have been presented. The appendixes present copies of some important historical documents as well as the following materials: a list of on accelerator themes, a list of dissertation works, a list of publications of the Nuclear Physics Department within the period of 1972-2002 and the Solid State Department within the period of 1995-2002 carried out using the accelerators of INP NNC RK. The book is intended for scientists studying actual problems of nuclear physics of low and middle energies, radiation solid state physics as well as students specializing in this field (author)

Development of an Automatic Frequency Control (AFC) System for RF Electron Linear Accelerators

International Nuclear Information System (INIS)

Cha, Sungsu; Kim, Yujong; Lee, Byeong-No; Joo, Youngwoo; Lee, Soo Min; Lee, Byung Cheol; Cha, Hyungki; Park, Hyung Dal; Lee, Seung Hyun

2015-01-01

In this paper, the design, fabrication, and RF power test of the AFC system for the X-band linac are presented. The main function of the AFC system is automatically matching of the resonance frequency of the accelerating structure and the RF frequency of the magnetron. For the frequency tuning, a fine tuning of 10 kHz is possible by rotating the tuning shaft with a rotation of 0.72 degree per pulse. Therefore, the frequency deviation is about 0.01%, and almost full RF power (2.1 MW) transmission was obtained because the reflected power is minimized. The Radiation Equipment Research Division of the Korea Atomic Energy Research Institute has been developing and upgrading a medical/industrial X-band RF electron linear accelerators. The medical compact RF electron linear accelerator consists of an electron gun, an acceleration tube (accelerating structure), two solenoid magnets, two steering magnets, a magnetron, modulator, an automatic frequency control (AFC) system, and an X-ray generating target. The accelerating structure of the component is composed of oxygen-free high-conductivity copper (OFHC). Therefore, the volume of the structure, hence, its resonance frequency can easily be changeable if the ambient temperature and pressure are changed. If the RF frequency of the 9300 MHz magnetron and the resonance frequency of accelerating structure are not matched, performance of the structure can be degraded. An AFC system is automatically matched with the RF frequency of the magnetron and resonance frequency of the accelerating structure, which obtained a high output power and reliable accelerator operation

Development of an Automatic Frequency Control (AFC) System for RF Electron Linear Accelerators

Energy Technology Data Exchange (ETDEWEB)

Cha, Sungsu; Kim, Yujong; Lee, Byeong-No; Joo, Youngwoo; Lee, Soo Min; Lee, Byung Cheol; Cha, Hyungki [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, Hyung Dal [Radiation Technology eXcellence, Daejeon (Korea, Republic of); Lee, Seung Hyun [Sungkyunkwan University, Suwon (Korea, Republic of)

2015-10-15

In this paper, the design, fabrication, and RF power test of the AFC system for the X-band linac are presented. The main function of the AFC system is automatically matching of the resonance frequency of the accelerating structure and the RF frequency of the magnetron. For the frequency tuning, a fine tuning of 10 kHz is possible by rotating the tuning shaft with a rotation of 0.72 degree per pulse. Therefore, the frequency deviation is about 0.01%, and almost full RF power (2.1 MW) transmission was obtained because the reflected power is minimized. The Radiation Equipment Research Division of the Korea Atomic Energy Research Institute has been developing and upgrading a medical/industrial X-band RF electron linear accelerators. The medical compact RF electron linear accelerator consists of an electron gun, an acceleration tube (accelerating structure), two solenoid magnets, two steering magnets, a magnetron, modulator, an automatic frequency control (AFC) system, and an X-ray generating target. The accelerating structure of the component is composed of oxygen-free high-conductivity copper (OFHC). Therefore, the volume of the structure, hence, its resonance frequency can easily be changeable if the ambient temperature and pressure are changed. If the RF frequency of the 9300 MHz magnetron and the resonance frequency of accelerating structure are not matched, performance of the structure can be degraded. An AFC system is automatically matched with the RF frequency of the magnetron and resonance frequency of the accelerating structure, which obtained a high output power and reliable accelerator operation.

The new control system of the Saclay linear accelerator

International Nuclear Information System (INIS)

Gournay, J.F.; Gourcy, G.; Garreau, F.; Giraud, A.; Rouault, J.

1985-05-01

A new control system for the Safety Linear Accelerator is now being designed. The computer control architecture is based on 3 dedicated VME crates with MC68000 micro-processors: one crate with a disk-based operating system will run the high level application programs and the data base management facilities, another one will manage the man-machine communications and the third one will interface the system to the linac equipments. Communications between the VME microcomputers will be done through 16 bit parallel links. The software is modular and organized in specific layers, the data base is fully distributed. About 90% of the code is written in Fortran

Determination of acceleration for belt conveyor speed control in transient operation

NARCIS (Netherlands)

He, D.; Pang, Y.; Lodewijks, G.

2016-01-01

Speed control has been found a feasible mean to reduce the energy consumption of belt conveyors. However, the current research has not taken the determination of the acceleration in transient operation into account sufficiently. With respect to the belt tension rating, demanded safety factor and the

Open Hardware For CERN's Accelerator Control Systems

CERN Document Server

van der Bij, E; Ayass, M; Boccardi, A; Cattin, M; Gil Soriano, C; Gousiou, E; Iglesias Gonsálvez, S; Penacoba Fernandez, G; Serrano, J; Voumard, N; Wlostowski, T

2011-01-01

The accelerator control systems at CERN will be renovated and many electronics modules will be redesigned as the modules they will replace cannot be bought anymore or use obsolete components. The modules used in the control systems are diverse: analog and digital I/O, level converters and repeaters, serial links and timing modules. Overall around 120 modules are supported that are used in systems such as beam instrumentation, cryogenics and power converters. Only a small percentage of the currently used modules are commercially available, while most of them had been specifically designed at CERN. The new developments are based on VITA and PCI-SIG standards such as FMC (FPGA Mezzanine Card), PCI Express and VME64x using transition modules. As system-on-chip interconnect, the public domain Wishbone specification is used. For the renovation, it is considered imperative to have for each board access to the full hardware design and its firmware so that problems could quickly be resolved by CERN engineers or its ...

Exploring a new paradigm for accelerators and large experimental apparatus control systems

International Nuclear Information System (INIS)

Catani, L.; Ammendola, R.; Zani, F.; Bisegni, C.; Ciuffetti, P.; Di Pirro, G.; Mazzitelli, G.; Stecchi, A.; Calabro, S.; Foggetta, L.

2012-01-01

The integration of web technologies and web services has been, in the recent years, one of the major trends in upgrading and developing control systems for accelerators and large experimental apparatuses. Usually, web technologies have been introduced to complement the control systems with smart add-on and user friendly services or, for instance, to safely allow access to the control system to users from remote sites. Despite this still narrow spectrum of employment, some software technologies developed for high performance web services, although originally intended and optimized for these particular applications, deserve some features that would allow their deeper integration in a control system and, eventually, using them to develop some of the control system's core components. In this paper we present the conclusion of the preliminary investigations of a new design for an accelerator control system and associated machine data acquisition system (DAQ), based on a synergic combination of network distributed object caching (DOC) and a non-relational key/value database (KVDB). We investigated these technologies with particular interest on performances, namely speed of data storage and retrieve for the distributed caching, data throughput and queries execution time for the database and, especially, how much this performances can benefit from their inherent adaptability. (authors)

Research on heightening quality of free electron laser using superconducting linear accelerator

International Nuclear Information System (INIS)

Minehara, Eisuke

1996-01-01

In this paper, the superconducting high frequency linear accelerator technology using low temperature superconductor is introduced, and its application to the heightening of quality of free electron laser is discussed. The high frequency application of superconductivity is a relatively new technology, and the first superconducting high frequency linear accelerator was made at the middle of 1960s. The invention of free electron laser and the development so far are described. In free electron laser, the variation of wavelength, high efficiency and high power output are possible as compared with conventional type lasers. The price and the size are two demerits of free electron laser that remain to the last. In Japan Atomic Energy Research Institute, the adjustment experiment is carried out for the prototype free electron laser. About this prototype, injection system, superconducting accelerator, helium refrigerator, whole solid element high frequency power source, control system, electron beam transport system, undulator system and optical resonator are described. The application of high mean power output free electron laser and its future are discussed. (K.I.)

Modern operator's consoles for accelerator control at Fermilab

International Nuclear Information System (INIS)

Lucas, P.; Cahill, K.; Peters, R.; Smedinghoff, J.

1991-01-01

Since the construction of the Tevatron the Fermilab accelerator complex has been controlled from operator's consoles based on PDP-11 computers and interaction with display hardware via Camac. In addition the Linac has been controllable from microprocessor-based local consoles. The new generation of console devices is based on VAXstation computers, networked by Ethernet and Token Ring, and utilizing the X-windows protocol. Under X the physical display (server) can be driven by any network node, and need not be part of the console computer (client). This allows great flexibility in configuring display devices - with X-terminals, Unix workstations, and Macintoshes all having been utilized. Over half of the 800 application programs on the system have been demonstrated to work properly in the new environment. The modern version of a Linac local console runs in a Macintosh. These are networked via Token Ring to Linac local control stations. They provide color graphics and a hard copy capability which was previously lacking

The database for accelerator control in the CERN PS Complex

International Nuclear Information System (INIS)

Cuperus, J.H.

1987-01-01

The use of a database started 7 years ago and is an effort to separate logic from data so that programs and routines can do a larger number of operations on data structures without knowing a priori the contents of these structures. It is of great help in coping with the complexities of a system controlling many linked accelerators and storage rings

A Stable Formation Control Using Approximation of Translational and Angular Accelerations

Directory of Open Access Journals (Sweden)

Viet-Hong Tran

2011-03-01

Full Text Available In this paper, a stable leader-following formation control for multiple non-holonomic mobile robot systems using only limited on-board sensor information is proposed. The control can be used for the conventional single leader – single follower (SLSF or for novel two leaders – single follower (TLSF schemes. The control algorithm utilizes estimations of the leaders' translational and angular accelerations in a simple form to reduce the measurement of indirect information. Simulation results show that the TLSF scheme can suppress the oscillation and damping in formation of large robot teams.

Design and development of control instrumentation for the superconducting Linear Accelerator

International Nuclear Information System (INIS)

Joshi, Gopal; Kapatral, R.S.; Jha, K.; Rathod, N.C.; Sujo, C.I.; Ananthakrishnan, T.S.; Narsaiah, A.; Ghodgaonkar, M.D.; Kataria, S.K.; Singh, S.K.

2001-01-01

Electronics Division, BARC is developing the required control instrumentation for the Linear Accelerator (LINAC) coming up at TIFR. This consists of RF systems, CAMAC instruments and the Control and Information System. The control system consists of several identical Local Control Stations (LCS) connected over a LAN to a Main Control Station (MCS). Each LCS consists of a PC, CAMAC crates with functional Modules and RF systems. The MCS will contain two PCs running identical software. Each LCS will cater to two LINAC module each consisting of one cryostat and four resonators. This paper discusses different systems developed and under development in the Electronics Division which play an important role in the control of the LINAC. (author)

Optimization and test of a digital radio-frequency control system and developments for the EPICS-based accelerator control system at the S-DALINAC

International Nuclear Information System (INIS)

Burandt, Christoph Warwick

2017-01-01

The first part of this thesis covers multiple extensions of the digital low-level radio-frequency control system of the electron accelerator S-DALINAC. This comprises bringing into regular operation the piezoelectrically driven fine tuners of the superconducting cavities. For this a power supply series has been developed, which is compatible with the existing electronics and can power the piezo elements. Furthermore the flexibility of the radio-frequency control system has been demonstrated on superconducting quarter-wave-resonators of the ion accelerator ALPI. These 160 MHz cavities are quite different to the S-DALINAC's acceleration structures but could be operated successfully with low residual errors in phase and amplitude nevertheless. The second part describes the migration of the accelerator control system to an EPICS-based system. A multitude of devices with a diversity of interfaces and protocols have been integrated and higher-level functionality has been unified. Within the framework of the construction of the third recirculation beam-line, the beam-path-length adjustment mechanism was motorized.

Robust flight control using incremental nonlinear dynamic inversion and angular acceleration prediction

NARCIS (Netherlands)

Sieberling, S.; Chu, Q.P.; Mulder, J.A.

2010-01-01

This paper presents a flight control strategy based on nonlinear dynamic inversion. The approach presented, called incremental nonlinear dynamic inversion, uses properties of general mechanical systems and nonlinear dynamic inversion by feeding back angular accelerations. Theoretically, feedback of

Comparing joint kinematics and center of mass acceleration as feedback for control of standing balance by functional neuromuscular stimulation.

Science.gov (United States)

Nataraj, Raviraj; Audu, Musa L; Triolo, Ronald J

2012-05-06

The purpose of this study was to determine the comparative effectiveness of feedback control systems for maintaining standing balance based on joint kinematics or total body center of mass (COM) acceleration, and assess their clinical practicality for standing neuroprostheses after spinal cord injury (SCI). In simulation, controller performance was measured according to the upper extremity effort required to stabilize a three-dimensional model of bipedal standing against a variety of postural disturbances. Three cases were investigated: proportional-derivative control based on joint kinematics alone, COM acceleration feedback alone, and combined joint kinematics and COM acceleration feedback. Additionally, pilot data was collected during external perturbations of an individual with SCI standing with functional neuromuscular stimulation (FNS), and the resulting joint kinematics and COM acceleration data was analyzed. Compared to the baseline case of maximal constant muscle excitations, the three control systems reduced the mean upper extremity loading by 51%, 43% and 56%, respectively against external force-pulse perturbations. Controller robustness was defined as the degradation in performance with increasing levels of input errors expected with clinical deployment of sensor-based feedback. At error levels typical for body-mounted inertial sensors, performance degradation due to sensor noise and placement were negligible. However, at typical tracking error levels, performance could degrade as much as 86% for joint kinematics feedback and 35% for COM acceleration feedback. Pilot data indicated that COM acceleration could be estimated with a few well-placed sensors and efficiently captures information related to movement synergies observed during perturbed bipedal standing following SCI. Overall, COM acceleration feedback may be a more feasible solution for control of standing with FNS given its superior robustness and small number of inputs required.

Mind Your Step : Exploring aspects in the application of long accelerating moving walkways

NARCIS (Netherlands)

Kusumaningtyas, I.

2009-01-01

Accelerating Moving Walkways (AMWs) are conveyor systems that accelerate pedestrians from a low speed at the entrance to a higher speed at the middle section, and then decelerate them to a low speed again at the exit. It is envisaged they can be a potential transport mode to fill the gap between

Implementation of a quality control program for a 6 MeV linear photon accelerator

International Nuclear Information System (INIS)

Berdaky, Mafalda F.; Caldas, Linda V.E.

2001-01-01

This paper describes the operational characteristics of the final process of implementation of a quality control program using routine mechanical and radiation tests. The quality control program was performed during 35 months and demonstrated the excellent stability of this accelerator. (author)

A shot parameter specification subsystem for automated control of PBFA II accelerator shots

International Nuclear Information System (INIS)

Spiller, J.L.

1987-01-01

The author reports on the shot parameter specification subsystem (SPSS), an integral part of the automatic control system developed for the Particle Beam Fusion Accelerator II (PBFA II). This system has been designed to fully utilize the accelerator by tailoring shot parameters to the needs of the experimenters. The SPSS is the key to this flexibility. Automatic systems will be required on many pulsed power machines for the fastest turnaround, the highest reliability, and most cost effective operation. These systems will require the flexibility and the ease of use that is part of the SPSS. The author discusses how the PBFA II control system has proved to be an effective modular system, flexible enough to meet the demands of both the fast track construction of PBFA II and the control needs of Hermes III. This system is expected to meet the demands of most future machine changes

Implementation to spanish protocol of quality control of accelerators to daily control of electron beams

International Nuclear Information System (INIS)

Adaimi Hernandez, P.; Ramirez Ros, J. C.; Casa de Julian, M. A. de la; Clemente Gutierrez, F.; Cabello Murillo, E.; Diaz Fuente, R.; Ferrando Sanchez, A.

2011-01-01

A revised procedure for daily control of the electron beams to make measurements more meaningful physically, having a better reproducibility and more in line with the recommendations of the Spanish Protocol for Quality Control in Electron Linear Accelerators Clinical Use. The daily quality control beams of high energy electrons that had been done so far was the finding that the record of a series of measures (symmetry, uniformity, stability, energy, beam central dose) were within tolerance values established. The amendment is to check the beam quality by directly measuring changes in absorption depth at which the dose is reduced to half its maximum value, R50.

The distributed control system of Shanghai mini-cyclotron accelerator mass spectrometer (SMCAMS)

International Nuclear Information System (INIS)

Shao Yuhe

2001-01-01

It is mainly introduced the composition, structure, hardware and software designing, function, and the method of communication between the host computer and the ADAM modules of the distributed control system on Shanghai Mini-cyclotron Accelerator Mass Spectrometer (SMCAMS). Some detail problems such as controlling the devices staying on high voltage by ADAM-4541 (RS-485 to Fiber Optic Convertor) and optical fiber are also introduced

Center of Mass Acceleration Feedback Control of Standing Balance by Functional Neuromuscular Stimulation against External Postural Perturbations

Science.gov (United States)

Nataraj, Raviraj; Audu, Musa L.; Triolo, Ronald J.

2013-01-01

This study investigated the use of center of mass (COM) acceleration feedback for improving performance of a functional neuromuscular stimulation (FNS) control system to restore standing function to a subject with complete, thoracic-level spinal cord injury (SCI). The approach for linearly relating changes in muscle stimulation to changes in COM acceleration was verified experimentally and subsequently produced data to create an input-output map driven by sensor feedback. The feedback gains were systematically tuned to reduce upper extremity (UE) loads applied to an instrumented support device while resisting external postural disturbances. Total body COM acceleration was accurately estimated (> 89% variance explained) using three-dimensional (3-D) outputs of two accelerometers mounted on the pelvis and torso. Compared to constant muscle stimulation employed clinically, feedback control of stimulation reduced UE loading by 33%. COM acceleration feedback is advantageous in constructing a standing neuroprosthesis since it provides the basis for a comprehensive control synergy about a global, dynamic variable and requires minimal instrumentation. Future work should include tuning and testing the feedback control system during functional reaching activity that is more indicative of activities of daily living. PMID:22987499

POPS: the 60MW power converter for the PS accelerator: Control strategy and performances

CERN Document Server

Boattini, Fulvio; Skawinski, Gregory

2015-01-01

The main power supply of Proton-Synchrotron (PS) accelerator is one of the biggest at CERN. The old rotating machine system has been replaced with a new NPC based DC/DC power supply named POPS (Power system for PS main magnets) with capacitor banks as energy storage mean. POPS is in operation since February 2011. The operation of the PS accelerator requires a specific design of the control system with very high performance requirements in term of accuracy and precision. This paper describes the main lines of the control strategies analyzing the problems encountered and the solutions adopted. The performances of the converter are presented throughout the paper.

Cherenkov Radiation Control via Self-accelerating Wave-packets.

Science.gov (United States)

Hu, Yi; Li, Zhili; Wetzel, Benjamin; Morandotti, Roberto; Chen, Zhigang; Xu, Jingjun

2017-08-18

Cherenkov radiation is a ubiquitous phenomenon in nature. It describes electromagnetic radiation from a charged particle moving in a medium with a uniform velocity larger than the phase velocity of light in the same medium. Such a picture is typically adopted in the investigation of traditional Cherenkov radiation as well as its counterparts in different branches of physics, including nonlinear optics, spintronics and plasmonics. In these cases, the radiation emitted spreads along a "cone", making it impractical for most applications. Here, we employ a self-accelerating optical pump wave-packet to demonstrate controlled shaping of one type of generalized Cherenkov radiation - dispersive waves in optical fibers. We show that, by tuning the parameters of the wave-packet, the emitted waves can be judiciously compressed and focused at desired locations, paving the way to such control in any physical system.

Multichannel computerized control system of current pulses in LIU-30 electron accelerator

CERN Document Server

Gerasimov, A I; Kulgavchuk, V V; Pluzhnikov, A V

2002-01-01

In LIU-30 power linear pulsed induction electron accelerator (40 MeV, 10 kA, 25 ns) 288 radial lines with water insulation serve as energy accumulators and shapers of accelerating voltage pulses. The lines are charged simultaneously up to 500 kV using a system comprising 72 Arkadiev-Marx screened generators. To control parameter of synchronous pulses of charging current with up to 60 kA amplitude and 0.85 mu s duration in every of 72 charging circuits one applies a computer-aided system. Current pulse is recorded at output of every generator using the Rogowski coil signal from which via a cable line is transmitted to an analog-digital converter, is processed with 50 ns sampling and is recorded to a memory unit. Upon actuation of accelerator the signals are sequentially or selectively displayed and are compared with pulse typical shape

Comparing joint kinematics and center of mass acceleration as feedback for control of standing balance by functional neuromuscular stimulation

Directory of Open Access Journals (Sweden)

Nataraj Raviraj

2012-05-01

Full Text Available Abstract Background The purpose of this study was to determine the comparative effectiveness of feedback control systems for maintaining standing balance based on joint kinematics or total body center of mass (COM acceleration, and assess their clinical practicality for standing neuroprostheses after spinal cord injury (SCI. Methods In simulation, controller performance was measured according to the upper extremity effort required to stabilize a three-dimensional model of bipedal standing against a variety of postural disturbances. Three cases were investigated: proportional-derivative control based on joint kinematics alone, COM acceleration feedback alone, and combined joint kinematics and COM acceleration feedback. Additionally, pilot data was collected during external perturbations of an individual with SCI standing with functional neuromuscular stimulation (FNS, and the resulting joint kinematics and COM acceleration data was analyzed. Results Compared to the baseline case of maximal constant muscle excitations, the three control systems reduced the mean upper extremity loading by 51%, 43% and 56%, respectively against external force-pulse perturbations. Controller robustness was defined as the degradation in performance with increasing levels of input errors expected with clinical deployment of sensor-based feedback. At error levels typical for body-mounted inertial sensors, performance degradation due to sensor noise and placement were negligible. However, at typical tracking error levels, performance could degrade as much as 86% for joint kinematics feedback and 35% for COM acceleration feedback. Pilot data indicated that COM acceleration could be estimated with a few well-placed sensors and efficiently captures information related to movement synergies observed during perturbed bipedal standing following SCI. Conclusions Overall, COM acceleration feedback may be a more feasible solution for control of standing with FNS given its

Centrifuge Study of Pilot Tolerance to Acceleration and the Effects of Acceleration on Pilot Performance

Science.gov (United States)

Creer, Brent Y.; Smedal, Harald A.; Wingrove, Rodney C.

1960-01-01

A research program the general objective of which was to measure the effects of various sustained accelerations on the control performance of pilots, was carried out on the Aviation Medical Acceleration Laboratory centrifuge, U.S. Naval Air Development Center, Johnsville, PA. The experimental setup consisted of a flight simulator with the centrifuge in the control loop. The pilot performed his control tasks while being subjected to acceleration fields such as might be encountered by a forward-facing pilot flying an atmosphere entry vehicle. The study was divided into three phases. In one phase of the program, the pilots were subjected to a variety of sustained linear acceleration forces while controlling vehicles with several different sets of longitudinal dynamics. Here, a randomly moving target was displayed to the pilot on a cathode-ray tube. For each combination of acceleration field and vehicle dynamics, pilot tracking accuracy was measured and pilot opinion of the stability and control characteristics was recorded. Thus, information was obtained on the combined effects of complexity of control task and magnitude and direction of acceleration forces on pilot performance. These tests showed that the pilot's tracking performance deteriorated markedly at accelerations greater than about 4g when controlling a lightly damped vehicle. The tentative conclusion was also reached that regardless of the airframe dynamics involved, the pilot feels that in order to have the same level of control over the vehicle, an increase in the vehicle dynamic stability was required with increases in the magnitudes of the acceleration impressed upon the pilot. In another phase, boundaries of human tolerance of acceleration were established for acceleration fields such as might be encountered by a pilot flying an orbital vehicle. A special pilot restraint system was developed to increase human tolerance to longitudinal decelerations. The results of the tests showed that human tolerance

America's Call to Islam in the Middle East: The Information War

National Research Council Canada - National Science Library

Leach, Walter H

2005-01-01

While the United States armed forces are working hard to defeat terrorists wherever they can be found the country is also engaged on the information front to accelerate the introduction of democracy into the Middle East...

The graphics software of the Saclay linear accelerator control system

International Nuclear Information System (INIS)

Gournay, J.F.

1987-06-01

The Control system of the Saclay Linear Accelerator is based upon modern technology hardware. In the graphic software, pictures are created in exactly the same manner for all the graphic devices supported by the system. The informations used to draw a picture are stored in an array called a graphic segment. Three output primitives are used to add graphic material in a segment. Three coordinate systems are defined

Monitoring and control system of the Saclay electron linear accelerator

International Nuclear Information System (INIS)

Lafontaine, Antoine

1974-01-01

A description is given of the automatic monitoring and control system of the 60MeV electron linear accelerator of the Centre d'Etudes Nucleaires de Saclay. The paper is mostly concerned with the programmation of the system. However, in a real time device, there is a very close association between computer and electronics, the latter are therefore described in details and make up most of the paper. [fr

Tools for remote computing in accelerator control

International Nuclear Information System (INIS)

Anderssen, P.S.; Frammery, V.; Wilcke, R.

1990-01-01

In modern accelerator control systems, the intelligence of the equipment is distributed in the geographical and the logical sense. Control processes for a large variety of tasks reside in both the equipment and the control computers. Hence successful operation hinges on the availability and reliability of the communication infrastructure. The computers are interconnected by a communication system and use remote procedure calls and message passing for information exchange. These communication mechanisms need a well-defined convention, i.e. a protocol. They also require flexibility in both the setup and changes to the protocol specification. The network compiler is a tool which provides the programmer with a means of establishing such a protocol for his application. Input to the network compiler is a single interface description file provided by the programmer. This file is written according to a grammar, and completely specifies the interprocess communication interfaces. Passed through the network compiler, the interface description file automatically produces the additional source code needed for the protocol. Hence the programmer does not have to be concerned about the details of the communication calls. Any further additions and modifications are made easy, because all the information about the interface is kept in a single file. (orig.)

Error analysis of acceleration control loops of a synchrotron

International Nuclear Information System (INIS)

Zhang, S.Y.; Weng, W.T.

1991-01-01

For beam control during acceleration, it is conventional to derive the frequency from an external reference, be it a field marker or an external oscillator, to provide phase and radius feedback loops to ensure the phase stability, radial position and emittance integrity of the beam. The open and closed loop behaviors of both feedback control and their response under the possible frequency, phase and radius errors are derived from fundamental principles and equations. The stability of the loops is investigated under a wide range of variations of the gain and time delays. Actual system performance of the AGS Booster is analyzed and compared to commissioning experiences. Such analysis is useful for setting design criteria and tolerances for new proton synchrotrons. 4 refs., 13 figs

The new control system of the Saclay linear accelerator

International Nuclear Information System (INIS)

Gournay, J.F.

1985-10-01

A new control system for the Saclay Linear Accelerator designed during the two past years is now in operation. The computer control architecture is based on 3 dedicated VME crates: one crate with a disk-based operating system runs the high level application programs and the database management facilities, another one manages the man-machine communications and the third one interfaces the system to the linac equipments. At the present time, communications between the VME micro-computers are done through 16 bit parallel links. The software is modular and organized in specific layers, the database is fully distributed. About 90% of the code is written in Fortran. The present status of the system is discussed and the hardware and software developments are described

Instrumentation and control system for the AT-2 accelerator test stand

International Nuclear Information System (INIS)

Wadlinger, E.A.; Holtkamp, D.B.; Holt, H.D.

1984-01-01

A data-driven subroutine package, written for our accelerator test stand (ATS), is described. This flexible package permits the rapid writing and modifying of data acquisition, control, and analysis programs for the many diverse experiments performed on the ATS. These structurally simple and easy to maintain routines help to control administratively the integrity of the ATS through the use of the database. Our operating experience indicates that the original design goals have been met. We describe the subroutines, database, and our experiences with this system

Development of a remote control console for the HHIRF 25-MV tandem accelerator

International Nuclear Information System (INIS)

Hasanul Basher, A.M.

1991-09-01

The CAMAC-based control system for the 25-MV Tandem Accelerator at HHIRF uses two Perkin-Elmer, 32-bit minicomputers: a message-switching computer and a supervisory computer. Two operator consoles are located on one of the six serial highways. Operator control is provided by means of a console CRT, trackball, assignable shaft encoders and meters. The message-switching computer transmits and receives control information on the serial highways. At present, the CRT pages with updated parameters can be displayed and parameters can be controlled only from the two existing consoles, one in the Tandem control room and the other in the ORIC control room. It has become necessary to expand the control capability to several other locations in the building. With the expansion of control and monitoring capability of accelerator parameters to other locations, the operators will be able to control and observe the result of the control action at the same time. Since the new control console will be PC-based, the existing page format will be changed. The PC will be communicating with the Perkin-Elmer through RS-232 and a communication software package. Hardware configuration has been established, a communication software program that reads the pages from the shared memory has been developed. In this paper, we present the implementation strategy, works completed, existing and new page format, future action plans, explanation of pages and use of related global variables, a sample session, and flowcharts

Radiation protection of the operation of accelerator facilities. On high energy proton and electron accelerators

International Nuclear Information System (INIS)

Kondo, Kenjiro

1997-01-01

Problems in the radiation protection raised by accelerated particles with energy higher than several hundreds MeV in strong accelerator facilities were discussed in comparison with those with lower energy in middle- and small-scale facilities. The characteristics in the protection in such strong accelerator facilities are derived from the qualitative changes in the interaction between the high energy particles and materials and from quantitative one due to the beam strength. In the former which is dependent on the emitting mechanism of the radiation, neutron with broad energy spectrum and muon are important in the protection, and in the latter, levels of radiation and radioactivity which are proportional to the beam strength are important. The author described details of the interaction between high energy particles and materials: leading to the conclusion that in the electron accelerator facilities, shielding against high energy-blemsstrahlung radiation and -neutron is important and in the proton acceleration, shielding against neutron is important. The characteristics of the radiation field in the strong accelerator facilities: among neutron, ionized particles and electromagnetic wave, neutron is most important in shielding since it has small cross sections relative to other two. Considerations for neutron are necessary in the management of exposure. Multiplicity of radionuclides produced: which is a result of nuclear spallation reaction due to high energy particles, especially to proton. Radioactivation of the accelerator equipment is a serious problem. Other problems: the interlock systems, radiation protection for experimenters and maintenance of the equipment by remote systems. (K.H.). 11 refs

Digital base-band rf control system for the superconducting Darmstadt electron linear accelerator

Directory of Open Access Journals (Sweden)

M. Konrad

2012-05-01

Full Text Available The accelerating field in superconducting cavities has to be stabilized in amplitude and phase by a radio-frequency (rf control system. Because of their high loaded quality factor superconducting cavities are very susceptible for microphonics. To meet the increased requirements with respect to accuracy, availability, and diagnostics, the previous analog rf control system of the superconducting Darmstadt electron linear accelerator S-DALINAC has been replaced by a digital rf control system. The new hardware consists of two components: An rf module that converts the signal from the cavity down to the base-band and a field-programmable gate array board including a soft CPU that carries out the signal processing steps of the control algorithm. Different algorithms are used for normal-conducting and superconducting cavities. To improve the availability of the control system, techniques for automatic firmware and software deployment have been implemented. Extensive diagnostic features provide the operator with additional information. The architecture of the rf control system as well as the functionality of its components will be presented along with measurements that characterize the performance of the system, yielding, e.g., an amplitude stabilization down to (ΔA/A_{rms}=7×10^{-5} and a phase stabilization of (Δϕ_{rms}=0.8° for superconducting cavities.

Design, construction and installation of the electromechanical components of the current control of filament of the Pelletron Electron Accelerator

International Nuclear Information System (INIS)

Aguilar J, R.A.; Valdovinos A, M.; Lopez V, H.

1985-01-01

For the operation of the Pelletron electron accelerator is required to have control of the filament current. For it was designed, built and installed an electromechanical system located in the Acceleration Unit inside the Accelerator tank and operated from the Control console. All the components located inside the tank operated under the following conditions: Pressure: until 7.03 Kg/cm 2 ; High voltage: 10 6 V (only the insulating arrow); Atmosphere: mixture of N 2 and CO 2 or SF 6 . (Author)

Fibre optic control for electron gun power supplies and data acquisition of 3 MeV DC accelerator

International Nuclear Information System (INIS)

Chavan, R.B.; Yadav, Vivek; Dixit, K.P.; Bakhtsingh, R.I.; Rajan, Rehim; Nanu, K.; Mittal, K.C.; Chakravarthy, D.P.; Gantayet, L.M.

2011-01-01

A 3 MeV, 10 mA DC Industrial Electron Beam Accelerator is being commissioned at Electron Beam Centre, Navi Mumbai. The electron beam is generated by a triode electron gun and injected into the accelerating column at 5 keV. The gun and its power supplies, (5 kV anode, 3 kV grid and 15V/20A filament), are floating at 3 Million volts, and are situated in a tank which is pressurized with SF6 at 6 kg/cm 2 . These power supplies are required to be controlled remotely. The various accelerator parameters like Beam Energy, Beam Current, RF Electrode Voltage, Power Oscillator Plate Voltage / Current and Vacuum are required to be monitored during beam operation. The software was developed in VB.Net for control and data acquisition. The database is provided in SQL 2005 for storing the data. For this purpose, control system using ADAM modules and Optical fibre has been designed and developed. This paper describes the design features of the control system and experience of use of control software during initial beam trials. (author)

Improved transmission of electrostatic accelerator in a wide range of terminal voltages by controlling the focal strength of entrance acceleration tube

Science.gov (United States)

Lobanov, Nikolai R.; Tunningley, Thomas; Linardakis, Peter

2018-04-01

Tandem electrostatic accelerators often require the flexibility to operate at a variety of terminal voltages to accommodate various user requirements. However, the ion beam transmission will only be optimal for a limited range of terminal voltages. This paper describes the operational performance of a novel focusing system that expands the range of terminal voltages for optimal transmission. This is accomplished by controlling the gradient of the entrance of the low-energy tube, providing an additional focusing element. In this specific case it is achieved by applying up to 150 kV to the fifth electrode of the first unit of the accelerator tube. Numerical simulations and beam transmission tests have been performed to confirm the effectiveness of the lens. An analytical expression has been derived describing its focal properties. These tests demonstrate that the entrance lens control eliminates the need to short out sections of the tube for operation at low terminal voltage.

Middle East Respiratory Syndrome (MERS)

Science.gov (United States)

Middle East Respiratory Syndrome Coronavirus; MERS-CoV; Novel coronavirus; nCoV ... for Disease Control and Prevention website. Middle East Respiratory Syndrome (MERS): Frequently asked questions and answers. www. ...

Microprocessor control and data acquisition at the LLNL 100-MeV accelerator

International Nuclear Information System (INIS)

Mendonca, M.L.

1981-01-01

A distributed microprocessor control and data acquisition network has been designed for implementation on the Lawrence Livermore National Laboratory 100 MeV electron/positron accelerator (LINAC). The system has been designed to be as transparent to the user as possible by stressing responsiveness, reliability, and relevance of data presented to the user. Implementation of the network will take place in modular fashion in three stages, so as to minimize disruption of normal operations. The first elements to be installed will be the beam transport system controls, beam set-up time. Beam diagnostic equipment is now being position monitors, and accelerator operating status monitors. These units will reduce beam set-up time. Beam diagnostic equipment is now being designed that will be used in a second stage implementation. This stage will concentrate on determining beam parameters and allowing the user to optimize the beam for a given parameter. The final stage will be to install experimenter data acquisition equipment. The equipment will augment the presently existing data acquisition system. The completed network will allow a more efficient operation of the LINAC, resulting in reduced experiment costs, and more controllable beam parameters, both of which are major concerns of experimenters

A quality control method for detecting energy changes of medical accelerators

International Nuclear Information System (INIS)

McGinley, P.H.

2000-01-01

A description is presented of a simple and sensitive method for detecting a change in the energy of the electrons bombarding the target of medical accelerators. This technique is useful for x-ray beams with end point energy in the range of 15.7 to 25 MeV. The method is based on the photoactivation of 16 O and 14 N in a small sample of ammonium nitrate. It was found that the ratio of the activity induced in the oxygen divided by that produced in the nitrogen can be used as a quality control technique to detect a change in the energy of the electrons that bombard the target of the accelerator. An electron energy change of the order of 0.2 MeV can be determined using this method. (author)

Ultrasound Instrumentation for Beam Diagnostics and Accelerating Structures Control

CERN Document Server

Moiseev, V I

2005-01-01

Sensitive elements and electronics for ultrasound measurements at conducting walls of beam pipes and accelerating structures are described. Noise protected instrumentation provides ultrasound spectra analysis in a wide frequency range up to 5 MHz.In circular accelerators, ultrasound fields in conducting walls of beam pipe represent the space-time characteristics of circulating beams. In accelerating structures, real high power operation modes of structure can be studied by outer ultrasound monitors. The experimental results at KSRS accelerators are discussed.

Spallation Neutron Source Accelerator Facility Target Safety and Non-safety Control Systems

International Nuclear Information System (INIS)

Battle, Ronald E.; DeVan, B.; Munro, John K. Jr.

2006-01-01

The Spallation Neutron Source (SNS) is a proton accelerator facility that generates neutrons for scientific researchers by spallation of neutrons from a mercury target. The SNS became operational on April 28, 2006, with first beam on target at approximately 200 W. The SNS accelerator, target, and conventional facilities controls are integrated by standardized hardware and software throughout the facility and were designed and fabricated to SNS conventions to ensure compatibility of systems with Experimental Physics Integrated Control System (EPICS). ControlLogix Programmable Logic Controllers (PLCs) interface to instruments and actuators, and EPICS performs the high-level integration of the PLCs such that all operator control can be accomplished from the Central Control room using EPICS graphical screens that pass process variables to and from the PLCs. Three active safety systems were designed to industry standards ISA S84.01 and IEEE 603 to meet the desired reliability for these safety systems. The safety systems protect facility workers and the environment from mercury vapor, mercury radiation, and proton beam radiation. The facility operators operated many of the systems prior to beam on target and developed the operating procedures. The safety and non-safety control systems were tested extensively prior to beam on target. This testing was crucial to identify wiring and software errors and failed components, the result of which was few problems during operation with beam on target. The SNS has continued beam on target since April to increase beam power, check out the scientific instruments, and continue testing the operation of facility subsystems

Establishment of a radiotherapy service with a linear accelerator (photons): acceptance tests, dosimetry and quality control

International Nuclear Information System (INIS)

Berdaky, Mafalda Feliciano

2000-01-01

This work presents the operational part of the final process of the establishment of a radiotherapy service with a linear accelerator (6 MeV photon beams), including the acceptance tests, commissioning tests and the implementation of a quality control program through routine mechanical and radiation tests. All acceptance tests were satisfactory, showing results below the allowed limits of the manufacturer, the commissioning tests presented results within those of the international recommendations. The quality control program was performed during 34 months and showed an excellent stability of this accelerator. (author)

Device Configuration Handler for Accelerator Control Applications at Jefferson Lab

International Nuclear Information System (INIS)

Bickley, Matt; Chevtsov, P.; Larrieu, T.

2003-01-01

The accelerator control system at Jefferson Lab uses hundreds of physical devices with such popular instrument bus interfaces as Industry Pack (IPAC), GPIB, RS-232, etc. To properly handle all these components, control computers (IOCs) must be provided with the correct information about the unique memory addresses of the used interface cards, interrupt numbers (if any), data communication channels and protocols. In these conditions, the registration of a new control device in the control system is not an easy task for software developers. Because the device configuration is distributed, it requires the detailed knowledge about not only the new device but also the configuration of all other devices on the existing system. A configuration handler implemented at Jefferson Lab centralizes the information about all control devices making their registration user-friendly and very easy to use. It consists of a device driver framework and the device registration software developed on the basis of ORACLE database and freely available scripting tools (perl, php)

Unified accelerator libraries

International Nuclear Information System (INIS)

Malitsky, Nikolay; Talman, Richard

1997-01-01

A 'Universal Accelerator Libraries' (UAL) environment is described. Its purpose is to facilitate program modularity and inter-program and inter-process communication among heterogeneous programs. The goal ultimately is to facilitate model-based control of accelerators

Engineering a large application software project: the controls of the CERN PS accelerator complex

International Nuclear Information System (INIS)

Benincasa, G.P.; Daneels, A.; Heymans, P.; Serre, Ch.

1985-01-01

The CERN PS accelerator complex has been progressively converted to full computer controls without interrupting its full-time operation (more than 6000 hours per year with on average not more than 1% of the total down-time due to controls). The application software amounts to 120 man-years and 450'000 instructions: it compares with other large software projects, also outside the accelerator world: e.g. Skylab's ground support software. This paper outlines the application software structure which takes into account technical requirements and constraints (resulting from the complexity of the process and its operation) and economical and managerial ones. It presents the engineering and management techniques used to promote implementation, testing and commissioning within budget, manpower and time constraints and concludes with experience gained

Automation tools for accelerator control a network based sequencer

International Nuclear Information System (INIS)

Clout, P.; Geib, M.; Westervelt, R.

1991-01-01

In conjunction with a major client, Vista Control Systems has developed a sequencer for control systems which works in conjunction with its realtime, distributed Vsystem database. Vsystem is a network-based data acquisition, monitoring and control system which has been applied successfully to both accelerator projects and projects outside this realm of research. The network-based sequencer allows a user to simply define a thread of execution in any supported computer on the network. The script defining a sequence has a simple syntax designed for non-programmers, with facilities for selectively abbreviating the channel names for easy reference. The semantics of the script contains most of the familiar capabilities of conventional programming languages, including standard stream I/O and the ability to start other processes with parameters passed. The script is compiled to threaded code for execution efficiency. The implementation is described in some detail and examples are given of applications for which the sequencer has been used

Microprocessor supervised stability control system for the united power system of Middle Volga in fault conditions

Energy Technology Data Exchange (ETDEWEB)

Berdnikov, V I; Birgel, E R; Kovalev, V D; Kuznestov, A N

1994-12-31

The development of the 500 kV UPS of Middle Volga, the complication of its configuration and operating conditions particularly in connection with concentration of the generating power at Balakovo NPS have aggravated the problem of stability of the Middle Volga UPS when high power is transmitted along the 500 kV transient system. In this case the necessity for improving control actions` dosage accuracy has also appeared. This work discusses solution to the above mentioned issue. (author) 3 figs.

Applications toolkit for accelerator control and analysis

International Nuclear Information System (INIS)

Borland, M.

1997-01-01

The Advanced Photon Source (APS) has taken a unique approach to creating high-level software applications for accelerator operation and analysis. The approach is based on self-describing data, modular program toolkits, and scripts. Self-describing data provide a communication standard that aids the creation of modular program toolkits by allowing compliant programs to be used in essentially arbitrary combinations. These modular programs can be used as part of an arbitrary number of high-level applications. At APS, a group of about 70 data analysis, manipulation, and display tools is used in concert with about 20 control-system-specific tools to implement applications for commissioning and operations. High-level applications are created using scripts, which are relatively simple interpreted programs. The Tcl/Tk script language is used, allowing creating of graphical user interfaces (GUIs) and a library of algorithms that are separate from the interface. This last factor allows greater automation of control by making it easy to take the human out of the loop. Applications of this methodology to operational tasks such as orbit correction, configuration management, and data review will be discussed

Recirculator "SALO" - A basis for creation of a model of sub-critical reactor controlled by the accelerator

NARCIS (Netherlands)

Gann, V.V.; Guk, I.S.; Dovbnya, A.N.; Kononenko, S.G.; Kostromin, A.S.; Peev, F.A.; Prochorets, I.M.; Soldatov, C.A.; Tarasenko, A.S.; Wiel, van der M.J.; Botman, J.I.M.

2006-01-01

Recently opportunities of creation test facility with sub-crit. reactors controlled by accelerators of particles are actively discussed. At an initial stage of these researches it is the most expedient to use electron accelerators as cost of such facility will be much less, than at use of proton

75 FR 57385 - Internal Control Over Financial Reporting in Exchange Act Periodic Reports of Non-Accelerated Filers

Science.gov (United States)

2010-09-21

... attestation report of its registered public accounting firm on internal control over financial reporting in... definition of either an ``accelerated filer'' or a ``large accelerated filer'' under Exchange Act Rule 12b-2..., for both definitions, the issuer needs to have been subject to reporting requirements for at least...

Tailorable software architectures in the accelerator control system environment

International Nuclear Information System (INIS)

Mejuev, Igor; Kumagai, Akira; Kadokura, Eiichi

2001-01-01

Tailoring is further evolution of an application after deployment in order to adapt it to requirements that were not accounted for in the original design. End-user tailorability has been extensively researched in applied computer science from HCl and software engineering perspectives. Tailorability allows coping with flexibility requirements, decreasing maintenance and development costs of software products. In general, dynamic or diverse software requirements constitute the need for implementing end-user tailorability in computer systems. In accelerator physics research the factor of dynamic requirements is especially important, due to frequent software and hardware modifications resulting in correspondingly high upgrade and maintenance costs. In this work we introduce the results of feasibility study on implementing end-user tailorability in the software for accelerator control system, considering the design and implementation of distributed monitoring application for 12 GeV KEK Proton Synchrotron as an example. The software prototypes used in this work are based on a generic tailoring platform (VEDICI), which allows decoupling of tailoring interfaces and runtime components. While representing a reusable application-independent framework, VEDICI can be potentially applied for tailoring of arbitrary compositional Web-based applications

Accelerator operation management using objects

Energy Technology Data Exchange (ETDEWEB)

Nishimura, H.; Timossi, C.; Valdez, M.

1995-04-01

Conflicts over control of shared devices or resources in an accelerator control system, and problems that can occur due to applications performing conflicting operations, are usually resolved by accelerator operators. For these conflicts to be detected by the control system, a model of accelerator operation must be available to the system. The authors present a design for an operation management system addressing the issues of operations management using the language of Object-Oriented Design (OOD). A possible implementation using commercially available software tools is also presented.

Accelerator operation management using objects

International Nuclear Information System (INIS)

Nishimura, H.; Timossi, C.; Valdez, M.

1995-01-01

Conflicts over control of shared devices or resources in an accelerator control system, and problems that can occur due to applications performing conflicting operations, are usually resolved by accelerator operators. For these conflicts to be detected by the control system, a model of accelerator operation must be available to the system. The authors present a design for an operation management system addressing the issues of operations management using the language of Object-Oriented Design (OOD). A possible implementation using commercially available software tools is also presented

Development of an automatic frequency control system for an X-band (=9300 MHz) RF electron linear accelerator

Science.gov (United States)

Cha, Sungsu; Kim, Yujong; Lee, Byung Cheol; Park, Hyung Dal; Lee, Seung Hyun; Buaphad, Pikad

2017-05-01

KAERI is developing a 6 MeV X-band radio frequency (RF) electron linear accelerator for medical purposes. The proposed X-band accelerator consists of an e-gun, an accelerating structure, two solenoid magnets, two steering magnets, a magnetron, a modulator, and an automatic frequency control (AFC) system. The accelerating structure of the component consists of oxygen-free high-conductivity copper (OFHC). Therefore, the ambient temperature changes the volume, and the resonance frequency of the accelerating structure also changes. If the RF frequency of a 9300 MHz magnetron and the resonance frequency of the accelerating structure do not match, it can degrade the performance. That is, it will decrease the output power, lower the beam current, decrease the X-ray dose rate, increase the reflection power, and result in unstable operation of the accelerator. Accelerator operation should be possible at any time during all four seasons. To prevent humans from being exposed to radiation when it is operated, the accelerator should also be operable through remote monitoring and remote control. Therefore, the AFC system is designed to meet these requirements; it is configured based on the concept of a phase-locked loop (PLL) model, which includes an RF section, an intermediate frequency (IF) [1-3] section, and a local oscillator (LO) section. Some resonance frequency controllers use a DC motor, chain, and potentiometer to store the position and tune the frequency [4,5]. Our AFC system uses a step motor to tune the RF frequency of the magnetron. The maximum tuning turn number of our magnetron frequency tuning shaft is ten. Since the RF frequency of our magnetron is 9300±25 MHz, it gives 5 MHz (∵±25 MHz/10 turns → 50 MHz/10 turns =5 MHz/turn) frequency tuning per turn. The rotation angle of our step motor is 0.72° per step and the total step number per one rotation is 360°/0.72°=500 steps. Therefore, the tuning range per step is 10 kHz/step (=5 MHz per turn/500 steps per

Development of an automatic frequency control system for an X-band (=9300 MHz) RF electron linear accelerator

Energy Technology Data Exchange (ETDEWEB)

Cha, Sungsu, E-mail: sscha@kaeri.re.kr [Nuclear Data Center, Korea Atomic Energy Research Institute (KAERI), Daejeon 34057 (Korea, Republic of); Kim, Yujong; Lee, Byung Cheol [Nuclear Data Center, Korea Atomic Energy Research Institute (KAERI), Daejeon 34057 (Korea, Republic of); Park, Hyung Dal [Radiation Technology eXcellence(RTX), Daejeon 34025 (Korea, Republic of); Lee, Seung Hyun [Department of Energy Science, Sungkyunkwan University(SKKU), Suwon 16419 (Korea, Republic of); Buaphad, Pikad [Nuclear Data Center, Korea Atomic Energy Research Institute (KAERI), Daejeon 34057 (Korea, Republic of); Radiation Technology eXcellence(RTX), Daejeon 34025 (Korea, Republic of); Accelerator and Nuclear Fusion Physical Engineering, University of Science and Technology(UST), Daejeon 34113 (Korea, Republic of)

2017-05-21

KAERI is developing a 6 MeV X-band radio frequency (RF) electron linear accelerator for medical purposes. The proposed X-band accelerator consists of an e-gun, an accelerating structure, two solenoid magnets, two steering magnets, a magnetron, a modulator, and an automatic frequency control (AFC) system. The accelerating structure of the component consists of oxygen-free high-conductivity copper (OFHC). Therefore, the ambient temperature changes the volume, and the resonance frequency of the accelerating structure also changes. If the RF frequency of a 9300 MHz magnetron and the resonance frequency of the accelerating structure do not match, it can degrade the performance. That is, it will decrease the output power, lower the beam current, decrease the X-ray dose rate, increase the reflection power, and result in unstable operation of the accelerator. Accelerator operation should be possible at any time during all four seasons. To prevent humans from being exposed to radiation when it is operated, the accelerator should also be operable through remote monitoring and remote control. Therefore, the AFC system is designed to meet these requirements; it is configured based on the concept of a phase-locked loop (PLL) model, which includes an RF section, an intermediate frequency (IF) [1-3] section, and a local oscillator (LO) section. Some resonance frequency controllers use a DC motor, chain, and potentiometer to store the position and tune the frequency [4,5]. Our AFC system uses a step motor to tune the RF frequency of the magnetron. The maximum tuning turn number of our magnetron frequency tuning shaft is ten. Since the RF frequency of our magnetron is 9300±25 MHz, it gives 5 MHz (∵±25 MHz/10 turns → 50 MHz/10 turns =5 MHz/turn) frequency tuning per turn. The rotation angle of our step motor is 0.72° per step and the total step number per one rotation is 360°/0.72°=500 steps. Therefore, the tuning range per step is 10 kHz/step (=5 MHz per turn/500 steps per

Development of an automatic frequency control system for an X-band (=9300 MHz) RF electron linear accelerator

International Nuclear Information System (INIS)

Cha, Sungsu; Kim, Yujong; Lee, Byung Cheol; Park, Hyung Dal; Lee, Seung Hyun; Buaphad, Pikad

2017-01-01

KAERI is developing a 6 MeV X-band radio frequency (RF) electron linear accelerator for medical purposes. The proposed X-band accelerator consists of an e-gun, an accelerating structure, two solenoid magnets, two steering magnets, a magnetron, a modulator, and an automatic frequency control (AFC) system. The accelerating structure of the component consists of oxygen-free high-conductivity copper (OFHC). Therefore, the ambient temperature changes the volume, and the resonance frequency of the accelerating structure also changes. If the RF frequency of a 9300 MHz magnetron and the resonance frequency of the accelerating structure do not match, it can degrade the performance. That is, it will decrease the output power, lower the beam current, decrease the X-ray dose rate, increase the reflection power, and result in unstable operation of the accelerator. Accelerator operation should be possible at any time during all four seasons. To prevent humans from being exposed to radiation when it is operated, the accelerator should also be operable through remote monitoring and remote control. Therefore, the AFC system is designed to meet these requirements; it is configured based on the concept of a phase-locked loop (PLL) model, which includes an RF section, an intermediate frequency (IF) [1-3] section, and a local oscillator (LO) section. Some resonance frequency controllers use a DC motor, chain, and potentiometer to store the position and tune the frequency [4,5]. Our AFC system uses a step motor to tune the RF frequency of the magnetron. The maximum tuning turn number of our magnetron frequency tuning shaft is ten. Since the RF frequency of our magnetron is 9300±25 MHz, it gives 5 MHz (∵±25 MHz/10 turns → 50 MHz/10 turns =5 MHz/turn) frequency tuning per turn. The rotation angle of our step motor is 0.72° per step and the total step number per one rotation is 360°/0.72°=500 steps. Therefore, the tuning range per step is 10 kHz/step (=5 MHz per turn/500 steps per

Composite multi-modal vibration control for a stiffened plate using non-collocated acceleration sensor and piezoelectric actuator

International Nuclear Information System (INIS)

Li, Shengquan; Li, Juan; Mo, Yueping; Zhao, Rong

2014-01-01

A novel active method for multi-mode vibration control of an all-clamped stiffened plate (ACSP) is proposed in this paper, using the extended-state-observer (ESO) approach based on non-collocated acceleration sensors and piezoelectric actuators. Considering the estimated capacity of ESO for system state variables, output superposition and control coupling of other modes, external excitation, and model uncertainties simultaneously, a composite control method, i.e., the ESO based vibration control scheme, is employed to ensure the lumped disturbances and uncertainty rejection of the closed-loop system. The phenomenon of phase hysteresis and time delay, caused by non-collocated sensor/actuator pairs, degrades the performance of the control system, even inducing instability. To solve this problem, a simple proportional differential (PD) controller and acceleration feed-forward with an output predictor design produce the control law for each vibration mode. The modal frequencies, phase hysteresis loops and phase lag values due to non-collocated placement of the acceleration sensor and piezoelectric patch actuator are experimentally obtained, and the phase lag is compensated by using the Smith Predictor technology. In order to improve the vibration control performance, the chaos optimization method based on logistic mapping is employed to auto-tune the parameters of the feedback channel. The experimental control system for the ACSP is tested using the dSPACE real-time simulation platform. Experimental results demonstrate that the proposed composite active control algorithm is an effective approach for suppressing multi-modal vibrations. (paper)

Laser-driven accelerators

International Nuclear Information System (INIS)

Anon.

1982-01-01

Several devices for using laser fields have been proposed and they can be classified in three broad categories - 'far-field' accelerators (such as the principle of inverse free electron lasers), 'media' accelerators (which, for example, use the inverse Cherenkov effect or laser-controlled plasma waves), and 'near-field' accelerators (using a loaded guiding structure such as cavities or gratings). These different approaches come from the fact that a particle cannot be accelerated by the absorption of single photons (because of momentum conservation) and thus some other element has to intervene. (orig./HSI).

Slip Ratio Estimation and Regenerative Brake Control for Decelerating Electric Vehicles without Detection of Vehicle Velocity and Acceleration

Science.gov (United States)

Suzuki, Toru; Fujimoto, Hiroshi

In slip ratio control systems, it is necessary to detect the vehicle velocity in order to obtain the slip ratio. However, it is very difficult to measure this velocity directly. We have proposed slip ratio estimation and control methods that do not require the vehicle velocity with acceleration. In this paper, the slip ratio estimation and control methods are proposed without detecting the vehicle velocity and acceleration when it is decelerating. We carried out simulations and experiments by using an electric vehicle to verify the effectiveness of the proposed method.

Simulation experiment on low-level RF control for dual-harmonic acceleration at CSNS RCS

International Nuclear Information System (INIS)

Shen Sirong; Li Xiao; Zhang Chunlin; Sun Hong; Tang Jingyu

2013-01-01

The design and test of the low-level RF (LLRF) control system for the dual-harmonic acceleration at the rapid cycling synchrotron (RCS) of China Spallation Neutron Source (CSNS) at phase Ⅰ is introduced. In order to implement the mode switch from the second harmonic to the fundamental during the acceleration cycle for one of the eight RF cavities, the LLRF system for the cavity has been designed differently from the others. Several technical measures such as the opening of the control loops during the mode switch and the reclosing of two tuning circuits of the RF amplifier at different moments, have been taken. The experimental results on the testing platform based on an RF prototype show good dynamic performance of the LLRF system and prove the feasibility of dual-harmonic operation. (authors)

Complex envelope control of pulsed accelerating fields in superconducting cavities

CERN Document Server

Czarski, T

2010-01-01

A digital control system for superconducting cavities of a linear accelerator is presented in this work. FPGA (Field Programmable Gate Arrays) based controller, managed by MATLAB, was developed to investigate a novel firmware implementation. The LLRF - Low Level Radio Frequency system for FLASH project in DESY is introduced. Essential modeling of a cavity resonator with signal and power analysis is considered as a key approach to the control methods. An electrical model is represented by the non-stationary state space equation for the complex envelope of the cavity voltage driven by the current generator and the beam loading. The electromechanical model of the superconducting cavity resonator including the Lorentz force detuning has been developed for a simulation purpose. The digital signal processing is proposed for the field vector detection. The field vector sum control is considered for multiple cavities driven by one klystron. An algebraic, complex domain model is proposed for the system analysis. The c...

Control of quasi-monoenergetic electron beams from laser-plasma accelerators with adjustable shock density profile

Science.gov (United States)

Tsai, Hai-En; Swanson, Kelly K.; Barber, Sam K.; Lehe, Remi; Mao, Hann-Shin; Mittelberger, Daniel E.; Steinke, Sven; Nakamura, Kei; van Tilborg, Jeroen; Schroeder, Carl; Esarey, Eric; Geddes, Cameron G. R.; Leemans, Wim

2018-04-01

The injection physics in a shock-induced density down-ramp injector was characterized, demonstrating precise control of a laser-plasma accelerator (LPA). Using a jet-blade assembly, experiments systematically varied the shock injector profile, including shock angle, shock position, up-ramp width, and acceleration length. Our work demonstrates that beam energy, energy spread, and pointing can be controlled by adjusting these parameters. As a result, an electron beam that was highly tunable from 25 to 300 MeV with 8% energy spread (ΔEFWHM/E), 1.5 mrad divergence, and 0.35 mrad pointing fluctuation was produced. Particle-in-cell simulation characterized how variation in the shock angle and up-ramp width impacted the injection process. This highly controllable LPA represents a suitable, compact electron beam source for LPA applications such as Thomson sources and free-electron lasers.

Present state of control system of tandem accelerator in JAERI. Accidents frequently occurred in 1995 fiscal year

Energy Technology Data Exchange (ETDEWEB)

Hanashima, Susumu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1996-12-01

Tandem accelerator in JAERI (Japan Atomic Energy Research Institute) has been controlled by parallel processing control system using plural microprocessors and parallel processing programming since 1992. As the control system has been smoothly operated since beginning of its usage, many system downs have been experienced at later half of 1995. After each system down, original damage has not been found and it has been recovered by usual restarting operation. Some found remarkable defects were corrected by correction of electric circuit. As a result, frequency of the system down was decreased remarkably but its level could not be reduced to a level before occurring this phenomenon. As operation of the accelerator is preferable without control line for urgent measure, fundamental determination method is planned by controlling humidity of the control room and replacing serial highway driver with a new type producing now. (G.K.)

The Los Alamos accelerator control system data base: A generic instrumentation interface

International Nuclear Information System (INIS)

Dalesio, L.R.

1990-01-01

Controlling experimental-physics applications requires a control system that can be quickly integrated and easily modified. One aspect of the control system is the interface to the instrumentation. An instrumentation set has been chosen to implement the basic functions needed to monitor and control these applications. A data-driven interface to this instrumentation set provides the required quick integration of the control system. This type of interface is limited by its built-in capabilities. Therefore, these capabilities must provide an adequate range of functions to be of any use. The data-driven interface must support the instrumentation range requird, the events on which to read or control the instrumentation and a method for manipulating the data to calculate terms or close control loops. The database for the Los Alamos Accelerator Control System addresses these requirements. (orig.)

API manager implementation and its use for Indus accelerator control

International Nuclear Information System (INIS)

Merh, B.N.; Agrawal, R.K.; Barpande, K.; Fatnani, P.; Navathe, C.P.

2012-01-01

The control system software needed for operation of Indus accelerators is coupled to the underlying firmware and hardware of the control system by the Application Programming Interface (API) manager. In the three layered architecture of Indus control system, PVSS-II SCADA is being used at the layer-1(L1) for control and monitoring of various sub-systems. The layer-2(L2) consists of VME bus based system. The API manager plays a crucial role in interfacing the L1 and L2 of the control system. It has to interact with both the PVSS database and the L2. In order to access the PVSS database it uses the PVSS API, a C++ class library, whereas in order to access the L2 custom functions have been built. Several other custom functionalities have also been implemented. The paper presents the important aspects of the API manager like its implementation, its interface mechanism to the lower layer and features like configurability, reusable classes, multithreading capability etc. (author)

Tuners, microphonics, and control systems in superconducting accelerating structures

International Nuclear Information System (INIS)

Doolittle, L.R.

1990-01-01

Manufacturing tolerances, thermal stresses, acoustic noise, and cooling fluid pressure fluctuations all conspire to make the field in the cavity not precisely what the accelerator physicist has in mind. Tuners and control systems are the tools used to fight back: they regulate the field in the cavity to the desired magnitude and phase. Amplitude and phase stabilities are usually of greater concern in superconducting cavities than in copper cavities. The key to achieving a stable gradient and phase is feedback. A probe must be placed in the cavity itself to sense the present cavity status. Electronic control is then given the responsibility to correct for any measured disturbance. The electronic modulation of forward power has been implemented in a number of ways. Perhaps the easiest implementation to understand has two separate control loops, one for amplitude and one for phase (phase-amplitude loops). Other major electronic control devices include complex phasor modulator (CPM-amplitude loops), vector loop, and variable reactance. 'Slow' tuners are used when the tuning range of the 'fast' tuner plus electronic tuning is not enough to compensate for unpredictability or drift in the static frequency setting. (N.K.)

The Datacon Master -- Renovation of a Datacon field bus communications system for accelerator control

International Nuclear Information System (INIS)

Kerner, T.M.

1995-01-01

The Datacon system is a serial coaxial transformer isolated communication field bus system used to control and monitor accelerator remote devices. The Datacon field bus has been a BNL accelerator standard since its initial use in 1965. A single Datacon field bus supports up to 256 devices on a multidrop RG62A/U coaxial cable with up to 33 devices or 2,000 feet between repeaters or buffered branches. The forcing factor to renovate was the inability to repair the aging PDP-8E and PDP10 computers. The maintenance on this aging system was costly and the large number of accelerator devices dependent on the Datacon system could not be converted in a reasonable period of time to a new modern field bus. A commercial VMEbus host CPU mated with a custom designed VMEbus SBC event driven serial communications engine featuring a superscaler RISC 32-bit Intel i960 CPU met the design challenge. The commercial VMEbus host runs the VxWorks real-time operating system and connects to UNIX workstations over a Ethernet LAN. The V110 Datacon Master is the custom designed front end computer that integrates an accelerator event time line system with accelerator devices for up to 8 ppm users adding new capabilities

CAS CERN Accelerator School: Advanced accelerator physics. Proceedings. Vol. 2

International Nuclear Information System (INIS)

Turner, S.

1987-01-01

This advanced course on general accelerator physics is the second of the biennial series given by the CERN Accelerator School and follows on from the first basic course given at Gif-sur-Yvette, Paris, in 1984. Stress is placed on the mathematical tools of Hamiltonian mechanics and the Vlasov and Fokker-Planck equations, which are widely used in accelerator theory. The main topics treated in this present work include: nonlinear resonances, chromaticity, motion in longitudinal phase space, growth and control of longitudinal and transverse beam emittance, space-charge effects and polarization. The seminar programme treats some specific accelerator techniques, devices, projects and future possibilities. (orig.)

FPGA Mezzanine Cards for CERN’s Accelerator Control System

CERN Document Server

Alvarez, P R; Lewis, J; Serrano, J; Wlostowski, T

2009-01-01

Field Programmable Gate Arrays (FPGAs) have become a key player in modern real time control systems. They offer determinism, simple design, high performance and versatility. A typical hardware architecture consists of an FPGA interfaced with a control bus and a variable number of digital IOs, ADCs and DACs depending on the application. Until recently the low-cost hardware paradigm has been using mezzanines containing a front end interface plus custom logic (typically an FPGA) and a local bus that interfaces the mezzanine to a carrier. As FPGAs grow in size and shrink in price, hardware reuse, testability and bus access speed could be improved if the user logic is moved to the carrier. The new FPGA Mezzanine Card (FMC) Vita 57 standard is a good example of this new paradigm. In this paper we present a standard kit of FPGA carriers and IO mezzanines for accelerator control. Carriers form factors will be VME, PCI and PCIe. The carriers will feature White Rabbit support for accurate synchronization of distributed...

Promoting a Positive Middle School Transition: A Randomized-Controlled Treatment Study Examining Self-Concept and Self-Esteem.

Science.gov (United States)

Coelho, Vitor Alexandre; Marchante, Marta; Jimerson, Shane R

2017-03-01

The middle school transition is a salient developmental experience impacting adolescents around the world. This study employed a randomized-controlled treatment design, with randomization at the school level, to investigate the impact of a school adjustment program for middle school transition and potential gender differences. Participants included 1147 students (M age  = 9.62; SD = 0.30, 45.7 % girls), who were assessed at four time points during the transition, regarding five dimensions of self-concept (academic, social, emotional, physical and family) and self-esteem. Parallel growth curves were employed to analyze the evolution of self-concept. Following the transition to middle school, students reported lower levels of self-concept (academic, emotional and physical) and self-esteem, while participation in the intervention led to increases in self-esteem and gains in social self-concept. No gender differences were found. These results provide preliminary evidence supporting such interventions in early middle school transitions.

The SSC field bus: A high-performance control system front end concentrator for 'slow' accelerator controls

International Nuclear Information System (INIS)

Haenni, D.R.; Saltmarsh, C.G.; Lue, H.C.; Hunt, S.M.

1991-01-01

The SSC control system must support a large number of 'slow' or industrial type control points. A front-end system is described which could serve as both a data concentrator and a distributed process controller for these points. Unlike many distributed control systems, this front end is designed to provide strong support for centralized controls. The live parameter data base in the central system can be updated at a rate which is fast compared to that usually needed for process control loops. Portions of this data base can be optionally replicated in regional computers to provide both local control stations and distributed control loops. In addition to the global and regional levels the system also allows the distribution of loops to the local I/O crate level. A possible implementation of this system is under development which is based on industrial standard STD-Bus for accelerator hardware interfacing, time domain multiplexing (TDM) for communications transport, and a form of reflective memory for the back-end interface to the rest of the control system

Experience in using workstations as hosts in an accelerator control environment

International Nuclear Information System (INIS)

Abola, A.; Casella, R.; Clifford, T.; Hoff, L.; Katz, R.; Kennell, S.; Mandell, S.; McBreen, E.; Weygand, D.P.

1987-03-01

A new control system has been used for light ion acceleration at the Alternating Gradient Synchrotron (AGS). The control system uses Apollo workstations in the dual role of console hardware computer and controls system host. It has been found that having a powerful dedicated CPU with a demand paging virtual memory OS featuring strong interprocess communication, mapped memory shared files, shared code, and multi-window capabilities, allows us to provide an efficient operation environment in which users may view and manage several control processes simultaneously. The same features which make workstations good console computers also provide an outstanding platform for code development. The software for the system, consisting of about 30K lines of ''C'' code, was developed on schedule, ready for light ion commissioning. System development is continuing with work being done on applications programs

Experience in using workstations as hosts in an accelerator control environment

International Nuclear Information System (INIS)

Abola, A.; Casella, R.; Clifford, T.; Hoff, L.; Katz, R.; Kennell, S.; Mandell, S.; McBreen, E.; Weygand, D.P.

1987-01-01

A new control system has been used for light ion acceleration at the Alternating Gradient Synchrotron (AGS). The control system uses Apollo workstations in the dual role of console hardware computer and controls system host. It has been found that having a powerful dedicated CPU with a demand paging virtual memory OS featuring strong interprocess communication, mapped memory shared files, shared code, and multi-window capabilities, allows us to provide an efficient operation environment in which users may view and manage several control processes simultaneously. The same features which make workstations good console computers also provide an outstanding platform for code development. The software for the system, consisting of about 30K lines of ''C'' code, was developed on schedule, ready for light ion commissioning. System development is continuing with work being done on applications programs

FMIT accelerator

International Nuclear Information System (INIS)

Armstrong, D.D.

1983-01-01

A 35-MeV 100-mA cw linear accelerator is being designed by Los Alamos for use in the Fusion Materials Irradiation Test (FMIT) Facility. Essential to this program is the design, construction, and evaluation of performance of the accelerator's injector, low-energy beam transport, and radio-frequency quadrupole sections before they are shipped to the facility site. The installation and testing of some of these sections have begun as well as the testing of the rf, noninterceptive beam diagnostics, computer control, dc power, and vacuum systems. An overview of the accelerator systems and the performance to date is given

Micro ball lightning and its accelerator proposed to control natural phenomena

International Nuclear Information System (INIS)

Matsumoto, Taka-aki

2002-01-01

Micro Ball Lightning (BL) was recently discovered in laboratory. It was also observed during natural phenomena such as volcanic eruption and earthquake. This paper described a brief review of micro BL observed in laboratory as well as during two natural phenomena. Being based on a hypothesis of that those natural phenomena could have been caused by explosive reactions of micro BL, a potential accelerator of micro BL was proposed to control the natural phenomena. (author)

Prototype phase and amplitude feedback-control systems for the FMIT accelerator

International Nuclear Information System (INIS)

Fazio, M.V.; Patton, R.D.

1983-01-01

The phase and amplitude feedback-control systems for the Fusion Materials irradiation Test (FMIT) accelerator have been successfully prototyped and tested. The testing was performed at low power with two 100-W rf systems driving a high-Q resonant cavity at 80 MHz. The control systems can maintain the cavity field amplitude to within +-1% and the phase to within +-1 0 of the set-point values. When there are multiple rf systems independently driving a resonant cavity through individual drive loops, amplitude matching and proper phasing between the outputs of each rf system are essential for proper system operation. Experimental results are presented

Investigating the feasibility of temperature-controlled accelerated drug release testing for an intravaginal ring.

Science.gov (United States)

Externbrink, Anna; Clark, Meredith R; Friend, David R; Klein, Sandra

2013-11-01

The objective of the present study was to investigate if temperature can be utilized to accelerate drug release from Nuvaring®, a reservoir type intravaginal ring based on polyethylene vinyl acetate copolymer that releases a constant dose of contraceptive steroids over a duration of 3 weeks. The reciprocating holder apparatus (USP 7) was utilized to determine real-time and accelerated etonogestrel release from ring segments. It was demonstrated that drug release increased with increasing temperature which can be attributed to enhanced drug diffusion. An Arrhenius relationship of the zero-order release constants was established, indicating that temperature is a valid parameter to accelerate drug release from this dosage form and that the release mechanism is maintained under these accelerated test conditions. Accelerated release tests are particularly useful for routine quality control to assist during batch release of extended release formulations that typically release the active over several weeks, months or even years, since they can increase the product shelf life. The accelerated method should therefore be able to discriminate between formulations with different release characteristics that can result from normal manufacturing variance. In the case of Nuvaring®, it is well known that the process parameters during the extrusion process strongly influence the polymeric structure. These changes in the polymeric structure can affect the permeability which, in turn, is reflected in the release properties. Results from this study indicate that changes in the polymeric structure can lead to a different temperature dependence of the release rate, and as a consequence, the accelerated method can become less sensitive to detect changes in the release properties. When the accelerated method is utilized during batch release, it is therefore important to take this possible restriction into account and to evaluate the accelerated method with samples from non

Ant colony method to control variance reduction techniques in the Monte Carlo simulation of clinical electron linear accelerators

International Nuclear Information System (INIS)

Garcia-Pareja, S.; Vilches, M.; Lallena, A.M.

2007-01-01

The ant colony method is used to control the application of variance reduction techniques to the simulation of clinical electron linear accelerators of use in cancer therapy. In particular, splitting and Russian roulette, two standard variance reduction methods, are considered. The approach can be applied to any accelerator in a straightforward way and permits, in addition, to investigate the 'hot' regions of the accelerator, an information which is basic to develop a source model for this therapy tool

Acceleration of laser-injected electron beams in an electron-beam driven plasma wakefield accelerator

International Nuclear Information System (INIS)

Knetsch, Alexander

2018-03-01

Plasma wakefields deliver accelerating fields that are approximately a 100 times higher than those in conventional radiofrequency or even superconducting radiofrequency cavities. This opens a transformative path towards novel, compact and potentially ubiquitous accelerators. These prospects, and the increasing demand for electron accelerator beamtime for various applications in natural, material and life sciences, motivate the research and development on novel plasma-based accelerator concepts. However, these electron beam sources need to be understood and controlled. The focus of this thesis is on electron beam-driven plasma wakefield acceleration (PWFA) and the controlled injection and acceleration of secondary electron bunches in the accelerating wake fields by means of a short-pulse near-infrared laser. Two laser-triggered injection methods are explored. The first one is the Trojan Horse Injection, which relies on very good alignment and timing control between electron beam and laser pulse and then promises electron bunches with hitherto unprecedented quality as regards emittance and brightness. The physics of electron injection in the Trojan Horse case is explored with a focus on the final longitudinal bunch length. Then a theoretical and numerical study is presented that examines the physics of Trojan Horse injection when performed in an expanding wake generated by a smooth density down-ramp. The benefits are radically decreased drive-electron bunch requirements and a unique bunch-length control that enables longitudinal electron-bunch shaping. The second laser-triggered injection method is the Plasma Torch Injection, which is a versatile, all-optical laser-plasma-based method capable to realize tunable density downramp injection. At the SLAC National Laboratory, the first proof-of-principle was achieved both for Trojan Horse and Plasma Torch injection. Setup details and results are reported in the experimental part of the thesis along with the commissioning

Proactive control in early and middle childhood: An ERP study

Directory of Open Access Journals (Sweden)

Sarah Elke

2017-08-01

Full Text Available Children experience important cognitive control improvements in the transition to school. This study examined 4–5-year-olds’ (n = 17 and 7–8-year-olds’ (n = 22 ability to proactively deploy cognitive control. Children performed a cued task-switching paradigm presenting them with a cue indicating which attribute, color or shape, they should use to sort the upcoming stimulus. Following both cue and stimulus, we analyzed two event-related potentials: the P2 and P3, positive peaks reflecting sensory and attentional components of cognitive control, respectively. Following the cue, we also analyzed a positive slow-wave, indexing working memory engagement. We predicted that on switch trials, which required switching tasks, proactive control would result in larger cue-P3 amplitudes, reflecting recognition of the need to switch, and larger slow-wave amplitudes, reflecting maintenance of the new task-sets over the post-cue delay. This pattern was observed in both age groups. At the stimulus, in switch trials, both age groups had shorter stimulus-P2 latencies, consistent with processing facilitation. These results suggest that both 4–5- and 7–8-year-olds engaged cognitive control proactively. Older children, however, demonstrated better performance and larger cue-P2 amplitudes, suggesting more effective proactive control engagement in middle childhood.

Accelerators for energy

International Nuclear Information System (INIS)

Inoue, Makoto

2000-01-01

A particle accelerator is a device to consume energy but not to produce it. Then, the titled accelerator seems to mean an accelerator for using devices related to nuclear energy. For an accelerator combined to nuclear fissionable fuel, neutron sources are D-T type, (gamma, n) reaction using electron beam type spallation type, and so forth. At viewpoints of powers of incident beam and formed neutron, a spallation type source using high energy proton is told to be effective but others have some advantages by investigation on easy operability, easy construction, combustion with target, energy and directivity of neutron, and so forth. Here were discussed on an accelerator for research on accelerator driven energy system by dividing its researching steps, and on kind, energy, beam intensity, and so forth of an accelerator suitable for it. And, space electric charge effect at beam propagation direction controlled by beam intensity of cyclotron was also commented. (G.K.)

Inflammatory bowel disease in children of middle eastern descent.

Science.gov (United States)

Naidoo, Christina Mai Ying; Leach, Steven T; Day, Andrew S; Lemberg, Daniel A

2014-01-01

Increasing rates of inflammatory bowel disease (IBD) are now seen in populations where it was once uncommon. The pattern of IBD in children of Middle Eastern descent in Australia has never been reported. This study aimed to investigate the burden of IBD in children of Middle Eastern descent at the Sydney Children's Hospital, Randwick (SCHR). The SCHR IBD database was used to identify patients of self-reported Middle Eastern ethnicity diagnosed between 1987 and 2011. Demographic, diagnosis, and management data was collected for all Middle Eastern children and an age and gender matched non-Middle Eastern IBD control group. Twenty-four patients of Middle Eastern descent were identified. Middle Eastern Crohn's disease patients had higher disease activity at diagnosis, higher use of thiopurines, and less restricted colonic disease than controls. Although there were limitations with this dataset, we estimated a higher prevalence of IBD in Middle Eastern children and they had a different disease phenotype and behavior compared to the control group, with less disease restricted to the colon and likely a more active disease course.

Simultaneous multislice echo planar imaging with blipped controlled aliasing in parallel imaging results in higher acceleration: a promising technique for accelerated diffusion tensor imaging of skeletal muscle

OpenAIRE

Filli, Lukas; Piccirelli, Marco; Kenkel, David; Guggenberger, Roman; Andreisek, Gustav; Beck, Thomas; Runge, Val M; Boss, Andreas

2015-01-01

PURPOSE The aim of this study was to investigate the feasibility of accelerated diffusion tensor imaging (DTI) of skeletal muscle using echo planar imaging (EPI) applying simultaneous multislice excitation with a blipped controlled aliasing in parallel imaging results in higher acceleration unaliasing technique. MATERIALS AND METHODS After federal ethics board approval, the lower leg muscles of 8 healthy volunteers (mean [SD] age, 29.4 [2.9] years) were examined in a clinical 3-T magnetic ...

Flame acceleration of hydrogen - air - diluent mixtures at middle scale using ENACCEF: experiments and modelling

International Nuclear Information System (INIS)

Fabrice Malet; Nathalie Lamoureux; Nabiha Djebaili-Chaumeix; Claude-Etienne Paillard; Pierre Pailhories; Jean-Pierre L'heriteau; Bernard Chaumont; Ahmed Bentaib

2005-01-01

Full text of publication follows: In the case of hypothetic severe accident on light water nuclear reactor, hydrogen would be produced during reactor core degradation and released to the reactor building which could subsequently raise a combustion hazard. A local ignition of the combustible mixture would give birth initially to a slow flame which can be accelerated due to turbulence. Depending on the geometry and the premixed combustible mixture composition, the flame can accelerate and for some conditions transit to detonation or be quenched after a certain distance. The flame acceleration is responsible for the generation of high pressure loads that could damage the reactor's building. Moreover, geometrical configuration is a major factor leading to flame acceleration. Thus, recording experimental data notably on mid-size installations is required for the numeric simulations validation before modelling realistic scales. The ENACCEF vertical facility is a 6 meters high acceleration tube aimed at representing steam generator room leading to containment dome. This setup can be equipped with obstacles of different blockage ratios and shapes in order to obtain an acceleration of the flame. Depending on the geometrical characteristics of these obstacles, different regimes of the flame propagation can be achieved. The mixture composition's influence on flame velocity and acceleration has been investigated. Using a steam physical-like diluent (40% He - 60% CO 2 ), influence of dilution on flame speed and acceleration has been investigated. The flame front has also been recorded with ultra fast ombroscopy visualization, both in the tube and in dome's the entering. The flame propagation is computed using the TONUS code. Based on Euler's equation solving code using structured finite volumes, it includes the CREBCOM flames modelling and simulates the hydrogen/air turbulent flame propagation, taking into account 3D complex geometry and reactants concentration gradients. Since

Notes on Laser Acceleration

International Nuclear Information System (INIS)

Tajima, T.

2008-01-01

This note intends to motivate our effort toward the advent of new methods of particle acceleration, utilizing the fast rising laser technology. By illustrating the underlying principles in an intuitive manner and thus less jargon-clad fashion, we seek a direction in which we shall be able to properly control and harness the promise of laser acceleration. First we review the idea behind the laser wakefield. We then go on to examine ion acceleration by laser. We examine the sheath acceleration in particular and look for the future direction that allows orderly acceleration of ions in high energies

Control, timing, and data acquisition for the Argonne Wakefield Accelerator (AWA)

International Nuclear Information System (INIS)

Schoessow, P.; Ho, C.; Power, J.; Chojnacki, E.

1993-01-01

The AWA is a new facility primarily designed for wakefield acceleration experiments at the 100 MV/m scale, which incorporates a high current linac and rf photocathode electron source, a low emittance rf electron gun for witness beam generation, and associated beamlines and diagnostics. The control system is based on VME and CA-MAC electronics interfaced to a high performance work-station and provides some distributed processing capability. In addition to the control of linac rf, laser optics, and beamlines, the system is also used for acquisition of video data both from luminescent beam position monitors and from streak camera pulse length diagnostics. Online image feature extraction will permit wakefields to be computed during the course of data taking. The linac timing electronics and its interface to the control system is described

Inhibitory control and moral emotions: relations to reparation in early and middle childhood.

Science.gov (United States)

Colasante, Tyler; Zuffianò, Antonio; Bae, Na Young; Malti, Tina

2014-01-01

This study examined links between inhibitory control, moral emotions (sympathy and guilt), and reparative behavior in an ethnically diverse sample of 4- and 8-year-olds (N = 162). Caregivers reported their children's reparative behavior, inhibitory control, and moral emotions through a questionnaire, and children reported their guilt feelings in response to a series of vignettes depicting moral transgressions. A hypothesized meditation model was tested with inhibitory control relating to reparative behavior through sympathy and guilt. In support of this model, results revealed that high levels of inhibitory control were associated with high levels of reparative behavior through high levels of sympathy and guilt. However, the mediation of inhibitory control to reparation through guilt was significant for 4-year-olds only. Results are discussed in relation to the temperamental, regulatory, and affective-moral precursors of reparative behavior in early and middle childhood.

Ant colony method to control variance reduction techniques in the Monte Carlo simulation of clinical electron linear accelerators

Energy Technology Data Exchange (ETDEWEB)

Garcia-Pareja, S. [Servicio de Radiofisica Hospitalaria, Hospital Regional Universitario ' Carlos Haya' , Avda. Carlos Haya, s/n, E-29010 Malaga (Spain)], E-mail: garciapareja@gmail.com; Vilches, M. [Servicio de Fisica y Proteccion Radiologica, Hospital Regional Universitario ' Virgen de las Nieves' , Avda. de las Fuerzas Armadas, 2, E-18014 Granada (Spain); Lallena, A.M. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada (Spain)

2007-09-21

The ant colony method is used to control the application of variance reduction techniques to the simulation of clinical electron linear accelerators of use in cancer therapy. In particular, splitting and Russian roulette, two standard variance reduction methods, are considered. The approach can be applied to any accelerator in a straightforward way and permits, in addition, to investigate the 'hot' regions of the accelerator, an information which is basic to develop a source model for this therapy tool.

On the Neutron Kinetics and Control of Accelerator-Driven Systems

International Nuclear Information System (INIS)

Cacuci, D.G.

2004-01-01

This work addresses fundamental aspects of the time- and space-dependent behavior of an Accelerator-Driven Subcritical Core System (ADS) and presents a paradigm ADS neutron kinetics model that is solved exactly. Thus, this paradigm model can serve for benchmarking two- and/or three-dimensional computational tools. Furthermore, this work also proposes a global optimal control theory framework for the operation and control of an ADS. This framework encompasses conceptually the time- and space-dependent behavior of the ADS coupled neutron kinetics/thermal-hydraulic balance equations and aims at the optimal control of ADS operational objectives, which would include minimization of local flux disturbances, load and source following, etc. Importantly, this new conceptual framework makes no use of a 'fictitious ADS steady state' and yields the correct and complete (i.e., including sources) adjoint equations, without leaving any room for ambiguities. Thus, this new conceptual framework provides a natural basis for developing new computational methods and corresponding verification experiments specifically tailored for the control and operation of ADS

Flexusi Interface Builder For Computer Based Accelerator Monitoring And Control System

CERN Document Server

Kurakin, V G; Kurakin, P V

2004-01-01

We have developed computer code for any desired graphics user interface designing for monitoring and control system at the executable level. This means that operator can build up measurement console consisting of virtual devices before or even during real experiment without recompiling source file. Such functionality results in number of advantages comparing with traditional programming. First of all any risk disappears to introduce bug into source code. Another important thing is the fact the both program developers and operator staff do not interface in developing ultimate product (measurement console). Thus, small team without detailed project can design even very complicated monitoring and control system. For the reason mentioned below, approach suggested is especially helpful for large complexes to be monitored and control, accelerator being among them. The program code consists of several modules, responsible for data acquisition, control and representation. Borland C++ Builder technologies based on VCL...

Upgrading the control system for the Accelerators at the Svedberg Laboratory

International Nuclear Information System (INIS)

Gajewski, K.J.; Thuresson, L.; Johansson, O.

1992-01-01

Two accelerators at The Svedberg Laboratory in Uppsala, the Gustaf Werner cyclotron and the CELSIUS ring, will get a new control system. At present both the cyclotron and the ring have their own control systems based on S99 and PDP-11 minicomputers respectively. There are also a number of subsystems which are controlled separately from the stand-alone PC based consoles (ECR ion source, electron cooler, vacuum system). The goal of the rejuvenation is to integrate all existing control systems and provide the new system with an uniform operators interface based on workstations. The obsolete S99 microcomputers will be substituted with a VME system and all subsystems will be connected to the Ethernet. The upgrade strategy enabling the transformation of the system without any long shut-down period is discussed. Hardware and software planned for the upgrade is presented together with a discussion of expected problems. (author)

A study of an electron gun controlled with a meshless grid for a linear accelerator

International Nuclear Information System (INIS)

Homma, Akira; Nakata, Katsuhide; Sawamura, Teruko; Narita, Masakuni

1996-01-01

An electron gun for a linear accelerator with a control grid of meshless electrode (meshless grid) is expected to overcome some disadvantages of beam quality using an ordinary mesh grid. A gun of this type was designed and its characteristics were numerically analyzed. The simulation program code Egn2 with a boundary setting routine POLYGON was used. The result indicated that the grid can control the beam launched from the cathode to the anode electrode. It also indicated the Ip-Vp and Ip-Vp characteristics which are different from an ordinary triode gun with a mesh-grid. The mutual conductance gm of 0.4[mS], the maximum average current of 1.6[A] and cut-off voltage -200[V] were obtained under a condition of 200[kV] acceleration voltage. (author)

Accelerator shielding benchmark problems

International Nuclear Information System (INIS)

Hirayama, H.; Ban, S.; Nakamura, T.

1993-01-01

Accelerator shielding benchmark problems prepared by Working Group of Accelerator Shielding in the Research Committee on Radiation Behavior in the Atomic Energy Society of Japan were compiled by Radiation Safety Control Center of National Laboratory for High Energy Physics. Twenty-five accelerator shielding benchmark problems are presented for evaluating the calculational algorithm, the accuracy of computer codes and the nuclear data used in codes. (author)

Increasing evidence for the efficacy of tobacco control mass media communication programming in low- and middle-income countries.

Science.gov (United States)

Mullin, Sandra; Prasad, Vinayak; Kaur, Jagdish; Turk, Tahir

2011-08-01

Antitobacco mass media campaigns have had good success at changing knowledge, attitudes, and behaviors with respect to smoking in high-income countries provided they are sustained. Mass media campaigns should be a critical component of tobacco control programs in low- and lower-middle-income countries. Mounting evidence shows that graphic campaigns and those that evoke negative emotions run over long periods of time have achieved the most influence. These types of campaigns are now being implemented in low- and middle-income countries. The authors provide 3 case studies of first-ever graphic warning mass media campaigns in China, India, and Russia, 3 priority high-burden countries in the global Bloomberg Initiative to Reduce Tobacco Use. In each of these countries, message testing of core messages provided confidence in messages, and evaluations demonstrated message uptake. The authors argue that given the initial success of these campaigns, governments in low- and middle-income countries should consider resourcing and sustaining these interventions as key components of their tobacco control strategies and programs.

Distributed Active Traction Control System Applied to the RoboCup Middle Size League

Directory of Open Access Journals (Sweden)

José Almeida

2013-10-01

Full Text Available This work addresses the problem of traction control in mobile wheeled robots in the particular case of the RoboCup Middle Size League (MSL. The slip control problem is formulated using simple friction models for ISePorto Team Robots with a differential wheel configuration. Traction was also characterized experimentally in the MSL scenario for relevant game events. This work proposes a hierarchical traction control architecture which relies on local slip detection and control at each wheel, with relevant information being relayed to a higher level responsible for global robot motion control. A dedicated one axis control embedded hardware subsystem allowing complex local control, high frequency current sensing and odometric information procession was developed. This local axis control board is integrated in a distributed system using CAN bus communications. The slipping observer was implemented in the axis control hardware nodes integrated in the ISePorto Robots and was used to control and detect loss of traction. An external vision system was used to perform a qualitative analysis of the slip detection and observer performance results are presented.

AI systems approach in particle accelerators

International Nuclear Information System (INIS)

Kataria, S.K.; Bhagwat, P.V.; Kori, S.A.

1992-01-01

The large particle accelerators machines like pelletron accelerator at Tata Institute of Fundamental Research (T.I.F.R) have several levels of controls with operators responsible for overall global control decisions and closed loop feedback controllers for relatively small subsystems of the machines. As the accelerator machines are becoming more complicated and the requirements more stringent, there is a need to provide the operators with an artificial intelligence (AI) system to aid in the tuning the machine and in failure diagnosis. There are few major areas in the pelletron operation, which can be done more efficiently using AI systems approach so that useful beam is available for much more time: 1) Accelerator Conditioning, 2) Accelerator Tuning, and 3) Maintaining the Tune beams. The feasibility study for using expert system for above areas and also for safety evaluation of the various subsystems is carried out. (author). 10 refs., 4 figs

Mitigation of ground motion effects in linear accelerators via feed-forward control

Directory of Open Access Journals (Sweden)

J. Pfingstner

2014-12-01

Full Text Available Ground motion is a severe problem for many particle accelerators, since it excites beam oscillations, which decrease the beam quality and create beam-beam offset (at colliders. Orbit feedback systems can only compensate ground motion effects at frequencies significantly smaller than the beam repetition rate. In linear colliders, where the repetition rate is low, additional counter measures have to be put in place. For this reason, a ground motion mitigation method based on feed-forward control is presented in this paper. It has several advantages compared to other techniques (stabilization systems and intratrain feedback systems such as cost reduction and potential performance improvement. An analytical model is presented that allows the derivation of hardware specification and performance estimates for a specific accelerator and ground motion model. At the Accelerator Test Facility (ATF2, ground motion sensors have been installed to verify the feasibility of important parts of the mitigation strategy. In experimental studies, it has been shown that beam excitations due to ground motion can be predicted from ground motion measurements on a pulse-to-pulse basis. Correlations of up to 80% between the estimated and measured orbit jitter have been observed. Additionally, an orbit jitter source was identified and has been removed, which halved the orbit jitter power at ATF2 and shows that the feed-forward scheme is also very useful for the detection of installation issues. We believe that the presented mitigation method has the potential to reduce costs and improve the performance of linear colliders and potentially other linear accelerators.

Acceleration control system for semi-active in-car crib with joint application of regular and inverted pendulum mechanisms

International Nuclear Information System (INIS)

Kawashima, T

2016-01-01

To reduce the risk of injury to an infant in an in-car crib (or in a child safety bed) collision shock during a car crash, it is necessary to maintain a constant force acting on the crib below a certain allowable value. To realize this objective, we propose a semi-active in-car crib system with the joint application of regular and inverted pendulum mechanisms. The arms of the proposed crib system support the crib like a pendulum while the pendulum system itself is supported like an inverted pendulum by the arms. In addition, the friction torque of each arm is controlled using a brake mechanism that enables the proposed in-car crib to decrease the acceleration of the crib gradually and maintain it around the target value. This system not only reduces the impulsive force but also transfers the force to the infant's back using a spin control system, i.e., the impulse force acts is made to act perpendicularly on the crib. The spin control system was developed in our previous work. This work focuses on the acceleration control system. A semi-active control law with acceleration feedback is introduced, and the effectiveness of the system is demonstrated using numerical simulation and model experiment. (paper)

Acceleration control system for semi-active in-car crib with joint application of regular and inverted pendulum mechanisms

Science.gov (United States)

Kawashima, T.

2016-09-01

To reduce the risk of injury to an infant in an in-car crib (or in a child safety bed) collision shock during a car crash, it is necessary to maintain a constant force acting on the crib below a certain allowable value. To realize this objective, we propose a semi-active in-car crib system with the joint application of regular and inverted pendulum mechanisms. The arms of the proposed crib system support the crib like a pendulum while the pendulum system itself is supported like an inverted pendulum by the arms. In addition, the friction torque of each arm is controlled using a brake mechanism that enables the proposed in-car crib to decrease the acceleration of the crib gradually and maintain it around the target value. This system not only reduces the impulsive force but also transfers the force to the infant's back using a spin control system, i.e., the impulse force acts is made to act perpendicularly on the crib. The spin control system was developed in our previous work. This work focuses on the acceleration control system. A semi-active control law with acceleration feedback is introduced, and the effectiveness of the system is demonstrated using numerical simulation and model experiment.

Collective acceleration investigations with the ionization front accelerator

International Nuclear Information System (INIS)

Olson, C.L.; Poukey, J.W.; VanDevender, J.P.; Owyoung, A.; Pearlman, J.S.

1977-01-01

Part I of a three part program to demonstrate feasibility of the Ionization Front Accelerator (IFA) has been completed and is successful. Experiments describing intense relativistic electron beam (IREB) propagation in Cs are reported. The threshold pressure for electron beam ionization of Cs is found to agree with earlier theoretical predictions. These results experimentally establish Cs as a feasible working gas for the IFA. Numerical simulation results are also reported which demonstrate controlled potential well motion and collective ion acceleration with the IFA

Development of the accelerating system

Energy Technology Data Exchange (ETDEWEB)

Jang, Jiho; Kwon, H. J.; Kim, D. I.; Kim, H. S.; Ryu, J. Y.; Park, B. S.; Seol, K. T.; Yun, S. P.; Song, Y. G.; Cho, Y. S.

2013-02-15

One of the main purposes of the 'Development of the Accelerating System' is developing a 100-MeV proton linac which accelerate proton beams from 20 MeV to 100 MeV by using 7 DTL (drift tube linac) tanks. Two of them were finished in the 2-nd stage of the project. The remaining part was also successfully fabricated and installed at Gyeongju site of KAERI. The MEBT is an essential component to extract and supply 20-MeV proton beams to users, and to match proton beams to the next accelerating structure for 100-MeV acceleration. The development of the MEBT has successfully finished. The project also developed the digital LLRF (low level RF) system which control the accelerating field within 1% in magnitude and 1 degree in phase. This system has been successfully tested in the 20-MeV linac operation at Daejeon site of KAERI. The modified version of the digital LLRF system will be used in the 100-MeV linac operation. The project also developed the beam diagnostic system. They are the strip-line type beam position monitor (BPM), the beam current monitor (CT), the beam loss monitor (BLM), and the emittance measurement system. They are used to measure the characteristics of the 20-MeV proton beams. The project also developed the EPIC-based control system. It is used to monitor the status of the accelerator and components, and to remotely control accelerator components. It has been used and modified in the 20-MeV linac operation. The modified version of the LLRF, diagnostics and control systems will be used in 100-MeV linac operation.

Data acquisition, control, and analysis for the Argonne Advanced Accelerator Test Facility (AATF)

International Nuclear Information System (INIS)

Schoessow, P.

1989-01-01

The AATF has been used to study wakefield acceleration and focusing in plasmas and rf structures. A PC-based system is described which incorporates the functions of beamline control and acquisition, storage, and preliminary analysis of video images from luminescent screen beam diagnostics. General features of the offline analysis of wakefield data are also discussed. 4 refs., 3 figs

Converging-barrel plasma accelerator

International Nuclear Information System (INIS)

Paine, T.O.

1971-01-01

The invention comprises a device for generating and accelerating plasma to extremely high velocity, while focusing the plasma to a decreasing cross section for attaining a very dense high-velocity plasma burst capable of causing nuclear fusion reactions. A converging coaxial accelerator-electrode configuration is employed with ''high-pressure'' gas injection in controlled amounts to achieve acceleration by deflagration and focusing by the shaped electromagnetic fields. (U.S.)

CONFERENCE: Computers and accelerators

Energy Technology Data Exchange (ETDEWEB)

Anon.

1984-01-15

In September of last year a Conference on 'Computers in Accelerator Design and Operation' was held in West Berlin attracting some 160 specialists including many from outside Europe. It was a Europhysics Conference, organized by the Hahn-Meitner Institute with Roman Zelazny as Conference Chairman, postponed from an earlier intended venue in Warsaw. The aim was to bring together specialists in the fields of accelerator design, computer control and accelerator operation.

Local control of T3 carcinomas after accelerated fractionation: a look at the 'gap'

International Nuclear Information System (INIS)

Wang, C.C.; Efird, Jimmy; Nakfoor, Bruce; Martins, Patricia

1996-01-01

Purpose: To study the effects of midcourse treatment break or gaps related to the local control of T3 carcinoma of the oropharynx and larynx following accelerated hyperfractionated radiation therapy. Methods and Materials: All patients were treated at the Massachusetts General Hospital from 1979 through 1994 with treatment consisting of 1.6 Gy per fraction, two fractions a day for the treatment of T3 carcinoma of the oropharynx and larynx. They were entered in the head and neck data base. Their treatment dates, treatment breaks, and doses vs. local control were analyzed and compared. A p-value of 0.05 was considered statistically significant. Results: A total of 162 patients were available for review. Due to the acute severe mucosal effects, most of the patients required a midcourse pause or 'break' after a dose of 38.4-48 Gy before treatment could be resumed and completed. The data indicate that (a) prolongation of the treatment gap for more than 14 days, (b) total treatment course longer than 45 days, (c) total dose less than 67 Gy, and (d) male gender adversely affected local control. In spite of the gaps, the female patients with advanced carcinomas enjoyed the benefits of improved local control after the accelerated hyperfractionated radiation therapy. Conclusions: Accelerated hyperfractionation radiation therapy using 1.6 Gy per fraction/twice-a-day (b.i.d.) for a total dose of 70.4 Gy in 6 weeks is effective in achieving high local control of T3 squamous cell carcinoma of the oropharynx and larynx. The midcourse treatment gap should be as short as possible with the projected total dose and time. Should the gaps be unduly prolonged due to various circumstances, further increase in the total dose, for example, 72-75 Gy, and/or increase of the fraction sizes, for example, 1.8-2.0 Gy/f b.i.d. after the gap may be necessary to compensate for the adverse effects of the tumor regeneration from the prolonged gap

15th International Conference on Accelerator and Large Experimental Physics Control Systems

CERN Document Server

2015-01-01

ICALEPCS is a biennial series of conferences that is intended to: * Provide a forum for the interchange of ideas and information between control system specialists working on large experimental physics facilities around the world (accelerators, particle detectors, fusion reactors, telescopes, etc.); * Create an archival literature of developments and progress in this rapidly changing discipline; * Promote, where practical, standardization in both hardware and software; Promote collaboration between laboratories, institutes and industry.

First Steps Toward Incorporating Image Based Diagnostics Into Particle Accelerator Control Systems Using Convolutional Neural Networks

Energy Technology Data Exchange (ETDEWEB)

Edelen, A. L.; Biedron, S. G.; Milton, S. V.; Edelen, J. P.

2016-12-16

At present, a variety of image-based diagnostics are used in particle accelerator systems. Often times, these are viewed by a human operator who then makes appropriate adjustments to the machine. Given recent advances in using convolutional neural networks (CNNs) for image processing, it should be possible to use image diagnostics directly in control routines (NN-based or otherwise). This is especially appealing for non-intercepting diagnostics that could run continuously during beam operation. Here, we show results of a first step toward implementing such a controller: our trained CNN can predict multiple simulated downstream beam parameters at the Fermilab Accelerator Science and Technology (FAST) facility's low energy beamline using simulated virtual cathode laser images, gun phases, and solenoid strengths.

Control the length of beam trajectory with a quadruple triplet for heavy ion accelerator

International Nuclear Information System (INIS)

Zhang, Zhan; Wei, Shaoqing; Lee, Sang Jin; Kim, Do Gyun; Kim, Jang Youl

2016-01-01

Beam trajectory is needed to be controlled in heavy ion accelerator system. Quadruple magnets are widely used in heavy ion accelerator for focusing the transporting particles. A quadruple triplet system which consists of three consecutive quadrupoles, Q1, Q2 and Q3, is used to control beam trajectory at a focused position. Q1 and Q3 have symmetry with respect to Q2. The beam trajectory in magnet system is affected by higher order fields existed in real fields. For quadrupoles, the representation simulation of beam trajectory was carried out to study the beam trajectory and to estimate an effect of higher order field in triplet system. SCALA program was used to simulate the beam trajectory in OperaTM. SCALA can analyze a large number of beam trajectories at the same time by adjusting the size of finite element of the emitter. With OperaTM and MatlabTM programs, the position of focused beam spot in quadruple triplet system can be increased or decreased using evolution strategy (ES) method, therefore the length of triplet system can be controlled. Finally, the quadruple triplet system with the appropriate length and expected beam spot range was suggested in this paper

Control the length of beam trajectory with a quadruple triplet for heavy ion accelerator

Energy Technology Data Exchange (ETDEWEB)

Zhang, Zhan; Wei, Shaoqing; Lee, Sang Jin [Uiduk University, Gyeongju (Korea, Republic of); Kim, Do Gyun; Kim, Jang Youl [Rare Isotope Science Project, Institute for Basic Science, Daejeon (Korea, Republic of)

2016-12-15

Beam trajectory is needed to be controlled in heavy ion accelerator system. Quadruple magnets are widely used in heavy ion accelerator for focusing the transporting particles. A quadruple triplet system which consists of three consecutive quadrupoles, Q1, Q2 and Q3, is used to control beam trajectory at a focused position. Q1 and Q3 have symmetry with respect to Q2. The beam trajectory in magnet system is affected by higher order fields existed in real fields. For quadrupoles, the representation simulation of beam trajectory was carried out to study the beam trajectory and to estimate an effect of higher order field in triplet system. SCALA program was used to simulate the beam trajectory in OperaTM. SCALA can analyze a large number of beam trajectories at the same time by adjusting the size of finite element of the emitter. With OperaTM and MatlabTM programs, the position of focused beam spot in quadruple triplet system can be increased or decreased using evolution strategy (ES) method, therefore the length of triplet system can be controlled. Finally, the quadruple triplet system with the appropriate length and expected beam spot range was suggested in this paper.

Concept of control and modifying systems of accelerator components; Kontseptsiya sistem avtomatizatsii kontrolya i upravleniya

Energy Technology Data Exchange (ETDEWEB)

Gudkov, K A; Chepurnov, A S; Shumakov, A V [NNIYaF MGU, Moskva (Russian Federation)

1996-12-31

Paper considers the main trends of development of automated control and monitoring systems of accelerator components. Application of communication ring structures will enable to design highly efficient object-oriented systems of automation of research and process components. 5 refs.

Accelerated Reader[R]: What Are the Lasting Effects on the Reading Habits of Middle School Students Exposed to Accelerated Reader[R] in Elementary Grades?

Science.gov (United States)

Pavonetti, Linda M.; Brimmer, Kathryn M.; Cipielewski, James F.

Promoted by effective advertising and disseminated by word of mouth, many schools have adopted Accelerated Reader[R] as a supplementary reading program or as their primary reading program. Accelerated Reader[R]'s philosophy is that by using the system, students are motivated to read more and better books. A study investigated whether seventh grade…

Achieving Optimal Quantum Acceleration of Frequency Estimation Using Adaptive Coherent Control.

Science.gov (United States)

Naghiloo, M; Jordan, A N; Murch, K W

2017-11-03

Precision measurements of frequency are critical to accurate time keeping and are fundamentally limited by quantum measurement uncertainties. While for time-independent quantum Hamiltonians the uncertainty of any parameter scales at best as 1/T, where T is the duration of the experiment, recent theoretical works have predicted that explicitly time-dependent Hamiltonians can yield a 1/T^{2} scaling of the uncertainty for an oscillation frequency. This quantum acceleration in precision requires coherent control, which is generally adaptive. We experimentally realize this quantum improvement in frequency sensitivity with superconducting circuits, using a single transmon qubit. With optimal control pulses, the theoretically ideal frequency precision scaling is reached for times shorter than the decoherence time. This result demonstrates a fundamental quantum advantage for frequency estimation.

Accelerator Technology Division annual report, FY 1989

International Nuclear Information System (INIS)

1990-06-01

This paper discusses: accelerator physics and special projects; experiments and injectors; magnetic optics and beam diagnostics; accelerator design and engineering; radio-frequency technology; accelerator theory and simulation; free-electron laser technology; accelerator controls and automation; and high power microwave sources and effects

Beam control in the ETA-II linear induction accelerator

International Nuclear Information System (INIS)

Chen, Y.J.

1992-01-01

Corkscrew beam motion is caused by chromatic aberration and misalignment of a focusing system. We have taken some measures to control the corkscrew motion on the ETA-II induction accelerator. To minimize chromatic aberration, we have developed an energy compensation scheme which reduces energy sweep and differential phase advance within a beam pulse. To minimize the misalignment errors, we have developed a time-independent steering algorithm which minimizes the observed corkscrew amplitude averaged over the beam pulse. The steering algorithm can be used even if the monitor spacing is much greater than the system's cyclotron wavelength and the corkscrew motion caused by a given misaligned magnet is fully developed, i.e., the relative phase advance is greater than 2π. (Author) 5 figs., 11 refs

Simultaneous Multislice Echo Planar Imaging With Blipped Controlled Aliasing in Parallel Imaging Results in Higher Acceleration: A Promising Technique for Accelerated Diffusion Tensor Imaging of Skeletal Muscle.

Science.gov (United States)

Filli, Lukas; Piccirelli, Marco; Kenkel, David; Guggenberger, Roman; Andreisek, Gustav; Beck, Thomas; Runge, Val M; Boss, Andreas

2015-07-01

The aim of this study was to investigate the feasibility of accelerated diffusion tensor imaging (DTI) of skeletal muscle using echo planar imaging (EPI) applying simultaneous multislice excitation with a blipped controlled aliasing in parallel imaging results in higher acceleration unaliasing technique. After federal ethics board approval, the lower leg muscles of 8 healthy volunteers (mean [SD] age, 29.4 [2.9] years) were examined in a clinical 3-T magnetic resonance scanner using a 15-channel knee coil. The EPI was performed at a b value of 500 s/mm2 without slice acceleration (conventional DTI) as well as with 2-fold and 3-fold acceleration. Fractional anisotropy (FA) and mean diffusivity (MD) were measured in all 3 acquisitions. Fiber tracking performance was compared between the acquisitions regarding the number of tracks, average track length, and anatomical precision using multivariate analysis of variance and Mann-Whitney U tests. Acquisition time was 7:24 minutes for conventional DTI, 3:53 minutes for 2-fold acceleration, and 2:38 minutes for 3-fold acceleration. Overall FA and MD values ranged from 0.220 to 0.378 and 1.595 to 1.829 mm2/s, respectively. Two-fold acceleration yielded similar FA and MD values (P ≥ 0.901) and similar fiber tracking performance compared with conventional DTI. Three-fold acceleration resulted in comparable MD (P = 0.199) but higher FA values (P = 0.006) and significantly impaired fiber tracking in the soleus and tibialis anterior muscles (number of tracks, P DTI of skeletal muscle with similar image quality and quantification accuracy of diffusion parameters. This may increase the clinical applicability of muscle anisotropy measurements.

Report on the 2005 Particle Accelerator Conference (PAC05)

International Nuclear Information System (INIS)

Kathy F. Rosenbalm

2005-01-01

The 21st Particle Accelerator Conference, PAC05, took place at the Knoxville Convention Center (KCC) from Monday through Friday, May 16-20, 2005. Sponsored by the American Physical Society (APS), the Institute of Electrics and Electronics Engineers (IEEE) with its subdivision of Nuclear and Plasma Sciences Society (NPSS), the conference was hosted by the Oak Ridge National Laboratory (ORNL) Spallation Neutron Source (SNS) Project and Thomas Jefferson National Accelerator Facility (JLab). The conference was chaired by Norbert Holtkamp, and the Local Organizing Committee was made up of staff from the ORNL SNS Project under the chairmanship of Stuart Henderson. The conference welcomed over 1400 delegates from the United States, Europe, Asia, the Middle East, South America and from as far away as Australia. Almost 1400 papers where processed during the conference and will be published on the Joint Accelerator Conferences Website (JACoW) page

NOVEL TECHNIQUE OF POWER CONTROL IN MAGNETRON TRANSMITTERS FOR INTENSE ACCELERATORS

Energy Technology Data Exchange (ETDEWEB)

Kazakevich, G. [MUONS Inc., Batavia; Johnson, R. [MUONS Inc., Batavia; Neubauer, M.; Lebedev, V. [Fermilab; Schappert, W. [Fermilab; Yakovlev, V. [Fermilab

2016-10-21

A novel concept of a high-power magnetron transmitter allowing dynamic phase and power control at the frequency of locking signal is proposed. The transmitter compensating parasitic phase and amplitude modulations inherent in Superconducting RF (SRF) cavities within closed feedback loops is intended for powering of the intensity-frontier superconducting accelerators. The con- cept uses magnetrons driven by a sufficient resonant (in- jection-locking) signal and fed by the voltage which can be below the threshold of self-excitation. This provides an extended range of power control in a single magnetron at highest efficiency minimizing the cost of RF power unit and the operation cost. Proof-of-principle of the proposed concept demonstrated in pulsed and CW regimes with 2.45 GHz, 1kW magnetrons is discussed here. A conceptual scheme of the high-power transmitter allowing the dynamic wide-band phase and y power controls is presented and discussed.

KEK digital accelerator

Directory of Open Access Journals (Sweden)

T. Iwashita

2011-07-01

Full Text Available The High Energy Accelerator Research Organization KEK digital accelerator (KEK-DA is a renovation of the KEK 500 MeV booster proton synchrotron, which was shut down in 2006. The existing 40 MeV drift tube linac and rf cavities have been replaced by an electron cyclotron resonance (ECR ion source embedded in a 200 kV high-voltage terminal and induction acceleration cells, respectively. A DA is, in principle, capable of accelerating any species of ion in all possible charge states. The KEK-DA is characterized by specific accelerator components such as a permanent magnet X-band ECR ion source, a low-energy transport line, an electrostatic injection kicker, an extraction septum magnet operated in air, combined-function main magnets, and an induction acceleration system. The induction acceleration method, integrating modern pulse power technology and state-of-art digital control, is crucial for the rapid-cycle KEK-DA. The key issues of beam dynamics associated with low-energy injection of heavy ions are beam loss caused by electron capture and stripping as results of the interaction with residual gas molecules and the closed orbit distortion resulting from relatively high remanent fields in the bending magnets. Attractive applications of this accelerator in materials and biological sciences are discussed.

Radon and Lung Cancer Case-Control Study in Middle Ural

International Nuclear Information System (INIS)

Kirdin, I.A.; Lezhnin, V.L.; Yarmoshenko, I.V.; Ekidin, A.

2001-01-01

Full text: The pilot phase of radon and lung cancer case-control study has been performed in Karpinsk and Pervouralsk towns of Middle Ural region of Russia. The case group consists of 341 persons with lung cancer and living in that towns at least five previous years. The lung cancer diagnoses were carefully verified by instrumental techniques and 70% of its were morphologically validated. The persons for the control group (448) were chosen from the population living in that towns at least five years taking into account the age and sex. The special epidemiological questionnaire was developed which includes the items by the groups of factors as follow: clinical data, social factors, chronic lung diseases, life habit, tobacco smoking, alcohol drinking, diet preference etc. The epidemiological questionnaires were fulfilled for each member of case and control groups. Radon gas concentration and thoron equilibrium equivalent concentration measurements had been performed using nuclear track detectors and grab sampling accordingly in the dwellings of case and control groups members. By preliminary estimation the odds ratios are 1, 0.91, 1.2, 1.1 in the ranges of radon and thoron equilibrium equivalent concentration 0-6, 3-13, 13-36 and 36-370 Bq/m 3 respectively. The deeper and more rigorous analysis as well as different independent approaches will be discussed in the paper.(author)

Optically controlled laser-plasma electron accelerator for compact gamma-ray sources

Science.gov (United States)

Kalmykov, S. Y.; Davoine, X.; Ghebregziabher, I.; Shadwick, B. A.

2018-02-01

Generating quasi-monochromatic, femtosecond γ-ray pulses via Thomson scattering (TS) demands exceptional electron beam (e-beam) quality, such as percent-scale energy spread and five-dimensional brightness over 1016 A m-2. We show that near-GeV e-beams with these metrics can be accelerated in a cavity of electron density, driven with an incoherent stack of Joule-scale laser pulses through a mm-size, dense plasma (n 0 ˜ 1019 cm-3). Changing the time delay, frequency difference, and energy ratio of the stack components controls the e-beam phase space on the femtosecond scale, while the modest energy of the optical driver helps afford kHz-scale repetition rate at manageable average power. Blue-shifting one stack component by a considerable fraction of the carrier frequency makes the stack immune to self-compression. This, in turn, minimizes uncontrolled variation in the cavity shape, suppressing continuous injection of ambient plasma electrons, preserving a single, ultra-bright electron bunch. In addition, weak focusing of the trailing component of the stack induces periodic injection, generating, in a single shot, a train of bunches with controllable energy spacing and femtosecond synchronization. These designer e-beams, inaccessible to conventional acceleration methods, generate, via TS, gigawatt γ-ray pulses (or multi-color pulse trains) with the mean energy in the range of interest for nuclear photonics (4-16 MeV), containing over 106 photons within a microsteradian-scale observation cone.

Gastrointestinal mean transit times in young and middle-aged healthy subjects

DEFF Research Database (Denmark)

Graff, J; Brinch, K; Madsen, Jan Lysgård

2001-01-01

To investigate the effects of age and gender on gastric, small intestinal and colonic mean transit times, a study was conducted in 32 healthy volunteers: eight young women (22-30 years), eight young men (20-28 years), eight middle-aged women (43-51 years) and eight middle-aged men (38-53 years......, small intestinal and colonic mean transit times were calculated. The gastric, small intestinal and colonic mean transit times were significantly longer in women. Ageing was shown to accelerate the gastric and small intestinal transit significantly. In the group of men the colonic mean transit time...... was unaffected by age, but middle-aged women had a significantly slower colonic transit than young women. We therefore conclude that both age and gender have to be considered when reference values for gastric, small intestinal and colonic mean transit times have to be established....

Flood risk control of dams and dykes in middle reach of Huaihe River

Directory of Open Access Journals (Sweden)

Zhen-kun MA

2014-01-01

Full Text Available Three stochastic mathematical models for calculation of the reservoir flood regulation process, river course flood release, and flood risk rate under flood control were established based on the theory of stochastic differential equations and features of flood control systems in the middle reach of the Huaihe River from Xixian to the Bengbu floodgate, comprehensively considering uncertain factors of hydrology, hydraulics, and engineering control. They were used to calculate the flood risk rate with flood regulation of five key reservoirs, including the Meishan, Xianghongdian, Nianyushan, Mozitan, and Foziling reservoirs in the middle reach of the Huaihe River under different flood frequencies, the flood risk rate with river course flood release under design and check floods for the trunk of the Huaihe River in conjunction with relevant flood storage areas, and the flood risk rate with operation of the Linhuaigang Project under design and check floods. The calculated results show that (1 the five reservoirs can withstand design floods, but the Xianghongdian and Foziling reservoirs will suffer overtopping accidents under check floods; (2 considering the service of flood storage areas under the design flood conditions of the Huaihe River, the mean flood risk rate with flood regulation of dykes and dams from Xixian to the Bengbu floodgate is about 0.2, and the trunk of the Huaihe River can generally withstand design floods; and (3 under a check flood with the flood return period of 1 000 years, the risk rate of overtopping accidents of the Linhuaigang Project is not larger than 0.15, indicating that it has a high flood regulation capacity. Through regulation and application of the flood control system of the Linhuigang Project, the Huaihe River Basin can withstand large floods, and the safety of the protected area can be ensured.

Acceleration feedback of a current-following synchronized control algorithm for telescope elevation axis

Science.gov (United States)

Tang, Tao; Zhang, Tong; Du, Jun-Feng; Ren, Ge; Tian, Jing

2016-11-01

This paper proposes a dual-motor configuration to enhance closed-loop performance of a telescope control system. Two identical motors are mounted on each side of a U-type frame to drive the telescope elevation axis instead of a single motor drive, which is usually used in a classical design. This new configuration and mechanism can reduce the motor to half the size used in the former design, and it also provides some other advantages. A master-slave current control mode is employed to synchronize the two motors. Acceleration feedback control is utilized to further enhance the servo performance. Extensive experiments are used to validate the effectiveness of the proposed control algorithm in synchronization, disturbance attenuation and low-velocity tracking.

Accelerator-driven subcritical systems - An analysis with a focus on non-proliferation and export control

International Nuclear Information System (INIS)

Andersson, Per; Nielsen, Fredrik; Sunhede, Daniel

2013-01-01

The Department of Nuclear Weapons Related Issues at The Swedish Defence Research Agency, FOI, as commissioned by the Swedish Radiation Safety Authority, SSM, conducted a study concerning Accelerator Driven Subcritical Systems, ADS, with emphasis on non-proliferation and export control. An ADS looks at first glance like a traditional nuclear reactor, but the nuclear core is designed to always remain subcritical, both during normal and off-normal conditions. Neutrons are instead supplied by an external source in the form of an proton accelerator and a spallation target. This report gives a short walk-through to the physical processes that governs the neutron flux and reactivity in the core and how they are affected by the design of the core including the accelerator and spallation target. Furthermore is the results from reactor core simulations presented, where the isotopic nuclear fuel inventory has been studied as a function of burn up and initial configuration. Finally the report contains an analysis of the potential risks involved from the perspective of nuclear proliferation and exports. This study shows that ADS in the future could constitute a proliferation concern. The subsystems and components in question share design and materials with the equivalent components in traditional reactors with the exception of the proton accelerator and spallation target, which is unique for accelerator driven systems

Using Patterns for Multivariate Monitoring and Feedback Control of Linear Accelerator Performance: Proof-of-Concept Research

International Nuclear Information System (INIS)

Cordes, Gail Adele; Van Ausdeln, Leo Anthony; Velasquez, Maria Elena

2002-01-01

The report discusses preliminary proof-of-concept research for using the Advanced Data Validation and Verification System (ADVVS), a new INEEL software package, to add validation and verification and multivariate feedback control to the operation of non-destructive analysis (NDA) equipment. The software is based on human cognition, the recognition of patterns and changes in patterns in time-related data. The first project applied ADVVS to monitor operations of a selectable energy linear electron accelerator, and showed how the software recognizes in real time any deviations from the optimal tune of the machine. The second project extended the software method to provide model-based multivariate feedback control for the same linear electron accelerator. The projects successfully demonstrated proof-of-concept for the applications and focused attention on the common application of intelligent information processing techniques

Dusty-Plasma Particle Accelerator

Science.gov (United States)

Foster, John E.

2005-01-01

initiation of a low-current, high-voltage cathode spot. Plasma pressure associated with the cathode spot as well as the large voltage drop at the cathode spot accelerates the charged particles toward the substrate. The ultimate kinetic energy attained by particles exiting the particle holder depends in part on the magnitude of the cathode spot sheath potential difference, which is proportional to the magnitude of the voltage pulse, and the on the electric charge on the dust. The magnitude of the voltage pulse can be controlled directly, whereas the particle s electric charge can be controlled indirectly by controlling the operating parameters of the plasma apparatus.

Real-time Optical Network for Accelerator Control

Energy Technology Data Exchange (ETDEWEB)

Lee, Keun

2012-06-27

The timing requirements of a modern accelerator complex call for several features. The first is a system for high precision relative timing among accelerator components. Stabilized fiber links have already been demonstrated to achieve sub-10 femtoseconds relative timing precision. The second is a system for timing distribution of absolute time with sufficient precision to identify a specific RF bucket. The White Rabbit technology is a promising candidate to deliver the absolute time that is linked to the GPS clock. In this study we demonstrated that these two technologies can be combined in a way that the absolute time information can be delivered to the stabilized fiber link system. This was accomplished by researching the design of the stabilized fiber and White Rabbit systems and devising adaptation modules that facilitate co-existence of both systems in the same FPGA environment. We built a prototype system using off-the-shelf products and implemented a proof-of-concept version of the FPGA firmware. The test verified that the White Rabbit features operate correctly under the stabilized fiber system environment. This work demonstrates that turn-key femtosecond timing systems with absolute time information can be built cost effectively and deployed in various accelerator environments. This will lead to many new applications in chemistry, biology and surface dynamics, to name a few.

Ionization front accelerator

International Nuclear Information System (INIS)

Olson, C.L.

1975-01-01

In a recently proposed linear collective accelerator, ions are accelerated in a steep, moving potential well created at the head of an intense relativistic electron beam. The steepness of the potential well and its motion are controlled by the external ionization of a suitable background gas. Calculations concerning optimum choices for the background gas and the ionization method are presented; a two-step photoionization process employing Cs vapor is proposed. In this process, a super-radiant light source is used to excite the gas, and a UV laser is used to photoionize the excited state. The appropriate line widths and coupled ionization growth rate equations are discussed. Parameter estimates are given for a feasibility experiment, for a 1 GeV proton accelerator, and for a heavy ion accelerator (50 MeV/nucleon uranium). (auth)

Learning Leadership Skills in Middle School

Science.gov (United States)

Bowman, Richard F.

2013-01-01

For middle school students, the essence of 21st-century leadership development is being "in influence" versus being "in control." A core student leadership skill involves listening intently to others, framing others' concerns, and advancing the other person's interests. Creating contexts in which middle school…

An improved phase-control system for superconducting low-velocity accelerating structures

International Nuclear Information System (INIS)

Bogaty, J.M.; Clifft, B.E.; Shepard, K.W.; Zinkann, G.P.

1989-01-01

Microphonic fluctuations in the rf eigenfrequency of superconducting (SC) slow-wave structures must be compensated by a fast-tuning system in order to control the rf phase. The tuning system must handle a reactive power proportional to the product of the tuning range and the rf energy content of the resonant cavity. The accelerating field level of many of the SC cavities forming the ATLAS linac has been limited by the rf power capacity of the presently used PIN-diode based fast-tuner. A new system has been developed, utilizing PIN diodes operating immersed in liquid nitrogen, with the diodes controlled by a high-voltage VMOS FET driver. The system has operated at reactive power levels above 20 KVA, a factor of four increase over an earlier design. 7 refs., 2 figs

An improved phase-controlled system for superconducting low-velocity accelerating structures

International Nuclear Information System (INIS)

Bogaty, J.M.; Clifft, B.E.; Shepard, K.W.; Zinkann, G.P.

1989-01-01

Microphonic fluctuations in the RF eigenfrequency of supeconducting (SC) slow-wave structures must be compensated by a fast-tuning system in order to control the RF phase. The tuning system must handle a reactive power proportional to the product of the tuning range and the RF energy content of the resonant cavity. The accelerating field level of many of the SC cavities forming the ATLAS linac has been limited by the RF power capacity of the presently used PIN-diode based fast-tuner. A new system has been developed, utilizing PIN diodes operating immersed in liquid nitrogen, with the diodes controlled by a high-voltage VMOS FET driver. The system has operated at reactive power levels above 20 KVA, a factor of four increase over an earlier design. 7 refs., 2 figs

An improved phase-control system for superconducting low-velocity accelerating structures

Energy Technology Data Exchange (ETDEWEB)

Bogaty, J.M.; Clifft, B.E.; Shepard, K.W.; Zinkann, G.P.

1989-01-01

Microphonic fluctuations in the rf eigenfrequency of superconducting (SC) slow-wave structures must be compensated by a fast-tuning system in order to control the rf phase. The tuning system must handle a reactive power proportional to the product of the tuning range and the rf energy content of the resonant cavity. The accelerating field level of many of the SC cavities forming the ATLAS linac has been limited by the rf power capacity of the presently used PIN-diode based fast-tuner. A new system has been developed, utilizing PIN diodes operating immersed in liquid nitrogen, with the diodes controlled by a high-voltage VMOS FET driver. The system has operated at reactive power levels above 20 KVA, a factor of four increase over an earlier design. 7 refs., 2 figs.

Virtual accelerator concept, implementation and preliminary test

International Nuclear Information System (INIS)

Uriot, D.; Duperrier, R.

2006-05-01

A virtual accelerator is the coupling of a simulation code with the control system of a real machine. 3 operating modes are considered. First, the monitoring mode in which any action on the control system has an impact on both real and virtual machines. This mode allows a direct comparison between simulation results and the real behaviour of the accelerator. Secondly, the flight simulation mode, this mode allows the accelerator operators to simulate the effect of any change in the parameters of the control system before transferring them to the real machine. The main advantage of this mode is to allow the assessment of operating procedures before implementing them on the real machine. The third mode is the automatic steering mode in which the simulation code assumes the reins of the control system of the real machine. This mode allows the making of complex and time-consuming adjustment procedures in an automatic way. TraceWin is a simulation code dedicated to the behaviour of charged-particle beams in a linear accelerator. TraceWin is consistent with the EPICS technology on which the control system of most accelerators is based. A virtual accelerator composed of the SILHI injector combined to the TraceWin code via the EPICS environment has showed its efficiency in the automatic steering mode. (A.C.)

Relativistically Induced Transparency Acceleration (RITA) - laser-plasma accelerated quasi-monoenergetic GeV ion-beams with existing lasers?

Science.gov (United States)

Sahai, Aakash A.

2013-10-01

Laser-plasma ion accelerators have the potential to produce beams with unprecedented characteristics of ultra-short bunch lengths (100s of fs) and high bunch-charge (1010 particles) over acceleration length of about 100 microns. However, creating and controlling mono-energetic bunches while accelerating to high-energies has been a challenge. If high-energy mono-energetic beams can be demonstrated with minimal post-processing, laser (ω0)-plasma (ωpe) ion accelerators may be used in a wide-range of applications such as cancer hadron-therapy, medical isotope production, neutron generation, radiography and high-energy density science. Here we demonstrate using analysis and simulations that using relativistic intensity laser-pulses and heavy-ion (Mi ×me) targets doped with a proton (or light-ion) species (mp ×me) of trace density (at least an order of magnitude below the cold critical density) we can scale up the energy of quasi-mono-energetically accelerated proton (or light-ion) beams while controlling their energy, charge and energy spectrum. This is achieved by controlling the laser propagation into an overdense (ω0 RITA). Desired proton or light-ion energies can be achieved by controlling the velocity of the snowplow, which is shown to scale inversely with the rise-time of the laser (higher energies for shorter pulses) and directly with the scale-length of the plasma density gradient. Similar acceleration can be produced by controlling the increase of the laser frequency (Chirp Induced Transparency Acceleration, ChITA). Work supported by the National Science Foundation under NSF- PHY-0936278. Also, NSF-PHY-0936266 and NSF-PHY-0903039; the US Department of Energy under DEFC02-07ER41500, DE- FG02-92ER40727 and DE-FG52-09NA29552.

Externally Controlled Injection of Electrons by a Laser Pulse in a Laser Wakefield Electron Accelerator

CERN Document Server

Chen Szu Yuan; Chen Wei Ting; Chien, Ting-Yei; Lee, Chau-Hwang; Lin, Jiunn-Yuan; Wang, Jyhpyng

2005-01-01

Spatially and temporally localized injection of electrons is a key element for development of plasma-wave electron accelerator. Here we report the demonstration of two different schemes for electron injection in a self-modulated laser wakefield accelerator (SM-LWFA) by using a laser pulse. In the first scheme, by implementing a copropagating laser prepulse with proper timing, we are able to control the growth of Raman forward scattering and the production of accelerated electrons. We found that the stimulated Raman backward scattering of the prepulse plays the essential role of injecting hot electrons into the fast plasma wave driven by the pump pulse. In the second scheme, by using a transient density ramp we achieve self-injection of electrons in a SM-LWFA with spatial localization. The transient density ramp is produced by a prepulse propagating transversely to drill a density depression channel via ionization and expansion. The same mechanism of injection with comparable efficiency is also demonstrated wi...

TIARA electrostatic accelerator facility

International Nuclear Information System (INIS)

Tajima, Satoshi; Takada, Isao; Mizuhashi, Kiyoshi; Uno, Sadanori; Ohkoshi, Kiyonori; Nakajima, Yoshinori; Saitoh, Yuichi; Ishii, Yasuyuki; Kamiya, Tomihiro

1996-07-01

In order to promote the Advanced Radiation Technology Project, Japan Atomic Energy Research Institute constructed TIARA facility composed of four ion accelerators at Takasaki Radiation Chemistry Research Establishment for the period from 1988 to 1993. A 3MV tandem accelerator and an AVF cycrotron were completed in 1991 as the first phase of the construction, and a 3MV single-ended accelerator and a 400kV ion implanter were completed in 1993 as the second phase. Three electrostatic accelerators, the tandem, the single-ended and the implanter, were installed in the Multiple-beam facility of TIARA and have been operated for various experiments with using single, dual and triple beams without any serious trouble. This report describes the constructive works, machine performances, control systems, safety systems and accessory equipments of the electrostatic accelerators. (author)

Optically controlled seeding of Raman forward scattering and injection of electrons in a self-modulated laser-wakefield accelerator

International Nuclear Information System (INIS)

Chen, W.-T.; Chien, T.-Y.; Lee, C.-H.; Lin, J.-Y.; Wang, J.; Chen, S.-Y.

2004-01-01

Optical seeding of plasma waves and the injection of electrons are key issues in self-modulated laser-wakefield accelerators. By implementing a copropagating laser prepulse with proper timing, we are able to control the growth of Raman forward scattering and the production of accelerated electrons. The dependence of the Raman intensity on prepulse timing indicates that the seeding of Raman forward scattering is dominated by the ionization-induced wakefield, and the dependence of the divergence and number of accelerated electrons further reveals that the stimulated Raman backward scattering of the prepulse plays the essential role of injecting hot electrons into the fast plasma wave driven by the main pulse

A low cost modular control and instrumentation system for accelerators

International Nuclear Information System (INIS)

Shubaly, M.R.; Plato, J.G.; Davis, R.W.

1984-01-01

A modular control and instrumentation system, being developed for the RFQ1 accelerator and for ion beam test facilities, is based on an intelligent crate and interchangeable plug-in modules for specific applications. The 8085-based microcomputer used in the system can access up to 256 K of memory, has up to 64 levels of vectored interrupts and time of day, and supports terminals, printers, floppy discs and digital cassette drives. This computer is linked to a bus in the front of the crate which carries not only the usual address, data, and control signals, but also interrupt lines and interrupt chip control lines. This bus is designed for easy interfacing. Plug-in modules connect to the bus, and to monitored equipment via a separate connector leading to a terminal strip on the rear of the crate. These modules monitor absolute and differential temperature, flow-rate, voltages and currents and switch settings. A permanently installed module provides ac power switching, an RS232 serial link and full duplex fibre optic serial links for connection to a central computer. Software for the crate provides for task scheduling, data storage and limit tests, communication to higher levels of the control system and field configuration of the crate. (orig.)

Workshop on Accelerator Operation (WAO 2001)

International Nuclear Information System (INIS)

Bailey, R.

2001-01-01

The 3rd Workshop on Accelerator Operation (WAO 2001) followed earlier workshops in 1996 and 1998. Most topics relevant for the efficient and effective operation of accelerators were covered. These included the tools and utilities necessary in the control rooms; the organization of accelerator operation (process monitoring, shift work, stress); the monitoring of beam quality; safety issues and standards; and questions particularly relevant for superconducting accelerators, in particular cryogenics. (author)

Accelerated intermittent Theta Burst stimulation for suicide risk in therapy-resistant depressed patients: a randomized, sham-controlled trial.

Directory of Open Access Journals (Sweden)

Stefanie Desmyter

2016-09-01

Full Text Available Objectives We aimed to examine the effects and safety of accelerated intermittent Theta Burst Stimulation (iTBS on suicide risk in a group of treatment-resistant unipolar depressed patients, using an extensive suicide assessment scale. Methods In 50 therapy-resistant, antidepressant-free depressed patients, an intensive protocol of accelerated iTBS was applied over the left dorsolateral prefrontal cortex in a randomized, sham-controlled cross-over design. Patients received 20 iTBS sessions over 4 days. Suicide risk was assessed using the Beck Scale of Suicide ideation (BSI. Results The iTBS protocol was safe and well-tolerated. We observed a significant decrease of the BSI score over time, unrelated to active or sham stimulation and unrelated to depression-response. No worsening of suicidal ideation was observed. The effects of accelerated iTBS on mood and depression severity are reported in Duprat et al. (2016. The decrease in suicide risk lasted up to one month after baseline, even in depression non-responders. Conclusions This accelerated iTBS protocol was safe. The observed significant decrease in suicide risk was unrelated to active or sham stimulation and unrelated to depression response. Further sham-controlled research in suicidal depressed patients is necessary.(clinicaltrials.gov identifier: NCT01832805

Accelerated Intermittent Theta Burst Stimulation for Suicide Risk in Therapy-Resistant Depressed Patients: A Randomized, Sham-Controlled Trial.

Science.gov (United States)

Desmyter, Stefanie; Duprat, Romain; Baeken, Chris; Van Autreve, Sara; Audenaert, Kurt; van Heeringen, Kees

2016-01-01

Objectives: We aimed to examine the effects and safety of accelerated intermittent Theta Burst Stimulation (iTBS) on suicide risk in a group of treatment-resistant unipolar depressed patients, using an extensive suicide assessment scale. Methods: In 50 therapy-resistant, antidepressant-free depressed patients, an intensive protocol of accelerated iTBS was applied over the left dorsolateral prefrontal cortex (DLPFC) in a randomized, sham-controlled crossover design. Patients received 20 iTBS sessions over 4 days. Suicide risk was assessed using the Beck Scale of Suicide ideation (BSI). Results: The iTBS protocol was safe and well tolerated. We observed a significant decrease of the BSI score over time, unrelated to active or sham stimulation and unrelated to depression-response. No worsening of suicidal ideation was observed. The effects of accelerated iTBS on mood and depression severity are reported in Duprat et al. (2016). The decrease in suicide risk lasted up to 1 month after baseline, even in depression non-responders. Conclusions: This accelerated iTBS protocol was safe. The observed significant decrease in suicide risk was unrelated to active or sham stimulation and unrelated to depression response. Further sham-controlled research in suicidal depressed patients is necessary. (Clinicaltrials.gov identifier: NCT01832805).

Middle-to-Upper Palaeolithic site formation processes at the Bordes-Fitte rockshelter (Central France)

DEFF Research Database (Denmark)

Aubry, Thierry; Dimuccio, Luca Antonio; Buylaert, Jan-Pieter

2014-01-01

. In this article we use the Middle and Early Upper Palaeolithic archaeo-stratigraphic record from the Bordes-Fitte rockshelter (les Roches d'Abilly site, Central France), a Bayesian analysis of the ages obtained by accelerator mass spectrometry radiocarbon on ultrafiltered collagen and by luminescence on quartz...

Micro-computer based control system and its software for carrying out the sequential acceleration on SMCAMS

International Nuclear Information System (INIS)

Li Deming

2001-01-01

Micro-computer based control system and its software for carrying out the sequential acceleration on SMCAMS is described. Also, the establishment of the 14 C particle measuring device and the improvement of the original power supply system are described

Recent progress in particle accelerators

International Nuclear Information System (INIS)

Cole, F.T.; Mills, F.E.

1988-01-01

Many accelerators have also been built for medical radiography and therapy. Electron accelerators for this application are available commercially, using the electrons directly or bremsstrahlung photons. Neutrons produced by accelerator beams have also been used for therapy with considerable success, and several proton accelerators built for physics research have been adapted for direct therapy with protons. The first proton accelerator specifically for therapy is now being built. Separate from what might be called conventional accelerator technology, an entirely new field utilizing very highly pulsed power has been developed, and beams of short pulses of thousands or millions of amperes peak current in the MeV energy range are now available. These beams have important applications in high-energy particle acceleration, controlled fusion, industrial treatment of materials, and possibly in food preservation. All of these accelerators make use of external fields of acceleration. There is also vigorous research into new methods of acceleration, in many schemes making use of the intense accelerating fields, generated by laser beams or by plasma states of matter. This research has not as yet made traditional kinds of accelerators outmoded, but many workers hope that early in the next century there will be practical new acceleration methods making use of these very high fields. These developments are discussed in detail

The Nuclear Question. After Iran: Toward Nuclear Proliferation in the Middle East?

International Nuclear Information System (INIS)

Courmont, Barthelemy

2008-01-01

Iran's potential acquirement of the atomic bomb could lead to nuclear proliferation in the Middle East. Many countries in the region would be tempted to follow the Iranian example, in order to maintain their regional power. This development could produce significant geopolitical consequences in a region where relationships are already tense. In this context, one can envisage different crisis scenarios: support for terrorist acts, attacks on American bases in the region, threats against the state of Israel. Accelerated nuclear proliferation in the Middle East would also jeopardize the efforts undertaken by regional actors during the past four decades to create a Nuclear Weapon Free Zone (NWFZ)

CNSTN Accelerator

International Nuclear Information System (INIS)

Habbassi, Afifa; Trabelsi, Adel

2010-01-01

This project give a big idea about the measurement of the linear accelerator in the CNSTN. During this work we control dose distribution for different product. For this characterisation we have to make an installation qualification ,operational qualification,performance qualification and of course for every step we have to control temperature and the dose ,even the distribution of the last one.

Modular system for the control of complex accelerators using portable software

International Nuclear Information System (INIS)

von der Schmitt, H.; Aufhaus, H.

1982-01-01

When designing the Mainz Microtron control system, care was taken to achieve an expandable system with long-lived application software. A multi-processor system was built from the beginning. The software is split into modules, according to function and position in hierarchy, which are distributed over the computers. The decoupling which results from modularity eases software development and maintainance. RATFOR was chosen as implementation language. With a message system for communication between the modules, several aims were reached at once: (1) symbolic addressing of the accelerator components throughout the software layers, (2) transparent access to I/O devices (CAMAC) at remote computers, (3) multitasking in FORTRAN (and RATFOR) programs, (4) a separating layer for adaptation to different operating systems - essential points for software portability. The system is in operation since April 1979 for the control of MAMI stage I

Acceleration Modes and Transitions in Pulsed Plasma Accelerators

Science.gov (United States)

Polzin, Kurt A.; Greve, Christine M.

2018-01-01

accelerators was developed by Cheng, et al. The Coaxial High ENerGy (CHENG) thruster operated on the 10-microseconds timescales of pulsed plasma thrusters, but claimed high thrust density, high efficiency and low electrode erosion rates, which are more consistent with the deflagration mode of acceleration. Separate work on gas-fed pulsed plasma thrusters (PPTs) by Ziemer, et al. identified two separate regimes of performance. The regime at higher mass bits (termed Mode I in that work) possessed relatively constant thrust efficiency (ratio of jet kinetic energy to input electrical energy) as a function of mass bit. In the second regime at very low mass bits (termed Mode II), the efficiency increased with decreasing mass bit. Work by Poehlmann et al. and by Sitaraman and Raja sought to understand the performance of the CHENG thruster and the Mode I / Mode II performance in PPTs by modeling the acceleration using the Hugoniot Relation, with the detonation and deflagration modes representing two distinct sets of solutions to the relevant conservation laws. These works studied the proposal that, depending upon the values of the various controllable parameters, the accelerator would operate in either the detonation or deflagration mode. In the present work, we propose a variation on the explanation for the differences in performance between the various pulsed plasma accelerators. Instead of treating the accelerator as if it were only operating in one mode or the other during a pulse, we model the initial stage of the discharge in all cases as an accelerating current sheet (detonation mode). If the current sheet reaches the exit of the accelerator before the discharge is completed, the acceleration mode transitions to the deflagration mode type found in the quasi-steady MPD thrusters. This modeling method is used to demonstrate that standard gas-fed pulsed plasma accelerators, the CHENG thruster, and the quasi-steady MPD accelerator are variations of the same device, with the overall

Development of a new concept automatic frequency controller for an ultrasmall C-band linear accelerator guide

International Nuclear Information System (INIS)

Kamino, Yuichiro; Tsukuda, Kazuhiro; Kokubo, Masaki; Miura, Sadao; Hirai, Etsuro; Hiraoka, Masahiro; Ishikawa, Junzo

2007-01-01

We are developing a four-dimensional, image-guided radiotherapy system with a gimbaled x-ray head. The system has pursuing irradiation capability in addition to precise irradiation capability, owing to its agile x-ray head. The moving x-ray head requires a very small C-band accelerator guide. The heat intensity of the accelerator guide is much higher than that of conventional S-band medical linear accelerators. The resonance frequency varies over almost 1.0 MHz with a thermal time constant of about 30 s. An automatic frequency controller (AFC) is employed to compensate for this variation in resonance frequency. Furthermore, we noted that fast AFC response is important for step-and-shoot intensity modulation radiotherapy (IMRT), in which the beam is turned on and off frequently. Therefore, we invented a digital AFC, based on a new concept, to provide effective compensation for the thermal characteristics of the accelerator guide and to ensure stable and optimized x-ray treatment. An important aspect of the performance of the AFC is the capture-frequency range over which the AFC can seek, lock on to, and track the resonance frequency. The conventional, analog AFC used in S-band medical linear accelerators would have a capture-frequency range of about 0.9 MHz, if applied to our accelerator guide, and would be inappropriate. Conversely, our new AFC has a capture-frequency range of 24 MHz, which is well suited to our accelerator guide. The design concept behind this new AFC has been developed and verified. A full prototype system was constructed and tested on an existing accelerator guide at the rated x-ray output (500 cGy/min) of our radiotherapy system, with a pulse-repetition frequency of 300 Hz. The AFC acquired the resonance frequency of the accelerator guide within 0.15 s after beam-on, and provided stable tracking and adjustment of the frequency of the microwave source to the resonance frequency of the accelerator guide. With a planned improvement of the

Training for improved neuro-muscular control of balance in middle aged females.

Science.gov (United States)

Anderson, Gregory S; Deluigi, Fabio; Belli, Guido; Tentoni, Claudio; Gaetz, Michael B

2016-01-01

This study examined improvements in static balance and muscle electromyographic (EMG) activity following a four week progressive training program in 16 middle aged females (mean age = 46.9 ± 8.7 yrs; height 161.1 ± 6.0 cm; weight 65.4 ± 11.2 kg). Participants trained 3 times per week for 4 weeks, for 50 min per session, progressing base of support, stability, vision, resistance and torque in each of six basic exercises. Pre and post training measures of balance included feet together standing, a tandem stance and a one-leg stand (unsupported leg in the saggital plane) performed with the eyes closed, and a Stork Stand (unsupported leg in the frontal plane) with both eyes open and closed. In each position postural deviations were tallied for each individual while muscle recruitment was determined using root mean squared (RMS) EMG activity for the soleus, biceps femoris, erector spinae, rectus abdominis and internal oblique muscles of the dominant foot side. Balance scores were significantly improved post training in both the Balance Error Score System (p training in all muscles in each condition except the soleus in the tandem position, although not all significantly. Reduced biceps femoris activity suggest that improved core stability allowed participants to move from a hip to an ankle postural control strategy through improved coordination of muscles involved in balance and reduced body sway. The core muscles were able to control body position with less activity post training suggesting improved muscle coordination and efficiency. These results suggest that short term progressive floor to BOSU™ balance training can improve standing balance in middle aged women. Copyright © 2015 Elsevier Ltd. All rights reserved.

Middle East physics collaboration plans for the future

CERN Multimedia

CERN Bulletin

2011-01-01

The SESAME initiative, the Synchrotron-light for Experimental Science and Applications in the Middle East, is making progress. At a recent SESAME Council meeting at the end of May, Jordan, Iran and Israel confirmed their cash contributions to the project’s storage ring. The Palestinian Authority and Pakistan have confirmed their in-kind support and Egypt and Turkey are taking steps to allow their participation. Technically planned to start operation in 2015, SESAME has begun to show significant potential as a science for peace initiative in the Middle East.   The SESAME site in Allaan, Jordan.                   (© SESAME) Jordan has provided the land and an elegant building that will house the accelerator complex and associated infrastructure; a number of states, organizations and synchrotron light laboratories have donated the injector and booster, beam lines or components, support for infras...

Accelerators course

CERN Multimedia

CERN. Geneva HR-RFA; Métral, E

2006-01-01

1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges

Accelerated Electron-Beam Formation with a High Capture Coefficient in a Parallel Coupled Accelerating Structure

Science.gov (United States)

Chernousov, Yu. D.; Shebolaev, I. V.; Ikryanov, I. M.

2018-01-01

An electron beam with a high (close to 100%) coefficient of electron capture into the regime of acceleration has been obtained in a linear electron accelerator based on a parallel coupled slow-wave structure, electron gun with microwave-controlled injection current, and permanent-magnet beam-focusing system. The high capture coefficient was due to the properties of the accelerating structure, beam-focusing system, and electron-injection system. Main characteristics of the proposed systems are presented.

Accelerated cyclic corrosion tests

Directory of Open Access Journals (Sweden)

Prošek T.

2016-06-01

Full Text Available Accelerated corrosion testing is indispensable for material selection, quality control and both initial and residual life time prediction for bare and painted metallic, polymeric, adhesive and other materials in atmospheric exposure conditions. The best known Neutral Salt Spray (NSS test provides unrealistic conditions and poor correlation to exposures in atmosphere. Modern cyclic accelerated corrosion tests include intermittent salt spray, wet and dry phases and eventually other technical phases. They are able to predict the material performance in service more correctly as documented on several examples. The use of NSS should thus be restricted for quality control.

The Quality Control of Intensity Modulated Radiation Therapy (IMRT for ONCOR Siemens Linear Accelerators Using Film Dosimetry

Directory of Open Access Journals (Sweden)

Keyvan Jabbari

2012-03-01

Full Text Available Introduction Intensity Modulated Radiation Therapy (IMRT has made a significant progress in radiation therapy centers in recent years. In this method, each radiation beam is divided into many subfields that create a field with a modulated intensity. Considering the complexity of this method, the quality control for IMRT is a topic of interest for researchers. This article is about the various steps of planning and quality control of Siemens linear accelerators for IMRT, using film dosimetry. This article in addition to review of the techniques, discusses the details of experiments and possible sources of errors which are not mentioned in the protocols and other references. Materials and Methods This project was carried out in Isfahan Milad hospital which has two Siemens ONCOR linear accelerators. Both accelerators are equipped with Multi-Leaf Collimators (MLC which enables us to perform IMRT delivery in the step-and-shoot method. The quality control consists of various experiments related to the sections of radiation therapy. In these experiments, the accuracy of some components such as treatment planning system, imaging device (CT, MLC, control system of accelerator, and stability of the output are evaluated. The dose verification is performed using film dosimetry method. The films were KODAK-EDR2, which were calibrated before the experiments. One of the important steps is the comparison of the calculated dose with planning system and the measured dose in experiments. Results The results of the experiments in various steps have been acceptable according to the standard protocols. The calibration of MLC and evaluation of the leakage through the leaves of MLC was performed by using the film dosimetry and visual check. In comparison with calculated and measured dose, more that 80% of the points have to be in agreement within 3% of the value. In our experiments, between 85 and 90% of the points had such an agreement with IMRT delivery. Conclusion

Effect of controlled exercise on middle gluteal muscle fibre composition in Thoroughbred foals.

Science.gov (United States)

Eto, D; Yamano, S; Kasashima, Y; Sugiura, T; Nasu, T; Tokuriki, M; Miyata, H

2003-11-01

Most racehorses are trained regularly from about age 18 months; therefore, little information is available on the effect of training in Thoroughbred foals. Well-controlled exercise could improve muscle potential ability for endurance running. Thoroughbred foals at age 2 months were separated into control and training (treadmill exercise) groups and samples obtained from the middle gluteal muscle at 2 and 12 months post partum. Muscle fibre compositions were determined by histochemical and electrophoretical techniques and succinic dehydrogenase (SDH) activity was analysed in each fibre type. All fibre types were hypertrophied with growth and type I and IIA fibres were significantly larger in the training than the control group at age 12 months. A significant increase of SDH activity was found in type IIX muscle fibres in the training group. Training in young Thoroughbred horses can facilitate muscle fibre hypertrophy and increase the oxidative capacity of type IIX fibres, which could potentially enhance stamina at high speeds. To apply this result to practical training, further studies are needed to determine more effective and safe intensities of controlled exercise.

School-Based Smoking Prevention Programs for Middle School Students in Nowshahr- Iran: a Randomized Controlled Trial

Directory of Open Access Journals (Sweden)

Maryam Khazaee-Pool

2016-11-01

Full Text Available Background: Smoking among youths is a main public health concern, and detecting predictors of smoking is essential for designing preventive programs. Any interventional program should plan with highlighting on behavioral change models and based on operative interventional program. So, this study aimed to investigate school-based smoking prevention programs for middle school students in Nowshahr, Iran.Materials and Methods: A quasi-experimental study was performed with 280 male students aged 15-17 years selected by multistage sampling. For this purpose, 6 middle schools were randomly recruited from male students in Nowshahr- Iran. Then, 140 students were randomly chosen for each the experimental and the control groups. After pretest, educational program based on Health Belief Model were performed in experimental group. Also, post-test was applied four months after interventional program in both experimental and control group.Results: Based on the results, the prevalence of smoking was higher at age 14 old in both experimental (38.7% and control (30 % groups. About 35% of participants in the experimental group and 33.6% in control group had smoker father. Additionally, 10% in experimental group and 7.8% in control group had smoker mother. Most main cause for smoking in 57.9% of the experimental group and 52.63% of the control group was reducing anxiety. Results also shown that there was a significant difference between students in the experimental and control groups after performing educational program in the mean scores of perceived susceptibility, perceived severity, perceived benefits, perceived barriers, perceived self-efficacy, and preventive behaviors of smoking (P < 0.05.Conclusion: By performing educational program, it was found that the prevalence of cigarette smoking was decreased in the intervention group. So, with a better understanding of factors affecting on this complex behavior (cigarette smoking, it can be a valuable phase to

State registration and inspection programs for particle accelerators

International Nuclear Information System (INIS)

Bailey, E.D.

1976-01-01

The Suggested State Regulations for Control of Radiation(SSRCR) are recommended by the Council of State Governments and the National Conference of Radiation Control Program Directors as the model regulations which states should adopt in order to have adequate regulation and uniformity from state to state. These regulations are used as a basis for reviewing the current status of accelerator regulation in each state. The SSRCR does contain a separate part for registration (Part B--Registration of Radiation Machine Facilities and Services) and a separate part (Part I--Radiation Safety Requirements for Particle Accelerators) with specific requirements for the possession and use of accelerators. In addition, medical accelerators have additional requirements in Part F--X-Rays in The Heating Acts. These regulations specify requirements related to limitations of use, shielding and safety design requirements, control and interlock systems, warning devices, operating procedures, radiation monitoring, and calibration of medical accelerators

CEBAF Accelerator Achievements

International Nuclear Information System (INIS)

Chao, Y C; Drury, M; Hovater, C; Hutton, A; Krafft, G A; Poelker, M; Reece, C; Tiefenback, M

2011-01-01

In the past decade, nuclear physics users of Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) have benefited from accelerator physics advances and machine improvements. As of early 2011, CEBAF operates routinely at 6 GeV, with a 12 GeV upgrade underway. This article reports highlights of CEBAF's scientific and technological evolution in the areas of cryomodule refurbishment, RF control, polarized source development, beam transport for parity experiments, magnets and hysteresis handling, beam breakup, and helium refrigerator operational optimization.

Risk factors for falls with severe fracture in elderly people living in a middle-income country: a case control study

OpenAIRE

Coutinho, Evandro SF; Fletcher, Astrid; Bloch, Katia V; Rodrigues, Laura C

2008-01-01

Abstract Background Fracture after falling has been identified as an important problem in public health. Most studies of risk factors for fractures due to falls have been carried out in developed countries, although the size of the elderly population is increasing fast in middle income countries. The objective of this paper is to identify risk factors for fall related to severe fractures in those aged 60 or more in a middle-income country. Methods A case-control study was carried out in Rio d...

Three Patterns of Rising type 2 Diabetes Prevalence in the World: Need to Widen the Concept of Prevention in Individuals into Control in the Community

Directory of Open Access Journals (Sweden)

Madhur Dev Bhattarai

2009-04-01

for Asian and other similar populations. The population-based approaches with examples, considering developing countries, are outlined. The paper emphasizes the importance of keeping prepregnancy weight optimum, preferably below the middle of recommended BMI range, to avoid even sub-clinical maternal hyperglycemia, for prevention and control of accelerated rise in any population. Key Words: diabetes, diabetes control, diabetes epidemiology, diabetes prevention, prepregnancy weight

A LEGO paradigm for virtual accelerator concept

International Nuclear Information System (INIS)

Andrianov, S.; Ivanov, A.; Podzyvalov, E.

2012-01-01

The paper considers basic features of a Virtual Accelerator concept based on LEGO paradigm. This concept involves three types of components: different mathematical models for accelerator design problems, integrated beam simulation packages (i. e. COSY, MAD, OptiM and others), and a special class of virtual feedback instruments similar to real control systems (EPICS). All of these components should inter-operate for more complete analysis of control systems and increased fault tolerance. The Virtual Accelerator is an information and computing environment which provides a framework for analysis based on these components that can be combined in different ways. Corresponding distributed computing services establish interaction between mathematical models and low level control system. The general idea of the software implementation is based on the Service-Oriented Architecture (SOA) that allows using cloud computing technology and enables remote access to the information and computing resources. The Virtual Accelerator allows a designer to combine powerful instruments for modeling beam dynamics in a friendly way including both self-developed and well-known packages. In the scope of this concept the following is also proposed: the control system identification, analysis and result verification, visualization as well as virtual feedback for beam line operation. The architecture of the Virtual Accelerator system itself and results of beam dynamics studies are presented. (authors)

The Effects of Math Acceleration in Middle School at the High School Level

Science.gov (United States)

Dossenbach, Chris Payton

2017-01-01

The purpose of this mixed-methods capstone is to investigate the effectiveness of the math acceleration initiative that began in the studied school district in 2009 and the impact the initiative has had on mathematics enrollment at the high school level. This research project followed cohorts of students during the 2012-2013 and 2013-2014 school…

Changes in Hypertension Prevalence, Awareness, Treatment, and Control in High-, Middle-, and Low-Income Countries: An Update.

Science.gov (United States)

Cifkova, Renata; Fodor, George; Wohlfahrt, Peter

2016-08-01

The aim of this paper was to critically evaluate recent publications on hypertension treatment and control in regions by income. Prevalence of hypertension is increasing worldwide, most prominently in low-income countries. Awareness, treatment, and control are most successful in North America while remaining a challenge in middle- and low-income countries. Easy access to medical care and aggressive use of pharmacotherapy are the key strategies which have proved to be successful in reducing the burden of hypertension on the population level.

Continuity of Accelerator Operations during an Extended Pandemic

International Nuclear Information System (INIS)

Noel Okay

2010-01-01

The Operations group for the Continuous Electron Accelerator Facility in Newport News Virginia has developed a Continuity of Operations plan for pandemic conditions when high absenteeism may impact accelerator control room operations. Protocols to address both the potential spread of illnesses in the control room environment as well as maintaining minimum staffing requirements for contiguous accelerator operation will be presented. During acute pandemic conditions local government restrictions may prevent continued operations but during extended periods of high absenteeism accelerator operations can continue when some added precautionary measures and staffing adjustments are made in the way business is done.

Sterilization and birth control in the shadow of eugenics: married, middle-class women in Alberta, 1930-1960s.

Science.gov (United States)

Dyck, Erika

2014-01-01

The history of eugenic sterilization connotes draconian images of coerced and involuntary procedures robbing men and women of their reproductive health. While eugenics programs often fit this characterization, there is another, smaller, and less obvious legacy of eugenics that arguably contributed to a more empowering image of reproductive health. Sexual sterilization surgeries as a form of contraception began to gather momentum alongside eugenics programs in the middle of the 20th century and experiences among prairie women serve as an illustrative example. Alberta maintained its eugenics program from 1929 to 1972 and engaged in thousands of eugenic sterilizations, but by the 1940s middle-class married women pressured their Albertan physicians to provide them with sterilization surgeries to control fertility, as a matter of choice. The multiple meanings and motivations behind this surgery introduced a moral quandary for physicians, which encourages medical historians to revisit the history of eugenics and its relationship to the contemporaneous birth control movement.

High-resolution 3D-GRE imaging of the abdomen using controlled aliasing acceleration technique - a feasibility study

Energy Technology Data Exchange (ETDEWEB)

AlObaidy, Mamdoh; Ramalho, Miguel; Busireddy, Kiran K.R.; Liu, Baodong; Burke, Lauren M.; Altun, Ersan; Semelka, Richard C. [University of North Carolina at Chapel Hill, Department of Radiology, Chapel Hill, NC (United States); Dale, Brian M. [Siemens Medical Solutions, MR Research and Development, Morrisville, NC (United States)

2015-12-15

To assess the feasibility of high-resolution 3D-gradient-recalled echo (GRE) fat-suppressed T1-weighted images using controlled aliasing acceleration technique (CAIPIRINHA-VIBE), and compare image quality and lesion detection to standard-resolution 3D-GRE images using conventional acceleration technique (GRAPPA-VIBE). Eighty-four patients (41 males, 43 females; age range: 14-90 years, 58.8 ± 15.6 years) underwent abdominal MRI at 1.5 T with CAIPIRINHA-VIBE [spatial resolution, 0.76 ± 0.04 mm] and GRAPPA-VIBE [spatial resolution, 1.17 ± 0.14 mm]. Two readers independently reviewed image quality, presence of artefacts, lesion conspicuity, and lesion detection. Kappa statistic was used to assess interobserver agreement. Wilcoxon signed-rank test was used for image qualitative pairwise comparisons. Logistic regression with post-hoc testing was used to evaluate statistical significance of lesions evaluation. Interobserver agreement ranged between 0.45-0.93. Pre-contrast CAIPIRINHA-VIBE showed significantly (p < 0.001) sharper images and lesion conspicuity with decreased residual aliasing, but more noise enhancement and inferior image quality. Post-contrast CAIPIRINHA-VIBE showed significantly (p < 0.001) sharper images and higher lesion conspicuity, with less respiratory motion and residual aliasing artefacts. Inferior fat-suppression was noticeable on CAIPIRINHA-VIBE sequences (p < 0.001). High in-plane resolution abdominal 3D-GRE fat-suppressed T1-weighted imaging using controlled-aliasing acceleration technique is feasible and yields sharper images compared to standard-resolution images using standard acceleration, with higher post-contrast image quality and trend for improved hepatic lesions detection. (orig.)

High-resolution 3D-GRE imaging of the abdomen using controlled aliasing acceleration technique - a feasibility study

International Nuclear Information System (INIS)

AlObaidy, Mamdoh; Ramalho, Miguel; Busireddy, Kiran K.R.; Liu, Baodong; Burke, Lauren M.; Altun, Ersan; Semelka, Richard C.; Dale, Brian M.

2015-01-01

To assess the feasibility of high-resolution 3D-gradient-recalled echo (GRE) fat-suppressed T1-weighted images using controlled aliasing acceleration technique (CAIPIRINHA-VIBE), and compare image quality and lesion detection to standard-resolution 3D-GRE images using conventional acceleration technique (GRAPPA-VIBE). Eighty-four patients (41 males, 43 females; age range: 14-90 years, 58.8 ± 15.6 years) underwent abdominal MRI at 1.5 T with CAIPIRINHA-VIBE [spatial resolution, 0.76 ± 0.04 mm] and GRAPPA-VIBE [spatial resolution, 1.17 ± 0.14 mm]. Two readers independently reviewed image quality, presence of artefacts, lesion conspicuity, and lesion detection. Kappa statistic was used to assess interobserver agreement. Wilcoxon signed-rank test was used for image qualitative pairwise comparisons. Logistic regression with post-hoc testing was used to evaluate statistical significance of lesions evaluation. Interobserver agreement ranged between 0.45-0.93. Pre-contrast CAIPIRINHA-VIBE showed significantly (p < 0.001) sharper images and lesion conspicuity with decreased residual aliasing, but more noise enhancement and inferior image quality. Post-contrast CAIPIRINHA-VIBE showed significantly (p < 0.001) sharper images and higher lesion conspicuity, with less respiratory motion and residual aliasing artefacts. Inferior fat-suppression was noticeable on CAIPIRINHA-VIBE sequences (p < 0.001). High in-plane resolution abdominal 3D-GRE fat-suppressed T1-weighted imaging using controlled-aliasing acceleration technique is feasible and yields sharper images compared to standard-resolution images using standard acceleration, with higher post-contrast image quality and trend for improved hepatic lesions detection. (orig.)

Dietary habits and locus of control assessed in middle-school pupils from the Malopolska region of Poland.

Science.gov (United States)

Gacek, Maria

2013-01-01

The formative years of adolescence are a crucial time for developing eating habits which, amongst other factors, are determined by personality traits. The aim of the study was to estimate eating behaviour in a group of middle school pupils according to gender and locus of control (LOC). Subjects were n = 200 boys and n = 200 girls, aged 14-16 living in the Malopolska region of Poland who were surveyed by questionnaire about their eating habits. A standardised Delta questionnaire, by Drwal, was used to assess LOC. Based on the median from the raw LOC scale scores, groups of boys and girls were thereby identified as having high internal (below the median) or high external (above the median) loci of control. The Chi2 test assessed the dependence between LOC and eating habits using PQStat software ver. 1.4.2.324 adopting values of p differences in certain eating behaviour have been found in middle school students that relate to their gender and LOC. The more rational and appropriate choices were taken by subjects with an internal LOC.

Specifications, quality control, manufacturing, and testing of accelerator magnets

CERN Document Server

Einfeld, D

2010-01-01

The performance of the magnets plays an important role in the functioning of an accelerator. Most of the magnets are designed at the accelerator laboratory and built by industry. The link between the laboratory and the manufacturer is the contract containing the Technical Specifications of the magnets. For an overview of the contents of the Technical Specifications, the specifications for the magnets of ALBA (bending, quadrupole, and sextupole) are described in this paper. The basic rules of magnet design are reviewed in Appendix A.

CAS CERN Accelerator School: Power converters for particle accelerators

International Nuclear Information System (INIS)

Turner, S.

1990-01-01

This volume presents the proceedings of the fifth specialized course organized by the CERN Accelerator School, the subject on this occasion being power converters for particle accelerators. The course started with lectures on the classification and topologies of converters and on the guidelines for achieving high performance. It then went on to cover the more detailed aspects of feedback theory, simulation, measurements, components, remote control, fault diagnosis and equipment protection as well as systems and grid-related problems. The important topics of converter specification, procurement contract management and the likely future developments in semiconductor components were also covered. Although the course was principally directed towards DC and slow-pulsed supplies, lectures were added on fast converters and resonant excitation. Finally the programme was rounded off with three seminars on the related fields of Tokamak converters, battery energy storage for electric vehicles, and the control of shaft generators in ships. (orig.)

Cognitive Remediation in Middle-Aged or Older Inpatients with Chronic Schizophrenia: A Randomized Controlled Trial in Korea

Directory of Open Access Journals (Sweden)

Kee-Hong Choi

2018-02-01

Full Text Available Background: Accumulating evidence indicates that cognitive remediation (CR is effective for improving various cognitive deficits in adult patients with schizophrenia. Although reports of brain plasticity in older adults and the service needs for chronic patients with schizophrenia are increasing, very few randomized controlled trials of CR have been conducted in middle-aged or older inpatients with chronic schizophrenia. We investigated the efficacy of individualized CR on the cognitive impairments of middle-aged or older inpatients with chronic schizophrenia within the context of comprehensive psychiatric rehabilitation (PR by comparing the results obtained with PR only and treatment as usual (TAU.Method: Fifty-seven middle-aged and older individuals with chronic schizophrenia and mild to moderate cognitive deficits were enrolled. Thirty-eight who were undergoing PR were randomly assigned to CR + PR (N = 19 or PR-only (N = 19 groups. Nineteen participants who were undergoing TAU without CR or PR were evaluated pre- and post-treatment.Results: CR was easily provided and well received (drop-out rates = 5.3% by middle-aged or older psychiatric inpatients. Compared to the PR-Only or TAU patients, patients in the CR + PR group showed greater improvement in executive functioning. Compared to TAU patients, CR + PR and PR-only patients showed greater improvement in logical memory. More patients in the CR + PR group improved clinically significantly in executive functioning and logical memory, compared with the PR-only and TAU patients.Conclusions: These results suggested that CR improved some cognitive deficits in middle-aged or older inpatients with chronic schizophrenia and that it was effective as an adjunctive treatment to the usual PR services provided in inpatient settings.Clinical Registration: KCT0002609

Virtual gap dielectric wall accelerator

Science.gov (United States)

Caporaso, George James; Chen, Yu-Jiuan; Nelson, Scott; Sullivan, Jim; Hawkins, Steven A

2013-11-05

A virtual, moving accelerating gap is formed along an insulating tube in a dielectric wall accelerator (DWA) by locally controlling the conductivity of the tube. Localized voltage concentration is thus achieved by sequential activation of a variable resistive tube or stalk down the axis of an inductive voltage adder, producing a "virtual" traveling wave along the tube. The tube conductivity can be controlled at a desired location, which can be moved at a desired rate, by light illumination, or by photoconductive switches, or by other means. As a result, an impressed voltage along the tube appears predominantly over a local region, the virtual gap. By making the length of the tube large in comparison to the virtual gap length, the effective gain of the accelerator can be made very large.

Sub-clinical middle ear malfunctions in elderly patients; prevalence ...

African Journals Online (AJOL)

... absent acoustic reflex. Keywords: Middle ear malfunctions, elderly patients. ... hearing loss, had audiometric changes suggestive of such. We regarded such .... predictors of silent middle ear malfunction (control for Age and Sex). Variable.

Acceleration, current amplification and emittance in MBE-4, an experimental beam induction linear accelerator for heavy ions

International Nuclear Information System (INIS)

Warwick, A.I.; Gough, D.E.; Keefe, D.; Meuth, H.

1988-10-01

We report on the implementation of a second schedule of acceleration and current amplification in MBE-4. Control of the beam current within the bunch is improved over that in the first schedule by the addition of several small amplitude induction pulsers to compensate for acceleration errors and to control the ends of the bunch. Measurements of the longitudinal and transverse emittance are presented. 5 refs., 3 figs., 1 tab

Implementing complex innovations: factors influencing middle manager support.

Science.gov (United States)

Chuang, Emmeline; Jason, Kendra; Morgan, Jennifer Craft

2011-01-01

Middle manager resistance is often described as a major challenge for upper-level administrators seeking to implement complex innovations such as evidence-based protocols or new skills training. However, factors influencing middle manager support for innovation implementation are currently understudied in the U.S. health care literature. This article examined the factors that influence middle managers' support for and participation in the implementation of work-based learning, a complex innovation adopted by health care organizations to improve the jobs, educational pathways, skills, and/or credentials of their frontline workers. We conducted semistructured interviews and focus groups with 92 middle managers in 17 health care organizations. Questions focused on understanding middle managers' support for work-based learning as a complex innovation, facilitators and barriers to the implementation process, and the systems changes needed to support the implementation of this innovation. Factors that emerged as influential to middle manager support were similar to those found in broader models of innovation implementation within the health care literature. However, our findings extend previous research by developing an understanding about how middle managers perceived these constructs and by identifying specific strategies for how to influence middle manager support for the innovation implementation process. These findings were generally consistent across different types of health care organizations. Study findings suggest that middle manager support was highest when managers felt the innovation fit their workplace needs and priorities and when they had more discretion and control over how it was implemented. Leaders seeking to implement innovations should consider the interplay between middle managers' control and discretion, their narrow focus on the performance of their own departments or units, and the dedication of staff and other resources for empowering their

Linear resonance acceleration of pellets

International Nuclear Information System (INIS)

Mills, R.G.

1978-01-01

A possible requirement for the acceleration of macroscopic pellets to velocities exceeding 10 4 meters per second implies the development of new apparatus. A satisfactory approach might be the linear resonance accelerator. Such apparatus would require the charging of pellets to very high values not yet demonstrated. The incompatibility of phase stability with radial stability in these machines may require abandoning phase stability and adopting feedback control of the accelerating voltage to accommodate statistical fluctuations in the charge to mass ratio of successive pellets

Use of the TACL [Thaumaturgic Automated Control Logic] system at CEBAF [Continuous Electron Beam Accelerator Facility] for control of the Cryogenic Test Facility

International Nuclear Information System (INIS)

Navarro, E.; Keesee, M.; Bork, R.; Grubb, C.; Lahti, G.; Sage, J.

1989-01-01

A logic-based control software system, called Thaumaturgic Automated Control Logic (TACL), is under development at the Continuous Electron Beam Accelerator Facility in Newport News, VA. The first version of the software was placed in service in November, 1987 for control of cryogenics during the first superconducting RF cavity tests at CEBAF. In August, 1988 the control system was installed at the Cryogenic Test Facility (CTF) at CEBAF. CTF generated liquid helium in September, 1988 and is now in full operation for the current round of cavity tests. TACL is providing a powerful and flexible controls environment for the operation of CTF. 3 refs

The Control System of CERN Accelerators Vacuum (LS1 Activities and New Developments)

CERN Document Server

Gomes, P; Bellorini, F; Blanchard, S; Boivin, J P; Gama, J; Girardot, G; Pigny, G; Rio, B; Vestergard, H; Kopylov, L; Merker, S; Mikheev, M

2014-01-01

After 3 years of operation, the LHC entered its first Long Shutdown period (LS1), in February 2013 [1]. Major consolidation and maintenance works are being performed across the whole CERN’s Accelerator chain, in order to prepare the LHC to restart at higher energy, in 2015. The injector chain shall resume earlier, in mid-14. We report about the on-going vacuum-controls projects. Some of them concern the renovation of the controls of certain machines; others are associated with the consolidations of the vacuum systems of LHC and its injectors; and a few are completely new installations. ue to the wide age-span of the existing vacuum installations, there is a mix of design philosophies and of control-equipment generations. The renovations and the novel projects offer an opportunity to improve the uniformity and efficiency of vacuum controls by: reducing the number of equipment versions with similar functionality; identifying, naming, labelling, and documenting all pieces of equipment; homogenizing the contr...

JKJ accelerator timing system

International Nuclear Information System (INIS)

Ohmori, C.; Mori, Y.; Yoshii, M.; Yamamoto, M.

2001-01-01

The JKJ (JAERl-KEK Joint Project) accelerator complex consists of the linear accelerator, 3 GeV and 50 GeV synchrotrons. To minimize the beam loss during the beam transfer from the 3 GeV synchrotron to the 50 GeV one, the synchronization of the two RF system of the rings is very important. To reduce the background from the high and low momentum neutron, the neutron beam chopper will be employed. The 3 GeV RF will be also synchronized to the chopper timing when the beam goes to the neutron facility. The whole timing control system of these accelerators and chopper will be described. (author)

Vibration acceleration promotes bone formation in rodent models.

Directory of Open Access Journals (Sweden)

Ryohei Uchida

Full Text Available All living tissues and cells on Earth are subject to gravitational acceleration, but no reports have verified whether acceleration mode influences bone formation and healing. Therefore, this study was to compare the effects of two acceleration modes, vibration and constant (centrifugal accelerations, on bone formation and healing in the trunk using BMP 2-induced ectopic bone formation (EBF mouse model and a rib fracture healing (RFH rat model. Additionally, we tried to verify the difference in mechanism of effect on bone formation by accelerations between these two models. Three groups (low- and high-magnitude vibration and control-VA groups were evaluated in the vibration acceleration study, and two groups (centrifuge acceleration and control-CA groups were used in the constant acceleration study. In each model, the intervention was applied for ten minutes per day from three days after surgery for eleven days (EBF model or nine days (RFH model. All animals were sacrificed the day after the intervention ended. In the EBF model, ectopic bone was evaluated by macroscopic and histological observations, wet weight, radiography and microfocus computed tomography (micro-CT. In the RFH model, whole fracture-repaired ribs were excised with removal of soft tissue, and evaluated radiologically and histologically. Ectopic bones in the low-magnitude group (EBF model had significantly greater wet weight and were significantly larger (macroscopically and radiographically than those in the other two groups, whereas the size and wet weight of ectopic bones in the centrifuge acceleration group showed no significant difference compared those in control-CA group. All ectopic bones showed calcified trabeculae and maturated bone marrow. Micro-CT showed that bone volume (BV in the low-magnitude group of EBF model was significantly higher than those in the other two groups (3.1±1.2mm3 v.s. 1.8±1.2mm3 in high-magnitude group and 1.3±0.9mm3 in control-VA group, but

Quality control methods for linear accelerator radiation and mechanical axes alignment.

Science.gov (United States)

Létourneau, Daniel; Keller, Harald; Becker, Nathan; Amin, Md Nurul; Norrlinger, Bernhard; Jaffray, David A

2018-06-01

The delivery accuracy of highly conformal dose distributions generated using intensity modulation and collimator, gantry, and couch degrees of freedom is directly affected by the quality of the alignment between the radiation beam and the mechanical axes of a linear accelerator. For this purpose, quality control (QC) guidelines recommend a tolerance of ±1 mm for the coincidence of the radiation and mechanical isocenters. Traditional QC methods for assessment of radiation and mechanical axes alignment (based on pointer alignment) are time consuming and complex tasks that provide limited accuracy. In this work, an automated test suite based on an analytical model of the linear accelerator motions was developed to streamline the QC of radiation and mechanical axes alignment. The proposed method used the automated analysis of megavoltage images of two simple task-specific phantoms acquired at different linear accelerator settings to determine the coincidence of the radiation and mechanical isocenters. The sensitivity and accuracy of the test suite were validated by introducing actual misalignments on a linear accelerator between the radiation axis and the mechanical axes using both beam steering and mechanical adjustments of the gantry and couch. The validation demonstrated that the new QC method can detect sub-millimeter misalignment between the radiation axis and the three mechanical axes of rotation. A displacement of the radiation source of 0.2 mm using beam steering parameters was easily detectable with the proposed collimator rotation axis test. Mechanical misalignments of the gantry and couch rotation axes of the same magnitude (0.2 mm) were also detectable using the new gantry and couch rotation axis tests. For the couch rotation axis, the phantom and test design allow detection of both translational and tilt misalignments with the radiation beam axis. For the collimator rotation axis, the test can isolate the misalignment between the beam radiation axis

Accelerator Technology Division annual report, FY 1991

International Nuclear Information System (INIS)

1992-04-01

This report discusses the following programs: The Ground Test Accelerator Program; APLE Free-Electron Laser Program; Accelerator Transmutation of Waste; JAERI, OMEGA Project, and Intense Neutron Source for Materials Testing; Advanced Free-Electron Laser Initiative; Superconducting Super Collider; The High-Power Microwave Program; Φ Factory Collaboration; Neutral Particle Beam Power System Highlights; Accelerator Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Accelerator Design and Engineering; Radio-Frequency Technology; Free-Electron Laser Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operations

Charged particle accelerators for practice

International Nuclear Information System (INIS)

Arzumanov, A.A.

1988-01-01

Characteristics of some accelerators operating in the world are given, capabilities of accelerator technique are demonstrated. Examples of wide application of accelerators in radiation-chemical technology as well as for defectoscopy of massive metal products and impurity ion implantation when producing semiconductor elements are presented. Works on nuclear filter production are characterized by high efficiency. Wide application of synchrotron radiation is described. Various accelerators can be applied during element analysis in geology, metallurgy, ecology. Application of accelerators ''in particular, cyclotrons for radioisotope production as well as in radiotherapy in medicine appears to be important. An isochronous cyclotron with controlled ion energy, at which applied works concerning a number of considered trends in the field of radiation physics and radiation physical metallurgy, element analysis, radiation resistance of electronic circuits and components are conducted, is in operation at the IYaPh of the Kazakh Academy of Sciences. Production of tallium-201 for cardiologic invstigations deserves a special attention. An electrostatic heavy ion accelerator which allows one to produce the beams of accelerated ions of elements from hydrogen to uranium is under commissioning

Low-velocity superconducting accelerating structures

International Nuclear Information System (INIS)

Delayen, J.R.

1990-01-01

The present paper reviews the status of RF superconductivity as applied to low-velocity accelerating properties. Heavy-ion accelerators must accelerate efficiently particles which travel at a velocity much smaller than that of light particles, whose velocity changes along accelerator, and also different particles which have different velocity profiles. Heavy-ion superconducting accelerators operate at frequencies which are lower than high-energy superconducting accelerators. The present paper first discusses the basic features of heavy-ion superconducting structures and linacs. Design choices are then addressed focusing on structure geometry, materials, frequency, phase control, and focusing. The report also gives an outline of the status of superconducting booster projects currently under way at the Argonne National Laboratory, SUNY Stony Brook, Weizmann Institute, University of Washington, Florida State, Saclay, Kansas State, Daresbury, Japanese Atomic Energy Research Institute, Legnaro, Bombay, Sao Paulo, ANU (Canberra), and Munich. Recent developments and future prospects are also described. (N.K.) 68 refs

Accelerant-related burns and drug abuse: Challenging combination.

Science.gov (United States)

Leung, Leslie T F; Papp, Anthony

2018-05-01

Accelerants are flammable substances that may cause explosion when added to existing fires. The relationships between drug abuse and accelerant-related burns are not well elucidated in the literature. Of these burns, a portion is related to drug manufacturing, which have been shown to be associated with increased burn complications. 1) To evaluate the demographics and clinical outcomes of accelerant-related burns in a Provincial Burn Centre. 2) To compare the clinical outcomes with a control group of non-accelerant related burns. 3) To analyze a subgroup of patients with history of drug abuse and drug manufacturing. Retrospective case control study. Patient data associated with accelerant-related burns from 2009 to 2014 were obtained from the British Columbia Burn Registry. These patients were compared with a control group of non-accelerant related burns. Clinical outcomes that were evaluated include inhalational injury, ICU length of stay, ventilator support, surgeries needed, and burn complications. Chi-square test was used to evaluate categorical data and Student's t-test was used to evaluate mean quantitative data with the p value set at 0.05. A logistic regression model was used to evaluate factors affecting burn complications. Accelerant-related burns represented 28.2% of all burn admissions (N=532) from 2009 to 2014. The accelerant group had higher percentage of patients with history of drug abuse and was associated with higher TBSA burns, ventilator support, ICU stay and pneumonia rates compared to the non-accelerant group. Within the accelerant group, there was no difference in clinical outcomes amongst people with or without history of drug abuse. Four cases were associated with methamphetamine manufacturing, all of which underwent ICU stay and ventilator support. Accelerant-related burns cause significant burden to the burn center. A significant proportion of these patients have history of drug abuse. Copyright © 2017 Elsevier Ltd and ISBI. All rights

Future directions in controlling the LAMPF-PSR accelerator complex at Los Alamos National Laboratory